Introduction Spirometry remains the cornerstone in the diagnosis of Chronic Obstructive Pulmonary Disease (COPD). Little is known regarding the determinants and prevalence of COPD in rural India. We undertook a population-based study in Howrah District, West Bengal,India at a community-based primary care clinic of a voluntary organisation to test the feasibility of spirometric estimation of the prevalence of COPD.
Methods Spirometry was performed on all adults >35 years attending the clinic. Questionnaire data (capturing respiratory symptoms, occupation, tobacco smoking history, indoor stove use) were gathered for each subject. All spirometric data were examined by an independent UK-based clinical scientist.
Results Spirometry was performed in 315 patients over 3 months; 18% (58/315) of measurements were deemed good quality as per ERS guidelines; 45% (143/315) had the correct shaped curve; hence 64% (201/315) of all spirometries were deemed adequate for FEV1 analysis. Poor quality traces were noted in 36% (n=114) and hence were excluded from analysis. Of the adequate spirometries (n=201, mean age 51 years (SD 12.1); 39% male), 84 (42%) were normal, 102 (51%) exhibited mild airflow obstruction, 12 (6%) moderate airflow obstruction and 3 (1.5%) severe airflow obstruction according to British guidelines. Difference in FEV1% predicted between never/ex smokers and current smokers was significant (p=0.029). Indoor stove use was ubiquitous in this population and did not correlate with FEV1 percent predicted.
Conclusion In a rural Indian setting, valid spirometry can be obtained in two-thirds of adult patients attending a community clinic with 58% of patients in this sample exhibiting at least mild COPD with a history of current smoking being associated with the development of airflow obstruction.