Background: 17% of youth in the United States are obese. Obesity has been linked to higher prevalence of hypertension. Past studies were limited by their size and conflicting results. The aim of the present study was to analyze trends in adolescents obesity between 1998 and 2011 and to evaluate the relationship between blood pressure and BMI in healthy adolescents.
Methods: All adolescents that underwent a medical exam in the years 1998-2011 and were found fit for combat duties in the Israeli Defense Force were included.
Results: The cohort included 714,922 healthy adolescents with 59% of them being males. The mean age was 17.4±0.45 and mean BMI was 22 ± 3.5 kg/m2. The percentage of overweight adolescents (BMI > 25 kg/m2) has increased from 13.2% in 1998 to 21% in 2011, p < 0.001. The mean systolic and diastolic blood pressures (SBP and DBP) increased with increasing BMI deciles (SBP by 10 mmHg and DBP by 3-4 mmHg from the 1st decile to the 10th decile, p < 0.001 for both). In multivariate analysis, each increase of one unit of BMI was associated with an increased risk of SBP above 130mmHg in both males (or=1.108 , CI 95% 1.107-1.110 , p<0.001) and females (or=1.114 , CI 95% 1.139-1.146 , p<0.001).
Conclusions: BMI in adolescents is significantly associated with SBP and DBP in both genders and in both the normal weight and overweight groups. There has been consistent trend of increasing BMI values over recent years.
