PEDIATRICOBESITY SHORTCOMMUNICATION
Sex differences in the association between body mass index and hypertension – a cross-sectional study in 717 812 adolescents B. Gordon1,2, A. Shamiss2,3, E. Derazne2, D. Tzur1 and A. Afek2
1 Israeli Defense Force Medical Corps, Tel Hashomer, Israel; 2The Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; 3 The Chaim Sheba Medical Center, Ramat Gan, Israel
Address for correspondence: Dr B Gordon, Department of Family Medicine and Department of Medical Management, Medical Corps, Israeli Defense Force, 38 Tarshish St. Shoham, 60850, Israel. E-mail: [email protected] Received 11 November 2014; revised 3 March 2015; accepted 11 March 2015
Summary In order to examine sex-specific differences in the association of body mass index (BMI) and hypertension, we conducted a retrospective, cross-sectional study of 717 812 (402 914 men and 314 898 women) Israeli Jewish adolescents aged 16.0–19.99 years medically screened for military service. A diagnosis of hypertension was established per history or if a mean of 10 separate blood pressure measurements exceeded 140/90, following an initial measurement higher than 140/90. Weight and height were measured. Prevalence of hypertension was 0.42% in men and 0.05% in women. In men, BMI was significantly associated with hypertension from the third decile (odds ratio [OR] 1.67, 1.06–2.65) up to the 10th decile (OR 30.17, 20.83–43.69). In women, we observed a significantly increased risk for hypertension in the ninth decile (OR 3.82, 1.42–10.22) and in the 10th decile (OR 18.92, 7.7–46.51), with no visible trend in lower deciles. BMI effects on hypertension prevalence are different in male and female adolescents. Keywords: Adolescents, body mass index, hypertension, sex.
Introduction As in adults up until middle-age, hypertension is mainly a disease of men (1–4). Hypertension is associated with body mass index (BMI) (2,5–7), but we are unaware of previous studies that evaluated the sex-specific pattern of association between the entire BMI range and hypertension in adolescents.
Methods All Israeli residents, excluding some minority population, at the age of 17 years, go through mandatory medical evaluation, which includes questionnaires filled by the candidate and his family physician, height, weight and blood pressure (BP) measurements, a medical examination by a physician and further tests and consultations as needed. In this cross-sectional research, we included all Jewish teenagers, aged 16.0–19.99 years examined in the years 1998–2009. Excluded were those with no recorded weight or height measurements. Height and weight were measured with shoes off and with undergarments, or only light clothes on, by a trained medical technician. BMI was calculated as weight in kilograms divided by the squared height in meters. BP was measured in the morning at room temperature (20–25°C) by a trained medical technician, in the seated position, using a mercury sphygmomanometer at the right upper arm. For 30 min prior to measurement, subjects were asked to refrain from smoking, eating or
© 2015 World Obesity. Pediatric Obesity ••, ••–••
exercise. If systolic or diastolic measurements were ≥140 or ≥90 mm Hg, respectively, then the mean of 10 separate BP measurements, performed over a period of several weeks was obtained before a formal diagnosis of hypertension was made. Information on a diagnosis of hypertension was available through a questionnaire filled by the participant’s family physician. Data on sex, BMI, diagnosis of hypertension and other personal data were stored in a central database and were retrieved with the approval of the medical corps institutional review board, while maintaining strict subject’s anonymity. We divided the participants into 10 groups according to BMI deciles, separately for boys and girls. Statistical significance of the prevalence of hypertension across the deciles was tested with χ2 test. Odds ratios (OR) and 95% confidence intervals for the occurrence of hypertension were estimated with logistic regression models separately for men and women in which the lowest decile was the reference. Statistical significance was considered when the P-value was lower than 0.05. All statistical analysis was performed using the Statistical Package for the Social Sciences (SPSS) version 17 (SPSS, Inc., Chicago, IL, USA).
Results The study population included 717 812 participants, 402 914 men and 314 898 women. The age distribution
SHORTCOMMUNICATION
doi:10.1111/ijpo.12029
© 2015 World Obesity. Pediatric Obesity ••, ••–••
17.2
Mean BMI
17.12
Mean BMI
1
OR (95% CI)
0.38 (0.07–1.97)
2 (0.01)
3.88
50.9
6.3
162.23
0.22
19.27
19.63
18.9
32692
1.67 (1.06–2.65)
1.42 (0.45–4.48)
7 (0.02)
4.08
52.45
6.12
161.87
0.2
19.99
20.31
19.63
30832
2.04 (1.31–3.19)
59 (0.15)
4.82
61.28
6.81
174.04
0.2
20.2
20.55
19.84
40096
4
BMI, body mass index; CI, confidence interval; OR, odds ratio; SD, standard deviation.
0.82 (0.22–3.07)
3.76 4 (0.01)
3.93
5 (0.02)
SD
6.29 48.85
6.37
45.52
162.56
162.94
0.26
18.46
18.88
17.99
30407
0.99 (0.59–1.65)
Number diagnosed with hypertension percentage (%)
Mean weight
SD
Mean height
0.72
17.98
Maximum BMI
SD
12.04
31303
1
4.71 49 (0.12)
4.45
29 (0.07)
4.79
29 (0.07)
6.89 58.93
6.71
173.83
0.22
19.47
19.84
19.05
40680
3
54.49
6.98
52.12
174.05
0.28
18.62
19.05
18.11
40767
2
173.92
Minimum BMI
N
Women
OR (95% CI)
Number diagnosed with hypertension percentage (%)
SD
Mean weight
SD
Mean height
0.76
18.11
BMI max
SD
12.04
40211
1
BMI min
N
Men
2.30 (0.81–6.53)
12 (0.04)
4.21
54.45
6.2
162.11
0.22
20.69
21.08
20.32
32713
1.92 (1.22–3.01)
55 (0.14)
4.91
63.2
6.71
173.88
0.2
20.91
21.26
20.56
39779
5
1.26 (0.38–4.11)
6 (0.02)
4.38
56.04
6.2
161.54
0.22
21.44
21.85
21.08
29925
3.13 (2.06–4.76)
92 (0.23)
5.1
65.74
6.73
174.08
0.23
21.66
22.06
21.27
40796
6
2.53 (0.9–7.1)
13 (0.04)
4.61
58.37
6.3
161.59
0.29
22.32
22.86
21.87
32173
3.47 (2.29–5.25)
98 (0.25)
5.42
68.41
6.85
174.11
0.28
22.53
23.04
22.06
39234
7
1.56 (0.51–4.76)
8 (0.02)
4.78
61.47
6.13
161.71
0.38
23.47
24.17
22.86
32139
5.85 (3.95–8.67)
172 (0.42)
5.3
71.84
6.86
174.05
0.4
23.68
24.42
23.04
40909
8
860 (2.13)
12.15
92.29
7.06
174.28
3.1
30.33
47.96
26.86
40360
10
95 (0.30)
18.63
78.62
6.38
162
3.18
29.9
47.63
26.5
31525
3.82 (1.42–10.22) 18.92 (7.7–46.51)
19 (0.06)
5.4
65.93
6.29
161.65
0.66
25.19
26.49
24.19
31189
9.22 (6.28–13.53) 30.17 (20.83–43.69)
265 (0.66)
6.74
77.43
6.87
174.15
0.7
25.49
26.86
24.43
40082
9
171 (0.05)
20.56
57.27
6.26
162.02
3.68
21.79
47.63
12.04
314898
1708 (0.42)
32.69
66.78
6.85
174.04
3.76
22.01
47.96
12.04
402914
Total
|
BMI deciles
Table 1 Characteristics of the study population, prevalence of hypertension and odds ratios across BMI deciles in male and female teenagers
SHORTCOMMUNICATION 2 B. Gordon et al.
|
3
SHORTCOMMUNICATION
Effect of sex on BMI – hypertension association
Figure 1 Prevalence of hypertension across body mass index deciles in men and women. was as follows: 142 805 aged 16–16.99, 469 290 aged 17–17.99, 84 124 aged 18–18.99 and 21 593 aged 19–19.99. Average age at examination was 16.98 years. The minimum, maximum, average BMI and standard deviation, as well as mean and standard deviation of weight and height, for the entire population and for the 10 BMI deciles are given in Table 1; 1708 men (0.42%) and 171 women (0.05%) were diagnosed with hypertension. The prevalence of hypertension across the BMI deciles is given in Table 1. A pattern of increasing prevalence of hypertension with increasing BMI is apparent, especially in men. The odds ratio for hypertension across the BMI deciles is given in Table 1. A statistically significant increased risk for hypertension was observed in males from the third decile, with a clear dose–response curve up to the 10th decile as shown in Fig. 1. In women, such increase in risk was observed from the ninth decile without a similar phenomenon.
Discussion Our finding of a higher prevalence of hypertension in men is in concordance with the literature (1). The prevalence of hypertension in our population is much lower than described in the literature in various populations (8–13). These differences probably stem from the fact that most studies on hypertension prevalence rely on self-report of high BP or on a single measurement of BP. Our study based the diagnosis on repeated BP measurements. We
therefore believe that the prevalence of hypertension reported in our study is probably closer to the truth than those reported previously. We found that BMI at the high end of the scale, in the overweight and obese categories, is associated with increased risk of prevalent hypertension. This finding is well documented in the literature (10,14). However, we also found that hypertension was associated with increasing BMI within the ‘normal’ range in men, but not in women. To our knowledge this is the first time that this sex-specific variance in the association of the entire BMI range and prevalent hypertension is reported. The reasons for these differences are yet to be determined. Our study has several limitations. Our definition of hypertension in this age group does not conform with published guidelines, which define hypertension using age-, heightand sex-related tables of normal and elevated BP (15–17). We believe that this might affect the prevalence of hypertension, more so in women, but not the trend across the BMI range. Another limitation is the lack of details on the tanner stage of subjects in our cohort as the prevalence of hypertension rises in puberty (18). The cross-sectional design of the study limits the ability to determine causality. A low number of hypertension cases in women, especially in the low to normal BMI might impair the statistical power of the study. Our study has several strong points. First is the large-scale screening of both BMI and BP. This universal mandatory process makes selection bias unlikely.
© 2015 World Obesity. Pediatric Obesity ••, ••–••
SHORTCOMMUNICATION
4
|
B. Gordon et al.
Reporting biases are unlikely because of the fact that weight, height and BP are measured at standard conditions and not merely reported. The uniformity of the study population age-wise is another strength that allows us to isolate the effect of BMI on hypertension prevalence. In conclusion, we found that the association of BMI and prevalent hypertension behaves differently in men and women. While in women this association is apparent in the higher range of BMI, in men, it is evident in BMI well in the normal range. This finding can direct different screening programmes in adolescent boys and girls for hypertension, and target differently weight-losing initiatives in boys and girls. Further study is needed to determine the causes of this difference.
Conflict of interest statement No conflict of interest to disclose.
Author contributions BG searched the literature, designed the study, analysed and interpreted the data, and wrote the paper. AS and AA designed the study, and analysed and interpreted the data. ED and DT designed the study, and collected, analysed, and interpreted the data. All authors were involved in writing the paper and had final approval of the submitted and published versions.
References 1. Wolf-Maier K, Cooper RS, Banegas JR, et al. Hypertension prevalence and blood pressure levels in 6 European countries, Canada, and the United States. JAMA 2003; 289: 2363–2369. 2. Sorof JM, Lai D, Turner J, Poffenbarger T, Portman RJ. Overweight, ethnicity, and the prevalence of hypertension in school-aged children. Pediatrics 2004; 113: 475–482. 3. Davis CL, Flickinger B, Moore D, Bassali R, Domel Baxter S, Yin Z. Prevalence of cardiovascular risk factors in schoolchildren in a rural Georgia community. Am J Med Sci 2005; 330: 53–59. 4. Willi SM, Hirst K, Jago R, et al. Cardiovascular risk factors in multi-ethnic middle school students: the healthy primary prevention trial. Pediatr Obes. 2012; 7: 230– 239. 5. He Q, Ding ZY, Fong DY, Karlberg J. Blood pressure is associated with body mass index in both normal and obese children. Hypertension 2000; 36: 165–170.
© 2015 World Obesity. Pediatric Obesity ••, ••–••
6. Rosner B, Prineas R, Daniels SR, Loggie J. Blood pressure differences between blacks and whites in relation to body size among US children and adolescents. Am J Epidemiol 2000; 151: 1007–1019. 7. Smith LP, Gilstad-Hayden K, Carroll-Scott A, Ickovics J. High waist circumference is associated with elevated blood pressure in non-Hispanic White but not Hispanic children in a cohort of pre-adolescent children. Pediatr Obes 2014; 9: e145–e148. 8. Barakat-Haddad C. Prevalence of high blood pressure, heart disease, thalassemia, sickle-cell anemia, and irondeficiency anemia among the UAE adolescent population. J Environ Public Health 2013; 2013: 680631. 9. Rahman AJ, Qamar FN, Ashraf S, Khowaja ZA, Tariq SB, Naeem H. Prevalence of hypertension in healthy school children in Pakistan and its relationship with body mass index, proteinuria and hematuria. Saudi J Kidney Dis Transpl 2013; 24: 408–412. 10. Freedman DS, Goodman A, Contreras OA, DasMahapatra P, Srinivasan SR, Berenson GS. Secular trends in BMI and blood pressure among children and adolescents: the Bogalusa Heart Study. Pediatrics 2012; 130: e159–e166. 11. Cao ZQ, Zhu L, Zhang T, Wu L, Wang Y. Blood pressure and obesity among adolescents: a school-based population study in China. Am J Hypertens 2012; 25: 576–582. 12. Falkner B, Lurbe E, Schaefer F. High blood pressure in children: clinical and health policy implications. J Clin Hypertens (Greenwich) 2010; 12: 261–276. 13. Obarzanek E, Wu CO, Cutler JA, Kavey RE, Pearson GD, Daniels SR. Prevalence and incidence of hypertension in adolescent girls. J Pediatr 2010; 157: 461–467. 14. Dasgupta K, O’Loughlin J, Chen S, et al. Emergence of sex differences in prevalence of high systolic blood pressure: analysis of a longitudinal adolescent cohort. Circulation 2006; 114: 2663–2670. 15. Lurbe E, Cifkova R, Cruickshank JK, et al. Management of high blood pressure in children and adolescents: recommendations of the European Society of Hypertension. J Hypertens 2009; 27: 1719–1742. 16. National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents. The fourth report on the diagnosis, evaluation, and treatment of high blood pressure in children and adolescents. Pediatrics 2004; 114: 555–576. 17. Falkner B, Gidding S. Childhood obesity and blood pressure: back to the future? Hypertension 2011; 58: 754– 755. 18. Vartiainen E, Tuomilehto J, Nissinen A. Blood pressure in puberty. Acta Paediatr Scand 1986; 75: 626–631.
Sex differences in the association between body mass index and hypertension – a cross-sectional study in 717 812 adolescents B. Gordon1,2, A. Shamiss2,3, E. Derazne2, D. Tzur1 and A. Afek2
1 Israeli Defense Force Medical Corps, Tel Hashomer, Israel; 2The Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; 3 The Chaim Sheba Medical Center, Ramat Gan, Israel
Address for correspondence: Dr B Gordon, Department of Family Medicine and Department of Medical Management, Medical Corps, Israeli Defense Force, 38 Tarshish St. Shoham, 60850, Israel. E-mail: [email protected] Received 11 November 2014; revised 3 March 2015; accepted 11 March 2015
Summary In order to examine sex-specific differences in the association of body mass index (BMI) and hypertension, we conducted a retrospective, cross-sectional study of 717 812 (402 914 men and 314 898 women) Israeli Jewish adolescents aged 16.0–19.99 years medically screened for military service. A diagnosis of hypertension was established per history or if a mean of 10 separate blood pressure measurements exceeded 140/90, following an initial measurement higher than 140/90. Weight and height were measured. Prevalence of hypertension was 0.42% in men and 0.05% in women. In men, BMI was significantly associated with hypertension from the third decile (odds ratio [OR] 1.67, 1.06–2.65) up to the 10th decile (OR 30.17, 20.83–43.69). In women, we observed a significantly increased risk for hypertension in the ninth decile (OR 3.82, 1.42–10.22) and in the 10th decile (OR 18.92, 7.7–46.51), with no visible trend in lower deciles. BMI effects on hypertension prevalence are different in male and female adolescents. Keywords: Adolescents, body mass index, hypertension, sex.
Introduction As in adults up until middle-age, hypertension is mainly a disease of men (1–4). Hypertension is associated with body mass index (BMI) (2,5–7), but we are unaware of previous studies that evaluated the sex-specific pattern of association between the entire BMI range and hypertension in adolescents.
Methods All Israeli residents, excluding some minority population, at the age of 17 years, go through mandatory medical evaluation, which includes questionnaires filled by the candidate and his family physician, height, weight and blood pressure (BP) measurements, a medical examination by a physician and further tests and consultations as needed. In this cross-sectional research, we included all Jewish teenagers, aged 16.0–19.99 years examined in the years 1998–2009. Excluded were those with no recorded weight or height measurements. Height and weight were measured with shoes off and with undergarments, or only light clothes on, by a trained medical technician. BMI was calculated as weight in kilograms divided by the squared height in meters. BP was measured in the morning at room temperature (20–25°C) by a trained medical technician, in the seated position, using a mercury sphygmomanometer at the right upper arm. For 30 min prior to measurement, subjects were asked to refrain from smoking, eating or
© 2015 World Obesity. Pediatric Obesity ••, ••–••
exercise. If systolic or diastolic measurements were ≥140 or ≥90 mm Hg, respectively, then the mean of 10 separate BP measurements, performed over a period of several weeks was obtained before a formal diagnosis of hypertension was made. Information on a diagnosis of hypertension was available through a questionnaire filled by the participant’s family physician. Data on sex, BMI, diagnosis of hypertension and other personal data were stored in a central database and were retrieved with the approval of the medical corps institutional review board, while maintaining strict subject’s anonymity. We divided the participants into 10 groups according to BMI deciles, separately for boys and girls. Statistical significance of the prevalence of hypertension across the deciles was tested with χ2 test. Odds ratios (OR) and 95% confidence intervals for the occurrence of hypertension were estimated with logistic regression models separately for men and women in which the lowest decile was the reference. Statistical significance was considered when the P-value was lower than 0.05. All statistical analysis was performed using the Statistical Package for the Social Sciences (SPSS) version 17 (SPSS, Inc., Chicago, IL, USA).
Results The study population included 717 812 participants, 402 914 men and 314 898 women. The age distribution
SHORTCOMMUNICATION
doi:10.1111/ijpo.12029
© 2015 World Obesity. Pediatric Obesity ••, ••–••
17.2
Mean BMI
17.12
Mean BMI
1
OR (95% CI)
0.38 (0.07–1.97)
2 (0.01)
3.88
50.9
6.3
162.23
0.22
19.27
19.63
18.9
32692
1.67 (1.06–2.65)
1.42 (0.45–4.48)
7 (0.02)
4.08
52.45
6.12
161.87
0.2
19.99
20.31
19.63
30832
2.04 (1.31–3.19)
59 (0.15)
4.82
61.28
6.81
174.04
0.2
20.2
20.55
19.84
40096
4
BMI, body mass index; CI, confidence interval; OR, odds ratio; SD, standard deviation.
0.82 (0.22–3.07)
3.76 4 (0.01)
3.93
5 (0.02)
SD
6.29 48.85
6.37
45.52
162.56
162.94
0.26
18.46
18.88
17.99
30407
0.99 (0.59–1.65)
Number diagnosed with hypertension percentage (%)
Mean weight
SD
Mean height
0.72
17.98
Maximum BMI
SD
12.04
31303
1
4.71 49 (0.12)
4.45
29 (0.07)
4.79
29 (0.07)
6.89 58.93
6.71
173.83
0.22
19.47
19.84
19.05
40680
3
54.49
6.98
52.12
174.05
0.28
18.62
19.05
18.11
40767
2
173.92
Minimum BMI
N
Women
OR (95% CI)
Number diagnosed with hypertension percentage (%)
SD
Mean weight
SD
Mean height
0.76
18.11
BMI max
SD
12.04
40211
1
BMI min
N
Men
2.30 (0.81–6.53)
12 (0.04)
4.21
54.45
6.2
162.11
0.22
20.69
21.08
20.32
32713
1.92 (1.22–3.01)
55 (0.14)
4.91
63.2
6.71
173.88
0.2
20.91
21.26
20.56
39779
5
1.26 (0.38–4.11)
6 (0.02)
4.38
56.04
6.2
161.54
0.22
21.44
21.85
21.08
29925
3.13 (2.06–4.76)
92 (0.23)
5.1
65.74
6.73
174.08
0.23
21.66
22.06
21.27
40796
6
2.53 (0.9–7.1)
13 (0.04)
4.61
58.37
6.3
161.59
0.29
22.32
22.86
21.87
32173
3.47 (2.29–5.25)
98 (0.25)
5.42
68.41
6.85
174.11
0.28
22.53
23.04
22.06
39234
7
1.56 (0.51–4.76)
8 (0.02)
4.78
61.47
6.13
161.71
0.38
23.47
24.17
22.86
32139
5.85 (3.95–8.67)
172 (0.42)
5.3
71.84
6.86
174.05
0.4
23.68
24.42
23.04
40909
8
860 (2.13)
12.15
92.29
7.06
174.28
3.1
30.33
47.96
26.86
40360
10
95 (0.30)
18.63
78.62
6.38
162
3.18
29.9
47.63
26.5
31525
3.82 (1.42–10.22) 18.92 (7.7–46.51)
19 (0.06)
5.4
65.93
6.29
161.65
0.66
25.19
26.49
24.19
31189
9.22 (6.28–13.53) 30.17 (20.83–43.69)
265 (0.66)
6.74
77.43
6.87
174.15
0.7
25.49
26.86
24.43
40082
9
171 (0.05)
20.56
57.27
6.26
162.02
3.68
21.79
47.63
12.04
314898
1708 (0.42)
32.69
66.78
6.85
174.04
3.76
22.01
47.96
12.04
402914
Total
|
BMI deciles
Table 1 Characteristics of the study population, prevalence of hypertension and odds ratios across BMI deciles in male and female teenagers
SHORTCOMMUNICATION 2 B. Gordon et al.
|
3
SHORTCOMMUNICATION
Effect of sex on BMI – hypertension association
Figure 1 Prevalence of hypertension across body mass index deciles in men and women. was as follows: 142 805 aged 16–16.99, 469 290 aged 17–17.99, 84 124 aged 18–18.99 and 21 593 aged 19–19.99. Average age at examination was 16.98 years. The minimum, maximum, average BMI and standard deviation, as well as mean and standard deviation of weight and height, for the entire population and for the 10 BMI deciles are given in Table 1; 1708 men (0.42%) and 171 women (0.05%) were diagnosed with hypertension. The prevalence of hypertension across the BMI deciles is given in Table 1. A pattern of increasing prevalence of hypertension with increasing BMI is apparent, especially in men. The odds ratio for hypertension across the BMI deciles is given in Table 1. A statistically significant increased risk for hypertension was observed in males from the third decile, with a clear dose–response curve up to the 10th decile as shown in Fig. 1. In women, such increase in risk was observed from the ninth decile without a similar phenomenon.
Discussion Our finding of a higher prevalence of hypertension in men is in concordance with the literature (1). The prevalence of hypertension in our population is much lower than described in the literature in various populations (8–13). These differences probably stem from the fact that most studies on hypertension prevalence rely on self-report of high BP or on a single measurement of BP. Our study based the diagnosis on repeated BP measurements. We
therefore believe that the prevalence of hypertension reported in our study is probably closer to the truth than those reported previously. We found that BMI at the high end of the scale, in the overweight and obese categories, is associated with increased risk of prevalent hypertension. This finding is well documented in the literature (10,14). However, we also found that hypertension was associated with increasing BMI within the ‘normal’ range in men, but not in women. To our knowledge this is the first time that this sex-specific variance in the association of the entire BMI range and prevalent hypertension is reported. The reasons for these differences are yet to be determined. Our study has several limitations. Our definition of hypertension in this age group does not conform with published guidelines, which define hypertension using age-, heightand sex-related tables of normal and elevated BP (15–17). We believe that this might affect the prevalence of hypertension, more so in women, but not the trend across the BMI range. Another limitation is the lack of details on the tanner stage of subjects in our cohort as the prevalence of hypertension rises in puberty (18). The cross-sectional design of the study limits the ability to determine causality. A low number of hypertension cases in women, especially in the low to normal BMI might impair the statistical power of the study. Our study has several strong points. First is the large-scale screening of both BMI and BP. This universal mandatory process makes selection bias unlikely.
© 2015 World Obesity. Pediatric Obesity ••, ••–••
SHORTCOMMUNICATION
4
|
B. Gordon et al.
Reporting biases are unlikely because of the fact that weight, height and BP are measured at standard conditions and not merely reported. The uniformity of the study population age-wise is another strength that allows us to isolate the effect of BMI on hypertension prevalence. In conclusion, we found that the association of BMI and prevalent hypertension behaves differently in men and women. While in women this association is apparent in the higher range of BMI, in men, it is evident in BMI well in the normal range. This finding can direct different screening programmes in adolescent boys and girls for hypertension, and target differently weight-losing initiatives in boys and girls. Further study is needed to determine the causes of this difference.
Conflict of interest statement No conflict of interest to disclose.
Author contributions BG searched the literature, designed the study, analysed and interpreted the data, and wrote the paper. AS and AA designed the study, and analysed and interpreted the data. ED and DT designed the study, and collected, analysed, and interpreted the data. All authors were involved in writing the paper and had final approval of the submitted and published versions.
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