The health inequities that have long plagued the U.S. were highlighted and worsened by the Covid-19 pandemic. Low-income and minoritized populations, such as Black and Hispanic Americans, are not only at greater risk of infection, hospitalization, and death from the disease, but they are also up to twice as likely to develop chronic diseases like cancer, diabetes, heart disease, and Alzheimer’s disease.
The roots of these disparities are deep and complex. But one of them that bears highlighting is the extent to which regulatory approval pathways affect how medical research is conducted in the U.S.
For decades, clinical trial protocols for new treatments have been shaped by the regulatory gantlet that innovations must travel to win approval by the Food and Drug Administration (FDA). But the FDA’s clinical trial roadmap, long held up as the gold standard for medical research, leads to procedures that have inherent structural barriers to participation, such as needing to take time off from work or travel to a trial site. These requirements often lead to trials that fail to represent broad swaths of the U.S. population, and result in imprecise diagnoses or improper treatment guidelines for those largely excluded from these studies. That translates into poorer health outcomes among minoritized populations and deeper, more persistent health inequities despite best intentions to address these imbalances.
In the U.S., people other than non-Hispanic whites make up less than 10% of participants in clinical trials, the essential vehicles for evaluating promising diagnostic tools, drug treatments and medical devices. This lack of diversity has real world consequences.
Symptom profiles for disease risk are not uniform across racial and ethnic groups, and different people react to medications in different ways. With fewer people of color represented in clinical trials, researchers have little information on how new medications work in non-white populations, less understanding of how to fight diseases that impact this growing group, and fewer insights into how to create better therapies. With the move toward precision medicine fueled by genetic factors, the lack of inclusion is leading to biased treatment success. One result: higher rates of disease and death among people of color compared to non-Hispanic white Americans.
It is time to put health equity at the center of medical research. A foundational goal of providing better health for all means starting with the problem and working backward to design an approach to medical research and testing that maximizes inclusion and minimizes exclusion.
The Davos Alzheimer’s Collaborative, an organization funded by philanthropy, pharmaceutical companies, private companies, and others, offers one example of how to combat the problem of representation.
Nearly all genetic analyses of Alzheimer’s disease has been conducted on white people of Western European origin, ignoring 90% of the world’s population.
To bring greater diversity into an understanding of Alzheimer’s disease, the Davos Alzheimer’s Collaborative has launched a global research initiative, which I help lead. We are working to build a global cohort that will ideally number more than one million people, and are starting with people from 26 countries, including those from Latin America, Africa, and Asia, living in countries often not included in international medical research consortia efforts.
In making inclusiveness the priority, my colleagues and I have been fundamentally rethinking the data we collect, where we collect it, and how we analyze it. This work — and other research I hope it inspires — will build a better understanding of a complex disease in all its heterogeneity. And it will accelerate the discovery of new treatments that can be targeted to meet precision objectives for everyone and help end, or at least minimize, health inequities.
There is strong historical precedent for this approach. In 1948, the National Institutes of Health commissioned what became known as the Framingham Heart Study. This large, observational trial — which has come to involve more than 15,000 people over the years — represents perhaps the longest, most in-depth research effort in medical history. In its earliest years, it delivered discoveries that essentially laid the foundation for the field of preventive medicine.
Before the Framingham study began, scientists had little understanding that high blood pressure and high cholesterol contributed to the risk of heart attack and stroke. The knowledge gained helped lead to extraordinary scientific discoveries and the development of a vast array of effective treatments that have saved many millions of lives.
In 1948, white people made up nearly 90% of the U.S. population. Today, non-white people make up 42% of the population, highlighting the need to conduct Alzheimer’s research in a more diverse population. Doing so will give scientists better chances of identifying new markers that predict the disease earlier and developing targeted new approaches for treating everyone, not just some. This encompassing approach will also help establish new gold standards that reduce persistent health inequities, end glaring disparities in treatment, and deliver on the promise of making the extraordinary advances in modern medicine available to all.
Given the comprehensiveness and richness of the Davos cohorts, we aim to do for the brain what the Framingham study has done for the heart.
Rhoda Au is a professor of anatomy and neurobiology at Boston University School of Medicine, a senior investigator with the Framingham Heart Study, and director of the Davos Alzheimer’s Collaborative’s Global Cohorts Program.