Analyzing trends of Medicare-participating nurse practitioners and physician associates in the United States from 2017 to 2025

BACKGROUND: The nurse practitioner (NP) and physician associate (PA) workforce in the United States is constantly evolving to meet the changing demands of the U.S. population. PURPOSE: This study aimed to determine how the NP and PA Medicare workforce in the United States has changed from 2017 to 2025 with attention to geographic and temporal trends. METHODOLOGY: Data were obtained on NPs and PAs from the Centers for Medicare and Medicaid Services Doctors and Clinicians national downloadable file (2017-2025). Trends of time series data were assessed using the Mann Kendall Trend Test. Local Indicators of Spatial Association (LISA) mapping of counties identified statistically significant areas with higher and lower NP and PA density than average in 2025. RESULTS: The number of Medicare NPs in the United States rose from 109,100 in 2017 to 252,755 in 2025 (p-value <.001), whereas the number of Medicare PAs increased from 65,500 in 2017 to 123,419 in 2025 (p-value <.001). NPs were more likely to practice in rural areas than PAs. There were clusters of high NP density predominantly in the South and clusters of low NP density throughout the West, whereas there were scattered clusters of high PA density and clusters of low PA density throughout the South. CONCLUSIONS: There have been broad increases in NPs and PAs throughout the United States, although variation persists across geographic regions, degrees of rurality, and demographic characteristics. IMPLICATIONS: These findings can inform initiatives focused on training, recruiting, and retaining Medicare NPs and PAs in underserved regions.