Risk factors in patients with ischaemic rest pain of the lower limbs.

One hundred and three consecutive out-patients with ischaemic rest pain were studied. There were 77 men and 26 women with a mean (s.d.) age of 71 (10) years. Thirty-six (35.0%) patients had rest pain alone, 41 (39.8%) in association with an ischaemic ulcer and 26 (25.2%) with digital gangrene. A significantly increased risk of amputation was seen in those patients with an elevated serum cholesterol (greater than 5.2 mmol/l; P = 0.01), white blood cell count of greater than 10 x 10(9)/l (P = 0.05), fibrinogen greater than 4g/l (P = 0.04), and in women with elevated triglyceride levels (greater than 1.8 mmol/l; P less than 0.03). An increased risk of death for all patients was also associated with elevated triglyceride levels (P = 0.03). Few of the women smoked (P less than 0.0004), but they were more likely to have suffered a stroke (P = 0.01). They also had a significantly increased cholesterol level (P = 0.03) and tended to have a higher mortality rate than the men (P = 0.08). Surprisingly, smokers did not have a significantly higher amputation or death rate than non-smokers. Elevated plasma viscosity, packed cell volume, platelet count, haemoglobin and creatinine levels were not independent risk factors for any group. At 30 days after presentation the limb salvage rate was 73% (75/103), amputation was required in 15 (14.6%) cases and 13 (12.6%) patients died. Patients with ischaemic rest pain constitute a heterogeneous group with multiple diseases and risk factors. Early identification and treatment of risk factors may help to improve limb salvage and the mortality rate in this condition.