The region includes facilities in Raleigh, Holly Springs, Clayton and Smithfield operated by the two entities.
Most recently, Mr. Mathew, who began his career at Chapel Hill-based UNC Health in 2012, served as system vice president of corporate finance for UNC Health.
UNC Health Rex had an additional 18 beds approved at a cost of $8.3 million, according to a Feb. 21 North Carolina Public Radio report.