Assistant Professor University of California, Irvine Irvine, California, United States
Disclosure(s):
Matthew J. Landry, PhD, RDN, DipACLM: No relevant financial relationship(s) with ineligible companies to disclose.
Objectives: The burden of diet-related chronic diseases, has intensified the demand for nutrition care services in the United States (US). Registered dietitian nutritionists (RDNs) serve as primary providers of medical nutrition therapy. Current workforce projections suggest the supply of RDNs may not meet increasing patient needs, particularly in underserved areas. The project evaluated geographic coverage of, and access to, RDNs at different geographic levels by age group, urban/rural status, and distances for the adult population.
Methods: We obtained service addresses of RDNs from the 2024 National Provider Identifier (NPI) Registry. While not all RDNs maintain an NPI number, this registry serves as a reliable metric of clinically practicing RDNs. Each RDN's service address was geocoded to obtain corresponding longitude and latitude coordinates. Geographic access to RDNs was assessed using three complementary methods: (1) calculation of the distance between each US Census 2020 block centroid and the nearest RDN location, (2) determination of geographic accessibility, defined as the percentage of the population with access to at least one RDN within specified distance thresholds, and (3) estimation of population-to-RDN ratios for each geographic area.
Results: Approximately 81.6% of adults 18-64 years lived within 5 miles of a RDN, 91% within 10 miles, 97% within 20 miles, and 99% within 50 miles. The percentage of the population with access to one RDN within 20 miles was 99.6% in urban areas and 94% within rural areas. The overall population-to-RDN ratio within 20-miles was 3,270:1 in urban areas and 4,632:1 in rural areas. County-level ratios and percentages of geographic access to a RDN varied greatly across the US.
Conclusions: There were nationwide variations in geographic accessibility to RDNs at county and state levels, as well as disparities in access to a RDN within a reasonable driving distance. This data offers insights into potential communities that may be at risk for health disparities based on limited access to medical nutrition therapy.
Funding Sources: This project was funded by a University of California, Irvine Council on Research, Computing, and Libraries research grant.
