Evaluation of Regional Geospatial Clusters in Inguinal Hernia Repair

Introduction There is significant variation in how inguinal hernia repairs are conducted across the United States (US). This study seeks to utilize national public data on inguinal hernia repair to determine regional differences in the use of ambulatory surgical centers (ASC) and in the choice of laparoscopic or open technique. Methods Medicare provider billing and enrollee demographic data were merged with US census and economic data to create a county-level database for the years 2014-2019. Location, technique, and total count of all inguinal hernia repair billing were recorded for 1286 counties. Moran's I cluster analysis for inguinal hernia repairs, percent laparoscopic technique, and percent ACS were conducted. Subsequent hotspot and coldspot clusters identified in geospatial analysis were compared using ANOVA across 50 socioeconomic variables with a significance threshold of 0.001.  Results  There were 292,870 inguinal hernia repairs, of which 39.8% were conducted laparoscopically and 21.3% of which were in an ACS. Inguinal hernia repair coldspots were in the Mid-Atlantic and Northern Midwest, while hotspots were in Nebraska, Kansas, and Maryland (3.85 and 36.53 repairs per 1000 beneficiaries, respectively). Compared to coldspots, hotspot areas of repair were less obese, had less tobacco use, older, and less insured; there were no differences in gender, white population, or county urbanization (p<0.001). Laparoscopic technique coldspots were in the Mid-Atlantic, Michigan, and Great Plains, while hotspots were in the Rocky Mountains and contiguous states from Florida to Wisconsin (6.14% and 75.39%, respectively). ACS coldspots were diffusely scattered between Oklahoma and New Hampshire, while hotspots were in California, Colorado, Maryland, Tennessee, and Indiana (0.51% and 48.71%, respectively). Conclusions Inguinal hernia repair, the surgical setting, and the choice of technique demonstrated interesting geospatial trends in our population of interest that have not been previously characterized.