Correlation of Peak Expiratory Flow Rate (PEFR) with Waist-to-Hip Ratio (WHR) Among Adult Male Smokers in Rural Western Rajasthan: A Cross-Sectional Study

Background:Peak expiratory flow rate (PEFR) is an important pulmonary function test (PFT) parameter. Waist-to-hip ratio (WHR) is a reliable index of central obesity. Both the central obesity and smoking are well-recognized independent risk factors causing deterioration of pulmonary functions. Yet, limited studies have evaluated their combined impact, particularly in rural populations. Objective:To assess the relationship of PEFR with WHR in male smokers and determine the joint effect of central obesity and smoking on lung function. Methods:A cross-sectional study was conducted among 271 adult males (18–47 years) from rural Western Rajasthan. Participants were classified into four groups: Group I—Nonsmoker/Nonobese (control), Group II—Nonsmoker/Obese, Group III—Smoker/Nonobese, and Group IV—Smoker/Obese. WHR was calculated from waist and hip circumferences, and PEFR (L/s) was measured using computerized spirometry. Statistical analysis included ANOVA, Levene’s test for homogeneity of variances, Games–Howell post hoc, and Spearman’s correlation tests. Results:PEFR was lowest in the Smoker/Obese group, followed by Smoker/Nonobese and Nonsmoker/Obese, compared with controls. ANOVA showed a significant difference in PEFR across groups (p < 0.001). Spearman’s analysis demonstrated a significant inverse correlation of PEFR with both WHR (p < 0.001) and smoking status (p < 0.001). Conclusion:Central obesity and smoking exert additive adverse effects on pulmonary function, with the combined impact being more detrimental than either factor alone. Early detection and integrated preventive strategies are crucial in rural populations with limited healthcare access.