Adherence to Acromegaly Treatment and Analysis of the Related Factors—A Real-World Study in Bulgaria

The purpose was to assess the level of medication adherence (MA) and related factors among individuals with acromegaly. The secondary goal was to assess the quality of life of patients and whether and how it correlates with the level of adherence. A prospective one-year study was conducted among patients with acromegaly diagnosed, treated, and monitored in the reference center for rare endocrine diseases in Bulgaria in 2021. Clinical data, patients reported outcomes, and health economics data were collected to define the predictors of non-adherence to medicines. Medication adherence level was assessed through a free Morisky–Green 4-item questionnaire. A total of 179 patients with acromegaly were observed. Approximately 62% were female, 50% were between 41 and 60 years, and the mean age at diagnosis was 40.4 years. The response rate to the questionnaires was 53% (n = 95; mean age 53.5 years, 73% female and 26% male). Patients with high levels of MA reported higher median values for the 36-Item Short Form Health Survey (SF-36) in comparison with those with low levels: 65.5 vs. 48.5 (p = 0.017). Similar results for EQ-5D-3L (3-level EuroQol 5D version) values and the level of MA were found: 0.656 vs. 0.796 (p = 0.0123). A low level of adherence was revealed in 34.7% of the patients, with no difference among different age groups. A significant positive determinant for adherence was years lived with acromegaly (OR = 5.625, 95% CI 1.7401–18.1832, p = 0.0039), as shorter duration was related to higher odds for high level of adherence. The current study demonstrates the importance of MA assessment for patients with acromegaly in Bulgaria. The medication adherence to the prescribed therapy among the observed group of patients with acromegaly varied as the percentage of adherent patients was around 65%. Still, there are low-adherent patients, and the responsible factors should be further investigated.