Contributed by Joshua Grill, PhD, Director of UCI MIND
In a new study, colleagues at the Alzheimer’s Disease Research Center at Washington University have found that levels of the cerebrospinal fluid protein tau, one of the hallmark pathologies in Alzheimer’s disease (AD), is lower in African Americans compared to Whites. This was true both for older participants who did and did not have memory problems. The study is not the first to find such differences between African Americans and Caucasians and it has important implications to a number of important areas of AD research.
First, there is a growing movement to categorize AD based primarily on biology through tests such as protein levels in the cerebrospinal fluid or brain scans that pick up changes associated with the disease. A critical aspect of this effort, however, is to set specific criteria that distinguish AD from “normal.” This study suggests that setting these thresholds may not be easy, especially if they are different in people of different racial or ethnic backgrounds.
Another important criticism of the push to emphasize biology in AD diagnosis is that the overwhelming scientific evidence informing our understanding of these concepts come from studies in which the samples are comprised of all (or mostly all) Non-Hispanic White participants. There are no such data available from Hispanics, Asians, American Indian or Alaskan Natives, Native Hawaiian or other Pacific Islanders. Many more studies with samples that are representative of the diverse US population are needed before we can make widespread changes in clinical practice of diagnosing AD.
Lastly, the implications of these findings for development of new AD treatments are wholly unknown. If tau is higher in AD but lower in African Americans, will tau-lowering drugs work the same in African Americans with AD as they will in Whites? To address questions like this one, we will need to drastically diversify participation in clinical trials of promising disease-modifying therapies.
At UCI MIND, we’ve been trying to increase the diversity of research participants, with a particular emphasis on Chinese Americans. We need to embrace other groups, however, and Orange County’s diverse community creates an opportunity to do so. If you are interested in participating in research, please consider enrolling in the UCI Consent-to-Contact Registry.