The asthma–chronic obstructive pulmonary disease overlap syndrome: pharmacotherapeutic considerations

Abstract

Asthma–chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) is a commonly encountered yet loosely defined clinical entity. ACOS accounts for approximately 15–25% of the obstructive airway diseases and patients experience worse outcomes compared with asthma or COPD alone. Patients with ACOS have the combined risk factors of smoking and atopy, are generally younger than patients with COPD and experience acute exacerbations with higher frequency and greater severity than lone COPD. Pharmacotherapeutic considerations require an integrated approach, first to identify the relevant clinical phenotype(s), then to determine the best available therapy. The authors discuss the array of existing and emerging classes of drugs that could benefit those with ACOS and share their therapeutic approach. A consensus international definition of ACOS is needed to design prospective, randomized clinical trials to evaluate specific drug interventions on important outcomes such as lung function, acute exacerbations, quality of life and mortality.

Keywords::

• ACOS
• asthma
• asthma–COPD overlap syndrome
• bronchodilators
• chronic obstructive pulmonary disease
• corticosteroids
• novel therapies
• pharmacotherapy

Acknowledgements

The authors gratefully acknowledge Chue Xiong at the University of California, Davis School of Medicine (CA, USA), for her expert help in the preparation of the manuscript.

Financial & competing interests disclosure

S Louie has received financial support from AstraZeneca, Boehringer Ingelheim, Forest, Genentech, GSK and Merck. He has received speaker’s honoraria for asthma and COPD from Pfizer. TE Albertson has received support from Boehringer Ingelheim and GSK, and speaker’s honoraria for COPD from Pfizer. AA Zeki has received research support from the NIH, the Tobacco-Related Disease Research Program and the American Asthma Foundation. M Schivo has received research support from the NIH. M Avdalovic has received research support from Merck, Novartis and the NIH. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Notes

FEV₁: Forced expiratory volume in 1 s; FVC: Forced vital capacity; RAST: Radioallergosorbent test.

^†Asthma only.

^‡Chronic obstructive pulmonary disease only.

^§Both or asthma–chronic obstructive pulmonary disease overlap syndrome.

^¶Only fluticasone 250 µg/salmeterol 40 µg fixed combination dry powder inhaler and budesonide 160 µg/formoterol 4.5 µg fixed combination metered-dose inhaler are US FDA approved for chronic obstructive pulmonary disease in the USA.

^#FDA black box warning alert contraindicate their use as monotherapy in asthma patients and warning their use alone or in combination with other medications that cause asthma deaths.

ICS: Inhaled corticosteroids; LABA: Long-acting b2 agonist; LAMA: Long-acting muscarinic receptor antagonist; SABA: Short-acting b2 agonist; SAMA: Short-acting muscarinic receptor antagonist.