6주간 가변 용량의 Quetiapine으로 치료 받은 조현병 환자에서 약물 용량과 치료 효과의 관계

Dosing Pattern and Effectiveness of Quetiapine for Schizophrenic Patients Treated with Flexible Doses for 6 Weeks

quetiapine의 조현병 적정 치료 용량은 이전의 이중맹검 무작위 연구결과를 토대로 150~750 mg으로 알려져 있으나 실제 임상에서는 사용 용량이 이보다 높은 경향이 있다. 본 연구에서는 88개 정신과 병원 외래 조현병 환자를 대상으로 임상가의 판단에 따라 quetiapine 용량을 조절해 가며 6주 동안 치료했을 때 CGI-S로 치료 반응을 평가하였다. 특히 치료 전, 후 CGI-S 값과 6주째 quetiapine용량을 이용하여 군집 분석을 하였다. 총 841명의 환자가 연구에 참여하였고 6주째 CGI-I 점수가 2점 이하인 치료 반응 환자가 전체 환자의 55.9%였다. 특히 약물 치료 받은 적이 없는 환자의 경우는 더 좋은 치료 효과를 보였다. 그리고 6주째 약물 용량이 750~ 1,500 mg인 환자군이 다른 용량군(25~350, 400~500, 600~ 700 mg)보다 CGI-S 점수가 더 많이 감소하였다. 본 연구는 일부 환자의 경우 quetiapine 고용량이 증상 조절에 더 효과가 있을 수 있다는 것을 시사하였다.

Objective Recommended dosage of quetiapine for patients with schizophrenia is from 150 mg to 750 mg, which is based on randomized controlled study. But there are trends of increasing quetiapine dosage in clinical practice. Therefore, we evaluated the clinical aspect of schizophrenic patients who took quetiapine by naturalistic non-intervention study. Methods Schizophrenia outpatients in 88 mental hospitals were selected and 170 psychiatrists evaluated Clinical Global Impressions Scale for Severity (CGI-S) before starting quetiapine medication and CGI-S, Clinical Global Impressions Scale for Improvement (CGI-I), quetiapine dosage and medication compliance at 6 weeks after starting quetiapine medication. Overall efficacy and difference of efficacy between drug-naïve patients and medication-switch patients were evaluated. We clustered the patients into 4 groups by using cluster analysis with three variables such as quetiapine dose at week 6, baseline CGI-S, and end-point CGI-S. We compared clinical aspect of each cluster with analysis of variance. Result 841 patients were enrolled. Efficacy of quetiapine was replicated, and improvement rate defined as CGI-I ≤2 was 55.9%. Drug-naive patients show more improvement in CGI-I than medication-switch patients, and efficacy for patients with insufficient treatment was also reported. Dosage for each clustered group was 25-350 mg, 400-500 mg, 600-700 mg and 750-1,500 mg. 750-1,500 mg group shows more decrease in CGI-S than 400-500 mg group and 600-700 mg group. Conclusion This study suggests that there is a cluster of patients who take more benefits in reducing symptoms and show more compliance in high-dose quetiapine.