Relationship between short stature and obesity in a Brazilian survey

Introduction: The greatest geographical disparities in prevalence of obesity as well as in the prevalence of stunting among regions allowed testing whether environmental determinants of undernutrition could explain an association between short stature and increased body mass index.

Objectives: To ascertain the association between body mass index (BMI) and obesity with short stature adjusting for individual and city-level measures of socioeconomic status, using a multilevel approach.

Methods: A cross-sectional telephone survey was conducted in 2006. The study probabilistic sample consisted of 54,369 adults living in households with telephones in each urban areas of all 27 state capital cities in Brazil. The questionnaire investigated demographic and socioeconomic characteristics, recalled weight and height, and other topics.

Results: After controlling for individual and citywide socio-demographic characteristics and behaviors, high BMI was strongly associated with short stature of individuals (p=0.001). Prevalence of short stature (5th percentile) varied from 1% to 9% among cities. Among short stature women the adjusted odds of being obese was 3.0 (95% CI 2.2-4.2) compared to those with stature greater than the 5th percentile. Among men this adjusted odds ratio was 2.0 (95% CI 1.5-2.6).

Conclusions: Despite the growing body of evidence that environmental factors such as poor food choices and physical inactivity are the main determinants of the worldwide obesity epidemic, the greater difference in BMI and prevalence of obesity in the Brazilian capitals was explained mainly by individual factors. We found a strong association between obesity and short stature after adjustment for diet, physical activity, and many environmental factors. Intra and inter-generational consequences of undernutrition are an alternative explanation for the regional disparities in obesity in Brazil.