Consistent improvement in health-related quality of life with tiotropium in patients with chronic obstructive pulmonary disease: Novel and conventional responder analyses

Abstract

Introduction: Improving health-related quality of life (HRQoL) in COPD patients is an important pharmacotherapeutic objective. This study investigated the extent, consistency, and durability of tiotropium maintenance therapy impact on HRQoL in moderate-to-very severe COPD.

Methods: Patients received once-daily tiotropium 18 μg (n = 5244) or placebo (n = 4799) via HandiHaler^® (10 trials), or once-daily tiotropium 5 μg (n = 2622) or placebo (n = 2618) via Respimat^® inhaler (3 trials). St George's Respiratory Questionnaire (SGRQ) total scores were measured at baseline, and 6 months (13 trials) and 1 year (9 trials) from treatment start. Adjusted mean differences between treatments for change from baseline in total scores were calculated at each time-point for each trial. Responder and deteriorator rates (decrease or increase in score ≥4 units from baseline, respectively), net benefit (responder rate increase plus deteriorator rate decrease), and cumulative improvement and deterioration were determined.

Results: Adjusted mean total score differences between treatments for change from baseline were significant (p < 0.05) in favor of tiotropium in 10/13 trials at 6 months and in 8/9 trials at 1 year. In all trials, estimated differences in responder rates between treatments favored tiotropium (significant [p < 0.05]: 5/13 trials at 6 months; 8/9 trials at 1 year). Net benefit favored tiotropium and cumulative improvement rates were consistently greater and deterioration rates consistently lower for tiotropium versus placebo.

Conclusions: Tiotropium maintenance therapy significantly and consistently improved HRQoL in moderate-to-very severe COPD patients in a durable manner. These results may provide a benchmark for assessing benefits on HRQoL of other COPD treatments.

Keywords: Chronic obstructive pulmonary disease (COPD); Clinical trials; Health-related quality of life; Responder and deteriorator rates; St George's Respiratory Questionnaire (SGRQ); Tiotropium.