March 24, 2016

Antipsychotic medications are prescribed to Hispanics with Alzheimer’s disease or other dementias at higher rates than non-Hispanic whites, for dementia-related mental-health symptoms such as depression, anxiety and aggression, a UC Davis study conducted using data from a large and diverse population of elderly dementia patients has found.

While the overall use of antipsychotic medications was approximately 10 percent among non-Hispanic whites with dementia, it was more than 15 percent, or 50 percent greater, among Hispanic patients with dementia.

Antipsychotic medications are used to treat neuropsychiatric disorders such as delusions, hallucinations, agitation or aggression, depression or dysphoria, anxiety and irritability, among other symptoms. Their use carries a “black box warning” — the highest possible by the U.S. Food and Drug Administration — because of concerns over the risks of worsening patient quality of life and increased mortality.

The research is reported in the Journal of Neuropsychiatry and Clinical Neurosciences.

“Although we are familiar with ethnic and or racial variations in medication usage, we were surprised to find that Hispanic patients with dementia use antipsychotics more often than non-Hispanic whites and African-Americans in this large national cohort,” said study senior author Glen Xiong, UC Davis associate professor of psychiatry and behavioral sciences.

The study of the use of medications for dementia-related neuropsychiatric symptoms was conducted using data from the 34 federally funded Alzheimer’s Disease Centers in the United States and aggregated by the National Alzheimer’s Coordinating Center, a program funded by the National Institute on Aging (NIA), one of which is located at UC Davis and directed by Professor of Neurology Charles DeCarli.

The research included more than 9,000 individuals with Alzheimer’s disease or dementia who were either non-Hispanic white, Hispanic or African-American. The use of antipsychotic medications was relatively common, with about 10 percent, or 930, reportedly taking one or more antipsychotic medications. Sixty-two percent of the individuals prescribed antipsychotic medications were Hispanics.

Xiong said that it is unclear why elderly Hispanics with dementia are prescribed more antipsychotic medications. Neither the severity of the patient's dementia nor their psychiatric symptoms would account for the differences. However, the Sacramento-Area Latino Study on Aging previously has found that Hispanic families often are more likely to care for more impaired elderly family members than other populations.

“The reasons behind the study outcomes seem highly complex, and definitely warrant further investigation before we can come up with any rational explanations and interventions,” Xiong said.

Future research should examine how long individuals are taking antipsychotic medications and other factors, Xiong said, such as whether clinicians are prescribing antipsychotic medications to Hispanic patients based on their clinical profiles versus reports from caregivers, and whether these patients are experiencing more agitation and hallucinations and are thus prescribed more of the drugs. 

Other study authors are Teresa Filshtein, Laurel A. Beckett and W. Ladson Hinton, all of UC Davis.

The research was supported by the UC Davis Alzheimer’s Disease Center, which is funded by National Institute on Aging grants AG-10129 and AG-01961, the Center for Health Care Policy and Research and the UC Davis Clinical and Translational Science Center.   

The UC Davis Alzheimer's Disease Center is one of only 27 research centers designated by the National Institutes of Health's National Institute on Aging. The center's goal is to translate research advances into improved diagnosis and treatment for patients while focusing on the long-term goal of finding a way to prevent or cure Alzheimer's disease. Also funded by the state of California, the center allows researchers to study the effects of the disease on a uniquely diverse population. For more information, visit