Changes in the trend of anti-psychotics prescription in elderly patients in a general hospital in Singapore 2005–2013

Abstract

Objectives

This was a descriptive study of the prescription trend of anti-psychotics for elderly patients in a general hospital in Singapore.

Methods

Elderly patients aged >65 who received at least 1 prescription of anti-psychotics during 2005, 2007, 2009, 2011 and 2013 in Tan Tock Seng Hospital, Singapore, were selected. Data was obtained from the hospital computerized prescription records.

Results

The total number of elderly patients who received anti-psychotics increased from 865 in 2005 to 1990 in 2013. Following the official warning issued by the health sciences authority in 2004 regarding the increased risks of cerebrovascular events in elderly patients taking olanzapine and risperidone, prescriptions for risperidone reduced between 2005 to 2013 (20.74% vs. 11.79%, 95% CI: 0.07–0.10, P < 0.0001). However, the percentage of prescriptions of other atypical anti-psychotics such as quetiapine increased from 27.47% to 58.48% (95% CI: 0.29–0.33, P < 0.0001), in 2005 and 2013 respectively, and prescriptions for olanzapine remained relatively stable at 6.65% in 2005 and 8.94% in 2013 (P > 0.05). With the black box warnings extended to typical anti-psychotics 3 years later, the percentage of prescriptions of typical anti-psychotics decreased between 2005 to 2013, e.g. haloperidol (33.19% vs. 13.39%, 95% CI: 0.17–0.22; P < 0.0001), sulpiride (6.58% vs. 2.83%, 95% CI: 0.03–0.05, P < 0.0001) and chlorpromazine (3.85% vs. 1.85%, 95% CI: 0.01–0.03, P < 0.0001).

Conclusions

After the first safety warning the percentage of prescriptions for risperidone dropped significantly, and there was a significant increase for quetiapine. The percentage of haloperidol, sulpiride and chlorpromazine prescriptions declined after both warnings. Anti-psychotics use in the elderly continues to be prevalent.

Disclosure of interest

The authors have not supplied their declaration of competing interest.