Obesity is a well established risk factor for type 2 diabetes, which is associated with severe chronic complications including blindness, renal failure, neuropathy, and amputations. Obesity is also a risk factor for cardiovascular diseases, hypertension, and several types of cancer including breast cancer, colorectal cancer, endometrial cancer, and kidney cancer. Thus, abnormal weight gain is a major issue for public health. The World Health Organization has estimated that ∼500 million adult individuals have obesity. The alarming increase in the prevalence of obesity is not only restricted to the United States (US), but it is a global hazard, affecting also countries with smaller income economies such as Peru.
In 2010, the Centers for Disease Control and Prevention (CDC) reported that the lowest prevalence of adult obesity in the US was in Colorado, one of the states with the highest mean elevation counties. Even more intriguing, an inverse association between altitude and self-reported body mass index (BMI) has been reported among US adult individuals, independent of risk factors and potential confounders. Whether this adjusted inverse association extends to other nationally representative populations when measured body mass index is used remains unknown.
The aim of the present study was to determine the association between altitude and obesity in a nationally representative sample of the Peruvian adult population. We utilized freely available online data from an on-site survey conducted in a nationally representative population of Peru, a country with different geographic, socio-economic, cultural, and ethnic features than the US. We estimated the prevalence ratio of obesity and abdominal obesity by altitude bands among adult individuals, 20 years or older, adjusting for age, sex, self-reported physical activity, and socio-demographic covariates.