Rebecca S. Bahn, M.D.
Time to focus on research had 'tremendous impact'
Through Mayo Clinic's Clinician-Investigator Program, which combines clinical specialty or subspecialty training with two years of research experience, endocrinologist Rebecca S. Bahn, M.D., gained a distinct advantage — the time she needed to establish her research.
"The program gave me the opportunity to add research as part of my endocrine fellowship," she recalls. "In retrospect, it was a lot more important than I understood then. If I hadn't had that extra time at that point to develop my research, I might never have had the time."
Highlights followed: receiving National Institutes of Health (NIH) grants; exploring the link between autoimmune disease and thyroid disorders; gaining recognition as a leading authority on Graves' disease; being elected president of the American Thyroid Association; and achieving leadership roles at Mayo Clinic, where she heads the mentoring of young clinician-investigators and research into conditions that disproportionately affect women.
"The Clinician-Investigator Program had a tremendous impact on my career," Dr. Bahn says. "It got me started. It gave me a very solid foundation and direction and mentorship."
Today, Dr. Bahn is one of more than 40 clinical endocrinologists at Mayo Clinic in Rochester, Minn., ranked No. 1 for diabetes and endocrinology in U.S. News & World Report Best Hospitals. As a member of the Thyroid Clinical Service Group, she primarily treats patients with thyroid disorders, especially Graves' disease. Since 2001, Dr. Bahn has held the title of clinician-investigator, signifying that Mayo Clinic supplements her NIH research grants.
Like father, like daughter
The daughter of a pathologist who specialized in the pathology of endocrine diseases and researched their development at Mayo Clinic in Rochester, Dr. Bahn knew at a young age that she wanted to be an endocrinologist.
"Endocrine conditions are often best understood if one has knowledge of the physiology and biochemistry involved, and the treatment for those conditions stems directly from that understanding, so there's an innate logic tied to understanding and treating endocrine diseases," she says, explaining the interest she shared with her father.
Pursuing a master's degree in anatomy and conducting two years of research in endocrinology left her "quite certain that, besides caring for patients with endocrine diseases, I also wanted to have a significant component of research in my career."
Finding a topic to research
After Mayo Medical School, a residency in internal medicine and initial training in endocrinology, all at Mayo Clinic, she began her hometown Clinician-Investigator Program in immunology and endocrinology in 1985. While other institutions treat clinical training and research training as separate entities, Dr. Bahn appreciated that the Clinician-Investigator Program integrates them.
"As part of your fellowship, you begin to learn how to treat patients and see the deficiencies in available treatment," she says. "That helps you know what you should be studying in the lab and helps you move toward important topics and translational areas of research."
An interest in immunology led Dr. Bahn to focus on the thyroid, the gland most often targeted in a misguided attack by the immune system, then Graves' disease, an autoimmune disease that results in an overactive thyroid, and ultimately Graves' ophthalmopathy, associated eye changes characterized by protruding eyeballs.
"How an overactive thyroid relates to this eye disease is a classic endocrine conundrum," Dr. Bahn says. "And when you see patients with this serious disease that can impact their lives on multiple levels, yet the treatment options are still somewhat limited, you want to do something to help them."
Dr. Bahn learned the ins and outs of research under the mentorship of Mayo experts in endocrinology and immunology.
"The program allowed me, an endocrine fellow, to learn from Dr. Chella David, a world-renowned immunologist," she says. Just as important, the fellowship prepared her to apply for funding.
"It's a wonderful program that really helps investigators get the competitive edge, so they are much better prepared to apply for funding from NIH and other external sources," Dr. Bahn says. "The program gave me the basis to apply for" and receive two years of NIH funding as an NIH research trainee in immunology and endocrinology at Mayo Clinic and a first NIH R01 grant.
Dr. Bahn eventually discovered the connection between the eyes and the thyroid: a certain protein that acts as a receptor for thyroid-stimulating hormone (TSH). The same antibodies that target this receptor on thyroid cells, stimulating the cells to secrete too much thyroid hormone, also target receptors on fibroblasts behind the eye, causing them to turn into fat cells and produce a connective substance. The resulting tissue changes push the eyeball forward.
Now, in collaboration with a group at NIH, Dr. Bahn is working on a potential therapy for both Graves' disease and Graves' ophthalmopathy. In cell culture, she proved that a small-molecule inhibitor can prevent the TSH receptor from being stimulated by antibodies or TSH. If NIH toxicity studies in mice succeed, the TSH receptor inhibitor will advance to clinical trials.
Looking back, Dr. Bahn cherishes the head start given to her by the Clinician-Investigator Program: "Time to learn how to do research and to develop your research program, before you become deeply involved in your medical practice, is the biggest gift of all."