Medication adherence and its determinants among Brucellosis patients in China: A multi-center follow-up study

Background Brucellosis patients in China face challenges in adhering to prescribed oral medication regimens during home-based treatment. Improving adherence is critical for disease control and relapse prevention. However, systematic studies on medication adherence and its determinants among Chinese brucellosis patients remain scarce. This study aimed to assess medication adherence and identify its multilevel determinants in this population. Methods A multi-center study was conducted across six prefectures in China from December 2019 to August 2021. Demographic and clinical data were collected via questionnaires and medical records. Medication adherence was evaluated using the Chinese Morisky-8 Medication Adherence Scale (C-MMAS-8) at 6 and 12 weeks of treatment. Multilevel logistic regression models were employed to identify determinants of adherence. Results Among 820 enrolled patients, 801 (49.49 ± 11.51 years) and 426 (50.81 ± 11.11 years) completed follow-ups at 6 and 12 weeks, respectively. Adherence scores declined significantly from 8 (IQRs: 5.75–8), (53.18% optimal adherent) at 6 weeks to 7 (IQRs: 5.5–8), (41.31% optimal adherent) at 12 weeks ( P < 0.01). Quality of life scores correlated positively with adherence scores at both follow-ups ( r =0.28 and 0.21; P < 0.01). Compared with inner Mongolia, medication adherence in Xinjiang (OR=2.14, 95% CI: 1.01–4.51, P < 0.05) and Shandong (OR=2.94, 95% CI: 1.41–6.15, P < 0.01) was significantly high. Key determinants included social support (OR=1.06, 95% CI: 1.01–1.11), prior brucellosis episodes (OR=0.42, 95% CI: 0.18–0.99), and concomitant use of hepatoprotective medications (OR=0.39, 95% CI: 0.23–0.67). Conclusions Nearly half of brucellosis patients exhibited sub-optimal medication adherence, with adherence declining over time and significantly regional difference in optimal adherence. Enhancing social support, prioritizing patients with prior infection history for tailored education, and ensuring safe and rational medication use represent key strategies to improve adherence. Tailored interventions incorporating these elements are urgently needed to optimize disease management and reduce the risk of chronicity.