Summary: In a nationwide Finnish study, people with Alzheimer’s disease who used antipsychotic medications had a 29% higher risk of head injury and a 22% higher risk of traumatic brain injury (TBI) compared with matched patients who did not use these drugs.
Source: Wiley
Key finding: Use of antipsychotic medications was associated with a statistically significant increase in the risk of head injuries and TBIs among community-dwelling persons diagnosed with Alzheimer’s disease. The results appear in the Journal of the American Geriatrics Society.
A nationwide register-based cohort in Finland examined outcomes for people with clinically verified Alzheimer’s disease diagnosed between 2005 and 2011. The study compared 21,795 individuals who initiated antipsychotic treatment with 21,795 matched nonusers (matched by age, sex, and time since Alzheimer’s diagnosis). Persons with prior head injury or a history of schizophrenia were excluded to isolate the association between antipsychotic exposure and subsequent head injury risk.
The investigators measured incident head injuries (ICD‑10 S00–S09) and traumatic brain injuries (ICD‑10 S06.0–S06.9) that resulted in hospitalization or death, using national hospital discharge and causes of death registers. Using inverse probability of treatment (IPT) weighted Cox proportional hazards models to adjust for confounding, antipsychotic use was linked to higher event rates and increased hazard ratios for both outcomes.
Event rates reported in the study were 1.65 versus 1.26 head injuries per 100 person‑years for users versus nonusers, and 0.90 versus 0.72 TBIs per 100 person‑years for users versus nonusers. The IPT‑weighted hazard ratios were 1.29 (95% CI 1.14–1.47) for head injuries and 1.22 (95% CI 1.03–1.45) for TBIs, indicating a meaningful elevation in relative risk associated with antipsychotic exposure in this population.
When specific antipsychotic agents were compared, quetiapine use was associated with a higher relative risk of TBI compared with risperidone (IPT‑weighted HR = 1.60; 95% CI 1.15–2.22). The authors note that this comparative finding between quetiapine and risperidone requires confirmation in further studies.
Lead author Vesa Tapiainen, MD, of the University of Eastern Finland emphasized the clinical implications: “Persons with Alzheimer’s disease already face an elevated risk of falls, head injuries, and worse outcomes after such events. Where possible, antipsychotic treatment should be limited to patients with the most severe neuropsychiatric symptoms, and only when nonpharmacological options are insufficient.”
Source:
Wiley
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Penny Smith – Wiley
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Original research:
“The Risk of Head Injuries Associated With Antipsychotic Use Among Persons With Alzheimer’s Disease.” Vesa Tapiainen MD; Piia Lavikainen PhD; Marjaana Koponen PhD; Heidi Taipale PhD; Antti Tanskanen PhD; Jari Tiihonen MD, PhD; Sirpa Hartikainen MD, PhD; Anna‑Maija Tolppanen PhD. Journal of the American Geriatrics Society. DOI: 10.1111/jgs.16275. (Closed access.)
Abstract
The Risk of Head Injuries Associated With Antipsychotic Use Among Persons With Alzheimer’s Disease
Background and objectives:
Antipsychotic medications are known to increase fall risk in older adults, but evidence on head injuries specifically is limited. This study investigated whether antipsychotic use is associated with a higher incidence of head injuries and traumatic brain injuries among community-dwelling people with Alzheimer’s disease.
Design:
Nationwide register‑based cohort study (MEDALZ cohort, Finland).
Setting:
The MEDALZ cohort includes Finnish community dwellers with clinically verified Alzheimer’s disease diagnosed between 2005 and 2011.
Participants:
The analysis included 21,795 incident antipsychotic users matched to 21,795 nonusers by age, sex, and time since AD diagnosis. Individuals with prior head injury or schizophrenia were excluded.
Measurements:
Outcomes were incident head injuries (ICD‑10 S00–S09) and TBIs (ICD‑10 S06.0–S06.9) leading to hospital admission or death. The study used inverse probability weighting and Cox models to estimate adjusted relative risks.
Results:
Antipsychotic users experienced higher event rates and an increased adjusted risk for head injuries and TBIs compared with matched nonusers. The IPT‑weighted hazard ratio for head injuries was 1.29 (95% CI 1.14–1.47) and for TBIs 1.22 (95% CI 1.03–1.45). Quetiapine users showed a higher adjusted risk of TBI compared with risperidone users (IPT‑weighted HR 1.60, 95% CI 1.15–2.22).
Conclusions:
In addition to known adverse events associated with antipsychotics, their use in persons with Alzheimer’s disease may increase the risk of head injuries and TBIs. Clinicians should restrict antipsychotic prescribing to patients with severe neuropsychiatric symptoms and consider nonpharmacological approaches when feasible. Comparative risk differences, such as the higher TBI risk observed with quetiapine versus risperidone, should be confirmed by further research.