Prevalence and etiological profile of chronic obstructive pulmonary disease in nonsmokers.

Abstract

Background:Tobacco smoking has been recognized as the most important risk factor for chronic obstructive pulmonary disease (COPD) for a long time, but recent studies have shown that nonsmokers also contribute to a significant proportion of COPD. This study was performed to find out the proportion of nonsmoker individuals among COPD patients and to determine various etiologies in nonsmoker COPD patients.Materials and Methods:This study was an observational cross-sectional study conducted in Department of Pulmonary Medicine, MLN Medical College, Allahabad. A total of 200 COPD patients, aged >18 years of either gender with COPD, diagnosed by clinical and spirometric criteria (GOLD guideline) were included in the study.Results:Of the 200 COPD patients, the proportion of nonsmoker patients was 56.5%, and the smoker was 43.5%. Among 113 nonsmoker COPD patients, maximum number of patients (69.03%) belonged to low socioeconomic status but most important and statistically significant risk factor was exposure to biomass smoke (53.98%), other significant risk factors were treated pulmonary tuberculosis (32.74%), and long-standing asthma (14.16%). Risk factors that were not statistically significant were occupational exposure (9.73%), exposure to outdoor air pollution (3.54%), and lower respiratory tract infection during childhood (1.77%). The patients who were exposed to more than one risk factors, developed COPD at an earlier age.Conclusions:This study revealed that nonsmokers contribute a significant proportion of COPD patients. Multiple risk factors other than smoking also play a major role in the development of COPD, particularly exposure to biomass smoke, treated pulmonary tuberculosis, and long-standing asthma.