Dyspnea-induced Limitation (DYSLIM), a new self-administered concise questionnaire to evaluate dyspnea-related activity limitation in chronic respiratory diseases

Abstract

Background and aim: Few questionnaires are available for routine assessment of dyspnea. The study aimed to design a self-administered questionnaire assessing the impact of chronic dyspnea on daily activities, named DYSLIM (Dyspnea-induced Limitation).

Methods: The development followed 4 steps: 1: selection of relevant activities and related questions (focus groups); 2: clinical study: internal and concurrent validity vs. modified Medical Research Council (mMRC), Baseline Dyspnea Index (BDI) and Saint George Respiratory Questionnaire (SGRQ); 3: item reduction; 4: responsiveness. Eighteen activities (from eating to climbing stairs) were considered with 5 modalities for each: doing the task slowly, taking breaks, seeking assistance, changing habits, and activity avoidance. Each modality was graded from 5 (never) to 1 (very often). Validation study included 194 patients: COPD (FEV1 ≥ 50% pred: n = 40; FEV1 < 50% pred: n = 65); cystic fibrosis (n = 30), interstitial lung disease (n = 30), pulmonary hypertension (n = 29). Responsiveness was evaluated by post-pulmonary rehabilitation data in 52 COPD patients.

Results: Acceptability was high and short term (7 days) reproducibility was satisfactory (Kappa mostly above 0.7). Concurrent validity was high vs. mMRC (Spearman correlation coefficient, r = 0.71), BDI (r = - 0.75) and SGRQ (r = - 0.79). The reduced questionnaire with 8 activities (from cleaning to climbing stairs) and 3 modalities (slowly, seeking help, changing habits) showed a comparable validity and was chosen as the final short version. Effect size of rehabilitation was good for both the full (0.57) and short (0.51) versions. A significant correlation was also found between changes of SGRQ and DYSLIM post rehabilitation: r = - 0.68 and r = - 0.60 for full and reduced questionnaires, respectively.

Conclusion: The DYSLIM questionnaire appears promising for the evaluation of dyspnea-induced limitations in chronic respiratory diseases and seems suitable for use in various contexts.

Keywords: COPD; Cystic fibrosis; Dyspnea; Interstitial lung disease; Pulmonary hypertension; Questionnaire.