Dr. Katherine Hahn

Dr. Hahn views that continuity as the heart of medicine. She believes in demystifying diagnoses that can feel complicated or daunting, as well as helping patients understand what is happening in their bodies and what they can do about it. Her goal is to make patients feel informed, empowered, and confident in their care.

She treats a broad range of gastrointestinal conditions, including inflammatory bowel disease, esophageal disorders, and more. Her particular areas of expertise are women’s gastrointestinal health and liver disease. As a woman in a traditionally male-dominated speciality, she is particularly interested in the ways digestive health evolves throughout a woman’s life, including during pregnancy and perimenopause.

Her interest in medicine began early. As a teenager, she volunteered in the emergency room of her local hospital and quickly found herself drawn to both the science and human connection of medicine. She combined these interests through research at Cold Spring Harbor Laboratory, working in Dr. James Watson’s laboratory on investigating the neuromuscular junctions of fruit flies.

Dr. Hahn earned her Bachelor of Arts through Northwestern University’s prestigious Honors Program in Medical Education before attending Northwestern University Feinberg School of Medicine. After medical school, Dr. Hahn earned a Master of Public Health from the Johns Hopkins Bloomberg School of Public Health. She completed her residency in internal medicine at Georgetown University Hospital, where she was named Chief Resident. Dr. Hahn then completed her fellowship in gastroenterology and hepatology, also at Georgetown.

Gastroenterology felt like a natural convergence of her interests. She was drawn to the specialty’s anatomy and physiology, its emphasis on diagnostic reasoning, and the ability to intervene directly. During residency, her father-in-law required a liver transplant. Watching his care unfold changed her understanding of medicine in a personal way. “I saw what medicine could do in real time. I watched gastroenterology save the life of someone I loved,” she says.

After her training, Dr. Hahn joined Capital Digestive Care, a large private practice in the Washington, D.C. area, where she spent nearly four years as a partner. She then moved to Los Angeles and joined Cedars-Sinai, where she continued to build her practice and was also named partner. At Cedars-Sinai, she has received numerous “Circle of Friends” gifts, given by patients to recognize physicians for excellent care.

Dr. Hahn frequently cares for patients who have already seen multiple physicians without a clear explanation for their symptoms. Those encounters reinforced an approach that has become central to her practice: when the answer is elusive, start again.

“My job is to start at the beginning. I want to understand the entire story: the testing, the procedures, the medications, and most importantly, the patient’s symptoms. Sometimes finding the answer means being willing to question what has already been assumed,” she says. When meeting new patients, Dr. Hahn’s first question is simple: what matters most to you?

She wants to understand not only the medical history, but also the patient themselves: their routine, concerns, and preferences. “There needs to be personalization in medicine. Two patients can have the same diagnosis but need entirely different treatments,” says Dr. Hahn.

That perspective is especially important in chronic disease. For patients with conditions such as celiac disease or inflammatory bowel disease, treatment is rarely a single decision. It evolves as circumstances change. Dr. Hahn sees herself as a partner in the process, helping patients reassess, adjust, and navigate the inevitable changes that can come with long-term illness.

Throughout her career, Dr. Hahn has watched gastroenterology change dramatically. New therapies, more sophisticated diagnostic tools, and advances in endoscopy have expanded what physicians can offer patients. However, for Dr. Hahn, progress in medicine is not only about having more tools, it is about knowing when and how to use them. She is drawn to Atria’s collaborative model of care, which reflects how she believes medicine should ideally work.

“Atria offers members something that doesn’t currently exist,” Dr. Hahn says. Rather than waiting weeks for specialists to coordinate across different offices, Atria’s care team can look at the patient as a whole and discuss diagnoses and treatments in real time. For Dr. Hahn, good medicine is both rigorous and personal. “Health and medicine have to happen in parallel,” she says. “The best care happens when we are not just treating pathology, but thinking about the patient as a person.”

Dr. Hahn has also used public platforms to educate patients about digestive health. She has contributed to academic journals and had appearances on PBS and web-based educational series. Outside of medicine, Dr. Hahn is a longtime cellist and has performed at Carnegie Hall with the New York Philharmonic and the New York Pops. She is fluent in Korean and enjoys spending time outdoors with her husband and their two children, especially at the beach.