Factors Associated with Prescriptions for an Orexin Receptor Antagonist Among Japanese Patients with Insomnia: Analysis of a Nationwide Japanese Claims Database

BACKGROUND: Few studies have examined the prescribing patterns of orexin receptor antagonists (ORAs) in the real-world clinical setting in Japan. OBJECTIVE: We sought to analyze the factors associated with ORA prescriptions for patients with insomnia in Japan. METHODS: Outpatients (aged ≥ 20 to < 75 years old) prescribed one or more hypnotic for insomnia between April 1, 2018 and March 31, 2020 with continuous enrollment for ≥ 12 months were extracted from the JMDC Claims Database. We performed multivariable logistic regression to identify factors (patient demographics and psychiatric comorbidities) associated with ORA prescription in new or non-new users of hypnotics (patients without or with hypnotics prescription history, respectively). RESULTS: Of 58,907 new users, 11,589 (19.7%) were prescribed ORA at the index date. Male sex (odds ratio [OR] 1.17, 95% confidence interval [CI] 1.12–1.22) and presence of bipolar disorders (OR 1.36, 95% CI 1.20–1.55) were associated with greater odds of ORA prescription. Among 88,611 non-new users, 15,504 (17.5%) were prescribed ORA at the index date. Younger age and several psychiatric comorbidities, such as neurocognitive disorders (OR 1.64, 95% CI 1.15–2.35), substance use disorders (OR 1.19, 95% CI 1.05–1.35), bipolar disorders (OR 1.14, 95% CI 1.07–1.22), schizophrenia spectrum disorders (OR 1.07, 95% CI 1.01–1.14), and anxiety disorders (OR 1.05, 95% CI 1.00–1.10), were associated with greater odds of ORA prescription. CONCLUSION: This is the first study to determine the factors associated with ORA prescriptions in Japan. Our findings could help guide appropriate insomnia treatment using ORAs.