Overall and central obesity incidence in an urban Portuguese population

Abstract

Objective: To provide overall and central obesity incidence estimates by gender, age and educational level in an urban Portuguese population.

Methods: As part of the EPIPorto study, 1,621 Porto, Portugal adult residents were evaluated in 1999-2003 and 2005-2008. Overall obesity was defined by a BMI > or = 30.0 kg/m(2) and central obesity by a WC >88.0 cm in women and >102.0 cm in men. Relative risks (RR) and 95% confidence intervals (95% CI) were computed using Poisson regression. Survival analysis was also performed.

Results: The age-adjusted incidence rates/100 person-years of overall and central obesity were, respectively, 1.70, 95% CI: 1.34-2.19 and 5.97, 95% CI: 5.09-7.03 in women; 1.08, 95% CI: 0.73-1.64 and 2.38, 95% CI: 1.81-3.20 in men. In multivariate analysis, older women presented a higher risk of overall obesity. Moreover, a significant inverse association was found between obesity and education in women (>11 vs. <5 years: RR=0.43, 95% CI: 0.22-0.84, for overall obesity; RR=0.45 95% CI: 0.29-0.69, for central obesity). For overall obesity, 10.1% of women and 5.1% of men became obese during the 5-year study period. Higher proportions were observed regarding central obesity, 29.1% and 11.4% for women and men, respectively.

Conclusions: Over time, individuals developed central obesity faster than overall obesity. Our results support that increasing levels of education limit this ongoing development of obesity, particularly among women.