Breathlessness is a predominant symptom of chronic obstructive pulmonary disease (COPD), making it a valuable outcome in addition to lung function to assess treatment benefit. The phosphodiesterase-4 inhibitor roflumilast has been shown to provide small but significant improvements in dyspnea, as measured by the transition dyspnea index (TDI), in two 1-year studies in patients with severe to very severe COPD.
Patients and methods
To provide a more comprehensive assessment of the impact of roflumilast on dyspnea, post hoc analyses of four 1-year roflumilast studies (M2-111, M2-112, M2-124, and M2-125) in patients with moderate to very severe COPD were conducted.
In this pooled analysis (N=5,595), roflumilast significantly improved TDI focal scores versus placebo at week 52 (treatment difference, 0.327; P<0.0001). Roflumilast was associated with significantly greater TDI responders and significantly fewer TDI deteriorators (≥1-unit increase or decrease from baseline, respectively) versus placebo at week 52 (P<0.01, both); these significant differences were apparent by week 8 and maintained until study end (P<0.05, all). At study end, the postbronchodilator forced expiratory volume in 1 second improvement in TDI responders was significantly greater with roflumilast versus placebo (P<0.05). Similar to the overall population, improvements in TDI focal scores at week 52 were small but consistently significant over placebo in patients with chronic bronchitis, regardless of exacerbation history, concomitant treatment with short-acting muscarinic antagonists or long-acting β2-agonists, or pretreatment with inhaled corticosteroids.
This analysis shows that patients treated with roflumilast to reduce exacerbation risk may also experience small but significant improvements in dyspnea, with accompanying improvements in lung function.