Chronic airflow limitation in a rural Indian population: etiology and relationship to body mass index

摘要

Purpose: Respiratory conditions remain a source of morbidity globally. As such, this study aimed to explore factors associated with the development of airflow obstruction (AFO) in a rural Indian setting and, using spirometry, study whether underweight is linked to AFO. Methods: Patients > 35 years old attending a rural clinic in West Bengal, India, took a structured questionnaire, had their body mass index (BMI) measured, and had spirometry performed by an ancillary health care worker. Results: In total, 416 patients completed the study; spirometry was acceptable for analysis of forced expiratory volume in 1 second in 286 cases (69%); 16% were noted to exhibit AFO. Factors associated with AFO were: increasing age (95% confidence interval (CI) 0.004–0.011; P = 0.005), smoking history (95% CI 0.07–0.174; P = 0.006), male gender (95% CI 0.19–0.47; P = 0.012), reduced BMI (95% CI 0.19–0.65; P = 0.02), and occupation (95% CI 0.12–0.84; P = 0.08). The mean BMI in males who currently smoked (n = 60; 19.29 kg/m2; standard deviation [SD] 3.46) was significantly lower than in male never smokers (n = 33; 21.15 kg/m2 SD 3.38; P < 0.001). AFO was observed in 27% of subjects with a BMI <18.5 kg/m2, falling to 13% with a BMI ≥18.5 kg/m2 (P = 0.013). AFO was observed in 11% of housewives, 22% of farm laborers, and 31% of cotton/jute workers (P = 0.035). Conclusion: In a rural Indian setting, AFO was related to advancing age, current or previous smoking, male gender, reduced BMI, and occupation. The data also suggest that being underweight is linked with AFO and that a mechanistic relationship exists between low body weight, smoking tobacco, and development of AFO.