Conventional and atypical antipsychotic drugs show differing safety risks among older nursing home residents
Research Activities, September 2012, No. 385
Up to a third of older nursing home residents are treated with antipsychotics to help control behavioral problems. In two studies supported by the Agency for Healthcare Research and Quality (HS17918, HS16097), the researchers found that atypical antipsychotic drugs (such as risperidone) were associated with lower hazard rates than conventional antipsychotic drugs (such as haloperidol) for overall death rates and rates of specific causes of death, excluding cancer. Similarly, they found that the risk of developing cardiac disease, hip fractures, and infections were lower for treatment with atypical rather than conventional antipsychotic drugs. However, risks of cerebrovascular events were lower for conventional antipsychotic drugs. In both studies, the researchers analyzed data on new users of antipsychotic drugs (haloperidol, aripiprazole, olanzapine, quetiapine, risperidone, and ziprasidone) among elderly adults, who were eligible for Medicaid and lived in a nursing home in 2001–2005. Both studies are briefly described here.
Huybrechts, K.F., Gerhard, T., Crystal, S., and others (2012). "Differential risk of death in older residents in nursing homes prescribed specific antipsychotic drugs: Population based cohort study." British Medical Journal 344:e977, 12 pp.
This study compared the risk of death in 75,445 elderly nursing home residents. The researchers found that users of haloperidol, a conventional antipsychotic drug, were twice as likely to die within 180 days of beginning treatment (107 percent increased risk) than residents treated with risperidone, an atypical antipsychotic. Only quetiapine (another atypical antipsychotic) exhibited significantly lower 180-day mortality (by 19 percent) than risperidone. The effect of haloperidol was strongest during the first 40 days of treatment, and declined during the rest of the 180-day period. The risperidone–quetiapine difference was also greatest during this initial period. Dose effects were the strongest for haloperidol, with mortality risk 84 percent greater for high-dose than low-dose therapy. Similarly, risperidone risk was 35 percent greater for high-dose than low-dose therapy.
Huybrechts, K.F., Schneeweiss, S., Gerhard, T., and others (2012, March). "Comparative safety of antipsychotic medications in nursing home residents." Journal of the American Geriatrics Society 60(3) pp. 420-429.
This study examined how the antipsychotic drugs differed in risk of developing major medical events—serious bacterial infection, heart attack, cerebrovascular event (stroke or transient ischemic attack), or hip fracture. Of the 83,959 nursing home residents included in the group, 8.9 percent were prescribed a conventional antipsychotic drug and 91.1 percent were prescribed an atypical antipsychotic. Based on hospitalizations for the major medical events within 180 days of starting antipsychotic therapy, residents who began taking a conventional antipsychotic (haloperidol) were at 37 percent greater risk of developing a serious bacterial infection, but had 19 percent lower risk of a cerebrovascular event than were residents who initiated taking an atypical antipsychotic (risperidone). Residents taking a conventional antipsychotic were at greater risk of heart attack (by 23 percent), hip fracture (by 27 percent), and pneumonia (by 28 percent), but these increases were not statistically significant. Both the increased risk of serious bacterial infection and the decreased risk of cerebrovascular events for nursing home residents taking haloperidol were dose-dependent. Comparison of other atypical antipsychotic drugs with risperidone found only modest significant differences for cerebrovascular event risk for residents who began taking olanzapine or quetiapine, but a significantly reduced risk of serious bacterial infections (by 17 percent) for those starting quetiapine.