Prevalence and determinants of obesity among adolescents in Bahrain
Over the last 30 years Bahrain has witnessed remarkable economic growth and social development. This has resulted in tremendous changes in the dietary habits and lifestyle of the population and consequently increased levels of obesity. A cross-sectional study involving a representative sample of 506 Bahraini adolescents (249 males and 257 females), aged 12 to 17 years, was carried out to estimate the prevalence of obesity, its contributing factors and relationship to the risk of developing high blood pressure. The sample was selected, using a multi-stage random sampling technique, from intermediate and secondary schools in Bahrain. Data was collected using anthropometric measurements, blood pressure measurement and a self-administered questionnaire. A separate case control study, which included a sample of obese and non-obese adolescents, was carried out to investigate the relationship between adolescents' obesity and the family environment. Twenty one percent of the male and 35% of the female participants were obese using the WHO criteria for obesity in adolescents. A distinct sexual dimorphism in the accumulation of body fat during adolescence was observed. Thirty two percent of the boys and 60% of the girls had a percentage body fat at or exceeding the high-risk threshold for fatness, according to the currently accepted criteria. Systolic blood pressure, waist circumference and waist-hip ratio were all positively associated with body fatness. Multivariate analysis showed that higher levels of mother's education, frequent snacking and distress eating were all independent factors associated with an increased risk of obesity. Factors associated with a reduced risk of obesity included playing sport outside school, walking or cycling to school and eating meals with the family. Among the family environment variables, parental obesity and history of diabetes; mother's lifestyle variables, namely physical exercise and hours of television viewing, were all found to be independently related to risk of obesity in the Bahraini teenagers. Mother's degree of control over child's eating was strongly and indirectly related to risk of obesity in the adolescents. Breastfeeding, birthweight and availability and accessibility of high calorie foods in the house did not appear to be associated with adolescents' obesity. Eighteen percent of boys and 10% of girls had high blood pressure. BMI, percent body fat and waist circumference were all significantly and positively associated with a risk of having elevated blood pressure. Approximately 30% of the adolescents underestimated their current weight and about 40% thought that their parents/peers would consider them to be leaner than they actually were. More than half of the girls and about one third of the boys expressed discontent with their current body weight. Lifestyle changes and nutrition transition associated with economic development in Bahrain has increased risk of obesity among adolescents, a characteristic now evident in most countries in the Arab Gulf Region. This study provides an insight into the various determinants of this epidemic and will help to initiate public health strategies to deal with this increasing burden on health in the region.