To assess whether patients with diabetes at high risk for lower extremity amputation received more intensive medical care or self-care instruction and to determine the association between foot care and risk of lower-extremity amputation.
Patients with diabetes were seen at the Seattle Veterans Affairs Medical Center (VAMC) between October 1984 and April 1987; 67 patients were seen for initial non-traumatic amputation, and 236 consecutive control subjects were seen for non-traumatic but medically necessary surgery unrelated to diabetes. Data collection included patient interview and medical record review. High-risk status, defined as presence of peripheral neuropathy, peripheral vascular disease, or prior foot ulcer, was temporally fixed at 2 years before study enrollment.
Peripheral neuropathy, peripheral vascular disease, and prior foot ulcer were independently associated with risk of lower-extremity amputation: peripheral neuropathy odds ratio (OR) = 1.4 (95% confidence interval (CI) 0.7-2.7), peripheral vascular disease OR = 2.6 (95% CI 1.5-4.5), and prior foot ulcer OR = 10.9 (95% CI 4.6-25.5). Patients with a prior foot ulcer were significantly more likely to have seen a podiatrist and to have received outpatient diabetes education at the Seattle VAMC; their providers were more likely to prescribe clipping toenails, regular foot washing, and elevating feet during the day (X12 for proportions P < 0.05). However, for patients with a history of peripheral neuropathy or peripheral vascular disease, there was no statistically significant increase in medical care (podiatry visits, outpatient diabetes education) or self-care instruction (clip nails, elevate feet, or self-monitor blood glucose) compared with patients without either of these two conditions (x12 for proportions P > 0.20).
When clinicians were aware of a patient's very elevated risk for lower-extremity amputation (evidenced by prior history of foot ulcer), they were more likely to prescribe preventive foot-care behaviors, but awareness of other risk factors (peripheral neuropathy or peripheral vascular disease) did not necessarily increase preventive care. Physicians and patients should receive periodic education and reinforcement of diabetes management skills to modify care delivered to individuals at highest risk for lower-extremity amputation.