Correlation of Waist Circumference (WC) with Lung Age in Adult Male Smokers of Rural Western Rajasthan: A Cross-Sectional Study

Background: Independently, central obesity (abdominal adiposity) and tobacco smoking are major risk factors for pulmonary decline; but in their combined state, their effect on lung age—a marker of respiratory aging—remains underexplored in rural India. So, our study targeted to examine the joint impact of these two risk factors on lung age in adult males residing in rural Western Rajasthan. Aims and Objectives: To evaluate the correlation between Lung age and central obesity (waist circumference) among adult male smokers and to assess the individual and combined impact of central obesity and smoking on lung age. Materials & Methods: In this cross-sectional study, 271 adult males (18–47 years) from rural Western Rajasthan were classified into four groups by smoking status and obesity (i.e. Nonsmoker-Nonobese, Nonsmoker-Obese, Smoker-Nonobese & Smoker-Obese group). Waist circumference (WC) was calculated using standard anthropometry, and lung age was estimated from FEV₁ and height via the Morris and Temple equation. Data were analyzed using one-way ANOVA and Spearman’s correlation. Results: Mean lung age rose progressively from controls to the smoker–obese group, with significant intergroup differences in ANOVA [F(3,267) = 92.32, p < 0.001]. As per Spearman’s rho correlation, Lung-age was correlated positively with WC (rs = +0.433) and smoking status (rs = 0.587) (p ≤ 0.001 for both). Conclusion: Central obesity and smoking independently accelerate lung aging, with their combination exerting the greatest effect. Dual-targeted interventions are essential to preserve pulmonary health in rural populations. Key words: Lung age, Smoking, Central obesity, Waist circumference, Rural population.