Common use of high doses of antipsychotic medications in older Asian patients with schizophrenia (2001-2009).
OBJECTIVE
This study aimed to examine the use of high doses of antipsychotic medications (≥600 mg/day chlorpromazine equivalent) in older Asian patients with schizophrenia and its demographic and clinical correlates.


METHODS
Information on hospitalized patients with schizophrenia aged ≥50 years was extracted from the database of the Research on Asian Psychotropic Prescription Patterns study (2001-2009). Data on 2203 patients in six Asian countries and territories, including China, Hong Kong, Japan, Korea, Singapore and Taiwan, were analyzed. Socio-demographic and clinical characteristics and antipsychotic prescriptions were recorded.


RESULTS
The frequency for high-dose antipsychotic medications was 36.0% overall, with 38.4% in 2001, 33.3% in 2004 and 36.0% in 2009. Multiple logistic regression analysis of the whole sample showed that compared to patients receiving low-medium antipsychotic doses, those on high doses had a longer illness duration (odds ratio (OR): 2.0, 95% confidence interval (CI):1.2-3.3, p = 0.008), were more likely in the 50-59-year group (OR: 0.95, 95% CI: 0.94-0.97, p < 0.001), more often had current positive (OR: 1.5, 95% CI: 1.2-1.8, p < 0.001) or negative symptoms (OR: 1.3, 95% CI: 1.03-1.6, p = 0.03), and more commonly received antipsychotic polypharmacy (OR: 5.3, 95% CI: 4.1-6.7, p < 0.001). Extrapyramidal symptoms (p = 0.25) and tardive dyskinesia (p = 0.92) were not more frequent in the high-dose group.


CONCLUSIONS
High doses of antipsychotic medications were used in more than one third of older Asian patients with schizophrenia. The reasons for the frequent use of high antipsychotic doses in older Asian patients warrant further investigation.
Department of Psychiatry, Chinese University of Hong Kong, Hong Kong, China; Beijing Anding Hospital, Capital Medical University, Beijing, China.
Yu-Tao
YT
Xiang
Yan
Y
Li
Christoph U
CU
Correll
Gabor S
GS
Ungvari
Helen F K
HF
Chiu
Kelly Y C
KY
Lai
Quan-Sheng
QS
Tang
Wei
W
Hao
Tian-Mei
TM
Si
Chuan-Yue
CY
Wang
Edwin H M
EH
Lee
Yan-Ling
YL
He
Shu-Yu
SY
Yang
Mian-Yoon
MY
Chong
Ee-Heok
EH
Kua
Senta
S
Fujii
Kang
K
Sim
Michael K H
MK
Yong
Jitendra K
JK
Trivedi
Eun-Kee
EK
Chung
Pichet
P
Udomratn
Kok-Yoon
KY
Chee
Norman
N
Sartorius
Chay-Hoon
CH
Tan
Naotaka
N
Shinfuku
D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D014150:Antipsychotic Agents / Q000008:administration & dosage*; D044466:Asian People; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data; D012559:Schizophrenia / Q000188:drug therapy* / Q000208:ethnology; D012959:Socioeconomic Factors
D014150:Antipsychotic Agents
Asia; high dose; older patients; prescription patterns; schizophrenia