Hypnotic prescription trends and patterns for the treatment of insomnia in Japan: analysis of a nationwide Japanese claims database

Background: There is limited consensus regarding the optimal treatment of insomnia. The recent introduction of orexin receptor antagonists (ORA) has increased the available treatment options. However, the prescribing patterns of hypnotics in Japan have not been comprehensively assessed. We performed analyses of a claims database to investigate the real-world use of hypnotics for treating insomnia in Japan.

Methods: Data were retrieved for outpatients (aged ≥ 20 to < 75 years old) prescribed ≥ 1 hypnotic for a diagnosis of insomnia between April 1^st, 2009 and March 31^st, 2020, with ≥ 12 months of continuous enrolment in the JMDC Claims Database. Patients were classified as new or long-term users of hypnotics. Long-term use was defined as prescription of the same mechanism of action (MOA) for ≥ 180 days. We analyzed the trends (2010-2019) and patterns (2018-2019) in hypnotics prescriptions.

Results: We analyzed data for 130,177 new and 91,215 long-term users (2010-2019). Most new users were prescribed one MOA per year (97.1%-97.9%). In 2010, GABA_A-receptor agonists (benzodiazepines [BZD] or z-drugs) were prescribed to 94.0% of new users. Prescriptions for BZD declined from 54.8% of patients in 2010 to 30.5% in 2019, whereas z-drug prescriptions remained stable (~ 40%). Prescriptions for melatonin receptor agonist increased slightly (3.2% to 6.3%). Prescriptions for ORA increased over this time from 0% to 20.2%. Prescriptions for BZD alone among long-term users decreased steadily from 68.3% in 2010 to 49.7% in 2019. Prescriptions for ORA were lower among long-term users (0% in 2010, 4.3% in 2019) relative to new users. Using data from 2018-2019, multiple (≥ 2) MOAs were prescribed to a higher proportion of long-term (18.2%) than new (2.8%) users. The distribution of MOAs according to psychiatric comorbidities, segmented by age or sex, revealed higher proportions of BZD prescriptions in elderly (new and long-term users) and male (new users) patients in all comorbidity segments.

Conclusion: Prescriptions for hypnotics among new and long-term users in Japan showed distinct patterns and trends. Further understanding of the treatment options for insomnia with accumulating evidence for the risk-benefit balance might be beneficial for physicians prescribing hypnotics in real-world settings.