Maximal Voluntary Ventilation in Obese and Non-Obese Rural Adolescents and its Association with Fat Mass Index- Analytical Cross-Sectional Study

Introduction: Childhood obesity is a growing public health concern, yet limited research has examined its impact on the cardiopulmonary system, particularly in rural populations and across different age groups. Excess body fat in overweight and obese individuals can lead to a restrictive breathing pattern, reduced lung volumes, and decreased cardiopulmonary endurance, increasing the risk of related diseases. Pulmonary function tests, such as spirometry and maximum voluntary ventilation (MVV), provide valuable insights into respiratory capacity. While BMI is widely used to assess weight status, the Fat Mass Index (FMI) offers a more precise measure of adiposity. However, This study aims to evaluate the effect of obesity and age on pulmonary function measurements among obese and non-obese children and adolescents, and to examine the correlation between fat mass index and respiratory parameters in this population.  Methods: This analytical cross-sectional study recruited eighty adolescents (12–19 years) from rural India were classified as obese (n=40) or non-obese (n=40) using WHO BMI-for-age standards. MVV was assessed by spirometry (ATS guidelines) and FMI by validated equations. Data were analyzed using Shapiro–Wilk, Mann–Whitney U, and Spearman’s correlation.  Results: Obese adolescents showed significantly lower MVV than non-obese peers [72.30 L/min (IQR 63.35–79.70) vs. 96.25 L/min (IQR 86.40–109.75); median difference = 23.95; U = 189.5, p < 0.01]. FMI correlated moderately and inversely with MVV in the obese group (ρ = –0.579, p < 0.01), but no significant association was observed in non-obese participants (ρ = 0.261, p > 0.05).  Conclusion: This study concludes that obesity significantly impairs pulmonary function in adolescents, with lower MVV values in obese participants and a moderate negative correlation between MVV and FMI. FMI assessment may aid early detection of respiratory compromise.