Assessment of Medication Regimen Complexity and Adherence in Chronic Obstructive Pulmonary Disease Patients at a Tertiary Care Teaching Hospital

ABSTRACT Background Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide. Medication regimen complexity and poor adherence are major barriers to optimal management, yet limited evidence exists in Nepal. This study aimed to assess medication regimen complexity and adherence among COPD patients attending a tertiary care hospital in Nepal. Methods A hospital‐based cross‐sectional study was conducted from November 2023 to May 2024 at a tertiary care teaching hospital in Nepal. A total of 174 COPD patients aged ≥40 years were enrolled using convenience sampling. Medication regimen complexity was assessed using the validated 65‐item Medication Regimen Complexity Index (MRCI), and adherence was evaluated with the Nepali version of the Morisky Medication Adherence Scale (MMAS‐8). Pearson's chi‐square test and binary logistic regression were performed at a 5% level of significance to examine factors associated with medication nonadherence. Results Of the total, 46.6% demonstrated suboptimal adherence, strongly associated with smoking (adjusted odds ratios [aOR]: 7.5; 95% CI: 2.82–19.90; p < 0.001) and alcohol use (aOR: 3.66; 95% CI: 1.578–8.49; p = 0.003). COPD regimens exhibited higher complexity (mean MRCI: 10.296 ± 5.4) than non‐COPD medications (3.66 ± 3.478). High COPD MRCI (aOR: 25.8; 95% CI: 14.7–38.5; p = 0.03) and high patient‐level MRCI (aOR: 15.6; 95% CI: 6.7–33.9; p < 0.001) were significant predictors of nonadherence. Conclusion COPD‐specific regimens were found to be more complex, and higher regimen complexity together with lifestyle factors, such as smoking and alcohol consumption, were strong determinants of nonadherence. Simplifying regimens through fixed‐dose combinations, pharmacist‐led interventions, and behavioral counseling may improve medication adherence and treatment outcomes in COPD patients.