SUMMARY
Ryan T. Demmer, Ph.D., M.P.H., is a professor of epidemiology. His research focuses on clarifying causes and the correlation of chronic diseases including diabetes, atherosclerotic vascular disease, heart failure and dementia.
Dr. Demmer is particularly focused on understanding microbial causes of chronic conditions. In that context, he studies both chronic sequalae of infectious diseases as well as the emerging role of the human microbiome in the initiation and progression of cardiometabolic diseases. A microbiome is a community of microorganisms, such as bacteria, fungi, viruses and their genes, living together. Dr. Demmer researches the potential role of inflammatory phenotypes as biological mediators connecting microbes to preclinical and clinical problems.
Dr. Demmer participates in several collaborative projects on this general theme and is currently principal investigator of a National Institutes of Health-funded cohort study. This study is the Oral Infections Glucose Intolerance and Insulin Resistance Study (ORIGINS). The scientific aims of ORIGINS are to study the interplay between the subgingival microbiome and early risk for the development of type 2 diabetes.
Focus areas
- Does the human microbiome influence human health? With recent technological advances in genomic sequencing, scientists have the ability to explore the multiple ecosystems of bacteria, viruses and fungi living in and on the human body. The human microbiome has a genetic endowment about 100 times greater than the human genome. While some microbes might cause acute disease, such as influenza, E. coli and SARS-CoV-2, the majority of our microbiome is likely beneficial. Dr. Demmer and his colleagues suggest that microbes in the mouth and gut can help to produce nitric oxide, which is a molecule of great importance to human health.
- Do classical infections cause chronic diseases such as diabetes, heart attacks and Alzheimer's disease? It has long been known that certain infections can lead to chronic health problems. For example, strep throat can lead to kidney complications, rheumatic heart disease and SARS-CoV-2. SARS-CoV-2 is the virus that causes COVID-19. COVID-19 can impact the neurological system, causing loss of taste and smell for many months following the initial infection. Dr. Demmer explores a wide array of severe infections to better understand the long-term outcomes. He is interested in determining if periodontal infections in the mouth might contribute to extra-oral chronic diseases.
- How do microbes cause chronic diseases, often far from the original infection? The exact mechanisms linking an acute infection today to a chronic diseases in the future, such as a heart attack or Alzheimer's disease 20 years later, are not well understood. Through better understanding of these mechanisms, Dr. Demmer strives to develop targeted prevention and treatment approaches.
Significance to patient care
Understanding if and how bacteria, viruses and fungi contribute to, or prevent, long-term chronic health problems will help to develop tailored prevention and treatment approaches for people.
Professional highlights
- Faculty member, Delta Omega, honorary society in public health, 2020.
- Fellow, The American Heart Association, 2016.
- Calderone Research Award, Columbia University, 2010.