Obesity in children: bariatric surgery Search date August 2014 Dexter Canoy and TienYu Owen Yang ABSTRACT INTRODUCTION: The prevalence of childhood obesity in the UK and in many countries worldwide remains high. Behavioural interventions to modify lifestyle, such as diet and physical activity, usually form part of weight management strategies for obese children. Whether or not surgical interventions are effective and safe in treating childhood obesity is unclear. METHODS AND OUTCOMES: We conducted a systematic overview, aiming to answer the following clinical question: What are the effects of surgical interventions for the treatment of childhood obesity? We searched Medline, Embase, The Cochrane Library, and other important databases up to August 2014 (BMJ Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this overview). RESULTS: At this update, after deduplication and removal of conference abstracts, 67 records were screened for inclusion in the overview. Appraisal of titles and abstracts led to the exclusion of 19 studies and the further review of 48 full publications. Of the 48 full articles evaluated, two systematic reviews were included at this update. CONCLUSIONS: In this systematic overview, we categorised the efficacy for two comparisons based on information about the effectiveness and safety of bariatric surgery versus no intervention and different types of bariatric surgery versus each other.
QUESTIONS What are the effects of surgical interventions for the treatment of childhood obesity?. . . . . . . . . . . . . . . . . . . . . 4 INTERVENTIONS OBESITY IN CHILDREN: SURGICAL INTERVENTIONS Unknown effectiveness
Different types of bariatric surgery versus each other . . 5
Bariatric surgery versus no treatment, usual care, or waiting list control . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Key points • Obesity is the result of long-term energy imbalances, where daily energy intake exceeds daily energy expenditure. Obesity in children is associated with physical as well as psychosocial problems. Long-term adverse health consequences of childhood obesity may include increased risk for chronic disease conditions, including cancer and cardiovascular and metabolic diseases in adulthood. Most obese children stay obese as adults. • Obesity is increasing among children and adolescents, with 16% of boys and 15% of girls in the UK aged 2 to 15 years being obese in 2013. The prevalence of severe obesity is unclear and depends on the classification used to define this condition. However, it has been estimated to be 1% to 4% of children aged 4 to 5 years and 10 to 11 years in the UK in 2011–2012, and up to 8% of children aged 2 to 9 years in the US. • We don't know how effective and safe bariatric surgery is versus no intervention, or different types of bariatric surgery are versus each other, in treating obesity in children, particularly in children with severe obesity, as we found no relevant RCTs. Surgical expertise, specialist care, the target population (i.e., children), and some uncertainties on adverse consequences of bariatric surgery in the long-term are some of the barriers that may have limited the number of RCTs conducted to evaluate the effectiveness and safety of surgical interventions to treat morbid obesity in children. • Future RCTs may require multi-centre collaboration to assess both short-term and long-term follow-up. Findings from existing, well-characterised prospective cohorts of children who underwent bariatric surgery should be relevant, particularly in informing how RCTs should be designed in the future. Future RCTs should also address questions on effectiveness and safety of the different surgical interventions for obesity in children, including the increasingly used technique of laparoscopic sleeve gastrectomy. Clinical context
GENERAL BACKGROUND The prevalence of overweight children and childhood obesity remains high in the UK and in many countries worldwide. Lifestyle interventions form part of the main strategy to treat childhood obesity; however, the impact of these interventions is limited, particularly in morbidly obese children.There is a growing interest in the use of surgical interventions in the treatment and management of obesity in paediatric patients, but evidence for the benefits and harms of surgical interventions is unclear, and the cost-effectiveness of this intervention is unknown.
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The main purpose of this overview is to seek evidence from RCTs to assess physical, psychosocial, and quality-oflife outcomes of bariatric surgery in childhood obesity as compared to appropriate control (no intervention, usual care, or waiting list control), or of different types of bariatric surgery compared with each other.
COMMENTS ON EVIDENCE Two systematic reviews met our criteria. However, these reviews included mostly non-RCTs and studies without appropriate comparison groups. Some of the barriers that may have limited the number of RCTs conducted to evaluate the effectiveness and safety of surgical interventions to treat morbid obesity in children include: surgical expertise, specialist care, the target population (i.e., children), and some uncertainties on adverse consequences of bariatric surgery in the long term.
SEARCH AND APPRAISAL SUMMARY The update literature search for this review was carried out from the date of the last search, January 2010, to August 2014. For more information on the electronic databases searched and criteria applied during assessment of studies for potential relevance to the overview, please see the Methods section. After deduplication and removal of conference abstracts, 67 records were screened for inclusion in the overview. Appraisal of titles and abstracts led to the exclusion of 19 studies and the further review of 48 full publications. Of the 48 full articles evaluated, two systematic reviews were included at this update.
ADDITIONAL INFORMATION Lifestyle interventions, usually delivered through behavioural programmes, may be effective in reducing excess [1] [2] [3] [4] [5] weight in obese children, but these interventions may have limited impact in children with severe [1] [6] obesity. Even if weight loss is achieved through lifestyle modification, the magnitude of the effect is small and severely obese children remain obese (please see the previous version of this overview where we have considered the evidence for lifestyle interventions). The indication and patient selection criteria for bariatric surgery remain poorly defined, but the target patient group in paediatric populations is likely to be limited to older children with severe obesity (e.g., adolescents). Bariatric surgery may be offered as a treatment option for morbidly obese children, but [1] [7] is usually reserved for exceptional circumstances in settings where this treatment is available and accessible. There is growing interest in the use of bariatric surgery as a treatment option for obesity among paediatric patients, [1] [6] [8] [9] but the evidence for the effectiveness and safety of such surgical intervention is unclear. DEFINITION
Obesity is a chronic condition characterised by an excess of body fat that presents a risk to health. Body mass index (BMI), calculated as weight (in kilograms) divided by squared height (in metres), is a crude yet simple and widely used measure in the identification of overweight and obesity as it [10] is highly correlated with body fat. In young children and adolescents, BMI varies with age and sex. It typically rises during the first months after birth, falls after the first year, and rises again [11] around the sixth year of life and into adolescence. Thus, a child's BMI is usually compared to age- and sex-specific BMI of a reference population to obtain the BMI percentile of the child relative to that population. A BMI above the 95th percentile is variably defined as obese, which generally indicates a need for intervention. A small subgroup of obese children are considered to have severe obesity (also described as extreme or morbid obesity), but there is no standard definition to identify this group, and their classification is largely based on the very extreme end of the BMI percentile 2 distribution, or the BMI percentile distribution equivalent to the adult BMI of 35 kg/m or higher [1] [12] [13] [14] [15] (class II and III obesity).
INCIDENCE/ PREVALENCE
The prevalence of obesity (generally, BMI >95th percentile) has been increasing among children and adolescents. In the UK in 2013, it was estimated that 16% of boys and 15% of girls aged 2 to 15 years were obese, an increase from 11% of boys and 12% of girls in 1995, but a decrease from [16] 18% to 19% of both boys and girls from when the prevalence peaked in 2004 and 2005. This pattern suggested an increasing prevalence of obesity until the mid-2000s, when the prevalence seemed to have plateaued. Among children followed for more than 9 years from age 5, 12% became obese when they reached age 14 years, with an incidence rate of 26.5 per 1000 person-years [17] among non-obese at baseline. The proportion of extremely obese children varies with the classification used. In the National Child Measurement Programme in England in 2011 to 2012, around 2% of children 4 to 5 years old and 3% to 4% of those 10 to 11 years old had severe obesity, based on classifying severe obesity as equal to or above the 99.6th percentile on the UK 1990 growth chart; or 1% to 2% of children 4 to 5 years old and 1% of those 10 to 11 years old when [13] using the International Obesity Task Force classification. The prevalence of severe obesity among 4- to 5-year-olds hardly changed between 2006–2007 and 2011–2012, but there was a marked increase over the same period among 10- to 11-year-olds. In the US, little has changed in the prevalence of overweight children, but the proportions of obese, as well as severely obese, [15] children continued to rise between 1999–2000 and 2011–2012. In 2011–2012, up to 8% of [1] [15] children in the US aged 2 to 19 years may be considered to be severely obese.
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[18]
AETIOLOGY/ Obesity is the result of disproportionate energy consumption outweighing energy expenditure. [19] [20] RISK FACTORS The genetic basis of obesity has been well investigated, and genetic factors are likely to [21] play an important role in the aetiology of severe obesity. However, the increase in obesity prevalence in the past few decades is less likely to be explained by changes in the human gene pool, and more likely to be related to environmental changes that promote excessive food intake [22] [23] [24] and discourage physical activity (increasing sedentariness); and changes to other distal factors that may influence diet and physical activity, including parental education, social de[11] [25] privation, infant feeding patterns, and intrauterine exposures. Physical activity levels have decreased over the years. Only 36% of children and adolescents in the US meet the recommended [26] levels of physical activity. Among British children aged 5 to 15 years in 2012, only 21% of boys and 16% of girls met the minimum physical activity level required to achieve health benefits, down [27] from 28% of boys and 19% of girls in 2008. Less commonly, obesity may also be induced by drugs (e.g., high-dose glucocorticoids), neuroendocrine disorders (e.g., Cushing's syndrome), or [11] inherited disorders (e.g., Down's syndrome and Prader-Willi syndrome). PROGNOSIS
Most obese children will become obese adolescents. Obese children at age 5 years are four times [17] more likely to become obese at age 14 years than non-obese children. In longitudinal studies, most obese children and adolescents are also most likely to become obese adults as compared [28] [29] to non-obese children. Consequently, the obese children who remain obese in adulthood develop adverse morbidity and mortality outcomes later in life, including hypertension, dyslipidaemia, [11] [30] [31] diabetes, cardiovascular disease, sleep apnoea, osteoarthritis, and some cancers. [32] [33] [34] [35] The long-term adverse health risks associated with childhood obesity are potentially modifiable. The effect of childhood obesity on adult health outcomes is generally linked to the [35] development of a high adult BMI among obese children later in life. The associated risks are [36] reduced if these children achieve normal weight when they reach adulthood. Perhaps a less recognised but important short-term comorbidity of overweight/obesity, particularly in adolescent children, is functional impairment in several psychosocial domains, including social marginalisation, [11] [37] [38] [39] [40] low self-esteem, and impaired quality of life.
AIMS OF To achieve reduction in BMI and BMI percentile, and to prevent the morbidity and mortality associINTERVENTION ated with obesity, without undue adverse effects. OUTCOMES
Change in overweight proxy measures assessed in studies included mean weight loss (kg), 2 change in BMI (kg/m ), change in BMI z score, change in BMI percentile, change in percentage overweight, obesity or severe obesity, and change in other adiposity indicators (waist circumference, hip circumference, waist-hip ratio, total fat mass, percentage fat mass); mortality (associated with obesity); quality of life; secondary disease outcome any change in diabetes (diagnosis of diabetes, change in treatment for diabetes, change in fasting insulin or glucose levels), hypertension (diagnosis of hypertension, change in treatment for hypertension, change in blood pressure), dyslipidaemia (diagnosis of dyslipidaemia, change in treatment of dyslipidaemia, change in total or LDL-cholesterol); adverse effects.
METHODS
Search strategy BMJ Clinical Evidence search and appraisal August 2014. Databases used to identify studies for this systematic review include: Medline 1966 to August 2014, Embase 1980 to August 2014, The Cochrane Database of Systematic Reviews 2014, issue 3 (1966 to date of issue), the Database of Abstracts of Reviews of Effects (DARE), and the Health Technology Assessment (HTA) database. Inclusion criteria Study design criteria for inclusion in this systematic overview were systematic reviews and RCTs published in English and containing 10 or more individuals (at least 5 people per study arm), of whom more than 60% were followed up. RCTs could be open or blinded. Minimum length of follow-up was 12 weeks. We included studies in overweight and obese children (aged 18 years and younger), including children with a BMI above the 85th percentile for age and sex. We included RCTs and systematic reviews of RCTs where harms of an included intervention were assessed, applying the same study design criteria for inclusion as we did for benefits. BMJ Clinical Evidence does not necessarily report every study found (e.g., every systematic review). Rather, we report the most recent, relevant and comprehensive studies identified through an agreed process involving our evidence team, editorial team, and expert contributors. Evidence evaluation A systematic literature search was conducted by our evidence team, who then assessed titles and abstracts, and finally selected articles for full text appraisal against inclusion and exclusion criteria agreed a priori with our expert contributors. In consultation with the expert contributors, studies were selected for inclusion and all data relevant to this overview extracted into the benefits and harms section of the overview. In addition, information that did not meet our predefined criteria for inclusion in the benefits and harms section, may have been reported in the 'Further information on studies' or 'Comment' section. Adverse effects All serious adverse effects, or those adverse effects reported as statistically significant, were included in the harms section of the overview. Prespecified adverse effects identified as being clinically important were also reported, even if the results
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were not statistically significant. Although BMJ Clinical Evidence presents data on selected adverse effects reported in included studies, it is not meant to be, and cannot be, a comprehensive list of all adverse effects, contraindications, or interactions of included drugs or interventions. A reliable national or local drug database must be consulted for this information. Comment and Clinical guide sections In the Comment section of each intervention, our expert contributors may have provided additional comment and analysis of the evidence, which may include additional studies (over and above those identified via our systematic search) by way of background data or supporting information. As BMJ Clinical Evidence does not systematically search for studies reported in the Comment section, we cannot guarantee the completeness of the studies listed there or the robustness of methods. Our expert contributors add clinical context and interpretation to the Clinical guide sections where appropriate. Structural changes this update At this update, we have removed the following previously reported question: What are the effects of lifestyle interventions for the treatment of childhood obesity? Data and quality To aid readability of the numerical data in our reviews, we round many percentages to the nearest whole number. Readers should be aware of this when relating percentages to summary statistics such as relative risks (RRs) and odds ratios (ORs). BMJ Clinical Evidence does not report all methodological details of included studies. Rather, it reports by exception any methodological issue or more general issue that may affect the weight a reader may put on an individual study, or the generalisability of the result. These issues may be reflected in the overall GRADE analysis. QUESTION
What are the effects of surgical interventions for the treatment of childhood obesity?
OPTION
BARIATRIC SURGERY VERSUS NO TREATMENT, USUAL CARE, OR WAITING LIST CONTROL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
•
We found no direct information from RCTs on the effects of bariatric surgery versus no treatment, usual care, or waiting list controls for obesity in children.
•
Although bariatric surgery could potentially result in substantial weight loss among severely obese adolescents, evidence from well designed studies, particularly from RCTs, is limited. Uncertainties remain regarding clinical indications, identification of the relevant age group, cost, ethics, post-operative complications, and the short- and long-term benefits and harms of surgical procedures in this population. Benefits and harms
Bariatric surgery versus no treatment, usual care, or waiting list control: We found two systematic reviews (search dates 2010; and 2013) evaluating the effects of bariatric surgery for obe[41] [42] sity in children. The reviews included mostly non-RCTs, and did not identify any RCT comparing bariatric surgery with no treatment, usual care, or waiting list control. We found no additional or subsequent RCTs. Comment:
Findings from the review of mostly non-RCTs suggest that surgical intervention in the treatment of severe obesity could lead to a substantial amount of weight loss. However, the actual magnitude of weight loss is unclear. In one RCT, laparoscopic adjustable gastric banding resulted in substantial [43] weight loss when compared to an intensive lifestyle intervention, suggesting that, if the comparison group was given usual or conventional care for obese children, the magnitude of the effect could have been potentially greater in this study. However, the evidence for the effectiveness and safety of surgical interventions for the treatment of paediatric obesity remains poor. Uncertainties remain, particularly in relation to indications, patient selection criteria, post-operative complications, and beneficial and harmful outcomes beyond weight loss in the short and long term. How long is 'long term' to assess benefits and harms associated with surgical interventions for obesity in paediatric populations needs further elucidation considering that, depending on the age at surgical intervention, a 24-month follow-up would still mean assessing outcomes during childhood for some patients. There are registered RCTs (e.g., ClinicalTrials.gov identifiers NCT01700738 and NCT02378259), but the status of these trials is unclear as they are probably not actively recruiting patients into the study. Surgical expertise, specialist care, the target population (i.e., children), and some uncertainties on adverse consequences of bariatric surgery in the long-term are some of the barriers that may have limited the number of RCTs conducted to evaluate the effectiveness and safety of surgical interventions to treat morbid obesity in children. Future RCTs may require multi-centre collaboration to
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assess both short-term and long-term follow-up. Findings from existing, well-characterised prospective cohorts of children who underwent bariatric surgery should be relevant, particularly in [44] informing how RCTs should be designed in the future. Future RCTs should also address questions regarding the effectiveness and safety of the different surgical interventions for obesity in children, including the increasingly used technique of laparoscopic sleeve gastrectomy. Clinical guide Surgical treatment strategies for paediatric obesity are complex and may only be used in exceptional circumstances. Unlike in adults, there are several considerations that are specific to paediatric populations, including potential effects on growth and development, having a longer lifespan than adults to experience benefits and harms, and issues of consent. However, factors such as the local healthcare system and availability of specialist services are key considerations for surgical interventions for childhood obesity. As in adults, the magnitude of weight loss after bariatric surgery is likely to be substantial and could lead to improvements in cardiovascular and metabolic risk profile, at least in the short term. However, this treatment strategy for obesity is likely to be limited to severe obesity in paediatric patients who have reached appropriate chronological age and/or developmental stage, and only after other conventional weight management approaches have been explored. In addition, the absolute long-term benefits and harms of surgical treatment in this population are currently poorly described and quantified. OPTION
DIFFERENT TYPES OF BARIATRIC SURGERY VERSUS EACH OTHER. . . . . . . . . . . . . . . . . .
•
We found no direct information from RCTs on the effects of different types of bariatric surgery for obesity in children.
•
There are different bariatric surgery techniques that have been used to treat severe obesity in adolescence. One of the key considerations to the technique of choice is the reversibility or permanence of the procedure on the intestinal tract. We found no RCTs comparing the effectiveness between surgical techniques or evaluating the benefits and harms of the different bariatric surgery techniques. Benefits and harms
Different types of bariatric surgery versus each other: We found no systematic review or RCTs comparing different types of bariatric surgery with each other in children that met our inclusion criteria. Comment:
Clinical guide As in adults, laparoscopic adjustable gastric banding and the Roux-en-Y gastric bypass are two of the most commonly used procedures for surgical intervention in children with severe obesity, although laparoscopic sleeve gastrectomy has been increasingly used in some medical centres. However, there are no RCTs comparing the effectiveness of different surgical techniques in treating severe obesity. Observations from mostly non-RCTs suggest substantial reduction in BMI using the three surgical techniques, with the biggest reductions in BMI seen after Roux-en-Y gastric bypass [45] procedures. However, the evidence has been based on studies without appropriate comparison groups and with heterogeneity in the patient selection criteria, definition of severe obesity, and sample size. One of the key considerations for the procedure of choice is the reversibility or permanence of the procedure on the intestinal tract. However, the use of adjustable gastric banding in people under 18 years of age is currently not approved by the FDA and is usually performed 'offlabel'.
GLOSSARY Z score The z score reveals how many units of the standard deviation a case is above or below the mean.
SUBSTANTIVE CHANGES Bariatric surgery versus no treatment, usual care, or waiting list control Option restructured. Two systematic [41] [42] reviews added. Categorised as 'unknown effectiveness'. Different types of bariatric surgery versus each other Option restructured. No new evidence. Categorised as 'unknown effectiveness'.
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REFERENCES 1.
Kelly AS, Barlow SE, Rao G, et al; American Heart Association Atherosclerosis, Hypertension, and Obesity in the Young Committee of the Council on Cardiovascular Disease in the Young, Council on Nutrition, Physical Activity and Metabolism, and Council on Clinical Cardiology. Severe obesity in children and adolescents: identification, associated health risks, and treatment approaches: a scientific statement from the American Heart Association. Circulation 2013;128:1689–1712.[PubMed]
23.
French SA, Story M, Jeffery RW. Environmental influences on eating and physical activity. Annu Rev Public Health 2001;22:309–335.[PubMed]
24.
Lobstein T, Jackson-Leach R, Moodie ML, et al. Child and adolescent obesity: part of a bigger picture. Lancet 2015 Feb 18 [Epub ahead of print].[PubMed]
25.
Katzmarzyk PT, Barlow S, Bouchard C, et al. An evolving scientific basis for the prevention and treatment of pediatric obesity. Int J Obes (Lond) 2014;38:887–905.[PubMed]
26.
Eaton DK, Kann L, Kinchen S, et al. Youth risk behavior surveillance – United States, 2005. MMWR Surveill Summ 2006;55:1–108.[PubMed]
27.
Health and Social Care Information Centre. Health survey for England - 2013, trend tables. December 2014. Available at http://www.hscic.gov.uk/catalogue/PUB16077 (last accessed 9 May 2015).
28.
Gordon-Larsen P, Adair LS, Nelson MC, et al. Five-year obesity incidence in the transition period between adolescence and adulthood: the National Longitudinal Study of Adolescent Health. Am J Clin Nutr 2004;80:569–575.[PubMed]
29.
Freedman DS, Khan LK, Serdula MK, et al. The relation of childhood BMI to adult adiposity: the Bogalusa Heart Study. Pediatrics 2005;115:22–27.[PubMed]
30.
Must A, Spadano J, Coakley EH, et al. The disease burden associated with overweight and obesity. JAMA 1999;282:1523–1529.[PubMed]
31.
Baker JL Olsen LW, Sørensen TI. Childhood body-mass index and the risk of coronary heart disease in adulthood. N Engl J Med 2007;357:2329–2337.[PubMed]
32.
Renehan AG, Tyson M, Egger M, et al. Body-mass index and incidence of cancer: a systematic review and meta-analysis of prospective observational studies. Lancet 2008;371:569–578.[PubMed]
33.
Reeves GK, Pirie K, Beral V, et al. Cancer incidence and mortality in relation to body mass index in the Million Women Study: cohort study. BMJ 2007;335:1134.[PubMed]
34.
Tirosh A, Shai I, Afek A, et al. Adolescent BMI trajectory and risk of diabetes versus coronary disease. N Engl J Med 2011;364:1315–1325.[PubMed]
35.
Park MH, Falconer C, Viner RM, et al. The impact of childhood obesity on morbidity and mortality in adulthood: a systematic review. Obes Rev 2012;13:985–1000.[PubMed]
36.
Juonala M, Magnussen CG, Berenson GS, et al. Childhood adiposity, adult adiposity, and cardiovascular risk factors. N Engl J Med 2011;365:1876–1885.[PubMed]
37.
Schwimmer JB, Burwinkle TM, Varni JW. Health-related quality of life of severely obese children and adolescents. JAMA 2003;289:1813–1819.[PubMed]
38.
Flegal KM, Wei R, Ogden CL, et al. Characterizing extreme values of body mass index-for-age by using the 2000 Centers for Disease Control and Prevention growth charts. Am J Clin Nutr 2009;90:1314–1320.[PubMed]
Drukker M, Wojciechowski F, Feron FJ, et al. A community study of psychosocial functioning and weight in young children and adolescents. Int J Pediatr Obes 2009;4:91–97.[PubMed]
39.
Skinner AC, Skelton JA. Prevalence and trends in obesity and severe obesity among children in the United States, 1999-2012. JAMA Pediatr 2014;168:561–566.[PubMed]
Chaiton M, Sabiston C, O'Loughlin J, et al. A structural equation model relating adiposity, psychosocial indicators of body image and depressive symptoms among adolescents. Int J Obes 2009;33:588–596.[PubMed]
40.
Boodhna G. Health Survey for England 2013: Chapter 11, Children’s body mass index, overweight and obesity. 2014. Available at http://www.hscic.gov.uk/catalogue/PUB16076/HSE2013-Ch11-Child-BMI.pdf (last accessed 9 May 2015).
Pitrou I, Shojaei T, Wazana A, et al. Child overweight, associated psychopathology, and social functioning: a French school-based survey in 6- to 11-year-old children. Obesity 2010;18:809–817.[PubMed]
41.
Aikenhead A, Knai C, Lobstein T. Effectiveness and cost-effectiveness of paediatric bariatric surgery: a systematic review. Clin Obes 2011;1:12–25.[PubMed]
42.
Black JA, White B, Viner RM et al. Bariatric surgery for obese children and adolescents: a systematic review and meta-analysis. Obes Rev 2013;14:634–644.[PubMed]
43.
O'Brien PE, Sawyer SM, Laurie C, et al. Laparoscopic adjustable gastric banding in severely obese adolescents: a randomized trial. JAMA 2010;303:519–526.[PubMed]
44.
Michalsky M, Reichard K, Inge T, et al; American Society for Metabolic and Bariatric Surgery (ASMBS). ASMBS Pediatric Committee best practice guidelines. Surg Obes Relat Dis 2012;8:1–7.[PubMed]
45.
Paulus GF, de Vaan LE, Verdam FJ, et al. Bariatric surgery in morbidly obese adolescents: a systematic review and meta-analysis. Obes Surg 2015;25:860–878.[PubMed]
2.
Canoy D, Bundred P. Obesity in children. BMJ Clin Evid 2011;2011.pii:0325.[PubMed]
3.
Whitlock EP, O'Connor EA, Williams SB, et al. Effectiveness of weight management interventions in children: a targeted systematic review for the USPSTF. Pediatrics 2010;125:e396–e418.[PubMed]
4.
US Preventive Services Task Force. Screening for obesity in children and adolescents: US Preventive Services Task Force recommendation statement. Pediatrics 2010;125:361–367.[PubMed]
5.
Agency for Healthcare Research and Quality (AHRQ). Comparative effectiveness of bariatric surgery and nonsurgical therapy in adults with metabolic conditions and a body mass index of 30 to 34.9 kg/m2. September 2013. Available at http://effectivehealthcare.ahrq.gov/ehc/ (last accessed 29 September 2015).[PubMed]
6.
Inge TH, Xanthakos SA, Zeller MH. Bariatric surgery for pediatric extreme obesity: now or later? Int J Obes (Lond) 2007;31:1–14.[PubMed]
7.
National Institute for Health and Care Excellence (NICE). Obesity: identification, assessment and management of overweight and obesity in children, young people and adults. November 2014. Available at https://www.nice.org.uk/guidance/cg189 (last accessed 9 May 2015).
8.
Michalsky MP. Adolescent bariatric surgery in the United Kingdom; a call for continued study and open dialogue. Arch Dis Child 2014;99:885–886.[PubMed]
9.
Kelleher DC, Merrill CT, Cottrell LT, et al. Recent national trends in the use of adolescent inpatient bariatric surgery: 2000 through 2009. JAMA Pediatr 2013;167:126–132.[PubMed]
10.
Bellizzi MC, Dietz WH. Workshop on childhood obesity: summary of the discussion. Am J Clin Nutr 1999;70:173S–175S.[PubMed]
11.
Lobstein T, Baur L, Uauy R. Obesity in children and young people: a crisis in public health. Obes Rev 2004;5(suppl 1):4–104.[PubMed]
12.
Cole TJ, Lobstein T. Extended international (IOTF) body mass index cut-offs for thinness, overweight and obesity. Pediatr Obes 2012;7:284–294.[PubMed]
13.
Ells LJ, Hancock C, Dinsdale H, et al; Public Health England. Severe paediatric obesity: findings from the National Child Measurement Programme. 2013. Available at https://www.noo.org.uk/uploads/doc/vid_18987_ECO_poster_SevereObesityFINAL_v2.pdf (last accessed 9 May 2015).
14.
15.
16.
17.
Cunningham SA, Kramer MR, Narayan KM. Incidence of childhood obesity in the United States. N Engl J Med 2014;370:403–411.[PubMed]
18.
Schwartz MW, Woods SC, Porte D Jr, et al. Central nervous system control of food intake. Nature 2000;404:661–671.[PubMed]
19.
Locke AE, Kahali B, Berndt SI, et al. Genetic studies of body mass index yield new insights for obesity biology. Nature 2015;518:197–206.[PubMed]
20.
Farooqi SI. Genetic, molecular and physiological mechanisms involved in human obesity: Society for Endocrinology Medal Lecture 2012. Clin Endocrinol (Oxf) 2015;82:23–28.[PubMed]
21.
Farooqi S. Insights from the genetics of severe childhood obesity. Horm Res 2007;68(Suppl 5):5–7.[PubMed]
22.
Weinsier RL, Hunter GR, Heini AF, et al. The etiology of obesity: relative contribution of metabolic factors, diet, and physical activity. Am J Med 1998;105:145–150.[PubMed]
Dexter Canoy Cardiovascular Epidemiologist University of Oxford Oxford UK TienYu Owen Yang Epidemiologist University of Oxford Oxford UK Competing interests: DC and TYOY declare that they have no competing interests. We would like to acknowledge the previous contributors of this review, David E. Arterburn and Peter Bundred.
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Disclaimer The information contained in this publication is intended for medical professionals. Categories presented in Clinical Evidence indicate a judgement about the strength of the evidence available to our contributors prior to publication and the relevant importance of benefit and harms. We rely on our contributors to confirm the accuracy of the information presented and to adhere to describe accepted practices. Readers should be aware that professionals in the field may have different opinions. Because of this and regular advances in medical research we strongly recommend that readers' independently verify specified treatments and drugs including manufacturers' guidance. Also, the categories do not indicate whether a particular treatment is generally appropriate or whether it is suitable for a particular individual. Ultimately it is the readers' responsibility to make their own professional judgements, so to appropriately advise and treat their patients. To the fullest extent permitted by law, BMJ Publishing Group Limited and its editors are not responsible for any losses, injury or damage caused to any person or property (including under contract, by negligence, products liability or otherwise) whether they be direct or indirect, special, incidental or consequential, resulting from the application of the information in this publication.
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Obesity in children: bariatric surgery
QUESTIONS What are the effects of surgical interventions for the treatment of childhood obesity?. . . . . . . . . . . . . . . . . . . . . 4 INTERVENTIONS OBESITY IN CHILDREN: SURGICAL INTERVENTIONS Unknown effectiveness
Different types of bariatric surgery versus each other . . 5
Bariatric surgery versus no treatment, usual care, or waiting list control . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Key points • Obesity is the result of long-term energy imbalances, where daily energy intake exceeds daily energy expenditure. Obesity in children is associated with physical as well as psychosocial problems. Long-term adverse health consequences of childhood obesity may include increased risk for chronic disease conditions, including cancer and cardiovascular and metabolic diseases in adulthood. Most obese children stay obese as adults. • Obesity is increasing among children and adolescents, with 16% of boys and 15% of girls in the UK aged 2 to 15 years being obese in 2013. The prevalence of severe obesity is unclear and depends on the classification used to define this condition. However, it has been estimated to be 1% to 4% of children aged 4 to 5 years and 10 to 11 years in the UK in 2011–2012, and up to 8% of children aged 2 to 9 years in the US. • We don't know how effective and safe bariatric surgery is versus no intervention, or different types of bariatric surgery are versus each other, in treating obesity in children, particularly in children with severe obesity, as we found no relevant RCTs. Surgical expertise, specialist care, the target population (i.e., children), and some uncertainties on adverse consequences of bariatric surgery in the long-term are some of the barriers that may have limited the number of RCTs conducted to evaluate the effectiveness and safety of surgical interventions to treat morbid obesity in children. • Future RCTs may require multi-centre collaboration to assess both short-term and long-term follow-up. Findings from existing, well-characterised prospective cohorts of children who underwent bariatric surgery should be relevant, particularly in informing how RCTs should be designed in the future. Future RCTs should also address questions on effectiveness and safety of the different surgical interventions for obesity in children, including the increasingly used technique of laparoscopic sleeve gastrectomy. Clinical context
GENERAL BACKGROUND The prevalence of overweight children and childhood obesity remains high in the UK and in many countries worldwide. Lifestyle interventions form part of the main strategy to treat childhood obesity; however, the impact of these interventions is limited, particularly in morbidly obese children.There is a growing interest in the use of surgical interventions in the treatment and management of obesity in paediatric patients, but evidence for the benefits and harms of surgical interventions is unclear, and the cost-effectiveness of this intervention is unknown.
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Clinical Evidence 2015;10:325
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The main purpose of this overview is to seek evidence from RCTs to assess physical, psychosocial, and quality-oflife outcomes of bariatric surgery in childhood obesity as compared to appropriate control (no intervention, usual care, or waiting list control), or of different types of bariatric surgery compared with each other.
COMMENTS ON EVIDENCE Two systematic reviews met our criteria. However, these reviews included mostly non-RCTs and studies without appropriate comparison groups. Some of the barriers that may have limited the number of RCTs conducted to evaluate the effectiveness and safety of surgical interventions to treat morbid obesity in children include: surgical expertise, specialist care, the target population (i.e., children), and some uncertainties on adverse consequences of bariatric surgery in the long term.
SEARCH AND APPRAISAL SUMMARY The update literature search for this review was carried out from the date of the last search, January 2010, to August 2014. For more information on the electronic databases searched and criteria applied during assessment of studies for potential relevance to the overview, please see the Methods section. After deduplication and removal of conference abstracts, 67 records were screened for inclusion in the overview. Appraisal of titles and abstracts led to the exclusion of 19 studies and the further review of 48 full publications. Of the 48 full articles evaluated, two systematic reviews were included at this update.
ADDITIONAL INFORMATION Lifestyle interventions, usually delivered through behavioural programmes, may be effective in reducing excess [1] [2] [3] [4] [5] weight in obese children, but these interventions may have limited impact in children with severe [1] [6] obesity. Even if weight loss is achieved through lifestyle modification, the magnitude of the effect is small and severely obese children remain obese (please see the previous version of this overview where we have considered the evidence for lifestyle interventions). The indication and patient selection criteria for bariatric surgery remain poorly defined, but the target patient group in paediatric populations is likely to be limited to older children with severe obesity (e.g., adolescents). Bariatric surgery may be offered as a treatment option for morbidly obese children, but [1] [7] is usually reserved for exceptional circumstances in settings where this treatment is available and accessible. There is growing interest in the use of bariatric surgery as a treatment option for obesity among paediatric patients, [1] [6] [8] [9] but the evidence for the effectiveness and safety of such surgical intervention is unclear. DEFINITION
Obesity is a chronic condition characterised by an excess of body fat that presents a risk to health. Body mass index (BMI), calculated as weight (in kilograms) divided by squared height (in metres), is a crude yet simple and widely used measure in the identification of overweight and obesity as it [10] is highly correlated with body fat. In young children and adolescents, BMI varies with age and sex. It typically rises during the first months after birth, falls after the first year, and rises again [11] around the sixth year of life and into adolescence. Thus, a child's BMI is usually compared to age- and sex-specific BMI of a reference population to obtain the BMI percentile of the child relative to that population. A BMI above the 95th percentile is variably defined as obese, which generally indicates a need for intervention. A small subgroup of obese children are considered to have severe obesity (also described as extreme or morbid obesity), but there is no standard definition to identify this group, and their classification is largely based on the very extreme end of the BMI percentile 2 distribution, or the BMI percentile distribution equivalent to the adult BMI of 35 kg/m or higher [1] [12] [13] [14] [15] (class II and III obesity).
INCIDENCE/ PREVALENCE
The prevalence of obesity (generally, BMI >95th percentile) has been increasing among children and adolescents. In the UK in 2013, it was estimated that 16% of boys and 15% of girls aged 2 to 15 years were obese, an increase from 11% of boys and 12% of girls in 1995, but a decrease from [16] 18% to 19% of both boys and girls from when the prevalence peaked in 2004 and 2005. This pattern suggested an increasing prevalence of obesity until the mid-2000s, when the prevalence seemed to have plateaued. Among children followed for more than 9 years from age 5, 12% became obese when they reached age 14 years, with an incidence rate of 26.5 per 1000 person-years [17] among non-obese at baseline. The proportion of extremely obese children varies with the classification used. In the National Child Measurement Programme in England in 2011 to 2012, around 2% of children 4 to 5 years old and 3% to 4% of those 10 to 11 years old had severe obesity, based on classifying severe obesity as equal to or above the 99.6th percentile on the UK 1990 growth chart; or 1% to 2% of children 4 to 5 years old and 1% of those 10 to 11 years old when [13] using the International Obesity Task Force classification. The prevalence of severe obesity among 4- to 5-year-olds hardly changed between 2006–2007 and 2011–2012, but there was a marked increase over the same period among 10- to 11-year-olds. In the US, little has changed in the prevalence of overweight children, but the proportions of obese, as well as severely obese, [15] children continued to rise between 1999–2000 and 2011–2012. In 2011–2012, up to 8% of [1] [15] children in the US aged 2 to 19 years may be considered to be severely obese.
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[18]
AETIOLOGY/ Obesity is the result of disproportionate energy consumption outweighing energy expenditure. [19] [20] RISK FACTORS The genetic basis of obesity has been well investigated, and genetic factors are likely to [21] play an important role in the aetiology of severe obesity. However, the increase in obesity prevalence in the past few decades is less likely to be explained by changes in the human gene pool, and more likely to be related to environmental changes that promote excessive food intake [22] [23] [24] and discourage physical activity (increasing sedentariness); and changes to other distal factors that may influence diet and physical activity, including parental education, social de[11] [25] privation, infant feeding patterns, and intrauterine exposures. Physical activity levels have decreased over the years. Only 36% of children and adolescents in the US meet the recommended [26] levels of physical activity. Among British children aged 5 to 15 years in 2012, only 21% of boys and 16% of girls met the minimum physical activity level required to achieve health benefits, down [27] from 28% of boys and 19% of girls in 2008. Less commonly, obesity may also be induced by drugs (e.g., high-dose glucocorticoids), neuroendocrine disorders (e.g., Cushing's syndrome), or [11] inherited disorders (e.g., Down's syndrome and Prader-Willi syndrome). PROGNOSIS
Most obese children will become obese adolescents. Obese children at age 5 years are four times [17] more likely to become obese at age 14 years than non-obese children. In longitudinal studies, most obese children and adolescents are also most likely to become obese adults as compared [28] [29] to non-obese children. Consequently, the obese children who remain obese in adulthood develop adverse morbidity and mortality outcomes later in life, including hypertension, dyslipidaemia, [11] [30] [31] diabetes, cardiovascular disease, sleep apnoea, osteoarthritis, and some cancers. [32] [33] [34] [35] The long-term adverse health risks associated with childhood obesity are potentially modifiable. The effect of childhood obesity on adult health outcomes is generally linked to the [35] development of a high adult BMI among obese children later in life. The associated risks are [36] reduced if these children achieve normal weight when they reach adulthood. Perhaps a less recognised but important short-term comorbidity of overweight/obesity, particularly in adolescent children, is functional impairment in several psychosocial domains, including social marginalisation, [11] [37] [38] [39] [40] low self-esteem, and impaired quality of life.
AIMS OF To achieve reduction in BMI and BMI percentile, and to prevent the morbidity and mortality associINTERVENTION ated with obesity, without undue adverse effects. OUTCOMES
Change in overweight proxy measures assessed in studies included mean weight loss (kg), 2 change in BMI (kg/m ), change in BMI z score, change in BMI percentile, change in percentage overweight, obesity or severe obesity, and change in other adiposity indicators (waist circumference, hip circumference, waist-hip ratio, total fat mass, percentage fat mass); mortality (associated with obesity); quality of life; secondary disease outcome any change in diabetes (diagnosis of diabetes, change in treatment for diabetes, change in fasting insulin or glucose levels), hypertension (diagnosis of hypertension, change in treatment for hypertension, change in blood pressure), dyslipidaemia (diagnosis of dyslipidaemia, change in treatment of dyslipidaemia, change in total or LDL-cholesterol); adverse effects.
METHODS
Search strategy BMJ Clinical Evidence search and appraisal August 2014. Databases used to identify studies for this systematic review include: Medline 1966 to August 2014, Embase 1980 to August 2014, The Cochrane Database of Systematic Reviews 2014, issue 3 (1966 to date of issue), the Database of Abstracts of Reviews of Effects (DARE), and the Health Technology Assessment (HTA) database. Inclusion criteria Study design criteria for inclusion in this systematic overview were systematic reviews and RCTs published in English and containing 10 or more individuals (at least 5 people per study arm), of whom more than 60% were followed up. RCTs could be open or blinded. Minimum length of follow-up was 12 weeks. We included studies in overweight and obese children (aged 18 years and younger), including children with a BMI above the 85th percentile for age and sex. We included RCTs and systematic reviews of RCTs where harms of an included intervention were assessed, applying the same study design criteria for inclusion as we did for benefits. BMJ Clinical Evidence does not necessarily report every study found (e.g., every systematic review). Rather, we report the most recent, relevant and comprehensive studies identified through an agreed process involving our evidence team, editorial team, and expert contributors. Evidence evaluation A systematic literature search was conducted by our evidence team, who then assessed titles and abstracts, and finally selected articles for full text appraisal against inclusion and exclusion criteria agreed a priori with our expert contributors. In consultation with the expert contributors, studies were selected for inclusion and all data relevant to this overview extracted into the benefits and harms section of the overview. In addition, information that did not meet our predefined criteria for inclusion in the benefits and harms section, may have been reported in the 'Further information on studies' or 'Comment' section. Adverse effects All serious adverse effects, or those adverse effects reported as statistically significant, were included in the harms section of the overview. Prespecified adverse effects identified as being clinically important were also reported, even if the results
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were not statistically significant. Although BMJ Clinical Evidence presents data on selected adverse effects reported in included studies, it is not meant to be, and cannot be, a comprehensive list of all adverse effects, contraindications, or interactions of included drugs or interventions. A reliable national or local drug database must be consulted for this information. Comment and Clinical guide sections In the Comment section of each intervention, our expert contributors may have provided additional comment and analysis of the evidence, which may include additional studies (over and above those identified via our systematic search) by way of background data or supporting information. As BMJ Clinical Evidence does not systematically search for studies reported in the Comment section, we cannot guarantee the completeness of the studies listed there or the robustness of methods. Our expert contributors add clinical context and interpretation to the Clinical guide sections where appropriate. Structural changes this update At this update, we have removed the following previously reported question: What are the effects of lifestyle interventions for the treatment of childhood obesity? Data and quality To aid readability of the numerical data in our reviews, we round many percentages to the nearest whole number. Readers should be aware of this when relating percentages to summary statistics such as relative risks (RRs) and odds ratios (ORs). BMJ Clinical Evidence does not report all methodological details of included studies. Rather, it reports by exception any methodological issue or more general issue that may affect the weight a reader may put on an individual study, or the generalisability of the result. These issues may be reflected in the overall GRADE analysis. QUESTION
What are the effects of surgical interventions for the treatment of childhood obesity?
OPTION
BARIATRIC SURGERY VERSUS NO TREATMENT, USUAL CARE, OR WAITING LIST CONTROL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
•
We found no direct information from RCTs on the effects of bariatric surgery versus no treatment, usual care, or waiting list controls for obesity in children.
•
Although bariatric surgery could potentially result in substantial weight loss among severely obese adolescents, evidence from well designed studies, particularly from RCTs, is limited. Uncertainties remain regarding clinical indications, identification of the relevant age group, cost, ethics, post-operative complications, and the short- and long-term benefits and harms of surgical procedures in this population. Benefits and harms
Bariatric surgery versus no treatment, usual care, or waiting list control: We found two systematic reviews (search dates 2010; and 2013) evaluating the effects of bariatric surgery for obe[41] [42] sity in children. The reviews included mostly non-RCTs, and did not identify any RCT comparing bariatric surgery with no treatment, usual care, or waiting list control. We found no additional or subsequent RCTs. Comment:
Findings from the review of mostly non-RCTs suggest that surgical intervention in the treatment of severe obesity could lead to a substantial amount of weight loss. However, the actual magnitude of weight loss is unclear. In one RCT, laparoscopic adjustable gastric banding resulted in substantial [43] weight loss when compared to an intensive lifestyle intervention, suggesting that, if the comparison group was given usual or conventional care for obese children, the magnitude of the effect could have been potentially greater in this study. However, the evidence for the effectiveness and safety of surgical interventions for the treatment of paediatric obesity remains poor. Uncertainties remain, particularly in relation to indications, patient selection criteria, post-operative complications, and beneficial and harmful outcomes beyond weight loss in the short and long term. How long is 'long term' to assess benefits and harms associated with surgical interventions for obesity in paediatric populations needs further elucidation considering that, depending on the age at surgical intervention, a 24-month follow-up would still mean assessing outcomes during childhood for some patients. There are registered RCTs (e.g., ClinicalTrials.gov identifiers NCT01700738 and NCT02378259), but the status of these trials is unclear as they are probably not actively recruiting patients into the study. Surgical expertise, specialist care, the target population (i.e., children), and some uncertainties on adverse consequences of bariatric surgery in the long-term are some of the barriers that may have limited the number of RCTs conducted to evaluate the effectiveness and safety of surgical interventions to treat morbid obesity in children. Future RCTs may require multi-centre collaboration to
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assess both short-term and long-term follow-up. Findings from existing, well-characterised prospective cohorts of children who underwent bariatric surgery should be relevant, particularly in [44] informing how RCTs should be designed in the future. Future RCTs should also address questions regarding the effectiveness and safety of the different surgical interventions for obesity in children, including the increasingly used technique of laparoscopic sleeve gastrectomy. Clinical guide Surgical treatment strategies for paediatric obesity are complex and may only be used in exceptional circumstances. Unlike in adults, there are several considerations that are specific to paediatric populations, including potential effects on growth and development, having a longer lifespan than adults to experience benefits and harms, and issues of consent. However, factors such as the local healthcare system and availability of specialist services are key considerations for surgical interventions for childhood obesity. As in adults, the magnitude of weight loss after bariatric surgery is likely to be substantial and could lead to improvements in cardiovascular and metabolic risk profile, at least in the short term. However, this treatment strategy for obesity is likely to be limited to severe obesity in paediatric patients who have reached appropriate chronological age and/or developmental stage, and only after other conventional weight management approaches have been explored. In addition, the absolute long-term benefits and harms of surgical treatment in this population are currently poorly described and quantified. OPTION
DIFFERENT TYPES OF BARIATRIC SURGERY VERSUS EACH OTHER. . . . . . . . . . . . . . . . . .
•
We found no direct information from RCTs on the effects of different types of bariatric surgery for obesity in children.
•
There are different bariatric surgery techniques that have been used to treat severe obesity in adolescence. One of the key considerations to the technique of choice is the reversibility or permanence of the procedure on the intestinal tract. We found no RCTs comparing the effectiveness between surgical techniques or evaluating the benefits and harms of the different bariatric surgery techniques. Benefits and harms
Different types of bariatric surgery versus each other: We found no systematic review or RCTs comparing different types of bariatric surgery with each other in children that met our inclusion criteria. Comment:
Clinical guide As in adults, laparoscopic adjustable gastric banding and the Roux-en-Y gastric bypass are two of the most commonly used procedures for surgical intervention in children with severe obesity, although laparoscopic sleeve gastrectomy has been increasingly used in some medical centres. However, there are no RCTs comparing the effectiveness of different surgical techniques in treating severe obesity. Observations from mostly non-RCTs suggest substantial reduction in BMI using the three surgical techniques, with the biggest reductions in BMI seen after Roux-en-Y gastric bypass [45] procedures. However, the evidence has been based on studies without appropriate comparison groups and with heterogeneity in the patient selection criteria, definition of severe obesity, and sample size. One of the key considerations for the procedure of choice is the reversibility or permanence of the procedure on the intestinal tract. However, the use of adjustable gastric banding in people under 18 years of age is currently not approved by the FDA and is usually performed 'offlabel'.
GLOSSARY Z score The z score reveals how many units of the standard deviation a case is above or below the mean.
SUBSTANTIVE CHANGES Bariatric surgery versus no treatment, usual care, or waiting list control Option restructured. Two systematic [41] [42] reviews added. Categorised as 'unknown effectiveness'. Different types of bariatric surgery versus each other Option restructured. No new evidence. Categorised as 'unknown effectiveness'.
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REFERENCES 1.
Kelly AS, Barlow SE, Rao G, et al; American Heart Association Atherosclerosis, Hypertension, and Obesity in the Young Committee of the Council on Cardiovascular Disease in the Young, Council on Nutrition, Physical Activity and Metabolism, and Council on Clinical Cardiology. Severe obesity in children and adolescents: identification, associated health risks, and treatment approaches: a scientific statement from the American Heart Association. Circulation 2013;128:1689–1712.[PubMed]
23.
French SA, Story M, Jeffery RW. Environmental influences on eating and physical activity. Annu Rev Public Health 2001;22:309–335.[PubMed]
24.
Lobstein T, Jackson-Leach R, Moodie ML, et al. Child and adolescent obesity: part of a bigger picture. Lancet 2015 Feb 18 [Epub ahead of print].[PubMed]
25.
Katzmarzyk PT, Barlow S, Bouchard C, et al. An evolving scientific basis for the prevention and treatment of pediatric obesity. Int J Obes (Lond) 2014;38:887–905.[PubMed]
26.
Eaton DK, Kann L, Kinchen S, et al. Youth risk behavior surveillance – United States, 2005. MMWR Surveill Summ 2006;55:1–108.[PubMed]
27.
Health and Social Care Information Centre. Health survey for England - 2013, trend tables. December 2014. Available at http://www.hscic.gov.uk/catalogue/PUB16077 (last accessed 9 May 2015).
28.
Gordon-Larsen P, Adair LS, Nelson MC, et al. Five-year obesity incidence in the transition period between adolescence and adulthood: the National Longitudinal Study of Adolescent Health. Am J Clin Nutr 2004;80:569–575.[PubMed]
29.
Freedman DS, Khan LK, Serdula MK, et al. The relation of childhood BMI to adult adiposity: the Bogalusa Heart Study. Pediatrics 2005;115:22–27.[PubMed]
30.
Must A, Spadano J, Coakley EH, et al. The disease burden associated with overweight and obesity. JAMA 1999;282:1523–1529.[PubMed]
31.
Baker JL Olsen LW, Sørensen TI. Childhood body-mass index and the risk of coronary heart disease in adulthood. N Engl J Med 2007;357:2329–2337.[PubMed]
32.
Renehan AG, Tyson M, Egger M, et al. Body-mass index and incidence of cancer: a systematic review and meta-analysis of prospective observational studies. Lancet 2008;371:569–578.[PubMed]
33.
Reeves GK, Pirie K, Beral V, et al. Cancer incidence and mortality in relation to body mass index in the Million Women Study: cohort study. BMJ 2007;335:1134.[PubMed]
34.
Tirosh A, Shai I, Afek A, et al. Adolescent BMI trajectory and risk of diabetes versus coronary disease. N Engl J Med 2011;364:1315–1325.[PubMed]
35.
Park MH, Falconer C, Viner RM, et al. The impact of childhood obesity on morbidity and mortality in adulthood: a systematic review. Obes Rev 2012;13:985–1000.[PubMed]
36.
Juonala M, Magnussen CG, Berenson GS, et al. Childhood adiposity, adult adiposity, and cardiovascular risk factors. N Engl J Med 2011;365:1876–1885.[PubMed]
37.
Schwimmer JB, Burwinkle TM, Varni JW. Health-related quality of life of severely obese children and adolescents. JAMA 2003;289:1813–1819.[PubMed]
38.
Flegal KM, Wei R, Ogden CL, et al. Characterizing extreme values of body mass index-for-age by using the 2000 Centers for Disease Control and Prevention growth charts. Am J Clin Nutr 2009;90:1314–1320.[PubMed]
Drukker M, Wojciechowski F, Feron FJ, et al. A community study of psychosocial functioning and weight in young children and adolescents. Int J Pediatr Obes 2009;4:91–97.[PubMed]
39.
Skinner AC, Skelton JA. Prevalence and trends in obesity and severe obesity among children in the United States, 1999-2012. JAMA Pediatr 2014;168:561–566.[PubMed]
Chaiton M, Sabiston C, O'Loughlin J, et al. A structural equation model relating adiposity, psychosocial indicators of body image and depressive symptoms among adolescents. Int J Obes 2009;33:588–596.[PubMed]
40.
Boodhna G. Health Survey for England 2013: Chapter 11, Children’s body mass index, overweight and obesity. 2014. Available at http://www.hscic.gov.uk/catalogue/PUB16076/HSE2013-Ch11-Child-BMI.pdf (last accessed 9 May 2015).
Pitrou I, Shojaei T, Wazana A, et al. Child overweight, associated psychopathology, and social functioning: a French school-based survey in 6- to 11-year-old children. Obesity 2010;18:809–817.[PubMed]
41.
Aikenhead A, Knai C, Lobstein T. Effectiveness and cost-effectiveness of paediatric bariatric surgery: a systematic review. Clin Obes 2011;1:12–25.[PubMed]
42.
Black JA, White B, Viner RM et al. Bariatric surgery for obese children and adolescents: a systematic review and meta-analysis. Obes Rev 2013;14:634–644.[PubMed]
43.
O'Brien PE, Sawyer SM, Laurie C, et al. Laparoscopic adjustable gastric banding in severely obese adolescents: a randomized trial. JAMA 2010;303:519–526.[PubMed]
44.
Michalsky M, Reichard K, Inge T, et al; American Society for Metabolic and Bariatric Surgery (ASMBS). ASMBS Pediatric Committee best practice guidelines. Surg Obes Relat Dis 2012;8:1–7.[PubMed]
45.
Paulus GF, de Vaan LE, Verdam FJ, et al. Bariatric surgery in morbidly obese adolescents: a systematic review and meta-analysis. Obes Surg 2015;25:860–878.[PubMed]
2.
Canoy D, Bundred P. Obesity in children. BMJ Clin Evid 2011;2011.pii:0325.[PubMed]
3.
Whitlock EP, O'Connor EA, Williams SB, et al. Effectiveness of weight management interventions in children: a targeted systematic review for the USPSTF. Pediatrics 2010;125:e396–e418.[PubMed]
4.
US Preventive Services Task Force. Screening for obesity in children and adolescents: US Preventive Services Task Force recommendation statement. Pediatrics 2010;125:361–367.[PubMed]
5.
Agency for Healthcare Research and Quality (AHRQ). Comparative effectiveness of bariatric surgery and nonsurgical therapy in adults with metabolic conditions and a body mass index of 30 to 34.9 kg/m2. September 2013. Available at http://effectivehealthcare.ahrq.gov/ehc/ (last accessed 29 September 2015).[PubMed]
6.
Inge TH, Xanthakos SA, Zeller MH. Bariatric surgery for pediatric extreme obesity: now or later? Int J Obes (Lond) 2007;31:1–14.[PubMed]
7.
National Institute for Health and Care Excellence (NICE). Obesity: identification, assessment and management of overweight and obesity in children, young people and adults. November 2014. Available at https://www.nice.org.uk/guidance/cg189 (last accessed 9 May 2015).
8.
Michalsky MP. Adolescent bariatric surgery in the United Kingdom; a call for continued study and open dialogue. Arch Dis Child 2014;99:885–886.[PubMed]
9.
Kelleher DC, Merrill CT, Cottrell LT, et al. Recent national trends in the use of adolescent inpatient bariatric surgery: 2000 through 2009. JAMA Pediatr 2013;167:126–132.[PubMed]
10.
Bellizzi MC, Dietz WH. Workshop on childhood obesity: summary of the discussion. Am J Clin Nutr 1999;70:173S–175S.[PubMed]
11.
Lobstein T, Baur L, Uauy R. Obesity in children and young people: a crisis in public health. Obes Rev 2004;5(suppl 1):4–104.[PubMed]
12.
Cole TJ, Lobstein T. Extended international (IOTF) body mass index cut-offs for thinness, overweight and obesity. Pediatr Obes 2012;7:284–294.[PubMed]
13.
Ells LJ, Hancock C, Dinsdale H, et al; Public Health England. Severe paediatric obesity: findings from the National Child Measurement Programme. 2013. Available at https://www.noo.org.uk/uploads/doc/vid_18987_ECO_poster_SevereObesityFINAL_v2.pdf (last accessed 9 May 2015).
14.
15.
16.
17.
Cunningham SA, Kramer MR, Narayan KM. Incidence of childhood obesity in the United States. N Engl J Med 2014;370:403–411.[PubMed]
18.
Schwartz MW, Woods SC, Porte D Jr, et al. Central nervous system control of food intake. Nature 2000;404:661–671.[PubMed]
19.
Locke AE, Kahali B, Berndt SI, et al. Genetic studies of body mass index yield new insights for obesity biology. Nature 2015;518:197–206.[PubMed]
20.
Farooqi SI. Genetic, molecular and physiological mechanisms involved in human obesity: Society for Endocrinology Medal Lecture 2012. Clin Endocrinol (Oxf) 2015;82:23–28.[PubMed]
21.
Farooqi S. Insights from the genetics of severe childhood obesity. Horm Res 2007;68(Suppl 5):5–7.[PubMed]
22.
Weinsier RL, Hunter GR, Heini AF, et al. The etiology of obesity: relative contribution of metabolic factors, diet, and physical activity. Am J Med 1998;105:145–150.[PubMed]
Dexter Canoy Cardiovascular Epidemiologist University of Oxford Oxford UK TienYu Owen Yang Epidemiologist University of Oxford Oxford UK Competing interests: DC and TYOY declare that they have no competing interests. We would like to acknowledge the previous contributors of this review, David E. Arterburn and Peter Bundred.
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Disclaimer The information contained in this publication is intended for medical professionals. Categories presented in Clinical Evidence indicate a judgement about the strength of the evidence available to our contributors prior to publication and the relevant importance of benefit and harms. We rely on our contributors to confirm the accuracy of the information presented and to adhere to describe accepted practices. Readers should be aware that professionals in the field may have different opinions. Because of this and regular advances in medical research we strongly recommend that readers' independently verify specified treatments and drugs including manufacturers' guidance. Also, the categories do not indicate whether a particular treatment is generally appropriate or whether it is suitable for a particular individual. Ultimately it is the readers' responsibility to make their own professional judgements, so to appropriately advise and treat their patients. To the fullest extent permitted by law, BMJ Publishing Group Limited and its editors are not responsible for any losses, injury or damage caused to any person or property (including under contract, by negligence, products liability or otherwise) whether they be direct or indirect, special, incidental or consequential, resulting from the application of the information in this publication.
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