Characteristics of pulmonary rehabilitation programs and their effects on exercise capacity and health related quality of life (HRQoL) in patients with interstitial lung disease: A systematic review and meta-analysis.

BACKGROUND

Interstitial Lung Disease (ILD) is characterized by dyspnoea, reduced exercise capacity and poor health related quality of life (HRQoL). The evidence to support the benefits of pulmonary rehabilitation (PR) on exercise capacity (EC) and HRQoL in this population is still limited. We aimed to determine the effect of the different PR components on exercise capacity and HRQoL in patients with ILD.

METHODS

We searched five databases (January 1990 to August 2024) using Population: ILD patients; Intervention: PR; Comparison: no PR; Outcomes: exercise capacity (e.g., 6-min walk test [6MWT] and HRQoL (e.g., St George's respiratory questionnaire [SGRQ]); Study type: randomised controlled trials (RCT). We used Cochrane risk-of-bias tool and GRADE to rate the quality of the evidence.

FINDINGS

We identified 11 RCTs (476 ILD patients; 8 countries). 10 studies provided data for exercise capacity (6MWD) and 7 studies for HRQoL (SGRQ). Both 6MWD and SGRQ improved ≥ their respective mínimum clinically-important difference of 45m and 7 units respectively, in studies where PR programme was i) >8 weeks (n = 5) [6MWD: MD 58m, 95 % CI 37 to 79, p < 0.00001; SGRQ: MD -9.7, 95 % CI -12.6 to -6.7, p < 0.00001], ii) fully supervised [6MWD (n = 5): MD 53.6m, 95 % CI 39 to 68, p < 0.00001; SGRQ (n = 2): MD -9.38, 95 % CI -12.93 to -5.84, p < 0.00001] and iii) incorporated high-intensity interval training (HIIT) (n = 2) [6MWD: MD 77m, 95 % CI 45 to 109, p < 0.00001; SGRQ: MD -10.3, 95 % CI -13.7 to -6.9, p < 0.00001] INTERPRETATION: PR programs of >8 weeks, fully supervised and incorporated HIIT had a better clinical impact on EC and HRQoL.