Claudia Satizabal, PhD
BY FRAN KRITZ
"Populations worldwide are facing an obesity epidemic. These same populations are aging and will contribute to the growing prevalence of dementia and Alzheimer's disease," says Claudia Satizabal, PhD, 33, assistant professor of neurology at the Boston University School of Medicine, and winner of a $118,773 research grant from the Alzheimer's Association to study the link between obesity, brain aging, and Alzheimer's disease. The grant is awarded to underrepresented faculty in biomedical research such as Dr. Satizabal, a Hispanic woman studying prevention and risk factors for Alzheimer's disease. "It's imperative to understand how obesity increases the risk of dementia and Alzheimer's disease so we can develop health policies and promote treatment strategies to diminish the consequences of obesity in late life," she says.
In her home country of Colombia, Dr. Satizabal graduated with a degree in microbiology from Los Andes University in Bogota in 2005. She earned her PhD studying the relationship of inflammatory proteins with cerebrovascular and neurodegenerative MRI markers of abnormal brain aging at the Pierre and Marie Curie University in Paris.
Neurology Now recently spoke with Dr. Satizabal about her research and how the Alzheimer's Association award will enhance her work.
Can you describe your field of research?
I am an epidemiologist interested in the genetic and lifestyle risk factors associated with brain aging, cognitive decline, and Alzheimer's disease. Particularly, I am intrigued by how lifestyle choices in midlife can affect brain health in late life.
Why the recent interest in the link between obesity and dementia?
Interest in this field started in the early 2000s, when a few epidemiological studies related body mass index (BMI) and central obesity, excessive fat around the abdomen, to a higher risk of Alzheimer's disease. Since then a growing body of literature has revealed a more complex relationship between obesity and brain aging, suggesting that the period of life in which individuals are overweight or obese confers a different risk of dementia and Alzheimer's disease in late life.
Can you explain the "obesity paradox?"
Studies show that obesity in midlife is a risk factor for dementia. However, if you look at people a few years before they are diagnosed, those who develop Alzheimer's disease tend to lose weight progressively about four to six years before the first clinical symptoms of cognitive decline and dementia We need to look at when people are obese and how that relates to the development of Alzheimer's disease.
What other factors are you considering?
Most studies have used simple measures of obesity, but perhaps we need to start looking at more specific markers. Cardiovascular research suggests that fat stored in specific locations in the body (visceral or subcutaneous fat, for example) confer differential metabolic risks. These may be more powerful predictors of disease than global obesity measures. We also still don't understand the biological mechanisms for why obesity in midlife is a risk factor for dementia in late life. It may help to study different biomarkers measured in blood, such as molecules secreted by adipose tissue and the types of fats in our diet, and their effect on brain health. We can also go a step further and study the potential gene-environment interactions contributing to a higher risk of dementia and Alzheimer's disease.
What has your recent research revealed about dementia?
My colleagues and I published a study February 2016 in the New England Journal of Medicine showing that the incidence of dementia at any age has declined over the past three decades. We've also seen a decline in vascular risk factors—lower rates of smoking and high blood pressure, among others—which could have contributed to the decline. But we also observed increasing rates of obesity and diabetes, which could counter the observed beneficial trends in dementia occurrence.
How will the award allow you to expand your research?
It allows me and my colleagues to continue to explore the link between obesity, aging, and Alzheimer's disease. Currently, we're looking at the Framingham Heart Study, one of the oldest and most notable epidemiological studies worldwide. Initiated in 1948, it includes three generations of participants who are followed periodically (every two or four years) to collect multiple health-related information over time. It offers a unique opportunity to study midlife lifestyle factors and risk of dementia in late life.
What other research are you conducting?
I'm also studying genetic determinants of brain aging and Alzheimer's disease. I'm actively involved in the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium, where I work with other researchers around the world. As part of the Neurology and Cognition working groups, I lead projects investigating the genetic determinants of the size of certain brain structures, as well as other projects studying the genetics of fine motor speed and visual memory.
What does this award mean to you?
As a young investigator, I am very grateful for the support of the Alzheimer's Association. This grant will certainly help me on my path to becoming an independent investigator in the field. The award is also special because it recognizes the work of underrepresented minorities in Alzheimer's disease research. I believe it is important to provide equal opportunities to scientists of diverse backgrounds because diversity enriches all fields of research, encourages the exchange of novel ideas, and increases awareness of the most vulnerable populations when formulating research questions.