The role of haematological factors in diabetic peripheral arterial disease: the Edinburgh Artery Study

The relationship between haematological factors and peripheral arterial disease (PAD) among diabetics has not been widely examined. 1592 men and women aged 55–74 years were selected from the general population. They underwent an assessment for PAD and a glucose tolerance test. 288 subjects (18.7%) were identified as having diabetes or impaired glucose tolerance (IGT). Among the diabetes/IGT group, median levels of fibrinogen, von Willebrand factor (VWF), tissue plasminogen activator (t-PA), fibrin D-dimer and plasma viscosity were higher in subjects with PAD than those without PAD (P ≤ 0.05). The prevalence of PAD was higher in those with diabetes/IGT (20.6%) compared to those with normal glucose tolerance (12.5%) (odds ratio 1.64; 95% CI 1.17, 2.31). After separate adjustment for fibrinogen, VWF, t-PA, fibrin D-dimer, leucocyte elastase, plasma viscosity and haematocrit, those with diabetes/IGT no longer had a significantly higher risk of PAD compared to those with a normal glucose tolerance test. Simultaneous adjustment for the first four of these haematological factors reduced the risk of PAD among subjects with diabetes/IGT to 1.11 (95% CI 0.76, 1.63). Increased levels of haemostatic factors may partly explain the higher prevalence of PAD in diabetic/IGT subjects compared to normal glucose-tolerant subjects. Future randomized controlled trials involving the indirect lowering of levels of haematological factors should help to explain whether the associations reported here are of causal significance.