Is high-altitude environment a risk factor for childhood overweight and obesity in Saudi Arabia?

To describe the prevalence of childhood overweight and obesity in rural high- and low-altitude populations of southwestern Saudi Arabia and to identify specific at-risk groups within these populations.

A cross-sectional study was conducted on 912 school children and adolescents aged 6-15 years born and living permanently at high altitudes (2800-3150 m) and 972 children and adolescents of comparable ages born and living permanently at low altitudes (< or =500 m). Height and weight were measured. For children <10 years, the weight-to-height index according to World Health Organization (WHO) standards was used for assessing overweight and obesity. For adolescents 10-15 years, overweight and obesity were assessed by age and gender-specific percentiles for body mass index based on the WHO/National Centre for Health Statistics reference population. A questionnaire was used for measuring parents' socioeconomic status.

The overall prevalence of overweight and obesity at high and low altitudes was 10%. The study showed that some school children and adolescents were at a significantly higher risk of developing overweight and obesity. Significant risk factors included moderate-to-high parental income, age > or =10 years, high-altitude birth and residence, and female sex (crude odds ratio 3.2 [95% CI, 1.8- 5.5], 2.3 [95% CI, 1.6-3.2], 2.1 [95% CI, 1.5-2.9], and 1.9 [95% CI, 1.4-2.6], respectively). A multivariate analysis using the direct binary logistic regression model revealed that moderate-to-high parental income, age > or =10 years, female sex, and high-altitude birth and residence were significant independent predictors of childhood overweight and obesity. (adjusted OR 3.2 [95% CI, 1.6-2.6], 2.6 [95% CI, 1.8-3.8], 2.0 [95% CI, 1.6-2.9], and 1.8 [95% CI, 1.3-2.6]), respectively.

The present study identified risk factors for childhood overweight and obesity in Saudi Arabia. Among these, high altitude was a significant and independent factor. Future research is warranted to evaluate the exact mechanism by which a high-altitude environment may contribute to childhood overweight and obesity.