Correlation between Forced Expiratory Volume in First Second (FEV1) And 6 Minute Walk Distance In Moderate, Severe and Very Severe Chronic Obstructive Pulmonary Disease

Abstract

Relation between 6 minute walk test and spirometric parameters [FEV1 and FVC] in patients with COPD is investigated. There is no published data in India in this respect. Hospital based cross sectional study. Clinical COPD questionnaire score, Forced expiratory volume in first second (FEV1) and Forced expiratory volume (FVC), 6 minute walk distance and 6 minute walk work were calculated and compared. Data was analyzed by SPSS 11. It was observed that 11.1 % had overall clinical copd questionnaire (CCQ) score of more than 3; 62.2% had baseline PaO2 between 60-80 mm Hg;88.9% had baseline PaCO2 lower than or equal to 45 mm Hg; 53.3% had severe COPD according to GOLD spirometry criteria;13.3% had complication of Pulmonary artery hypertension; 64.5% walked more than 300 meters distance and 21.1% (8) of patients with severe copd had significant desaturation during walk test. There was low positive correlation with no statistical significance between FEV1 and 6 MWD (r= 0.280, p= 0.062) and between FVC and 6 minute walk distance(r= 0.289, p= 0.055). Demographic parameters like age, BMI, smoking score, spirometry and baseline paco2 were not correlating with 6 minute walk distance. BMI and FEV1 (forced expiratory volume) were more correlating with 6 minute walk work. Severity of airway obstruction or pulmonary artery hypertension was not predicting significant desaturation during walk test. Measuring walk distance alone is not sufficient for assessment of severity and functional status of COPD the patients. 6 minute walk work, which is the product of walk distance and body weight, is more correlating with severity of the disease.

Six-Minute Walk Test and its Correlation with Spirometry in Stable COPD Patients

“…Smoking, similar to many previous studies, was determined to be the most important predisposing factor for the development of COPD and was present in 70.34% of the cases. 12,14,15 COPD among non-smokers is an emerging entity and has been reported with variable frequency. The disease in this sub-group has been mainly attributed to air pollution.…”

“…Similar reports are available from previous studies as well. 11 12 A higher incidence among males could be attributed to smoking and occupational exposures. The PLATINO study has reported an increased prevalence of COPD among males.…”

“…Smoking, similar to many previous studies, was determined to be the most important predisposing factor for the development of COPD and was present in 70.34% of the cases. 12 14 15…”

Association between Emergency Visits with Acute Exacerbation and Exercise Performance in Chronic Obstructive Pulmonary Disease

“…The six-minute walk test is the most appropriate, simple, and reliable test for evaluation of exercise tolerance (29). A strong positive correlation has been determined between the six-minute walk test and FEV 1 (10,11). Another study that determined the correlation between the six-minute walk test and spirometric parameters stated that the walk test can be used to monitor alterations in pulmonary function in patients with severe and very severe COPD (34).…”

“…this test allows simultaneous evaluation of the patient's pulmonary, cardiovascular, musculoskeletal, and neuromuscular systems (11,12).…”