Predictors of mortality in patients with peripheral vascular disease. A prospective follow-up study

Background. Peripheral vascular disease is associated with increased cardiovascular mortality and reduced life expectancy. The main causes of death are due to concomitant coronary heart and cerebrovascular disease. Objective. To assess the long-term survival of patients with PVD and to investigate the impact of the presence of risk factors on mortality. Design. Cohort study of patients with intermittent claudication and angiographically established PVD. Baseline investigations were performed in 1990-2; follow-up continued until 1999. Setting. St George's Hospital in South London. Patients. One hundred and ten consecutive patients (66 men and 44 women) referred electively for PVD and who underwent lower limb digital subtraction angiography. Main outcome measures. Survival rates, all-cause mortality. Results. Sixty-one patients (55.4%) died during the follow-up period (26 from cardiovascular causes). The overall five-year survival rate was 52% (95% C.I. 42-62). The survival rate was significantly lower in patients older than 70 years (38% [26-51]) compared to those 70 years or younger (69% [54-80])(p<0.05). The risk of all-cause mortality was almost two-fold in the older than younger age group (sex-adjusted hazards ratio 1.89 [1.08-3.10]). The presence of diabetes at the baseline was an important predictor of survival. After adjusting for age and sex diabetic patients had a hazards ratio of 1.79 (0.96-3.37) compared to non-diabetic patients for all-cause mortality. Further adjustment for hypertension, smoking and renal impairment did not attenuate the risk estimate. Hypertension, smoking and the presence of renal artery stenosis were associated with greater risk of all-cause mortality, although none of these estimates reached statistical significance. Conclusions. Age and presence of diabetes are important independent prognostic factors for increased mortality in patients with peripheral vascular disease.