Severe obesity and cardio-metabolic comorbidities: a nationwide study of 2.8 million adolescents

Abstract

Background: Severe obesity is rising among adolescents, but data on the prevalence of metabolic abnormalities among this group are limited. We assessed the secular trend of severe obesity and its association with major cardio-metabolic morbidities.

Methods: A total of 2,785,227 Israeli adolescents (aged 17.2 ± 0.5 years) who underwent a pre-recruitment medical examination including routine measurements of weight, height and blood pressure between 1967 and 2015 were included. In all, 230,639 adolescents with abnormally excessive BMI were classified into overweight, classes I, II, and III (severe) obesity. Logistic regression was applied to determine the association between BMI groups and prehypertension, high blood pressure and type 2 diabetes (T2DM).

Results: There was 45-fold increase in the prevalence of class III obesity during study period. Severe obesity was recorded in 2060 males and 1149 females, in whom nearly 35 and 43% had prehypertension or high blood pressure, respectively. Compared with adolescents with overweight, the odds ratios (ORs) for high blood pressure in classes II and III obesity groups, respectively, were 2.13 (95% CI, 2.04-2.23) and 2.86 (2.60-3.15) in males, and 2.59 (2.43-2.76) and 3.44 (3.04-3.90) in females, whereas the ORs for T2DM were 19.1 (12.3-29.6) and 38.0 (22.6-64.0) in males, and 15.1 (11.4-20.0) and 24.8 (17.2-35.7) in females. Results persisted in extensive sensitivity analyses including a longitudinal follow-up (median: males, 3.4 years; females, 4.9 years).

Conclusions: Severe obesity showed a marked secular increase and was associated with significantly higher risk for abnormal blood pressure and T2DM than lower degrees of obesity, in both males and females.