Physician density and hospitalization for inflammatory bowel disease.

BACKGROUND

Inflammatory bowel diseases (IBDs) are chronic illnesses that require frequent and regular healthcare contact. Regular maintenance care may reduce complications or the need for hospitalization. Availability of physicians may be an important determinant of IBD hospitalizations.

METHODS

Using 2008 inpatient data from the Wisconsin Hospital Association, we identified all IBD hospitalizations through ICD-9-CM discharge codes. County-level rates of primary care physicians and gastroenterologists were calculated for each county (using data from the American Medical Association and the US Census Bureau), with counties in the highest tertile by physician density being classified as "high density" counties. Multivariate regression analysis was performed to identify the independent effect of physician density on IBD outcomes.

RESULTS

A total of 26 counties were defined as high density (mean physician density 162/100,000 population; 2090 IBD hospitalizations) with the remaining 46 counties being low density counties (mean physician density 78/100,000 population; 3441 hospitalizations). The overall rate of IBD hospitalizations was similar for residents of high and low density counties. However, hospitalizations from low physician density counties were more likely to have hypovolemia (26% versus 22%, P=0.003), malnutrition (5.6% versus 4.3%, P=0.04), Clostridium difficile infection (4.1% versus 1.9%, P<0.001), require total parenteral nutrition (TPN) (4.3% versus 2.5%, P<0.001), or be admitted emergently (41.5% versus 35.1%, P<0.001). Residence in a county with high physician density was associated with 4% shorter length of stay and 10% lower hospitalization charges.

CONCLUSIONS

Residence in counties with high physician density is associated with less complicated disease on hospitalization and lower hospitalization charges for IBD.