Older men with dementia at greater risk than women of serious events after initiating antipsychotic therapy

Objectives — The authors know little about sex differences in response to drug therapy among older women and men who use the most medications. Understanding how drug therapy differently affects older women and men is important to making informed prescribing decisions.

Design — Population-based, retrospective cohort study.

Setting — Ontario, Canada.

Participants — 21,526 older adults (13,760 women and 7,766 men) with dementia newly started on an oral atypical antipsychotic therapy between April 1, 2007 and March 1, 2010.

Measurements — Absolute numbers and rates of serious events. Serious events weredefined as a hospital admission or death within 30 days of treatment initiation. Unadjusted and adjusted odds ratios were compared between women and men in the full cohort and in strata based on setting of care, age, Charlson comorbidity scores, and antipsychotic dose.

Results — Among 21,526 older adults with a median age of 84 years, 1,889 (8.8%) hada serious event (1,044 [7.6%] women and 845 [10.9%] men). Of this group, 363 (2.6%) women and 355 (4.6%) men died. Relative to women, men were more likely to be hospitalized or die during the 30 day follow up period (adjusted odds ratio, 1.47; 95% CI, 1.33-1.62) and consistently more likely to experience a serious event in each stratum. A gradient of risk by drug dose was found for the development of a seriousevent in both women and men.

Conclusion — The risk of developing a serious event shortly after the initiation of antipsychotic therapy was high in women and men with dementia but was consistently higher in older men. This pattern remained the same in strata based on setting of care, age, CCI, and antipsychotic dose.