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.

Factors associated with the severity of delirium.

BACKGROUND: Various factors affecting the development of delirium have been identified. However, the associations between the severity of delirium and potentially related factors have not been adequately investigated. The aim of the present study was to explore factors associated with the severity of delirium and to identify the reversible contributing factors. METHODS: A total of 577 patients with delirium referred to the Department of Psychiatry during the 5 years from May 2015 to April 2020 at a general hospital were included. The Delirium Rating Scale-revised-98 (DRS-R-98) was used to measure the severity of delirium. Multiple regression analysis was used to determine whether individual factors were associated with the severity of delirium. RESULTS: Intensive care unit admission (p = 0.003), use of benzodiazepines (p = 0.01), dementia (p = 0.02), and older age (p = 0.045) were all positively associated the severity of delirium, while use of ß-blockers (p = 0.001) was negatively associated with the severity of delirium. CONCLUSIONS: Reversible contributing factors, that is use of benzodiazepines, should be avoided as much as possible, especially in elderly patients or patients with dementia or patients who need critical care in ICU. Reducing the dose of benzodiazepines or switching them to other drugs should be a priority.