Abstract
Our study aimed to examine medication adherence (MA) to tadalafil 5 mg once daily (OaD) in patients undergoing treatment for erectile dysfunction (ED) and to identify factors contributing to potential drug noncompliance. This cross-sectional study included 233 patients diagnosed with ED. Sociodemographic and clinical data were recorded. MA was assessed using the Medication Adherence Report Scale (MARS). Additionally, the Brief Illness Perception Questionnaire (B-IPQ), the Beliefs about Medicines Questionnaire (BMQ), and the International Index of Erectile Function (IIEF) were employed to evaluate patients' perceptions and beliefs regarding their condition and treatment. The influence of these factors on MA was thoroughly analyzed. High MA was reported in 136 (58.4%) of 233 patients. Factors, such as education level, monthly income, frequency of medical examinations, smoking habits, and a history of radical pelvic surgery, were found to influence MA (p < 0.05) significantly. Multivariate analysis identified monthly income and radical pelvic surgery history as statistically significant predictors of adherence (p ≤ 0.05). Additionally, adherence was significantly associated with IIEF scores, five items on the B-IPQ, and the BMQ subscales, including specific concerns, necessity, and general harm (p < 0.05). Tadalafil OaD demonstrates acceptable rates of MA in the treatment of ED. Socioeconomic and clinical factors, patients' cognitive and sensory status, and perceptions regarding medications and healthcare providers significantly influence adherence. Physicians should exercise caution when prescribing tadalafil 5 mg OaD to patients with lower socioeconomic status, as they may be at higher risk for reduced MA.