Metabolic Syndrome and Risk of Peripheral Arterial Disease: A Systematic Review and Meta-Analysis

This systematic review aimed to evaluate metabolic syndrome as a risk factor for the development of peripheral arterial disease (PAD). We searched in four databases: (1) PubMed, (2) Web of Science, (3) Scopus, and (4) Embase until March 2021. We included cohort studies that evaluated the risk of PAD in patients with and without metabolic syndrome. Study selection, data extraction, and risk of bias analysis were performed independently by 2 authors. We used a random-effects model to conduct a meta-analysis of effect measures [hazard ratio (HR), risk ratio (RR), and odds ratio (OR)]. Individual analyses were performed according to the diagnostic criterion used for metabolic syndrome. We included 7 cohort studies with a total of 43 824 participants. Most of the studies were performed in the general adult population. The metabolic syndrome and PAD diagnostic criteria used in the individual studies were heterogeneous. Almost all studies using RR found an association between metabolic syndrome and the development of PAD (RR: 1.31; confidence interval 95%: 1.03-1.59; I²: 15.6%). On the other hand, almost all the studies that used HR found no association between the two variables. All studies had a low risk of bias. In conclusion, available evidence on the association between metabolic syndrome and the risk of developing PAD is inconsistent. However, given the high prevalence of risk factors that patients with metabolic syndrome have, testing to rule out PAD could be recommended. Future studies should analyze each component of the metabolic syndrome separately and according to the severity of PAD.