The prevalence of obesity and obesity-related health conditions in a large, multiethnic cohort of young adults in California.

PURPOSE

To identify population groups that are most susceptible to obesity-related health conditions at young age.

METHODS

For this population-based cross-sectional study, measured weight and height, diagnosis, laboratory, and drug prescription information were extracted from electronic medical records of 1,819,205 patients aged 20 to 39 years enrolled in two integrated health plans in California in 2007 through 2009.

RESULTS

Overall, 29.9% of young adults were obese. Extreme obesity (body mass index [BMI] ≥ 40 kg/m(2)) was observed in 6.1% of women and 4.5% of men. The adjusted relative risk (RR) for diabetes, hypertension, dyslipidemia, and the metabolic syndrome increased sharply for those individuals with a BMI of 40 or greater, with the sharpest increase in the adjusted RR for hypertension and the metabolic syndrome. The association between weight class and dyslipidemia, hypertension, and the metabolic syndrome but not diabetes was stronger among 20.0- to 29.9-year-olds compared with 30.0- to 39.9-year-olds (P for interaction < .05). For example, compared with their normal weight counterparts of the same age group, young adults with a BMI of 40.0 to 49.9, 50.0 to 59.9, and 60 or greater kg/m(2) had a RR for hypertension of 11.73, 19.88, and 30.47 (95% confidence interval [CI], 26.39-35.17) at 20 to 29 years old, and 9.31, 12.41, and 15.43 (95% CI, 14.32-16.63) at 30 to 39 years old.

CONCLUSIONS

Although older individuals were more likely to be extremely obese, the association between obesity-related health conditions was stronger in younger individuals. Hispanics and Blacks are also more likely to be obese, including extremely obese, putting them at an elevated risk for premature cardiovascular disease and some cancers relative to non-Hispanic Whites.