Significant decrease in delirium referrals after changing hypnotic from benzodiazepine to suvorexant.

BACKGROUND: The use of benzodiazepines (BZDs) causes delirium, especially in elderly people. For this reason, suvorexant has been recommended as the first-line hypnotic in elderly patients. The aim of this study was to determine whether the first-line use of suvorexant, instead of BZDs, decreases referrals for delirium in elderly patients.

METHODS: Since May 2016 at Nagoya Ekisaikai Hospital, suvorexant has been recommended as the first-line hypnotic instead of BZDs. In May 2017, suvorexant was adopted as the first-line hypnotic. The number of delirium cases referred to psychiatry was compared among three consecutive periods: period A (May 2015-April 2016), during which BZDs were mainly used for insomnia; period B (May 2016-April 2017), during which the use of suvorexant was recommended instead of BZDs; and period C (May 2017-April 2018), during which suvorexant was principally adopted as the first-line hypnotic for insomnia. Potential confounding factors that may affect the development of delirium were also examined during the three periods.

RESULTS: The number of delirium referral cases in elderly patients in each period decreased, from 133 in period A to 86 in period B and 53 in period C. The rate of delirium referral cases decreased significantly every year (P = 9.02 × 10-10 ). Almost no significant confounding factors other than hypnotics were detected during the three periods.

CONCLUSION: The referrals for delirium in elderly patients decreased significantly after the hypnotic was changed from BZDs to suvorexant.