A Retrospective Observational Study to Understand Medication Utilization and Lines of Treatment in Patients with Insomnia Disorder

Background: Insomnia is a common sleep disorder, associated with multiple health concerns. Current medications for insomnia are associated with higher safety risks if clinical practice guidelines or monograph recommendations are not followed. This study aims to understand real-world prescribing practices among patients with insomnia in Canada, including medication utilization, potentially inappropriate medication use, cost incurred, and lines of treatment. Methods: This retrospective observational study utilized longitudinal drug claims data from 2018 to 2020 from the Canadian IQVIA National Private Drug Plan and Ontario Drug Benefit databases. Patients with any claims for medications approved for insomnia in Canada were identified. Four types of inappropriate medication usage were defined: (1) elevated daily dose; (2) extended duration of use for benzodiazepines (BZD) and/or Z-drugs; (3) combination use; and (4) opioid overlap with BZD and/or Z-drugs. Results: In 2019, 597,222 patients with insomnia were identified; 64% were female, with an average age of 55 years. Inappropriate medication use was noted in 52.5% of adult patients (aged 18-65 years) and 69.5% of senior patients (aged >65 years). Extended duration was the most common inappropriate medication usage category. The annual cost of medications for insomnia was $54.8 million, and $30.3 million (55.2%) met inappropriate medication use criteria. Conclusion: High prevalence of inappropriate medications usage in insomnia raises serious safety concerns for patients suffering from insomnia, particularly seniors, while also placing a substantial burden on the Canadian public and private health systems. This highlights an unmet need for better education regarding current guidelines and more effective and safer treatment options.