June 25, 2025
Daniel Johnson is a medical student at the University of Chicago Pritzker School of Medicine, currently 
taking a gap year between his third and fourth years to conduct research in cardiology and health policy through the Sarnoff Cardiovascular Research Fellowship. He's working in the Health Care Policy Research Section at the Smith Center under the mentorship of Dr. Rishi Wadhera. To shine a light on some of the incredible work he's done while with our group, we asked him a couple of questions:
Why medicine? How has the Smith Center played a role in your journey to become a doctor?
When my sister was 20, she was diagnosed with an atrial septal defect and underwent open heart surgery later that year. As a high school senior with a budding interest in medicine, I found the intricacies of the heart fascinating. Her experience inspired me to pursue cardiovascular research in college and medical school.
Since then, I’ve come to see how cardiovascular disease has touched the lives of nearly everyone, and how health policy can play a powerful role in addressing it at a population level. I wanted to explore research at this intersection more deeply, and working with Rishi at the Smith Center has been the perfect opportunity. It's a unique environment filled with researchers who are not only smart and driven, but also incredibly supportive and generous with their time. They’ve helped me grow tremendously, and the experience has shaped my vision for a career that blends clinical care and research.
What’s one project that you’re proud of?
Private equity firms have been acquiring hospitals across the US, but their impacts on patients with cardiovascular disease, especially heart failure, have been unclear. Under Rishi’s mentorship, I led a quasi-experimental study examining how these acquisitions affect heart failure care and outcomes using Medicare claims data. We found that after private equity acquisition, hospitals selected healthier patients and performed more cardiac catheterizations, but did not improve outcomes. Our study was recently published in JACC, and I’m happy that it contributes to the conversation about the growing corporatization of health care.
What are some of the most important lessons you’ve learned during your time at the Smith Center?
I’ve learned a lot of concrete research skills, like using quasi-experimental methods, coding, and scientific writing, but most of all, I’ve learned about the power of collaboration. The magic of the Smith Center comes from the people here, who make it possible to brainstorm new projects, troubleshoot problems, and learn from experts across disciplines, all in a single day. The outstanding people it attracts and the collaborative culture it fosters have made it a great environment to learn and grow.
What’s next for you and how do you plan to take what you learned at the Smith Center and apply it to future endeavors?
I’m heading back to Chicago to finish my final year of medical school and apply for residency in internal medicine. I plan to continue research in cardiology and health policy, building on the skills and mentorship I’ve gained at the Smith Center.
What's your favorite Smith Center memory?
Every day around 12:30 pm, some of us would gather for lunch, either outside when the weather was nice, or in the conference room when it wasn’t. We often commiserated about our Boston commutes, but it was always a joy to share a meal and laughter together.
As a result of his hard work at the Smith Center, Daniel has published 4 manuscripts and given 6 presentations at national conferences.
Publications:
Prescription Drug Savings with the Expansion of the Out-of-Pocket Spending Cap to Adults with Private Insurance
Daniel Y Johnosn, Archana Tale, Rishi K Wadhera
Journal of General Internal Medicine (2025)
Changes in Physical and Mental Health After the End of SNAP Emergency Allotments
Michael Liu, Daniel Y Johnson, Sara N Bleich, Prihatha R Narasimmaraj, Camilla Bjorck-Posson, Jose F Figueroa, Rishi K Wadhera
JAMA (2025)
Hypertension, Diabetes, and High Cholesterol Awareness Among US Adults
Daniel Y Johnson, Lucas X Marinacci, Rishi K Wadhera
JAMA Cardiology (2025)
Heart Failure Care and Outcomes After Private Equity Acquisition of U.S. Hospitals
Daniel Y Johnson, Michael Liu, Victoria L Bartlett, ZhaoNian Zheng, Andrew S Oseran, Rishi K Wadhera
Journal of the Americal College of Cardiology (2025)
Presentations:
American College of Cardiology Scientific Sessions 2025:
Changes in Cardiac Procedural Utilization and Outcomes for Adults with Heart Failure After Hospital Private Equity Acquisition of US Hospitals (Poster Presentation)
Prescription Drug Savings with the Expansion of the Inflation Reduction Act’s Out-of-Pocket Spending Cap to Privately Insured Adults with Cardiovascular Disease (Oral Presentation)
AcademyHealth Annual Research Meeting 2025: 
Expansion of the Out-of-Pocket Prescription Drug Spending Cap to Private Insurance Would Save 780,000 Adults $2.4 Billion (Poster Presentation)
Changes in Case Mix, Procedural Utilization, and Clinical Outcomes for Heart Failure Patients after Private Equity Acquisitions of Hospitals (Podium Presentation)
Undiagnosed Hypertension, High Cholesterol, and Diabetes Mellitus in US Adults, 2013-2023 (Poster Presentation)
Changes in Physical and Mental Health after the End of SNAP Emergency Allotments (Podium Presentation)