Risk factors associated with overweight and obesity among urban school children and adolescents in Bangladesh: a case-control study

Background: Childhood obesity has become an emerging urban health problem in urban cities in Bangladesh, particularly in affluent families. Risk factors for obesity in this context have not been explored yet. The objective of this study was to identify the risk factors associated with overweight and obesity among school children and adolescents in Dhaka, Bangladesh. Methods: From October through November 2007, we conducted a case-control study among children aged 10-15 years in seven schools in Dhaka. We assessed body mass index (weight in kg/height in sq. meter) to identify the cases (overweight/obese) and controls (healthy/normal weight) following the Centers for Disease Control and Prevention age and sex specific growth chart. We used a structured questionnaire to collect demographic information and respondent's exposure to several risk factors such as daily physical activity at home and in school, hours spent on computer games and television watching, maternal education level and parents' weight and height. Results: We enrolled 198 children: 99 cases, 99 controls. Multiple logistic regression analysis revealed that having at least one overweight parent (OR = 2.8, p = 0.001) and engaging in sedentary activities for >4 hours a day (OR = 2.0, p = 0.02) were independent risk factors for childhood overweight and/or obesity while exercising = 30 minutes a day at home was a protective factor (OR = 0.4, p = 0.02). There were no significant associations between childhood overweight and sex, maternal education or physical activity at school. Conclusion: Having overweight parents along with limited exercise and high levels of sedentary activities lead to obesity among school children in urban cities in Bangladesh. Public health programs are needed to increase awareness on risk factors for overweight and obesity among children and adolescents in order to reduce the future burden of obesity-associated chronic diseases.