Background: The prognostic role of diabetes, although well established in ischemic heart disease and cerebrovascular disease, was not extensively studied in peripheral artery disease (PAD). Due to the decrease trend in smoking globally, diabetes is fast becoming the major risk factor for PAD. There are accumulating studies showing the association between diabetes and all-cause mortality in peripheral vascular disease. However, the results in these studies were conflicting regarding the impact of diabetes on outcome. (1-3) Therefore, we performed a comprehensive systematic review and meta-analysis to assess the prognostic significance of diabetes to predict all-cause mortality in PAD patients.

Methods: A meta-analysis was conducted to evaluate the association of diabetes with peripheral artery disease outcomes. Using MEDLINE and SCOPUS, we searched for studies published before January 2016. Additionally, studies were identified by manual search of references of original articles or review studies on this topic. In the final analysis, 21 studies with 15,857 patients were included.

Results: Diabetes was associated with a statistically significant increased risk of all-cause mortality (odds ratio: 1.89, 95% confidence interval: 1.51-2.35, p <0.001), without detected publication bias (Egger bias = 0.75, p =0.631). The stronger effect on outcome was obtained in patients with critical limb ischemia (odds ratio: 2.38, 95% confidence interval: 1.22-4.63, p<0.001), as the most severe form of peripheral vascular disease.

Conclusion: Diabetes is associated with an increased risk of mortality in peripheral vascular disease, and the effect is even more pronounced in patients with critical limb ischemia.