Continuous treatment with antidementia drugs in Germany 2003-2013: a retrospective database analysis

Continuous treatment is an important indicator of medication adherence in dementia. However, long-term studies in larger clinical settings are lacking, and little is known about moderating effects of patient and service characteristics.

Data from 12,910 outpatients with dementia (mean age 79.2 years; SD = 7.6 years) treated between January 2003 and December 2013 in Germany were included. Continuous treatment was analysed using Kaplan-Meier curves and log-rank tests. In addition, multivariate Cox regression models were fitted with continuous treatment as dependent variable and the predictors antidementia agent, age, gender, medical comorbidities, physician specialty, and health insurance status.

After one year of follow-up, nearly 60% of patients continued drug treatment. Donezepil (HR: 0.88; 95% CI: 0.82-0.95) and memantine (HR: 0.85; 0.79-0.91) patients were less likely to be discontinued treatment as compared to rivastigmine users. Patients were less likely to be discontinued if they were treated by specialist physicians as compared to general practitioners (HR: 0.44; 0.41-0.48). Younger male patients and patients who had private health insurance had a lower discontinuation risk. Regarding comorbidity, patients were more likely to be continuously treated with the index substance if a diagnosis of heart failure or hypertension had been diagnosed at baseline.

Our results imply that besides type of antidementia agent, involvement of a specialist in the complex process of prescribing antidementia drugs can provide meaningful benefits to patients, in terms of more disease-specific and continuous treatment.