Risk of Ischemic Stroke and Peripheral Arterial Disease in Heterozygous Familial Hypercholesterolemia: A Meta-Analysis

Heterozygous familial hypercholesterolemia (HeFH) is a common genetic disorder predisposing affected individuals to lifelong low-density lipoprotein cholesterol (LDL-C) elevation and coronary heart disease. However, whether HeFH increases the risk of peripheral arterial disease (PAD) and ischemic stroke is undetermined. We examined associations between HeFH and these outcomes in a comprehensive systematic review and meta-analysis. We searched MEDLINE, EMBASE, Global Health, the Cochrane Library, and PubMed (for ahead-of-print publications) for relevant English-language studies. Maximally adjusted risk estimates were pooled under random- and fixed-effects meta-analysis to derive odds ratios (ORs) and 95% confidence intervals (CIs). We included 6 studies representing 183 388 participants. Heterozygnous familial hypercholesterolemia was associated with a higher risk of PAD (OR: 3.59 [95% CI: 1.30-9.89]). This trend was nonsignificantly preserved (OR: 2.96 [95% CI: 0.68-12.88]) in sensitivity analyses of genetically defined HeFH. Genetic HeFH was not associated with increased ischemic stroke risk (OR: 0.76 [95% CI: 0.37-1.58]) although possessing an LDL-C >4.9 mmol/L (190 mg/dL) was (OR: 1.42 [95% CI: 1.06-1.89]). We found clinical and genetic diagnoses of HeFH to be associated with increased PAD risk. Genetically confirmed HeFH may not confer an increased risk of ischemic stroke. Modest associations may exist between LDL-C and ischemic stroke risk in HeFH.