DIABETICMedicine DOI: 10.1111/dme.12494
Systematic Review or Meta-analysis Diabetes in people with an intellectual disability: a systematic review of prevalence, incidence and impact K. McVilly1, J. McGillivray1, A. Curtis1, J. Lehmann3, L. Morrish1 and J. Speight1,2,4 1 Deakin University, School of Psychology and Centre for Mental Health and Wellbeing Research, Burwood, Victoria, 2The Australian Centre for Behavioural Research in Diabetes, Diabetes Australia, Melbourne, Victoria, 3EdHealth Australia, Malvern, South Australia, Australia and 4AHP Research, Hornchurch, UK
Accepted 9 May 2014
Abstract Aims To establish the prevalence and incidence of Type 1 and Type 2 diabetes in people with an intellectual and developmental disability and determine their impact on health and well-being and to appraise the evidence available to inform good practice in diabetes management for people with intellectual and developmental disabilities. Methods We conducted separate searches of multiple databases (EMBASE, CINAHL, MEDLINE, PsycINFO, SCOPUS, Web of Science, PUBMED and Cochrane Library) to find relevant articles.
A total of 13 studies were identified: 13 addressed the prevalence of diabetes in people with intellectual and developmental disability, three addressed the impact of diabetes on their health and well-being and three addressed the management of diabetes. The prevalence of diabetes in people with intellectual and developmental disability remains uncertain, and the incidence of diabetes in this group of people is unknown. There is some evidence to support the assertion that people with intellectual and developmental disability might be at greater risk of diabetes than the general population. Overall, the quality of the evidence on which to base prevention and management strategies is variable.
Results
Conclusions There is a paucity of research focusing on the prevalence, incidence and impact of diabetes among people with intellectual and developmental disability. Further research is needed to inform policy and practice in this area and, in particular, work is needed to develop methodologies, evaluation tools, educational resources and diabetes care support services appropriate to the needs of people with intellectual and developmental disability.
Diabet. Med. 31, 897–904 (2014)
Introduction People with intellectual and developmental disability (IDD) comprise 1–3% of the population [1,2], with higher rates in communities characterised by poverty [3–5]. People with IDD are high-frequency users of health services, presenting with multiple comorbidities [3,6,7] and earlier manifestation compared with people without IDD, and this is confounded by a combination of genetic, personal and socio-economic factors [4,5]. People with IDD are at higher risk of Type 2 diabetes, which is attributed to obesity, reduced physical activity, elevated blood pressure and poor nutrition [8–10]. Identifying the prevalence of Type 1 diabetes in people with IDD is difficult, as they are sometimes excluded from studies for logistical reasons (e.g. communication difficulties) or their co-existing disability is not recognised or recorded; however, where co-existing IDD has been recognized, a greater prevalence has been observed in people with autism Correspondence to: Keith McVilly. E-mail: [email protected]
ª 2014 The Authors. Diabetic Medicine ª 2014 Diabetes UK
[6,14] and those with Down’s syndrome [9,10] than in the general population. The prevalence of Type 1 diabetes in people with Down’s syndrome in Denmark was identified as being four times that of all children born in Denmark in 1981–2000 [11]. In Scotland, the prevalence of Type 1 diabetes in people with Down’s syndrome is estimated at 10.6%, or 10 times greater than in the general population [12]. This higher prevalence of Type 1 diabetes among people with Down’s syndrome should be a matter of concern, given that diabetes can account for 3% of deaths annually in the general population [15]. Furthermore, diabetes-related morbidity and mortality has been identified as a particular concern for people with IDD, including those with autism [7,8]. Optimum diabetes management requires considerable self-care involving a number of practical tasks, e.g. choosing appropriate foods and portion sizes, monitoring and interpreting blood glucose levels, being physically active and taking medication [16]. People with IDD experience challenges with such tasks [1], and can be overwhelmed by them
897
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Diabetes and people with intellectual disability K. McVilly et al.
[17]. Consequently, they rely on the support of others [1]. An emerging literature suggests that for many people with IDD, optimum diabetes care is not achieved [8,18–20]. Given the detrimental impact of persistently elevated blood glucose levels, including the development of complications, increased hospitalizations and length of hospital stay, reduced quality of life, and increased health expenditure [21], appropriate management and education in self- or supported care in people with IDD is crucial [22]. The apparent shortcomings in diabetes-related care might reflect: broader unmet healthcare needs among people with IDD [24–26]; complications associated with detecting pain [27]; diagnostic overshadowing [28]; comparatively low rates of participation in health screening and health promotion [26,29]; and insufficient training of health professionals in how to relate to, communicate with and adapt health service provision for people with IDD [18,25]. Overall, however, it is evident that diabetes management in people with IDD should be a matter of concern for policy makers, healthcare professionals and educators. Our aim therefore was to conduct a systematic review of the evidence base underpinning good practice in diabetes detection and management for people with IDD. Our questions were: (1) What is known about the prevalence and incidence of Type 1 diabetes and Type 2 diabetes in people with IDD?; (2) What is known about the impact of diabetes on the physical health and psychological wellbeing of people with IDD?; and (3) How is diabetes managed in people with IDD, and what is known about the quality of care and the degree to which people are supported to self-manage their condition?
diabetes with the addition of impact* or ‘well being’ or ‘well-being’ or ‘wellbeing’ or ‘quality of life’. Research Question 3: the terms concerning IDD and diabetes again remained the same, with the addition of: ‘self manag*’ or ‘self-manag*’ or manag*. The reference lists of relevant articles were also reviewed to identify further relevant articles. Titles and abstracts were reviewed manually to determine if they met the following inclusion criteria: (1) the paper was specific to both IDD and diabetes, and addressed at least one of the research questions; (2) participants were adults; (3) the paper had been peer-reviewed; and (4) the paper was not a duplicate of a previous paper. The exclusion criteria required the removal of articles that did not incorporate both intellectual disability (and its equivalents) and diabetes. Experimental research (e.g. investigating glucose manipulation and glucose tolerance) was deemed to be outside the scope of the present review, which had a clinical focus. There were no relevant articles in any language other than English. Articles were summarized and their quality appraised using the Systematic Review Appraisal form [30]. The appraisal tool was informed by quality criteria recommended by the Social Care Institute for Excellence [31], the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) [49], and the Effective Public Health Practice Project, as described by Thomas et al. [33]. The tool used nine quality domains: reference to the literature; having a research focus; having ethics approval; providing details of the method and procedures; describing the participants; describing the tools used; details of the data analysis; details of the findings; discussion of results and implications of the findings; and supporting references. Ratings were conducted according to a three-point scale (0, 1 or 2), with a total possible score of 18. Ratings were made on the basis of group consensus.
Methods We conducted separate searches of multiple databases (EMBASE, CINAHL, MEDLINE, PsycINFO, SCOPUS, Web of Science, PUBMED and Cochrane Library) for each of the questions listed below (the most recent on 29th April 2013). The key search terms for each research question are as follows. Research Question 1: ‘intellectual* disabil*’ or ‘mental retardation’ or ‘intellectual* impair*’ or ‘learning disabil*’ or ‘developmental disabil*’ and diabet* and prevalen* and/or inciden*. Diabetes mellitus was considered the focus of the current review. Consequently, conditions identified as pre-diabetic states, or as difficulties with glucose metabolism more generally, although not necessarily excluded from the search, were not the focus of specific searches in their own right. Syndrome-specific searches were not conducted, as the diversity of options was considered too great and there was no established evidence base to focus any such search. It is reasonable, however, to conclude that syndrome-specific research in this population would typically make reference to the broader term IDD and the related terms included in the current search strategy. Research Question 2: the same terms were used in regard to IDD and
898
Results Prevalence and incidence of diabetes in people with intellectual and developmental disability
The initial search discovered 1233 abstracts, which were screened against the inclusion criteria. After removing duplicates and articles not meeting the review criteria, 72 articles remained. Each was read in depth to determine its suitability for inclusion, specifically based on whether it reported prevalence or incidence rates for diabetes in people with IDD. A total of 13 studies were identified (Fig. 1).
Impact of diabetes on health and well-being among people with an intellectual and developmental disability
The initial search discovered 560 articles, which were further reviewed against the inclusion criteria, as described above. After removing duplicates and articles not meeting the review
ª 2014 The Authors. Diabetic Medicine ª 2014 Diabetes UK
Systematic Review or Meta-analysis
Queson 1 - Prevalence: 1233 abstracts returned by search
DIABETICMedicine
Queson 2 - Impact: 560 abstracts returned by search
1161 abstracts excluded. Reasons: -Duplicate - Irrelevant
72 full-text arcles reviewed
4278 abstracts excluded.
Reasons:
Reasons:
-Duplicate
-Duplicate
- Irrelevant
- Irrelevant
16 arcles excluded.
Reasons:
-Did not include both IDD & diabetes
- Did not report prevalence or incidence stascs
11 full-text arcles reviewed
8 arcles excluded. Reasons:
Reasons:
-Did not include both IDD & diabetes
13 studies included in review
541 abstracts excluded.
19 full-text arcles reviewed
58 arcles excluded.
Queson 3 - Management: 4289 abstracts returned by search
- Did not report on the impact of diabetes on people with IDD
3 studies included in review
-Did not include both IDD & diabetes - Did not report on the selfmanagement of diabetes in people with IDD
3 studies included in review
FIGURE 1 Flow chart of search strategy and results for research questions on the prevalence, impact and management of diabetes in people with intellectual and developmental disability.
criteria, 19 articles were identified. Each was read in depth to determine its suitability for inclusion, based on whether it reported the impact (on physical or psychological health, and well-being) of diabetes on people with IDD. Three studies were identified (Fig. 1).
Management of diabetes by people with intellectual and developmental disability
The initial search discovered 4289 articles. After removing duplicates and articles not meeting the review criteria, 11 articles remained. Each was read in depth to determine its suitability for inclusion, based on whether it reported on the self-management of diabetes in people with IDD. Three studies were identified (Fig. 1). The articles identified as addressing each of the three research questions are summarized in the supplementary online tables (Tables S1–3). The tables are organized according to country of origin, aims and research questions, category of paper, ethics approval, overall design/methodology, participants, type of diabetes, measures/analysis, findings and the quality rating for each article based on the Systematic Review Appraisal Form [30].
Study characteristics and quality appraisal Prevalence and incidence of diabetes in people with intellectual and developmental disability
None of the studies reported the incidence of diabetes in people with IDD. Prevalence was reported in 13 studies
ª 2014 The Authors. Diabetic Medicine ª 2014 Diabetes UK
(Table S1). Generally, the statistical data reported were limited (i.e. there was an absence of confidence intervals and effect sizes). In addition, none of the studies distinguished between Type 1 diabetes and Type 2 diabetes in the reporting of prevalence and none made reference to gestational diabetes. Assessment of prevalence in the included studies was made using a range of methods, including data extraction from medical records [32–36], survey [26,37–40], interview [41], and physical examination [21,42,43]. The largest study comprised 27 116 participants [37], while the smallest comprised four participants [17]. All studies included people with mild and moderate IDD, with three including those with severe and profound IDD. Co-existing conditions included cerebral palsy and Down’s syndrome. The average age of participants was 46 years (excluding three studies in which age was not reported); the youngest mean age was 35.4 years [21] and oldest 61.5 years [32]. Six studies were conducted in the USA [21,33–37,43], three in the Netherlands [32,41,44], and one each in Hong Kong [38], China [42], Europe [39] and the UK [40]. Seven studies reported obtaining ethics clearance [21,32,33,36,38,41,43]. On the Systematic Review Appraisal form, four studies scored 16 out of 18 (88%) [21,33,36,43], two studies scored 17 [39,41] and one study scored 18 [32]. The most common deficiencies included a lack of evidence of a systematic review of the literature being undertaken (13 studies), a lack of a detailed description of the tools used in the study sufficient to allow replication (nine studies), a lack of clear hypotheses or research questions (six studies), a lack of reporting ethics
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approval (six studies) and a lack of thorough data analysis (five studies).
Prevalence by type (i.e. Type 1 diabetes, Type 2 diabetes or gestational diabetes) was not reported separately in any of the 13 papers. As noted above, incidence was not reported.
Impact of diabetes on the health and well-being of people with intellectual and developmental disability
Of the three studies identified, all were qualitative interview studies (Table S2). One involved only the person with IDD, one involved the person and their carer, and one stated the support worker was present when necessary. The study sample sizes were 17 [19], 14 [17] and four [23], respectively. One study was conducted in the UK [17], one in the Netherlands [19] and one in New Zealand [23]. Participants were people with mild to moderate IDD, whose degree of disability was established with reference to file information and clinical judgment. Two studies included participants with both Type 1 and Type 2 diabetes [17,23], and one did not report diabetes type [18]. All three studies gained appropriate ethics approval. On the Systematic Review Appraisal form, all three studies scored 16 (88%); deficiencies were noted as a lack of systematic literature review informing the studies (three studies), a lack of detailed demographic profile of participants (two studies) and insufficient description of the interview tools (two studies). Self-management of diabetes by people with intellectual and developmental disability
Of the three studies identified, all were qualitative interview studies; one with caregivers alone, one with the person with IDD only, and one with the person with their support worker present when needed (Table S3). The sample sizes were 17 [19], 14 [23] and 13 [18], respectively. Two studies were conducted in the Netherlands [18,19], and one in New Zealand [23]. One study included participants with Type 1 and Type 2 diabetes [23], and two did not report diabetes type [18,19]. All three studies reported having obtained ethics approval. Participants were people with mild to moderate IDD, whose degree of disability was established with reference to file information and clinical judgment. One study involved support staff (social workers and nurses) as participants [18]. On the Systematic Review Appraisal form, two studies scored 16 (88%) and one scored 14 (78%). The deficiencies were a lack of a systematic literature review informing the studies (three studies), a lack of reporting of ethical approval (two studies), a lack of detailed demographic profile of participants (two studies), a lack of detailed description of the tools used (two studies), and a lack of in-depth discussion addressing the research questions (two studies).
Findings Prevalence and incidence of diabetes in people with intellectual and developmental disability
The mean prevalence of diabetes in people with IDD was 8.7%, ranging from 3.4 [42] to 18.5% [37] (Table S1).
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Impact of diabetes on the health and well-being of people with intellectual and developmental disability
Common themes among the three qualitative studies included notions of sadness and frustration regarding the diagnosis of diabetes (Table S2). Cardol et al. [19] reported that all 17 interviewees mentioned the practical consequences of diabetes for daily life including feelings of loss with regard to food, with concern about not being able to eat and drink what they liked, when they liked. This feeling of loss was more prominent in those living in community housing, as their meal options were arranged by staff and they could distinguish between what they and others were eating. Furthermore, the participants reported that diabetes negatively impacted on their choices in life, such as having dinner spontaneously, or going on holiday. Almost all participants expressed persistent worry about the future, and those in community housing reported more concerns and fearful thoughts. Similarly, Hale et al. [23] reported that participants felt that eating differently from others as well as having to perform their diabetes care needs in front of others added to the burden of diabetes. Dysch et al. [17] reported that all four of their participants felt frustrated with their diagnosis of diabetes, and the restrictions or inconveniences that accompany it; such as medication and monitoring of blood glucose levels. Despite this frustration, participants were aware of the importance of managing their diabetes; however, they also reported the activities involved to be socially stigmatizing, and they felt physically and behaviourally different from others. Self-management of diabetes by people with intellectual and developmental disability
All three studies noted that most of their participants did not have a full understanding of the optimum dietary care needed to manage their diabetes (Table S3). While two studies reported that support staff encouraged self-management [19,23], one reported the caregivers did not believe their clients to be motivated to undertake self-management [18]. Cardol et al. [19] noted that a relationship appeared to exist between a better understanding of diabetes and self-management and that self-management only occurred when the person with IDD lived alone. This was supported by the findings of another study by Cardol et al. [18] who reported that respondents with communal living arrangements found self-management more difficult because of strict daily timetables, food being prepared for them and the temptations of seeing others eat. One study reported none of the participants had received written diabetes information that they could understand [19], and another noted that participants could not recall receiving any diabetes information at diagnosis [23]. In two studies, carers reported
ª 2014 The Authors. Diabetic Medicine ª 2014 Diabetes UK
Systematic Review or Meta-analysis
their role as assisting in the medical management of the individual’s diabetes [18,23].
Discussion The present review has identified a paucity of evidence to inform policy and practice in the support of people with IDD and diabetes. We found 13 studies in which the prevalence of diabetes in people with IDD was reported and a further three qualitative studies in which impact and self-management were explored. After excluding studies with a Systematic Review Appraisal rating
Systematic Review or Meta-analysis Diabetes in people with an intellectual disability: a systematic review of prevalence, incidence and impact K. McVilly1, J. McGillivray1, A. Curtis1, J. Lehmann3, L. Morrish1 and J. Speight1,2,4 1 Deakin University, School of Psychology and Centre for Mental Health and Wellbeing Research, Burwood, Victoria, 2The Australian Centre for Behavioural Research in Diabetes, Diabetes Australia, Melbourne, Victoria, 3EdHealth Australia, Malvern, South Australia, Australia and 4AHP Research, Hornchurch, UK
Accepted 9 May 2014
Abstract Aims To establish the prevalence and incidence of Type 1 and Type 2 diabetes in people with an intellectual and developmental disability and determine their impact on health and well-being and to appraise the evidence available to inform good practice in diabetes management for people with intellectual and developmental disabilities. Methods We conducted separate searches of multiple databases (EMBASE, CINAHL, MEDLINE, PsycINFO, SCOPUS, Web of Science, PUBMED and Cochrane Library) to find relevant articles.
A total of 13 studies were identified: 13 addressed the prevalence of diabetes in people with intellectual and developmental disability, three addressed the impact of diabetes on their health and well-being and three addressed the management of diabetes. The prevalence of diabetes in people with intellectual and developmental disability remains uncertain, and the incidence of diabetes in this group of people is unknown. There is some evidence to support the assertion that people with intellectual and developmental disability might be at greater risk of diabetes than the general population. Overall, the quality of the evidence on which to base prevention and management strategies is variable.
Results
Conclusions There is a paucity of research focusing on the prevalence, incidence and impact of diabetes among people with intellectual and developmental disability. Further research is needed to inform policy and practice in this area and, in particular, work is needed to develop methodologies, evaluation tools, educational resources and diabetes care support services appropriate to the needs of people with intellectual and developmental disability.
Diabet. Med. 31, 897–904 (2014)
Introduction People with intellectual and developmental disability (IDD) comprise 1–3% of the population [1,2], with higher rates in communities characterised by poverty [3–5]. People with IDD are high-frequency users of health services, presenting with multiple comorbidities [3,6,7] and earlier manifestation compared with people without IDD, and this is confounded by a combination of genetic, personal and socio-economic factors [4,5]. People with IDD are at higher risk of Type 2 diabetes, which is attributed to obesity, reduced physical activity, elevated blood pressure and poor nutrition [8–10]. Identifying the prevalence of Type 1 diabetes in people with IDD is difficult, as they are sometimes excluded from studies for logistical reasons (e.g. communication difficulties) or their co-existing disability is not recognised or recorded; however, where co-existing IDD has been recognized, a greater prevalence has been observed in people with autism Correspondence to: Keith McVilly. E-mail: [email protected]
ª 2014 The Authors. Diabetic Medicine ª 2014 Diabetes UK
[6,14] and those with Down’s syndrome [9,10] than in the general population. The prevalence of Type 1 diabetes in people with Down’s syndrome in Denmark was identified as being four times that of all children born in Denmark in 1981–2000 [11]. In Scotland, the prevalence of Type 1 diabetes in people with Down’s syndrome is estimated at 10.6%, or 10 times greater than in the general population [12]. This higher prevalence of Type 1 diabetes among people with Down’s syndrome should be a matter of concern, given that diabetes can account for 3% of deaths annually in the general population [15]. Furthermore, diabetes-related morbidity and mortality has been identified as a particular concern for people with IDD, including those with autism [7,8]. Optimum diabetes management requires considerable self-care involving a number of practical tasks, e.g. choosing appropriate foods and portion sizes, monitoring and interpreting blood glucose levels, being physically active and taking medication [16]. People with IDD experience challenges with such tasks [1], and can be overwhelmed by them
897
DIABETICMedicine
Diabetes and people with intellectual disability K. McVilly et al.
[17]. Consequently, they rely on the support of others [1]. An emerging literature suggests that for many people with IDD, optimum diabetes care is not achieved [8,18–20]. Given the detrimental impact of persistently elevated blood glucose levels, including the development of complications, increased hospitalizations and length of hospital stay, reduced quality of life, and increased health expenditure [21], appropriate management and education in self- or supported care in people with IDD is crucial [22]. The apparent shortcomings in diabetes-related care might reflect: broader unmet healthcare needs among people with IDD [24–26]; complications associated with detecting pain [27]; diagnostic overshadowing [28]; comparatively low rates of participation in health screening and health promotion [26,29]; and insufficient training of health professionals in how to relate to, communicate with and adapt health service provision for people with IDD [18,25]. Overall, however, it is evident that diabetes management in people with IDD should be a matter of concern for policy makers, healthcare professionals and educators. Our aim therefore was to conduct a systematic review of the evidence base underpinning good practice in diabetes detection and management for people with IDD. Our questions were: (1) What is known about the prevalence and incidence of Type 1 diabetes and Type 2 diabetes in people with IDD?; (2) What is known about the impact of diabetes on the physical health and psychological wellbeing of people with IDD?; and (3) How is diabetes managed in people with IDD, and what is known about the quality of care and the degree to which people are supported to self-manage their condition?
diabetes with the addition of impact* or ‘well being’ or ‘well-being’ or ‘wellbeing’ or ‘quality of life’. Research Question 3: the terms concerning IDD and diabetes again remained the same, with the addition of: ‘self manag*’ or ‘self-manag*’ or manag*. The reference lists of relevant articles were also reviewed to identify further relevant articles. Titles and abstracts were reviewed manually to determine if they met the following inclusion criteria: (1) the paper was specific to both IDD and diabetes, and addressed at least one of the research questions; (2) participants were adults; (3) the paper had been peer-reviewed; and (4) the paper was not a duplicate of a previous paper. The exclusion criteria required the removal of articles that did not incorporate both intellectual disability (and its equivalents) and diabetes. Experimental research (e.g. investigating glucose manipulation and glucose tolerance) was deemed to be outside the scope of the present review, which had a clinical focus. There were no relevant articles in any language other than English. Articles were summarized and their quality appraised using the Systematic Review Appraisal form [30]. The appraisal tool was informed by quality criteria recommended by the Social Care Institute for Excellence [31], the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) [49], and the Effective Public Health Practice Project, as described by Thomas et al. [33]. The tool used nine quality domains: reference to the literature; having a research focus; having ethics approval; providing details of the method and procedures; describing the participants; describing the tools used; details of the data analysis; details of the findings; discussion of results and implications of the findings; and supporting references. Ratings were conducted according to a three-point scale (0, 1 or 2), with a total possible score of 18. Ratings were made on the basis of group consensus.
Methods We conducted separate searches of multiple databases (EMBASE, CINAHL, MEDLINE, PsycINFO, SCOPUS, Web of Science, PUBMED and Cochrane Library) for each of the questions listed below (the most recent on 29th April 2013). The key search terms for each research question are as follows. Research Question 1: ‘intellectual* disabil*’ or ‘mental retardation’ or ‘intellectual* impair*’ or ‘learning disabil*’ or ‘developmental disabil*’ and diabet* and prevalen* and/or inciden*. Diabetes mellitus was considered the focus of the current review. Consequently, conditions identified as pre-diabetic states, or as difficulties with glucose metabolism more generally, although not necessarily excluded from the search, were not the focus of specific searches in their own right. Syndrome-specific searches were not conducted, as the diversity of options was considered too great and there was no established evidence base to focus any such search. It is reasonable, however, to conclude that syndrome-specific research in this population would typically make reference to the broader term IDD and the related terms included in the current search strategy. Research Question 2: the same terms were used in regard to IDD and
898
Results Prevalence and incidence of diabetes in people with intellectual and developmental disability
The initial search discovered 1233 abstracts, which were screened against the inclusion criteria. After removing duplicates and articles not meeting the review criteria, 72 articles remained. Each was read in depth to determine its suitability for inclusion, specifically based on whether it reported prevalence or incidence rates for diabetes in people with IDD. A total of 13 studies were identified (Fig. 1).
Impact of diabetes on health and well-being among people with an intellectual and developmental disability
The initial search discovered 560 articles, which were further reviewed against the inclusion criteria, as described above. After removing duplicates and articles not meeting the review
ª 2014 The Authors. Diabetic Medicine ª 2014 Diabetes UK
Systematic Review or Meta-analysis
Queson 1 - Prevalence: 1233 abstracts returned by search
DIABETICMedicine
Queson 2 - Impact: 560 abstracts returned by search
1161 abstracts excluded. Reasons: -Duplicate - Irrelevant
72 full-text arcles reviewed
4278 abstracts excluded.
Reasons:
Reasons:
-Duplicate
-Duplicate
- Irrelevant
- Irrelevant
16 arcles excluded.
Reasons:
-Did not include both IDD & diabetes
- Did not report prevalence or incidence stascs
11 full-text arcles reviewed
8 arcles excluded. Reasons:
Reasons:
-Did not include both IDD & diabetes
13 studies included in review
541 abstracts excluded.
19 full-text arcles reviewed
58 arcles excluded.
Queson 3 - Management: 4289 abstracts returned by search
- Did not report on the impact of diabetes on people with IDD
3 studies included in review
-Did not include both IDD & diabetes - Did not report on the selfmanagement of diabetes in people with IDD
3 studies included in review
FIGURE 1 Flow chart of search strategy and results for research questions on the prevalence, impact and management of diabetes in people with intellectual and developmental disability.
criteria, 19 articles were identified. Each was read in depth to determine its suitability for inclusion, based on whether it reported the impact (on physical or psychological health, and well-being) of diabetes on people with IDD. Three studies were identified (Fig. 1).
Management of diabetes by people with intellectual and developmental disability
The initial search discovered 4289 articles. After removing duplicates and articles not meeting the review criteria, 11 articles remained. Each was read in depth to determine its suitability for inclusion, based on whether it reported on the self-management of diabetes in people with IDD. Three studies were identified (Fig. 1). The articles identified as addressing each of the three research questions are summarized in the supplementary online tables (Tables S1–3). The tables are organized according to country of origin, aims and research questions, category of paper, ethics approval, overall design/methodology, participants, type of diabetes, measures/analysis, findings and the quality rating for each article based on the Systematic Review Appraisal Form [30].
Study characteristics and quality appraisal Prevalence and incidence of diabetes in people with intellectual and developmental disability
None of the studies reported the incidence of diabetes in people with IDD. Prevalence was reported in 13 studies
ª 2014 The Authors. Diabetic Medicine ª 2014 Diabetes UK
(Table S1). Generally, the statistical data reported were limited (i.e. there was an absence of confidence intervals and effect sizes). In addition, none of the studies distinguished between Type 1 diabetes and Type 2 diabetes in the reporting of prevalence and none made reference to gestational diabetes. Assessment of prevalence in the included studies was made using a range of methods, including data extraction from medical records [32–36], survey [26,37–40], interview [41], and physical examination [21,42,43]. The largest study comprised 27 116 participants [37], while the smallest comprised four participants [17]. All studies included people with mild and moderate IDD, with three including those with severe and profound IDD. Co-existing conditions included cerebral palsy and Down’s syndrome. The average age of participants was 46 years (excluding three studies in which age was not reported); the youngest mean age was 35.4 years [21] and oldest 61.5 years [32]. Six studies were conducted in the USA [21,33–37,43], three in the Netherlands [32,41,44], and one each in Hong Kong [38], China [42], Europe [39] and the UK [40]. Seven studies reported obtaining ethics clearance [21,32,33,36,38,41,43]. On the Systematic Review Appraisal form, four studies scored 16 out of 18 (88%) [21,33,36,43], two studies scored 17 [39,41] and one study scored 18 [32]. The most common deficiencies included a lack of evidence of a systematic review of the literature being undertaken (13 studies), a lack of a detailed description of the tools used in the study sufficient to allow replication (nine studies), a lack of clear hypotheses or research questions (six studies), a lack of reporting ethics
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approval (six studies) and a lack of thorough data analysis (five studies).
Prevalence by type (i.e. Type 1 diabetes, Type 2 diabetes or gestational diabetes) was not reported separately in any of the 13 papers. As noted above, incidence was not reported.
Impact of diabetes on the health and well-being of people with intellectual and developmental disability
Of the three studies identified, all were qualitative interview studies (Table S2). One involved only the person with IDD, one involved the person and their carer, and one stated the support worker was present when necessary. The study sample sizes were 17 [19], 14 [17] and four [23], respectively. One study was conducted in the UK [17], one in the Netherlands [19] and one in New Zealand [23]. Participants were people with mild to moderate IDD, whose degree of disability was established with reference to file information and clinical judgment. Two studies included participants with both Type 1 and Type 2 diabetes [17,23], and one did not report diabetes type [18]. All three studies gained appropriate ethics approval. On the Systematic Review Appraisal form, all three studies scored 16 (88%); deficiencies were noted as a lack of systematic literature review informing the studies (three studies), a lack of detailed demographic profile of participants (two studies) and insufficient description of the interview tools (two studies). Self-management of diabetes by people with intellectual and developmental disability
Of the three studies identified, all were qualitative interview studies; one with caregivers alone, one with the person with IDD only, and one with the person with their support worker present when needed (Table S3). The sample sizes were 17 [19], 14 [23] and 13 [18], respectively. Two studies were conducted in the Netherlands [18,19], and one in New Zealand [23]. One study included participants with Type 1 and Type 2 diabetes [23], and two did not report diabetes type [18,19]. All three studies reported having obtained ethics approval. Participants were people with mild to moderate IDD, whose degree of disability was established with reference to file information and clinical judgment. One study involved support staff (social workers and nurses) as participants [18]. On the Systematic Review Appraisal form, two studies scored 16 (88%) and one scored 14 (78%). The deficiencies were a lack of a systematic literature review informing the studies (three studies), a lack of reporting of ethical approval (two studies), a lack of detailed demographic profile of participants (two studies), a lack of detailed description of the tools used (two studies), and a lack of in-depth discussion addressing the research questions (two studies).
Findings Prevalence and incidence of diabetes in people with intellectual and developmental disability
The mean prevalence of diabetes in people with IDD was 8.7%, ranging from 3.4 [42] to 18.5% [37] (Table S1).
900
Impact of diabetes on the health and well-being of people with intellectual and developmental disability
Common themes among the three qualitative studies included notions of sadness and frustration regarding the diagnosis of diabetes (Table S2). Cardol et al. [19] reported that all 17 interviewees mentioned the practical consequences of diabetes for daily life including feelings of loss with regard to food, with concern about not being able to eat and drink what they liked, when they liked. This feeling of loss was more prominent in those living in community housing, as their meal options were arranged by staff and they could distinguish between what they and others were eating. Furthermore, the participants reported that diabetes negatively impacted on their choices in life, such as having dinner spontaneously, or going on holiday. Almost all participants expressed persistent worry about the future, and those in community housing reported more concerns and fearful thoughts. Similarly, Hale et al. [23] reported that participants felt that eating differently from others as well as having to perform their diabetes care needs in front of others added to the burden of diabetes. Dysch et al. [17] reported that all four of their participants felt frustrated with their diagnosis of diabetes, and the restrictions or inconveniences that accompany it; such as medication and monitoring of blood glucose levels. Despite this frustration, participants were aware of the importance of managing their diabetes; however, they also reported the activities involved to be socially stigmatizing, and they felt physically and behaviourally different from others. Self-management of diabetes by people with intellectual and developmental disability
All three studies noted that most of their participants did not have a full understanding of the optimum dietary care needed to manage their diabetes (Table S3). While two studies reported that support staff encouraged self-management [19,23], one reported the caregivers did not believe their clients to be motivated to undertake self-management [18]. Cardol et al. [19] noted that a relationship appeared to exist between a better understanding of diabetes and self-management and that self-management only occurred when the person with IDD lived alone. This was supported by the findings of another study by Cardol et al. [18] who reported that respondents with communal living arrangements found self-management more difficult because of strict daily timetables, food being prepared for them and the temptations of seeing others eat. One study reported none of the participants had received written diabetes information that they could understand [19], and another noted that participants could not recall receiving any diabetes information at diagnosis [23]. In two studies, carers reported
ª 2014 The Authors. Diabetic Medicine ª 2014 Diabetes UK
Systematic Review or Meta-analysis
their role as assisting in the medical management of the individual’s diabetes [18,23].
Discussion The present review has identified a paucity of evidence to inform policy and practice in the support of people with IDD and diabetes. We found 13 studies in which the prevalence of diabetes in people with IDD was reported and a further three qualitative studies in which impact and self-management were explored. After excluding studies with a Systematic Review Appraisal rating
