A census-based analysis of racial disparities in lower extremity amputation rates in Northern Illinois, 1987-2004.

Background: Given improvements in care for peripheral vascular disease and diabetes over the last two decades, it was of interest whether racial disparities in lower extremity amputation rates had changed.
Methods: Hospital data for 18 years (1987-2004) were used to compute above, below, and through foot amputation rates for over eight million people living in the Chicago metropolitan area. Three areas were created from zip code level census data. Differences in amputation rates were compared between residents of zip code areas that were >50% African American, 10% to 50% African American, or <10% African American.
Results: The largely African American area of the South and West sides of Chicago, with less than 15% of the area population, accounted for 27% of all amputation discharges (n = 33,775) over the 18 years. For all residents of northern Illinois, major (above and below knee) amputation rates declined to 17 per 100,000 residents over the last decade, and both inpatient mortality and length of stay fell throughout the period. However, residents of largely African American zip codes had over five times higher per capita amputation rates than residents of primarily white zip codes.
Conclusions: Racial disparities have remained remarkably constant, despite progress in reducing the overall major amputation rate in northern Illinois. Addressing these disparities will require that low income, medically complex patients at risk of limb loss receive timelier, high performance care, combined with community-based public health and preventive medicine interventions that address the social determinants of health.