Risk Factors Predicting Lower Extremity Amputations in Patients With NIDDM

OBJECTIVE To examine the predictors of lower extremity amputation in patients with NIDDM.

RESEARCH DESIGN AND METHODS At baseline, risk factors for amputation were determined in 1,044 NIDDM patients (571 men, 473 women) aged 45 to 64 years. These patients were followed up to 7 years with respect to amputation.

RESULTS The incidence of amputation was 5.6% in men and 5.3% in women. High fasting plasma glucose at baseline examination and the duration of diabetes were associated with a twofold risk for amputation. Similarly, glycemic control measured at baseline by HbA₁ was an important predictor of amputation. There was a dose-response relationship between plasma glucose or HbA₁ and the risk for amputation. The effect of hyperglycemia on the risk of amputation was seen clearly even after the adjustment for other cardiovascular risk factors. Signs of peripheral neuropathy and bilateral absence of Achilles tendon reflexes and vibration sense were important predictors for amputation. Furthermore, absent peripheral artery pulses and femoral artery bruit on auscultation predicted amputation.

CONCLUSIONS Our 7-year follow-up study gives strong evidence that poor glycemic control is an important predictor of amputation in patients with NIDDM in addition to clinically detectable peripheral arterial disease and peripheral neuropathy.