Cambios en el índice de masa corporal según estado de madurez en adolescentes de una región de Chile durante un periodo de 20 años

Introduction: Anthropometric indices are essential tools in the assessment of health status and can be useful to analyze changes over time. Objective: To determine if there are significant changes in body mass index (BMI) according to maturity status (MS) in adolescents over a 30-year interval. Methodology: A cohort study was designed in schoolchildren aged 11.0 to 17.0 years. The sample was composed of two cohorts corresponding to the year 1997 and 2017. The sample selection was probabilistic (random), for the 1997 cohort 939 adolescents were selected and for 2017 there were 1026 adolescents. Weight and height were assessed. BMI and MS were calculated from anthropometric variables. Results: Adolescents of both sexes in the 2017 cohort evidenced higher BMI relative to their 1997 counterparts. There were no significant differences in MS between the two cohorts. The correlation between BMI and MS in males increased from r= 0.25 (r²=0.062) to r= 0.27 (r²=0.067) over 20 years, while in females it was from r= 0.19 (r²= 0.036) to r= 0.26 (r²= 0.070). This reflects increases in BMI in both sexes, although slightly more in females than in males. Conclusion: This study verified a significant increase in BMI in all MS over a 20-year period, with a greater increase in women than in males. These findings highlight the urgency of intervening in this population to address the problem of overweight and obesity.