As the scope and quality of surgical care continue to advance, there is still much that remains to be done to optimize care for patients. For many conditions, surgery is one of several care options, and in some instances, there are several types of surgical procedures available. Research into the effectiveness and adverse effects of a surgical procedure compared to alternatives are often incomplete. While quality has generally improved over time, outcomes can differ across hospitals and surgeons. Too often, treatment options, whether medical or surgical, are recommended without patients fully understanding the choices and participating in the decision; and these recommendations can vary markedly from one physician to the next. The best strategies to achieve these goals are the focus of quality improvement groups such as the Vascular Quality Initiative, such as amputation or re-intervention procedures. The outcomes data being recorded should go a long way toward producing the kind of widely applicable data upon which patient decision support tools should be based. This Dartmouth Atlas of Health Care series reports on unwarranted regional variation in the care of several conditions for which surgery is one important treatment option.
Finally, the costs of care continue to rise and often differ across health care systems, even the most reputable and prestigious. Why can the “best” surgical care at one academic medical center cost twice as much as another? The next section is concerned with the care of patients after surgery, including hospital re-admissions and ambulatory care.
Patients with diabetes (high blood sugar) and peripheral arterial disease (PAD, or blockages in the arteries of the legs and other locations) are at high risk for major limb amputation at rates several times the national average for patients without diabetes. Nearly 100,000 major leg amputations are performed annually in Medicare patients, and more than half of them occur as a result of diabetes. Co-occurrence of these two illnesses—diabetes and peripheral arterial disease—has a negative synergistic effect, leaving patients at a higher risk for amputation than either of the two diseases alone.
This report examines how Medicare patients with diabetes and PAD are treated across the United States. It describes how, when, and why they may (or may not) be treated with preventive measures, as well as invasive treatments aimed at limiting amputation. By examining these treatment patterns, and outlining the ways in which physicians have attempted to study and improve the care of these complex patients, this study hopes to highlight opportunities to reduce amputations for patients at the highest risk for limb loss.
Data Analysis: While the processes of care for patients with diabetes and PAD are complex, one outcome that matters is easily measurable: major leg amputation, or loss of the leg above or below the knee. In many regions of the United States, amputation rates are quite low, especially in parts of the country where diabetes is uncommon, and among patients who are unlikely to be poor or black.
However, in other regions—for example, rural areas of the southeastern United States—amputation rates, especially among black patients with diabetes, are high. In these regions, the risks of major amputation are often three to four times the national average.
During the period from 2007 to 2011, the national average rate of leg amputation was 2.4 per 1,000 Medicare beneficiaries with diabetes and PAD. This rate varied more than fivefold across hospital referral regions, from 1.2 per 1,000 patients in Royal Oak, Michigan and Sarasota, Florida, to more than 6 per 1,000 patients in Tupelo, Mississippi (6.2) and Appleton, Wisconsin (6.1). Nationally, the amputation rate among black patients—5.6 per 1,000—was nearly three times higher than the rate among other beneficiaries (2.0). The amputation rate varied by a factor of more than seven among black patients, from about 2 per 1,000 in San Diego (2.1) and Las Vegas (2.2) to 14 or more per 1,000 in Lynchburg, Virginia (14.0), Meridian, Mississippi (14.2), and Tupelo (16.1). Among non-black patients (including white, Hispanic, Asian, and others), the amputation rate was less than 1 per 1,000 in Takoma Park, Maryland (0.9) and Royal Oak (0.9) and more than 4 per 1,000 in Lynchburg (4.1) and Tupelo (4.7).
While amputation rates among black patients were higher than others in each of the 306 hospital referral regions, the differences in some were small. For example, in San Antonio, Texas, amputation rates among black and non-black patients were nearly identical during 2007-11 (3.2 and 3.0 per 1,000, respectively). This was a result of the San Antonio region having relatively high amputation rates for non-black patients and below average rates for black patients. By contrast, in Monroe, Louisiana, amputation rates among black patients (7.9) were more than five times higher than among non-black patients (1.5). Tupelo had the highest amputation rates for both black and non-black patients, but the rate among black patients was more than three times higher (16.1 versus 4.7 per 1,000).
The results shown highlight one of the major persistent findings in the care of patients at risk for amputation. Across the United States, the risk of amputation averages between 2 and 3 per 1,000 patients with diabetes and peripheral arterial disease. However, this rate can be up to eight times higher in some places, especially among black patients. In fact, when comparing black and non-black patients, the lowest-risk black patients have a higher risk of amputation than nearly all nonblack patients. These data leave little doubt where the focus on amputation prevention needs to be directed.