The Association Between Medication Adherence and Health-Related Quality of Life in Patients with COPD: A Cross-Sectional Study.

Purpose: Chronic obstructive pulmonary disease (COPD) is a progressive respiratory condition with debilitating manifestations that adversely affect patients' health-related quality of life (HRQoL). The clinical course is complicated by patients' low medication adherence level. Low adherence and poor HRQoL are linked to unfavorable disease outcomes. Although many factors affect adherence and HRQoL in COPD, the impact of adherence on HRQoL remain controversial. This study aimed to measure medication adherence and its impact on HRQoL in patients with COPD. Patients and Methods: This cross-sectional observational study included patients with COPD from two health centers in Riyadh, Saudi Arabia. Patients were identified using the medical database and only those fulfilling the GOLD 2020 criteria for COPD diagnosis were recruited. Data were collected via phone interviews and included sociodemographic information, the level of medication adherence assessed using the 5-item Medication Adherence Report Scale (MARS-5), and the HRQoL measured using the St. George Respiratory Questionnaire for COPD (SGRQ-C). Simple and multiple-regression analysis was used to study the factors affecting both parameters and the relation between adherence and HRQoL. Results: The mean MARS-5 score was 21.17± 4.8 (mean ± SD) with only 56.4% of patients with COPD reporting high adherence to their medications. The average total SGRQ score was 51.35 ± 23.82 indicating low HRQoL. Using multiple-regression analysis, comorbidity and intermediate disease duration were associated with lower adherence, while older age, female gender, polypharmacy, and concomitant hypertension predicted lower HRQoL. Moreover, higher adherence to medications was associated with higher overall HRQoL in patients with COPD. Conclusion: Patients with COPD have low medication adherence and low HRQoL. Several patient-, disease-, and therapy-related factors were shown to affect both outcomes; however, higher adherence to medication per se was associated with higher HRQoL in patients with COPD.