Antipsychotics up risk of head injuries, TBIs in elderly AD patients

The use of antipsychotics may increase the risk of head injuries and traumatic brain injuries (TBIs) among elderly adults with Alzheimer’s disease (AD), a recent Finland study has found.

Researchers conducted a nationwide, register-based cohort study including 21,795 AD patients (66.3 percent female) who initiated the use of antipsychotics after diagnosis, and 21,795 matched nonuser controls (66.3 percent female). Head injuries and TBIs resulting in hospitalization or death were the study outcomes.

Over a median follow-up of 253 days, antipsychotic medication users experienced a cumulative of 595 head injuries. Risperidone (62.2 percent) and quetiapine (30.1 percent) were the most common agents taken. Nonusers were followed-up for a longer time (median, 748 days), during which a total of 422 head injuries were sustained.

The difference in head injury incidence rate was significantly greater in those who took antipsychotics (adjusted hazard ratio [HR], 1.29, 95 percent confidence interval [CI], 1.14–1.47).

TBIs followed the same pattern. Over 25,610 person-years of follow-up, 230 incident cases of TBIs occurred in the antipsychotic group. This was significantly greater than the 342 cases in nonusers, detected over 47,193 person-years of follow-up (adjusted HR, 1.23, 95 percent CI, 1.03–1.46).

Comparing between the most common agents, researchers also found that quetiapine had a stronger effect on the incidence of head injuries than risperidone (adjusted HR, 1.27, 95 percent CI, 0.99–1.62). The same was true for TBIs (adjusted HR, 1.59, 95 percent CI, 1.14–2.21).