Q&A with José Aravena ’25 PhD

Shortly after completing his master’s degree at the University of Chile, José Aravena ’25 PhD (Public Health) attended a lecture that changed the trajectory of his career. The presenter shared findings from a study by Yale Professor Becca Levy, which showed that people with more positive views of their own aging had a lower risk of developing Alzheimer’s disease—even among those with greater genetic risk. Fascinated by the idea of gene-environment interactions, he decided to pursue PhD studies at Yale.

In December, his dissertation was among the 40 awarded distinction, an honor given when all readers unanimously recognize the work as outstanding scholarship. The Graduate School conferred 197 PhD degrees in December. 

We sat down with Aravena to discuss how he first became interested in aging and brain health and to learn more about his findings from his fieldwork in southern Chile.
 

Tell me more about your research and key findings.

My main research topic is about dementia—Alzheimer’s disease (AD) and other dementias—and risk reduction and prevention from a public health standpoint. I tried to search for relationships between social determinants of health and public health interventions that can reduce dementia risk, with a focus on populations more exposed to social determinants of health, such as certain minority groups, Indigenous people, or people living in low‑income places, especially in Latin America. That’s my intersection point: how social determinants of health can be used as a way of preventing dementia, and how much of the risk of dementia or Alzheimer’s disease can be reduced if we address these social determinants of health.
 
One line of my research studies how genes that increase Alzheimer’s risk interact with social environments to determine dementia risk. In two of the studies I conducted during my PhD, we found that the expression of risk‑reducing and risk‑increasing genes depends a lot on your social position. When people have a greater social advantage, you can see the difference between those who have a greater genetic risk and a lower genetic risk—genes have more room to flourish in terms of phenotypical expression.
 
But when you go down the social ladder, the people more exposed to social determinants of health or who are socially disadvantaged, there are few differences in the risk of Alzheimer’s disease and dementias, regardless of the genetic risk. So, those with low genetic risk and those with high genetic risk have the exact same risk to develop dementia. And within this group (socially disadvantaged), they have the greatest risk overall compared to people at greater social advantage.
 
So, someone who is at high genetic risk but living at social advantage can have a lower dementia risk than someone who is genetically at low risk but living at social disadvantage. This suggests that environments shape the way our brains age and the phenotypical expression of certain genes. Genes will not always behave in the same way—a gene might be more deterministic in certain environments, but in other environments, it’s the environment that has more power over your health than your genes.
 

How did you first become interested in this topic?

One study by my mentor fascinated me and led me to think about gene–environment interactions. Shortly after completing my master’s degree in Chile, I attended a lecture where the presenter showed a study that assessed positive views about aging, dividing people by whether they held positive or negative views and by genetic risk. They found that people with more positive views of their own aging had a lower risk of developing Alzheimer’s disease—even among those with greater genetic risk. I was fascinated by the idea that an environment can be so potent that it can modify the way that a genetic marker for AD can express. I thought, that's definitely what I want to do, something that's multidisciplinary, combining medical science, social science, and genetics. So that was my entry point to my PhD studies with (Yale) Professor Becca Levy, which led to a wonderful collaboration, my going to the U.S. to study, and digging deeper into this research.
 
Before that, I was always interested in brain health. I worked for several years as an occupational therapist with families of people with dementia, and I saw how hard it was for families to cope, both emotionally and economically. That experience made me think about prevention: how could we arrive earlier, delay onset, and find ways to prevent Alzheimer’s disease? I became interested in policies that could mitigate social determinants of health with the goal of reversing or at least delaying cognitive symptoms.
 

Your research subjects included both Indigenous and non-Indigenous communities in Chile. Were there cultural differences that impacted your findings?

Yes, that’s another layer of my research: how our beliefs about the causes of dementia influence prevention behaviors and, therefore of our risk of developing dementia. We contrasted Indigenous and non‑Indigenous people living in the same regions and conducted a mixed‑methods study with extensive fieldwork and interviews to understand their views on dementia, from a cultural perspective. We found that people who believe dementia comes from within themselves (their health or behaviors) tend to have fewer risk factors—they have more agency. Those who attribute it to external factors (discrimination, poverty) tend to have more risk factors.
 
Our most interesting finding was about trauma. We thought that the concept of trauma itself might exert a bigger impact on Indigenous people because of their history. And we found that more Indigenous respondents cited trauma as a cause, and only among Indigenous participants was trauma attribution associated with higher dementia risk; that association was not found among non‑Indigenous participants. Our hypothesis is that groups that have been historically exposed to trauma, because of colonization or forced rural migration, are more likely to exhibit behaviors associated with both trauma and dementia risk, like smoking, alcohol intake, or poor cardiovascular care.
 

Did you come up with a set of recommendations from your findings?

Yes. Across the studies on structural factors, we argue that policy actions targeting structural inequalities, including disparities in healthcare access and older adult–provider interactions, can substantially reduce dementia risk at the population level. For the study with Indigenous people, we developed an interactive guide for Alzheimer’s prevention from the Indigenous Mapuche perspective. Community members had emphasized that researchers often don’t report back, so we wanted to share our results in the most understandable way possible. We aligned evidence‑based recommendations with cultural activities. For example, instead of saying ‘moderate physical activity 3x/week,’ we suggested walking around the lake three times per week. We also recommended trauma‑healing opportunities, such as encouraging people to share how they’re feeling, as a way of protecting their brain.
 

What’s one thing you wish that more people knew about your field of study?


That dementia and Alzheimer’s disease are not normal parts of aging. There are a lot of things you can do to prevent or delay symptoms—even in your late 70s or 80s. Brain health starts early and it’s always a good time to care for it.
 
More than half of healthcare providers still think dementia is a normal part of aging, which is terrible. We also need more advocacy around brain health; cancer and heart health often get more attention, and people tend to have a pessimistic view—seeing dementia as random or genetic—rather than recognizing the many controllable factors that reduce risk, even with genetic predisposition.
 

What are your career plans?

I’m now an assistant professor at the University of Chile on the tenure track, continuing my research on social determinants of health and dementia prevention and teaching graduate students. Most of my time is dedicated to research, with one class per semester. I really enjoy doing research—especially fieldwork—and hope to continue along this path.