Efficacy of indacaterol on quality of life and pulmonary function in patients with COPD and inhaler device preferences

Abstract

Background: Indacaterol is a novel, once-daily, inhaled, long-acting b2-agonist for patients with chronic obstructive pulmonary disease (COPD). The study objective was to evaluate the efficacy of indacaterol on quality of life and pulmonary function in patients with COPD in a real-world setting, and also to evaluate its inhaler device (Breezhaler®), which is important for both adherence and management.

Methods: Twenty-eight outpatients with COPD were treated with indacaterol (150 μg once daily for 8 weeks), and the effects on pulmonary function were evaluated using a questionnaire survey with the modified Medical Research Council (mMRC) dyspnea scale and COPD assessment test (CAT) before and after treatment. Similar investigations were also performed separately among different baseline medications. Moreover, original questionnaire surveys for indacaterol and its device were performed.

Results: Overall, mMRC dyspnea scale and CAT scores significantly improved (1.96±1.04 to 1.57±1.07 and 17.39±8.23 to 12.82±8.42, respectively; P<0.05). Significant improvements in forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) were also observed on pulmonary function tests (2.91±0.66 L to 3.07±0.65 L and 1.46±0.60 L to 1.58±0.59 L, respectively; P<0.05). Replacement therapy from salmeterol to indacaterol significantly improved mMRC and FVC values, but did not significantly improve CAT scores or other pulmonary functions. Add-on therapy with indacaterol significantly improved mMRC score, CAT score, FVC, and FEV1, regardless of whether tiotropium was used as a baseline treatment. All subjects in a questionnaire survey found the inhaler device easy to use. There were no serious adverse events leading to treatment discontinuation.

Conclusion: Indacaterol is thought to be effective and well tolerated as a bronchodilator for the management of COPD. Treatment with indacaterol in addition to a long-acting muscarinic antagonist was also useful.

Keywords: COPD; device; indacaterol; quality of life; respiratory function.

Figure 1

Comparison of mMRC dyspnea scale and CAT scores pre- and post-treatment with indacaterol. The mMRC dyspnea scale (A) and the CAT score (B) significantly improved after treatment with indacaterol (P=0.0013 and P=0.0003, respectively). Notes: Add-on group with indacaterol (n = 18) for gray lines. Replacement group with indacaterol (n = 10) for black lines. Abbreviations: CAT, chronic obstructive pulmonary disease assessment test; mMRC, modified Medical Research Council.

Figure 2

Comparison of scores for each item of the CAT questionnaire pre- and post-treatment with indacaterol. Scores for questions one to seven of the total of eight questions were significantly improved by treatment with indacaterol (*P<0.05 for each). Abbreviation: CAT, chronic obstructive pulmonary disease assessment test.

Figure 3

Pulmonary function tests pre- and post-treatment with indacaterol. The IC (A), FVC (B), FEV₁ (C), V₅₀ (D), V₂₅ (E), and V₅₀/V₂₅ (F) pulmonary functions were compared pre- and post-treatment with indacaterol. FVC, FEV₁, and V₂₅ were significantly improved by treatment with indacaterol (P<0.05 for each). Notes: Add-on group with indacaterol (n = 17) for gray lines. Replacement group with indacaterol (n = 10) for black lines. Abbreviations: IC, inspiratory capacity; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; V₂₅, flow at 25% forced vital capacity; V₅₀, flow at 50% forced vital capacity.