The responsiveness of the depression, anxiety and stress-21 items scale to pulmonary rehabilitation program

Abstract

Introduction To date there are no studies that examined the responsiveness of the Depression, Anxiety and Stress scale – 21 items (DASS-21) in any intervention in patients with COPD.

Aims We evaluated the responsiveness of the DASS-21 scale in an eight-week pulmonary rehabilitation (PR) program.

Methods We recruited 192 patients with COPD who were clinically stable and had a percent predicted FEV₁ <70% completed 8-week community-based multidisciplinary PR. The duration of the program was 2-hours per/week (1-hour exercise and 1-hour education). Pre and post-rehabilitation outcome measures were evaluated using the DASS-21 scale, the incremental shuttle walk test (ISWT), the St-Georges Respiratory Questionnaire (SGRQ) and the Medical Research Council scale (MRC). Anxiety was measured by the Anxiety Inventory for Respiratory disease scale (AIR).

Results The mean (SD) age was 71(8.4) years. The DASS-21 scale was responsive to PR with a mean change pre versus post scores for depression [8.67 vs.7.01 t= 3.26 p< 0.001], for anxiety [8.55 vs. 7.01, t = 2.81 p<0.005], for stress [9.88 vs.7.69, t = 3.99 p<0.001] following PR. Table 1 shows change in DASS-21 items in relation to clinically relevant variables following PR.

Conclusion The DASS-21 items scale is responsive to change following 8-weeks PR in patients with COPD. Further studies are needed in long-term follow-up.