International Variation in the Relationship Between Sweetened Beverage Use and Body Mass Index in Adults with Intellectual and Developmental Disabilities

Background/ Purpose: The growing prevalence of obesity is a major global health concern. The World Health Organization (2013) estimates that at least 2.8 million deaths per year result from obesity and that global obesity has almost doubled since 1980. Recent studies indicate that individuals with intellectual and developmental disabilities (IDD) experience many health disparities, including a higher prevalence of obesity. Because obesity is a leading cause of preventable death, and people with IDD are already at increased risk of health problems, there is a need to understand modifiable risk factors associated with obesity in this population. This study aims to fill a critical knowledge gap by examining the relationship between sweetened beverage use (soda, fruit juice, and sports drinks), a modifiable risk factor for obesity, and BMI among a large sample of people with IDD. 

Methods: The Special Olympics International (SOI) Health Promotion database provided data on 40,416 athletes with IDD who participated in free health screenings in seven world regions (Africa [n=1,931], Asia-Pacific [n=1,276], East Asia [n=4,427], Europe [n=10,342], Latin America [n=7,360], Middle East [n=1,028], and North America [n=17,039]) between 2007 and 2013. Participants were aged 16-97 (M=26.95), and 51% were male. Variability in mean BMI, weekly or greater sweetened beverage use, and age were examined by world region. A random-coefficient model of BMI was estimated with group mean centered weekly sweetened beverage use as the predictor, controlling for group mean centered age, using hierarchical linear modeling. 

Results: The random-coefficient model indicated a significant positive relationship between age and BMI (γ₁₀=.135, p<.001), but not between weekly or greater sweetened beverage use and BMI (γ₂₀=-.205, p=.242), suggesting that a ten-year increase in age increased BMI by 1.35 points but that sweetened beverage use did not increase BMI. There was, however, significant between-group variation in mean BMI after controlling for age and sweetened beverage use (χ²(6)=11265.568, p<.001), in the relationship between age and BMI (χ²(6)=174.526, p<.001), and in the relationship between sweetened beverage use and BMI (χ²(6)=19.354, p=.004). Correlation coefficient values indicated that the strongest positive correlation between BMI and sweetened beverage use was in Europe (r=.086). Africa was the only country in which sweetened beverage use was associated with a lower BMI (r=.-040). 

Conclusions/Implications: Results indicate that weekly or greater sweetened beverage consumption alone does not lead to obesity in this population. Future research in this area might benefit from a more defined consumption rate. People with IDD are experiencing greater opportunities for inclusion and they are making more decisions about their health and nutrition. Thus, modifiable risk factors, including sweetened beverage consumption, and cultural factors merit further consideration in improving the health of people with IDD.  Social workers have important opportunities to research and develop health promotion efforts tailored not only for individuals of differing cognitive abilities but also for differing cultural groups.