Prevalence of moderate and severe asymptomatic extracranial carotid disease in patients with peripheral artery disease: systematic review and meta-analysis

INTRODUCTION: Cerebrovascular accidents are the third biggest cause of death in the West. Ischemic stroke mortality may reach 33% with a 20% recurrence rate in the first year. Thus, identifying patients with asymptomatic extracranial carotid disease (AECD) before cerebral ischemia is of great importance to public health concerns. The paper presents a systematic review and meta-analysis of AECD occurrence in peripheral arterial disease (PAD) patients.EVIDENCE ACQUISITION: A systematic review following designated protocols from “Preferred Reporting Items for Systematic reviews and Meta-analysis” (PRISMA), encompassing research in the PubMed, Medline, Cochrane and Embase data banks. A rigorous evaluation process was concluded with the outcome being the presence of AECD on more than 50% of PAD patients. Nine studies with a total of 114,514 patients were included: 3 prospective studies, 4 retrospective studies, 2 transversal studies were selected for meta-analysis. The stenosis proportion higher than 50% AECD was of 22% with a 95% confidence interval between 16% and 29%; however, its heterogeneity was of I2=98%. Symmetry was identified on funnel plot studies.EVIDENCE SYNTHESIS: The systematic review spanning the last 13 years and the meta-analysis have shown a prevalence of 22% AECD>50% in patients with PAD, leading to reasonable concern over AECD in PAD patients.CONCLUSIONS: However, the heterogeneity within the studies was elevated, probably due to differences in carotid stenosis ultrasound diagnosis procedures among one another.