Introduction The King's brief interstitial lung disease questionnaire (K-BILD) is a recently developed and validated 15 item HRQOL questionnaire comprising of 3 health domains (psychological, breathlessness and activities, and chest symptoms) and an overall HRQOL score. We set out to evaluate HRQOL in a large group of patients with interstitial lung diseases (ILD's) and determine the factors that influence it.
Methods 219 patients with ILD (60 idiopathic pulmonary fibrosis (IPF), 81 connective tissue associated ILD, 23 idiopathic non-specific interstitial pneumonitis (NSIP), 21 hypersensitivity pneumonitis, 10 organising pneumonia, 24 other) attending ILD clinics at King's College and Royal Brompton Hospitals completed the K-BILD. The K-BILD Scores range from 0 to 100, with a higher score representing a better HRQOL. Demographic data, immunosuppressant medication, long-term oxygen therapy use, multi-disciplinary team ILD diagnosis and lung function were recorded.
Results Patients had a mean (SEM) age of 60 (1) years, 75% of patients were Caucasian, 60% were females, mean (SEM) VC% predicted was 80 (24) % and TLCO % predicted was 47 (18)%. HRQOL was impaired in all domains, mean (SEM) scores: psychological 62 (2), breathlessness and activities 43 (2), chest symptoms 67 (2), total 59 (2). There were no significant associations between overall HRQOL and age (r=−0.007) or gender (p=0.13). There was a modest correlation between HRQOL and lung function (Abstract S133 table 1). HRQOL was significantly lower in IPF patients compared to other ILD's (total score 51 (3) vs 62 (2); p<0.01), those with UIP pattern vs NSIP (total score 51 (3) vs 62 (3); p<0.01) and those prescribed long-term oxygen therapy (total score 38 (4) vs 63 (2); p<0.01). IPF patients prescribed immunosuppressant medication had significantly worse overall HRQOL (48 (4) vs 74 (8); p=0.02). There was no significant difference between CTD-NSIP patients compared with idiopathic NSIP (total score 62 (3) vs 62 (5); p=0.91).
Conclusions HRQOL is impaired in patients with ILD. The type of ILD, immunosuppressant medication, and lung function all influence HRQOL. This study provides further clinical validation of the K-BILD.