Objective:

To evaluate the efficacy of suvorexant in reducing the incidence of delirium in hospitalized older adults at high risk for the condition.

Approach:

• Study Design: A double-blind, placebo-controlled randomized clinical trial conducted at 50 hospitals in Japan.
• Participants: 203 participants aged 65 to 90 years with mild cognitive impairment, mild dementia, or a history of delirium.
• Intervention: Participants received either suvorexant (15 mg) or a placebo nightly for up to 7 days.
• Primary Outcome: Incidence of delirium diagnosed using DSM-5 criteria.

Key Findings:

• Delirium incidence was 16.8% in the suvorexant group vs 26.5% in the placebo group (P = .13).
• No statistical significance was reached for the primary endpoint.
• Post hoc analysis showed a significant difference in hyperactive and mixed delirium subtypes (10.9% vs 21.6%, P = .04).
• Adverse events were similar between groups, with some events occurring more frequently in the suvorexant group.
• The average age of participants was 81.5 years (SD 4.5) in the suvorexant group and 82.0 years (SD 4.9) in the placebo group.
• The suvorexant group consisted of 52 men (51.5%) and 49 women (48.5%), while the placebo group included 45 men (44.1%) and 57 women (55.9%).

Interpretation:

Further studies are needed to determine the usefulness of suvorexant in reducing delirium.

Limitations:

• Conducted exclusively in Japan, limiting generalizability.
• Majority of participants had mild cognitive impairment or mild dementia.
• The 15 mg dose used is the maximum approved dose for older adults in Japan but lower than in some other countries.

Conclusion:

Further studies are needed to determine the usefulness of suvorexant in reducing delirium, particularly with a hyperactive component.

Sources:

• JAMA Network Open