How often are antidepressants prescribed off-label among older adults in Germany? A claims data analysis.

Abstract

To estimate the extent of off-label prescribing of antidepressants in older adults and to characterize patients with off-label vs on-label prescriptions of antidepressants using a large German health claims database. Using data from the German Pharmacoepidemiological Research Database (GePaRD), we conducted a cross-sectional study in adults aged 65 years or older with a dispensation of an antidepressant between 1 January 2009 and 31 December 2015 after a period of 365 days without such a dispensation. We assessed the overall and annual proportion of off-label prescriptions of antidepressants by class and individual substance. Among 263 276 incident users of antidepressants, the proportion of off-label prescribing was 43.6% (95% CI 43.4-43.8%) with little variation between 2009 and 2015 (42.2-44.4%). The proportion of off-label use was higher in men (49%) than women (41%). While the proportion of off-label prescriptions was highest for tri- and tetracyclic antidepressants with 56.2% (amitriptyline 54.6%, maximum 65.9% for trimipramine), it amounted to 41.8% for selective serotonin reuptake inhibitors (citalopram 41.6%, maximum 46.0% for escitalopram) and was 51.2% for mirtazapine. Indicators of overall morbidity were similar in both groups, eg, pain was coded in 72% of off-label users vs 77% of on-label users (insomnia 20% vs 24%). Our study suggests a high prevalence of off-label antidepressant use among older adults in Germany, which was not restricted to certain classes of antidepressants or individual antidepressants. Given the unclear risk-benefit ratio, studies investigating the safety of off-label use among older adults for individual antidepressants are urgently needed.