Socio-demographic determinants of obesity indexes in Iran:findings from a nationwide STEPS survey

Background: Overweight and obesity are considered as non-communicable diseases (NCDs) risk factors with increasing prevalence worldwide. This nationwide study aimed to determine the socio-demographic determinants of obesity indexes in Iran. Methods: This cross-sectional study was conducted based on data from the sixth round of nationwide STEPwise approach to surveillance (STEPS) survey in the 31 provinces of Iran in 2011. A total of 9878 people aged ≥20 years were selected using a multi-stage cluster sampling method. Data were collected through three steps questionnaire including ecological, physical and biochemical measurements. We assessed body mass index (BMI), waist circumference (WC) and waist-hip ratio (WHR) as the main indicators of obesity. Results: In this study, the weighted prevalence of overweight and obesity were 34.5% (95% CI: 33.6, 35.5) and 21.5% (95% CI: 20.7, 22.3), respectively. The mean ± standard deviation (SD) of BMI among men and women were 25.4±4.4 and 26.9±5.2 kg/m2 respectively. Older age, living alone, having lower education level, being housewife or retired were associated with overweight and obesity (P 0.05). Urbanization was positively associated with BMI and WC. Being obese or overweight was associated with having a history of type 2 diabetes mellitus (T2DM), hypertension (HTN) and cardiovascular diseases (CVDs). Conclusion: The prevalence of overweight in this study was less than global rate while it was vice versa for obesity prevalence. Some socio-demographic characteristics were identified as determinants of obesity which should be considered for planning preventive and control action plans.