Kuopio, Finland—A new study underscores why pharmacists might want to dispense antipsychotics to Alzheimer’s disease patients with a word of caution to patients and caregivers.

The report in the Journal of the American Geriatrics Society warns that use of antipsychotics is associated with increased risks of head and brain injuries among Alzheimer’s patients. University of Eastern Finland–led researchers add that the risk increase was highest at the initiation of use of the drugs.

“As adverse effects, antipsychotics may cause sedation, orthostatic hypotension, and arrhythmias which all may lead to falls. Among older persons, falls are the most common reason for traumatic brain injuries,” explained lead author Vesa Tapiainen, MD.

Researchers used a nationwide register-based cohort study to better understand the association of antipsychotic use and risk of head injuries among community dwellers with AD.

The Medication Use and Alzheimer’s Disease (MEDALZ) cohort includes Finnish community dwellers who received clinically verified AD diagnosis in 2005 to 2011. The study team identified incident antipsychotic users from the Prescription Register and matched them with nonusers by age, sex, and time since AD diagnosis, resulting in 21,795 matched pairs. Excluded were those with prior head injury or history of schizophrenia.

Defined outcomes were incident head injuries and traumatic brain injuries (TBIs).

Results indicated that antipsychotic use was associated with an increased risk of head injuries (event rate per 100 person-years = 1.65; [95% CI, 1.50-1.81] for users and 1.26 [95% CI, 1.16-1.37] for nonusers; inverse probability of treatment (IPT)-weighted hazard ratio [HR] = 1.29; [95% CI, 1.14-1.47]) and TBIs (event rate per 100 person-years = 0.90; [95% CI, 0.79-1.02] for users and 0.72 [95% CI, 0.65-0.81] for nonusers; IPT-weighted HR = 1.22 [95% CI, 1.03-1.45]).

The authors point out that quetiapine users had higher risk of TBIs (IPT-weighted HR = 1.60 [95% CI, 1.15-2.22]) in comparison with risperidone users.

“These findings imply that in addition to previously reported adverse events and effects, antipsychotic use may increase the risk of head injuries and TBIs in persons with AD,” researchers conclude. “Therefore, their use should be restricted to most severe neuropsychiatric symptoms, as recommended by the AGS Beers Criteria. Additionally, higher relative risk of TBIs in quetiapine users compared to risperidone users should be confirmed in further studies.”

Background information in the articles notes that antipsychotics are commonly used to treat neuropsychiatric symptoms of Alzheimer’s disease. According to clinical-care guidelines, treating the cause of these symptoms, such as pain, is the first-line option, and secondly, nonpharmacological treatments should be prioritized.

The authors emphasized that use of antipsychotics should be restricted to the most severe symptoms, such as severe aggression, agitation, or psychosis.

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