Leadership Team - Bridges Health Partners

Robert Zimmerman, MD

President and Chief Medical Officer

Robert Zimmerman, MD is the President and Chief Medical Officer of Bridges Health Partners. Dr. Zimmerman has a wealth of experience in the healthcare industry, spanning over 30 years.

Before assuming his current dual role at Bridges in January of 2023, Dr. Zimmerman served as the Chief Medical Officer at Bridges since 2019. Prior to that, he was the Assistant Medical Director at Excela Health Medical Group in Pennsylvania after spending 14 years on the faculty of the residency program at Latrobe Area Hospital. While there, he led their Population Health efforts to provide more efficient, high-quality, and patient-focused care to the community.

Dr. Zimmerman is a board-certified Family Physician and remains clinically active on a part-time basis in his current role. He obtained his medical degree from Jefferson Medical College of Thomas Jefferson University in 1993 and completed his Family Medicine Residency at Latrobe Area Hospital in 1996. He then served as a physician in the United States Air Force from 1996 to 2000.

With his diverse experience in Family Practice, Population Health, healthcare leadership, and healthcare delivery redesign, Dr. Zimmerman is passionate about improving healthcare outcomes and continues to work tirelessly to achieve that goal.

John Grese

Vice President of Administration

Mr. Grese has 37 years of professional health care management, management consulting, and industrial engineering experience. He currently serves as the Vice President of Administration for Bridges Health Partners Services, LLC, where he is responsible for developing the value based contracting strategy for the organization, which includes leading all efforts in negotiating, implementing, and managing value based provider agreements with national and regional health plans and overseeing all administrative functions of the company. Prior to joining Bridges, Mr. Grese served as Vice President of Provider Networks for Aetna, where he was responsible for overseeing the provider contracting and relations functions for all hospitals, physicians, and ancillary providers in Western Pennsylvania, Central Pennsylvania, and West Virginia. Mr. Grese also held various leadership positions within the West Penn Allegheny Health System, including Director of Managed Care Contracting, Director of Patient Financial Services, Director of the Department of Surgery, and Management Engineer. Mr. Grese’s early career years included management consulting and industrial engineering positions in the Washington DC metropolitan area.

Mr. Grese holds a BS in Industrial Engineering from The Pennsylvania State University and completed the Executive Leadership Program at The Wharton School, University of Pennsylvania.

Kris Hahn

Executive Director, Population Health Operations

Kris Hahn RN, MSN joined Bridges Health Partners in 2017. Kris brings more than 25 years of clinical, program development and software configuration experience. Outside of the clinical arena, much of Kris’ career has been dedicated to driving quality outcomes within the population health industry.

As the Executive Director of Population Health Operations, Kris has responsibility for the development, implementation, and operational oversight of activities in support of care management and quality strategies for the Bridges Health Partners clinically integrated network (“CIN”), Medicare accountable care organization (“ACO”), and population health support organization (‘PHSO”).

Paul Scherrah

Director of Finance

Paul Scherrah, CPA brings more than 15 years of experience to Bridges Health Partners. He joined Bridges in 2019. Mr. Scherrah began his career spending 7 years in public accounting serving primarily in healthcare and higher education. Mr. Scherrah’s prior experience also includes serving as a Manager of Hospital Accounting and Reporting at Allegheny Health Network, Controller at Ohio Valley Hospital, and Manager of Medicare and Medicaid Accounting at Gateway Health Plan. Mr. Scherrah received his Bachelor’s degree from the University of Pittsburgh and became a Certified Public Accountant in 2007.