CHICAGO - The overall amputation rate in northern Illinois is declining due to improved care for diabetes and peripheral vascular disease, new research shows.
But not everyone is reaping the benefits.
A new study from Northwestern University's Feinberg School of Medicine has found people in African American communities on Chicago's South and West Side have a five times higher rate of lower limb amputations than people in the predominantly white suburbs and exurbs.
"Amputations are the canary in the coal mine for quality of care," said Joe Feinglass, lead author and research professor of medicine at the Feinberg School. "Many amputations are preventable. This means the primary care for minority people may not be very good. "
Feinglass said the high rate of amputations means people are not being closely monitored. "They come in with gangrene or a skin ulcer that comes to the attention of a doctor really late and nothing can be done," he said. "They have to take their leg off."
This is the first longitudinal study -- nationally or locally -- to examine amputation trends over nearly 20 years. Most studies of amputation rates look at one point in time.
The study will be published in the May issue of the Journal of Vascular Surgery.
The high amputation rate for minorities in Chicago likely reflects other racial disparities in healthcare, Feinglass said. "Diabetes is a condition that is highly susceptible to quality of care. Amputation rates give you a basic idea of how the system is performing."
It was known in the late 1990's that African Americans were more likely to have an amputation than whites. But as the national trend of amputations declined in the early 2000's, Feinglass wanted to see if the gap closed or at least narrowed.
The study examined hospital discharge data from the Illinois Department of Public Health for nine counties in northern Illinois encompassing more than eight million people. Feinglass then broke the statistics into three rings of the metropolitan area based on their zip codes.
He found that amputations in the suburban and exurban areas with a primarily white population dropped to 12 per 100,000 in 2004 from 14 in 1987. The largely African American area on the South and West Side actually increased to 63 amputations from 60. The inner suburbs and other areas of Chicago, with between 10 and 50 percent African American population and a large Hispanic population, held fairly steady at 20 amputations per 100,000.
About half of the people who have amputations are diabetic patients with decreased circulation to the feet. Almost all who have amputations are smokers, a habit that can cause hardening of the arteries and clots in the legs.
"These people get sores on their feet that don't heal," Feinglass said. "They develop an ulcer that can often turn into something worse if it's not treated right away."
The high amputation rate is linked to lack of access to primary care and specialty care for diabetic patients and patients with vascular disease. In addition, patients without diabetes may not get a screening for peripheral arterial disease, an inexpensive test to indicate risk factors for circulation problems.
To address these problems, Feinglass said communities need diabetes management programs with nurses to help people control their blood sugar.
"Those are the kinds of programs we know would pay off in the inner city. When blood sugar is lower, there is a lower amputation rate," Feinglass said. Vascular surgeons and podiatrists are also needed in these areas.
"An amputation is a horrible thing to have anybody go through," Feinglass said. "We have to do better at preventing these."