Objectives: Polypharmacy and multimorbidity in chronic obstructive pulmonary disease (COPD) are highly prevalent, with potential associations with worse COPD outcomes. The aim of this study was to identify the clinical characteristics and outcomes of polypharmacy, investigate the relationship of polypharmacy with health status and exacerbations and assess the prevalence of inappropriate medication (PIM), risk of adverse drug reactions (ADRs) and drug-to-drug interactions in COPD patients.
Methods: A total of 245 COPD patients were enrolled from primary care in Crete, Greece. Patients completed a questionnaire and the COPD Assessment Test (CAT). Multimorbidity was defined as having two or more comorbidities and polypharmacy was defined as taking five or more drugs per day.
Results: Most of COPD patients (77.0%) and the majority (83.6%) of elderly (≥65 years) had multimorbidity, while polypharmacy was evident in 55.2% of all patients and 62.4% in elderly. After adjustments for age, gender and pack-years, polypharmacy was associated with CAT ≥ 10, multimorbidity, several cardiometabolic diseases, cancer and depression-anxiety and prostate disorders (all p values > 0.05). PIMs were found in 9.6% of subjects aged ≥65 years and were mainly mental health medication. Due to coadministration of medications, 22.3% of the population were at cumulative risk for falls, 17% for constipation and 12.8% for cardiovascular events. Finally, 15 pairs of drug-to-drug interactions were identified in 11.5% of patients.
Conclusion: Our data suggest that polypharmacy is highly prevalent and associated with worse health status and prescription risks in COPD patients. These findings potentially introduce an additional challenge on effective management of these patients.
Keywords: adverse drug reactions (ADRs); chronic obstructive pulmonary disease; drug-to-drug interactions; multimorbidity; polypharmacy; potentially inappropriate medication (PIM).
© 2021 John Wiley & Sons Ltd.