Abstract
Background: The K-BILD questionnaire is an ILD health status tool. Its relationship with functional outcome measures has not been assessed.
Aims: Assess construct validity of K-BILD scores in an independent population compared to accepted measures including 6MWT.
Compare longitudinal change in K-BILD scores to physiological parameters.
Methods: Patients attending the Bristol ILD service with fibrotic ILDs completed K-BILD questionnaires, full lung function and exercise testing. A cohort of patients completed the K-BILD twice with an interval between to assess change. Results were compared by correlation coefficient.
Results:
Mean | SD | |
Age (yrs) | 71.1 | 11.2 |
KBILD total | 61.0 | 22.4 |
KBILD psych | 63.5 | 24.5 |
KBILD breathlessness | 47.2 | 29.2 |
KBILD chest symptoms | 68.4 | 22.9 |
FVC (%) | 84.0 | 22.8 |
DLCO (%) | 50.4 | 19.5 |
6MWD (m) | 292 | 89 |
Nadir So2 (%) | 87.4 | 5.0 |
175 patients, 58% IPF, 67.4% male, completed a K-BILD questionnaire. There was significant correlation between the KBILD and all physiological parameters, strongest between breathlessness domains and total score and 6MWT and TLCO, especially in IPF.
FVC | DLCO | 6MWD | Nadir So2 | |
KBILD total | 0.30* | 0.37* | 0.36* | 0.21 |
KBILD breathlessness | 0.35* | 0.47* | 0.42* | 0.24* |
IPF KBILD total | 0.23* | 0.38* | 0.26* | 0.42* |
IPF KBILD breathlessness | 0.31* | 0.48* | 0.37* | 0.43* |
Pearson co-efficients, *p<0.01
44 patients (84% IPF) completed 2 questionnaires (median interval 5.5 months). Mean K-BILD change was -3.7. K-BILD change and change in lung function correlated, but not exercise testing variables (FVC r=0.38, TLCO r=0.37, 6MWT r=0.20).
Conclusions: The K-BILD tool correlates well with physiological measures and is sensitive to change in lung function variables.
- Copyright ©the authors 2016