When clinicians are concerned about an increased risk of suicidality induced by antidepressants in young patients, mirtazapine is considered a suitable option because of its low risk of provoking suicidality and its sedative effect. However, mirtazapine often needs to be discontinued or the dose reduced because of drowsiness, especially in young persons. This study retrospectively compared the clinical effects of mirtazapine in 16 young university students to those in 16 elderly patients with depression. Drowsiness was the most frequent side effect, and was observed more often in the students. Greater numbers of students also had their doses reduced or stopped using mirtazapine specifically because of oversedation. Furthermore, the final dose of mirtazapine was much lower in the student group even though the therapeutic effects were similar to those in the elderly group, suggesting that lower doses of mirtazapine should be administered to young depressed patients as starting or maintenance doses to avoid sedation and achieve a minimal level of therapeutic efficacy.

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Purpose: This study evaluated the impact of CYP2D6 polymorphism, and particularly CYP2D6*10 alleles, on the steady-state plasma concentrations of mirtazapine (MIR) and its metabolite N-desmethylmirtazapine (DMIR) in Japanese psychiatric patients.
Patients and Methods: The subjects were 75 Japanese patients treated with racemic MIR. The steady-state plasma concentrations of MIR and DMIR were measured using liquid chromatography. The CYP2D6 genotypes were determined by polymerase chain reaction. Three subjects whose plasma levels of MIR and DMIR were below the limit of detection were regarded as non-adherent and excluded, and 4 subjects having the CYP2D6*5 allele (CYP2D6*1/CYP2D6*5 and CYP2D6*2/CYP2D6*5 (n = 3) and CYP2D6*5/CYP2D6*10 (n = 1)) were excluded from the analysis in order to eliminate the effect of the CYP2D6*5 allele. Accordingly, data from 68 subjects were subjected to analysis.
Results: There were no significant differences in the plasma concentrations of MIR or DMIR (all corrected for dose and body weight) among different CYP2D6 genotypes. Multiple regression analysis also revealed that age affects MIR (corrected for dose and body weight) (p=0.079). Also, multiple regression analysis revealed that age correlated significantly to the plasma concentration of DMIR (corrected for dose and body weight) (p=0.026). Neither sex nor the number of CYP2D6*10 alleles were significant factors for either the plasma concentration of MIR (corrected for dose and body weight) or the plasma concentration of DMIR (corrected for dose and body weight).
Conclusion: CYP2D6*10 polymorphism did not significantly affect the steady-state plasma levels of MIR and DMIR in Japanese patients, but age had a significant effect on the plasma levels of DMIR.

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Purpose: Individuals with schizophrenia have a vastly reduced lifespan compared with the general population; comorbid cardiovascular disease (CVD) is the leading cause of death for them. Furthermore, these individuals are more likely to have metabolic syndrome-related disorders (MSDs), which increase CVD risk. We examined the medical records of long-term inpatients with schizophrenia to identify methods for preventing CVD and MSDs.
Method: A retrospective survey was conducted on 56 inpatients with schizophrenia. The prevalence rates of CVD and MSDs among inpatients with schizophrenia were compared with Japanese general population data from the 2010 National Health and Nutrition Examination Survey. Then, we compared the variables influencing CVD and MSDs between first- and second-generation antipsychotic drug groups.
Results: The prevalences of hyperlipidemia, diabetes mellitus, hypertension, myocardial infarction, and cerebral hemorrhage among individuals with schizophrenia were lower than those among the Japanese general population. This effect is likely attributable to the nursing care offered to individuals with schizophrenia, which includes dietary advice, moderate exercise support, and body weight and blood pressure measurement. Medication did not correlate with CVD or MSD prevalence.
Discussion: Long-term hospitalization appeared to be particularly useful in preventing CVD and MSDs; thus, nursing care equivalent to that provided in hospitals can reduce the prevalence of CVD and MSDs among patients with schizophrenia. Antipsychotic drugs might have only a minor influence on CVD and MSD prevalence with reliable nursing care. Japanese psychiatric personnel should attend to outpatients with schizophrenia, as this population is increasing and receives less care than do inpatients.

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