a1 Faculty of Pharmacy, The University of Sydney, New South Wales, Australia
a2 Clinical Pharmacology and Geriatric Pharmacotherapy Unit, School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
a3 Kuopio Research Centre of Geriatric Care, University of Eastern Finland, Kuopio, Finland
a4 Leppävirta Health Centre, Leppävirta, Finland
a5 Quality Use of Medicines and Pharmacy Research Centre, Sansom Institute, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia
Background: Antipsychotics are associated with adverse events and mortality among older adults with dementia. The objective of this study was to evaluate the risk of death associated with antipsychotic use among community-dwelling older adults with a range of comorbidities.
Methods: This was a population-based cohort study of all 2,224 residents of Leppävirta, Finland, aged ≥65 years on 1 January 2000. Records of all reimbursed drug purchases were extracted from the Finnish National Prescription Register and diagnostic data were obtained from the Special Reimbursement Register. All-cause mortality was evaluated over a nine-year follow-up period. Time-dependent Cox proportional hazard models were used to compute unadjusted and adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of mortality of antipsychotic use compared to non-use.
Results: In total, 332 residents used antipsychotics between 2000 and 2008. The unadjusted HR for risk of death associated with antipsychotic use was 2.71 (95% CI = 2.3–3.2). After adjusting for baseline age, sex, antidepressant use, and diagnostic confounders, the HR was 2.07 (95% CI = 1.73–2.47). The adjusted HR was the highest among antipsychotic users with baseline respiratory disease (HR = 2.21, 95% CI = 1.30–3.76).
Conclusions: The increased risk of death associated with antipsychotic use was similar across diagnostic categories, the highest being among those with baseline respiratory disease. However, the results should be interpreted with caution, as the overall sample size of antipsychotic users was small. As in other observational studies, residual confounding may account for the higher mortality observed among antipsychotic users. Further research is needed to confirm these findings.
(Received September 08 2011)
(Revised October 14 2011)
(Revised January 13 2012)
(Accepted January 15 2012)
(Online publication February 27 2012)
c1 Correspondence should be addressed to: Natasa Gisev, Faculty of Pharmacy, Pharmacy and Bank Building (A15), The University of Sydney, New South Wales, Australia 2006. Phone: +612 9036 7081; Fax: +612 9351 3491. Email: firstname.lastname@example.org.