Atypical antipsychotic drugs and risk of ischaemic stroke: population based retrospective cohort study.
OBJECTIVE
To compare the incidence of admissions to hospital for stroke among older adults with dementia receiving atypical or typical antipsychotics.


METHODS
Population based retrospective cohort study.


METHODS
Ontario, Canada. Patients 32,710 older adults (< or = 65 years) with dementia (17,845 dispensed an atypical antipsychotic and 14,865 dispensed a typical antipsychotic).


METHODS
Admission to hospital with the most responsible diagnosis (single most important condition responsible for the patient's admission) of ischaemic stroke. Observation of patients until they were either admitted to hospital with ischaemic stroke, stopped taking antipsychotics, died, or the study ended.


RESULTS
After adjustment for potential confounders, participants receiving atypical antipsychotics showed no significant increase in risk of ischaemic stroke compared with those receiving typical antipsychotics (adjusted hazard ratio 1.01, 95% confidence interval 0.81 to 1.26). This finding was consistent in a series of subgroup analyses, including ones of individual atypical antipsychotic drugs (risperidone, olanzapine, and quetiapine) and selected subpopulations of the main cohorts.


CONCLUSIONS
Older adults with dementia who take atypical antipsychotics have a similar risk of ischaemic stroke to those taking typical antipsychotics.
Gill
Sudeep S
SS
Institute for Clinical Evaluative Sciences, 2075 Bayview Avenue, Toronto, ON, Canada. gills@pccchealth.org
Rochon
Paula A
PA
Herrmann
Nathan
N
Lee
Philip E
PE
Sykora
Kathy
K
Gunraj
Nadia
N
Normand
Sharon-Lise T
SL
Gurwitz
Jerry H
JH
Marras
Connie
C
Wodchis
Walter P
WP
Mamdani
Muhammad
M
D000368:Aged; D014150:Antipsychotic Agents / Q000009:adverse effects*; D015331:Cohort Studies; D003704:Dementia / Q000188:drug therapy* / Q000453:epidemiology; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D009864:Ontario / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D020521:Stroke / Q000139:chemically induced*
D014150:Antipsychotic Agents