Patients with Alzheimer's who use antipsychotics at increased risk for head injury, TBI

Patients with Alzheimer’s disease who use antipsychotic medications may be at an increased risk for head injuries and traumatic brain injuries, or TBIs, according to findings of a nationwide register-based cohort study conducted in Finland and published in Journal of the American Geriatrics Society.

“Persons with Alzheimer’s disease have a higher risk of falling, head injuries and [TBIs] and worse prognosis after these events in comparison to those without Alzheimer’s disease,” Vesa Tapiainen, MD, of the University of Eastern Finland’s School of Pharmacy, said in a press release. “Therefore, it is important to avoid further increase risk with antipsychotics in this vulnerable population, if possible.”

Data from a recent meta-analysis revealed that antipsychotic use was associated with 54% higher odds of falls among older individuals, Tapiainen and colleagues noted. Further, patients with Alzheimer’s disease and other forms of cognitive disorders have been found to experience rates of injurious falls, such as hip fractures, while on antipsychotics. However, the present study is the first that, to the knowledge of the researchers, assessed the association of antipsychotic use with head injuries and TBIs.

To do so, they analyzed data from Finnish community dwellers included in the Medication Use and Alzheimer’s Disease cohort, which comprises individuals who received an incident Alzheimer’s disease diagnosis between 2005 and 2011. The researchers then identified incident antipsychotic users from the Prescription Register and matched them with nonusers by age, sex and time since diagnosis, for a total of 21,795 matched pairs. They excluded individuals with prior head injury or history of schizophrenia.

Tapiainen and colleagues found that antipsychotic users had an increased risk for head injuries according to event rate per 100 person-years of 1.65 (95% CI, 1.5-1.81) vs. 1.26 (95% CI, 1.16-1.37) for nonusers. For TBIs, the event rate was 0.9 (95% CI, 0.79-1.02) for users and 0.72 for nonusers (95% CI, 0.65-0.81). Patients using quetiapine had higher risk for TBIs (HR = 1.6; 95% CI, 1.15-2.22) compared with risperidone users.

“Increased risk should be accounted for especially at the initiation of antipsychotic use, as the risk for head injuries and TBIs was higher at the initiation,” the researchers wrote. – by Joe Gramigna

Disclosures: Tapiainen reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.