Clinical Characteristics Associated With Nightmares During Lemborexant Treatment in Psychiatric Patients

BACKGROUND: A dual orexin receptor antagonist, lemborexant (LEM) is widely prescribed for the treatment of insomnia, especially among patients with psychiatric disorders. However, LEM-induced nightmares may exacerbate existing psychiatric symptoms and lead to the discontinuation of treatment. Despite its still growing clinical application, few studies have identified risk factors associated with LEM-induced nightmares. The aim of this study was to elucidate the clinical factors associated with LEM-induced nightmares in clinical settings. PROCEDURES: This retrospective study included 327 psychiatric patients who were prescribed LEM at the University of Miyazaki Hospital between January 2020 and September 2024. Risk factors were identified by comparing demographic and clinical characteristics between patients who experienced nightmares (nightmare group) and those who did not (non-nightmare group). RESULTS: The incidence of nightmares (8.0%) exceeded the incidence reported in previous clinical trials. Multivariate logistic regression revealed that younger age (10 to 29 years), concomitant use of tandospirone, and switching from benzodiazepine drugs were significantly associated with an increased risk of nightmares. Receiver Operating Characteristic curve analysis indicated an age cutoff of ≤49 years for increased risk. Cox regression analysis further demonstrated that these factors were associated with earlier onset of nightmares following LEM initiation. CONCLUSIONS: This study revealed that patients aged 50 years or older who were prescribed LEM experienced a lower incidence of nightmares than younger patients. When prescribing LEM-particularly in younger patients, in combination with tandospirone, or following benzodiazepines discontinuation-clinicians should consider potential nightmares associated with LEM. These findings offer clinically meaningful insights for optimizing insomnia treatment while minimizing LEM-associated risks.