Diabetes, hypertension, smoking, and hyperlipidemia as risk factors for spontaneous cervical artery dissection: Meta-analysis of case-control studies.

Spontaneous cervical artery dissection (sCeAD) is an important cause of ischemic stroke in the young population and has a different cardiovascular risk profile from other causes of ischemic stroke. No study provided a comprehensive evidence for cardiovascular risk factors of sCeAD. We searched PubMed, MEDLINE, and Embase without date or language restrictions for relevant studies. Bibliographies of included studies were also searched. We included case-control studies where patients with sCeAD were on one arm, and controls were on the other arm. The investigated risk factors were diabetes, hypertension, smoking, and hyperlipidemia. Data extraction and quality assessment were performed independently by two reviewers. Seventeen qualifying case-control studies were identified, comparing 2185 patients with sCeAD and 3185 healthy control subjects. Heterogeneity was low for diabetes, moderate for hypertension and hyperlipidemia, and high for smoking. The meta-analysis showed a significant association between hypertension and sCeAD [pooled odds ratio (OR) = 1.70, 95% confidence interval (CI): 1.40-2.07, P < 0.001]. There was no association between sCeAD and diabetes (pooled OR = 0.71, 95% CI: 0.50-1.01, P = 0.060) or smoking (pooled OR = 0.90, 95% CI: 0.68-1.20, P = 0.480). Hyperlipidemia was negatively-associated with sCeAD (OR = 0.65, 95% CI: 0.48-0.89, P = 0.007), but with sensitivity analysis, there was no association (OR = 0.72, 95% CI: 0.44-1.19, P = 0.200). The meta-analysis reveals that sCeAD has a significant association with hypertension and no association with smoking, diabetes, or hyperlipidemia. These results should direct future research towards exploring biological mechanism of hypertension-induced arterial dissection.