Variations in the use of antidementia and antipsychotic drugs for nursing home residents with dementia across the United States suggest a need for better guidance for health care practitioners, patients and families, according to a study published by UMass Chan Medical School researchers.

The study, led by Matthew Alcusky, Ph.D., PharmD, associate professor of population & quantitative health sciences, appeared in the journal Medical Care.

Using federal 2018 Minimum Data Set 3.0 linked to Medicare data, facility information and Dartmouth Atlas files, the researchers found that overall, 20.9% of nursing home residents used antipsychotics; 16.1% used the antidementia drug memantine; and 23.3% used cholinesterase inhibitors, another antidementia drug.

Nursing homes in geographic regions with the highest health care utilization in general had greater antidementia drug use. But resident or facility factors were associated with more antipsychotic use. The variations raised questions for investigators.

“When the evidence base is not clear, that’s where we start to see variations, where other factors are taking over such as physician preference,” said senior author Kate Lapane, Ph.D., professor of population & quantitative health sciences. “We start to explore what it is about the context that is driving the differences. So, in the area of people with dementia living in nursing homes, it’s ripe for that kind of investigation, because clinicians don’t agree.”

Dr. Alcusky, who trained as a pharmacist and studies pharmacoepidemiology, pharmacoeconomics and health policy research, said, “I generally try to prioritize focusing on disease states and research questions where I can make a meaningful impact on a large number of individuals. About 50% of nursing home residents have Alzheimer’s disease or another dementia and there’s really a need for further research and therapeutic options.”

Alcusky said the drugs available to treat Alzheimer’s in this study were only modestly clinically effective and carry some side effects. Also, a lot of the evidence that contributed to their FDA approval was based on use among people living in the community, who were younger.

“So, there’s really a gap of understanding how they’re being used in nursing homes and to what effect,” he said. “We suspected that there was going to be a lot of variation that was borne out in this study because of conflicting recommendations or lacking recommendations from consensus guidelines.”

Antipsychotics, drugs that carry an FDA black box warning because of increased mortality and cerebrovascular events in older adults, were still used by one in five residents in the study. Researchers didn’t investigate the appropriateness of the use of drugs, but they found it was driven by characteristics of the facilities and residents.

“The facilities that were ranked poor on staffing quality and the facilities that had evidence of using physical restraints were associated with higher prevalence of antipsychotics,” said Dr. Lapane.

“Whereas with antidementia drugs, the higher prevalence was associated with higher health care utilization in the area, and perhaps a reflection of what residents were receiving in the community that carried into the nursing home. So, there were different phenomenon driving each class of drugs, which was interesting.”

Alcusky said he hoped the paper might inform what underlies the variations in drug use and lead to development of clearer guidelines and better decision making for residents, their families and care teams.