Low- and high-dose aripiprazole augmentation and plasma levels of homovanillic acid in major depressive disorder: A randomized, open-label study.

OBJECTIVE: This randomized controlled study evaluated the efficacy of low-dose (LD) and high-dose (HD) aripiprazole augmentation in major depressive disorder. Additionally, we examined the relationship between clinical response and changes in plasma homovanillic acid (pHVA) levels during aripiprazole augmentation. METHODS: Thirty-one patients with inadequate response to antidepressants were randomized to receive adjunctive treatment with LD (3 mg/day, n = 17) or HD (up to 12 mg/day, n = 14) aripiprazole for 6 weeks. We evaluated the Montgomery-Åsberg Depression Rating Scale (MADRS) and measured pHVA at baseline, Week 2, and end point. RESULTS: Both LD and HD aripiprazole significantly decreased MADRS score after 6 weeks, and the response rate was higher in HD aripiprazole group at end point. HD aripiprazole significantly decreased MADRS score at Week 2 compared with LD aripiprazole (p = .015). There was a significant difference in changes in pHVA between responders and nonresponders, showing pHVA decreased significantly in responders at Week 2 (p = .044). CONCLUSIONS: Increasing aripiprazole from the early period appeared useful for immediate response, although caution is needed when increasing the dose >6 mg/day. pHVA may be a possible indicator of the response to aripiprazole augmentation. Caution is needed in interpreting these findings because of the small sample size.

Switching to lemborexant for the management of insomnia in mental disorders: the SLIM study.

STUDY OBJECTIVES: We conducted a retrospective study to investigate the efficacy and safety of switching from other hypnotics, including benzodiazepines and Z-drugs, suvorexant, ramelteon, mirtazapine, trazodone, and antipsychotics, to lemborexant, a dual orexin receptor antagonist, for 3 months. METHODS: Clinical data obtained from the medical records of 61 patients treated at the Horikoshi Psychosomatic Clinic between December 2020 and February 2022 were analyzed, including the Athens Insomnia Scale, Epworth Sleepiness Scale, and Perceived Deficits Questionnaire-5. The primary outcome was the mean change in Athens Insomnia Scale score after 3 months. Secondary outcomes were the mean changes in the Epworth Sleepiness Scale and Perceived Deficits Questionnaire-5 scores over 3 months. We also compared pre- and post-diazepam equivalents. RESULTS: The mean Athens Insomnia Scale score decreased over 3 months after switching to lemborexant (1 mo: -2.98 ± 5.19, P < .001; 2 mo: -3.20 ± 5.64, P < .001; 3 mo: -3.38 ± 5.61, P < .001). Mean Epworth Sleepiness Scale score did not change from baseline to 1 month (-0.49 ± 3.41, P = 0.27), 2 months (0.082 ± 4.62, P = .89), or 3 months (-0.64 ± 4.80, P = .30). Mean Perceived Deficits Questionnaire-5 score did improve from baseline to 1 month (-1.17 ± 2.47, P = .004), 2 months (-1.05 ± 2.97, P = .029), and 3 months (-1.24 ± 3.06, P = .013). There was also a reduction in the total diazepam equivalent (baseline vs 3 mo: 14.0 ± 20.2 vs 11.3 ± 20.6, P < .001). CONCLUSIONS: Our study showed that, by switching to lemborexant from other hypnotics, the risks associated with benzodiazepines and Z-drugs may be reduced. CITATION: Horikoshi S, Miura I, Suzuki Y, et al. Switching to lemborexant for the management of insomnia in mental disorders: the SLIM study. J Clin Sleep Med. 2023;19(10):1753-1758.

Effect of Switching to Brexpiprazole on Plasma Homovanillic Acid Levels and Antipsychotic-Related Side Effects in Patients with Schizophrenia or Schizoaffective Disorder.

OBJECTIVE: Although switching antipsychotics is a common strategy in the treatment of schizophrenia, caution is needed because of the risk of worsening of psychosis, particularly when switching to a dopamine D2 partial agonist. Homovanillic acid (HVA), a dopamine metabolite, is thought to be a possible indicator of the response to antipsychotics. We examined the effects of switching to brexpiprazole monotherapy from other antipsychotics on plasma HVA levels and side effects during maintenance treatment of schizophrenia. METHODS: The antipsychotics of 37 Japanese patients with schizophrenia or schizoaffective disorder were switched to brexpiprazole for the improvement of side effects. We evaluated clinical symptoms and extrapyramidal symptoms (EPS) and took fasting blood samples at baseline and endpoint (eight weeks after completing the switch) to measure plasma levels of HVA, prolactin, and metabolic parameters. RESULTS: Switching to brexpiprazole significantly decreased the Drug-Induced Extrapyramidal Symptoms Scale total score (p=0.008), prolactin levels (p<0.001), body weight (p=0.046), and body-mass index (p=0.034), and increased HDL cholesterol (p=0.008). On the other hand, switching to brexpiprazole did not change plasma levels of HVA or Positive and Negative Syndrome Scale scores. CONCLUSION: Switching to brexpiprazole significantly improved EPS, high prolactin levels, and metabolic side effects without elevating plasma HVA levels. Brexpiprazole may stabilize dopaminergic neural transmission and could be a useful strategy to decrease the burden in patients with schizophrenia during the maintenance phase. Because of the small sample size, further studies with larger sample sizes are needed to confirm and extend our results.