Therapeutic drug monitoring of mirtazapine in a routine outpatient setting in Asian psychiatric patients

INTRODUCTION

Mirtazapine is an antidepressant that acts by enhancing serotonergic and noradrenergic neurotransmission. This study aimed to evaluate mirtazapine pharmacokinetic data from Korean psychiatric patients and to identify the potential factors affecting its steady-state concentration.

METHODS

A total of 337 samples of steady-state mirtazapine concentrations from 188 adult psychiatric outpatients were retrospectively evaluated. Serum mirtazapine concentrations were measured by high-performance liquid chromatography-tandem mass spectrometry.

RESULTS

Median mirtazapine concentration was 43.6 μg/L (164.37 nmol) at a daily dosage range of 7.5-60 mg. At the steady state, mirtazapine dose had a positive correlation with the drug concentration. Mean concentration-to-dose (C/D) ratio was 1.48 μg/L/mg/day (5.58 nmol/mg/day), which was higher than that in a previous study in Caucasian subjects. Age and paroxetine co-medication were positively associated with C/D ratio. Initial mirtazapine concentration and C/D ratio did not show an association with responsiveness in depressive patients.

DISCUSSION

This study presented the therapeutic drug monitoring data for mirtazapine and pharmacokinetic variations of mirtazapine in an Asian population. A further study could be helpful for clinical decision making based on the characteristics of patients.

Prognostic indicators of gastric carcinoma confined to the muscularis propria

AIMS

Gastric carcinoma confined to the muscularis propria (MPGC) is considered an intermediate-stage carcinoma. A method of discriminating between more favourable and less favourable prognostic groups of this entity is critically needed in dealing with this heterogeneous disease. The aim of this study was to examine the correlation between survival of patients with MPGC and its various clinicopathological parameters.

METHODS AND RESULTS

Various clinicopathological parameters were studied in 171 tissue samples including: macroscopic appearance, size, age, sex, stage, invasion depth, Lauren and Ming classifications, extent, lymphatic emboli and nodal metastasis. Tumours macroscopically resembling early gastric cancers, younger patient age, absence of lymphatic tumour emboli and lower stage were significantly associated with better prognosis of MPGC by univariate analysis. Tumours macroscopically resembling early gastric cancers, younger patient age and Lauren's diffuse type were significantly associated with a better prognosis of MPGC by multivariate analysis.

CONCLUSIONS

These indicators are practical parameters for predicting patient prognosis in clinical practice. The description of these parameters should be carefully noted in the final report and pathologists should evaluate the macroscopic appearance of MPGC.