Persistence with Selective Serotonin (Norepinephrine) Reuptake Inhibitors in Germany- a retrospective database analysis

Abstract Introduction Selective serotonin (norepinephrine) reuptake inhibitors (SS(N)RIs) are used in the treatment of depression. The aim of this study was to assess the persistence with SS(N)RIs in outpatients treated by general practitioners (GP) or psychiatrists (PSY) in Germany, and to investigate the association between persistence and the following factors: age, gender, specialty of the physician initiating treatment, initial molecule, and prior antidepressant prescription. Methodology A longitudinal pharmacy database (IMS LRx®) was used to identify patients (>18 years old) who had received an initial prescription (Rx) of an SS(N)RI between January 2014 and December 2016 (index date) from a GP or a PSY. Patients were only included if they had at least one year of pre-index observation time. The primary outcome was the rate of patients without SS(N)RI treatment discontinuation in the 12 months following the index date. Persistence was assessed using the Kaplan-Meier method. Cox regression was used to determine the impact of covariates on persistence. Results A total of 1,213,344 patients were eligible to be included (mean age: 55.9 years, 67% women). Twelve months after initiation of SS(N)RI therapy, 28.3% of patients were persistent. Higher age was significantly associated with a lower discontinuation risk. In addition, female gender, treatment initiation by a PSY, and treatment with other antidepressants at the index date were associated with a slightly higher persistence. There were significant associations for the different molecules; however, the absolute differences were small (below 5%). Conclusion The results show that the proportion of patients receiving long-term SS(N)RI therapy (at least 12 months) was low. Discontinuation depended mainly on age and, to a lesser degree, on gender, the specialty of the physician initiating treatment, other antidepressant prescription at the index date, and initial molecule.