Incidence and potential risk factors of obesity among Tehranian adults

AimEvaluating the incidence of obesity and its risk factors among Tehranian adults.Material & methodsIn this population-based cohort, non-obese participants, aged ≥ 20 years, were followed for development of obesity (Body Mass Index (BMI) ≥ 30). Incidence density and cumulative incidence rates of obesity were calculated for each sex. Cox proportional hazard regression was used to determine the association of potential obesity risk factors including: age, BMI, metabolic syndrome, waist circumference (WC), smoking, marital status, education, and physical activity.ResultA total of 7257 participants (3536 men) were followed for a median of 8 years. At baseline, mean age, BMI and WC were 41.3 ± 14.6 years, 25.1 ± 2.9 kg/m² (24.9 ± 3 kg/m² men and 25.2 ± 3 kg/m² women), and 84.8 ± 9.8 cm (87.06 ± 9.2 cm men and 82.6 ± 9.9 cm women) respectively. During the follow-up, 1345 participants (876 women) developed obesity contributing to cumulative incidences of 31.3% (CI: 29.9%–32.7%), 38.1% (CI: 36.2%–40.1%), and 23.4% (CI: 21.6%–25.3%) for the whole population, women, and men, respectively. Corresponding incidence density rates per 1000 person-year were 25.9 (CI: 24.5–27.3), 33.67 (CI: 31.5–36.0), and 18.0 (CI: 16.5–19.7), respectively. Highest incidence rates were observed during their 40s and 20s for women and men, respectively. Participants with metabolic syndrome, lower educational level, higher BMI and WC, were at higher risk of obesity development in both sexes.ConclusionHigh incidence of obesity was observed among Tehranian adults with higher incidence of obesity in women. Different modifiable variables may act as risk factors for obesity development which should be targeted to control the epidemic of obesity.