Waist-height index curves of Colombian adults

Introduction. Colombia presents a progressive increase in overweight and abdominal obesity in adults, with a higher impact on women. Objective. To design percentile curves of the waist-height index of Colombian adults by sex and age. Materials and methods. We did a secondary analysis of the data from the Encuesta Nacional de la Situación Nutricional 2015, which contained waist, weight, and height measurements of adults between 20 and 60 years of age. Generalized additive location, scale and shape additive models with box-cox power exponential transformation to construct the curves. An internal validation was performed to ensure the models fit the data. Results. We studied 23,759 multiethnic adults from Colombia, 49.8% of whom were women. The waist-height index curves of men were visualized with slight curvature, while those of women appeared flatter. The median waist-height index increased continuously in both sexes: up to 45 years in women (0.45 to 0.49) and up to 55 years in men (0.44 to 0.49). In men, a value of 0.50 was maintained after 55 years, but not in women, since it remained at 0.50 until 53 years and thereafter increased to 0.51. Conclusion. The curves fitted with the box-cox power exponential distribution explained the increasing behavior of the waist-height index by age and sex and the predictive capacity of the model. The total increase in the median of the waist-height index by age and sex was similar and incremental (women: 0.45-0.51; men: 0.44-0.50).