Correlation of FEV1/FEV6 with BODE Index, CAT Score and DLCO in COPD Patients

Abstract

Chronic Obstructive Pulmonary Disease is associated with progressive airflow limitation. Spirometry is one of the most important non-invasive tests that help in diagnosing airway obstruction. A Post bronchodilator FEV1/FVC ratio < 0.7 according to GOLD guidelines is considered to be diagnostic of COPD, wherein FEV1 is the forced expiratory volume in the first second, and FVC is the forced vital capacity which requires complete emptying of lungs that may require longer expiratory time and a more significant expiratory effort. The value of FEV1/FEV6 ratio is similar to the FEV1/FVC rate in diagnosing obstruction. FEV1/FEV6 is one such spirometric measurement which reduces the effort of expiration and helps in detecting the airway obstruction at the end of the sixth second during forceful exhalation thus serving as a natural, cost-effective bedside investigation that can be used in every health care facility for prompt diagnosis and management of the disease. FEV1/FEV6 can also be used to assess the prognosis of patients with COPD. It can even independently predict the reduction of lung function, rate of death and risk of carcinoma. The vitalograph is a smooth handheld device which helps in early detection of COPD in a quick, simple and reproducible manner. It not only displays the FEV1, FEV6 ratio and FEV1 per cent predicted but also provided information regarding the severity of COPD classification and lung age estimation. It can be used as a tool to avoid over diagnosis of COPD, especially in elderly patients. It has the advantage of requiring minimal instruction for use by non-respiratory specialists as well. This work concludes that FEV1/FEV6 can be used as a simple, cost-effective bedside investigation to diagnose COPD as an alternative to the conventional spirometry to detect undiagnosed airway obstruction in individuals with a low expiratory effort, especially in poor resource settings.