Assessment of health status and its correlation with lung function in patients with chronic obstructive pulmonary disease: a study from a tertiary care center in north India

The Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2023 recommends a comprehensive multidimensional assessment for patients with chronic obstructive pulmonary disease (COPD) and stresses the need for evaluation of their health status and quality of life (QOL). The COPD assessment test (CAT), clinical COPD questionnaire (CCQ), and St. George respiratory questionnaire (SGRQ) are recommended by GOLD for such assessments. However, their correlation with spirometry in the Indian population is not known. Other similar questionnaires like the COPD and sleep impact scale (CASIS), functional performance inventory-short form (FPI-SF), and COPD and asthma fatigue scale (CAFS), though used internationally as a research tool, are still in the offspring stage and have never been used in India. A cross-sectional study was hence conducted in the Department of Pulmonary Medicine, Government Medical College, Patiala, Punjab, India, on 100 COPD patients. Patients were assessed for health status and QOL by CAT, CCQ, SGRQ, CASIS, FPI-SF, and CAFS. The relationship between these questionnaires and airflow limitations was investigated. The majority of the patients were males (n=97), >50 years of age (n=83), illiterate (n=72), had moderate/severe COPD, and belonged to group B (n=66). The mean value of forced expiratory volume in one second (FeV₁) decreased with a deterioration in CAT and CCQ score grouping (p<0.001). Patients with poorer CAT and CCQ scores belonged to higher GOLD grades (k=0.33, p<0.001). The correlation of health-related quality of life (HRQL) questionnaires among each other, with FEV₁ predicted and with GOLD grade, was strong to very strong in most of the comparisons (p<0.01 in the majority). On comparison of GOLD grade with mean scores of HRQL questionnaires, it was seen that with the increase in GOLD grading from 1 to 4, the mean values of CAT, CCQ, SGRQ, CASIS, FPI-SF, and CAFS also deteriorated (p<0.001, p<0.001, p<0.001, p<0.005, p<0.001 and p<0.001, respectively). Various easy-to-use HRQL scores should be routinely used in outpatient departments for a comprehensive assessment of COPD patients. These questionnaires, in combination with clinical features, can help in providing a rough estimate of the severity of the disease in places where lung function assessments are not readily available.