Relationship between the obvious asymmetry of the bilateral vertebral arteries and posterior circulation ischemic dizziness

Objective To investigate the relationship between the obvious asymmetry of bilateral vertebral arteries and the occurrence of posterior circulation ischemic dizziness. Methods The patients with posterior circulation ischemic dizziness were enrolled retrospectively. They were divided into either a vertigo group or a non-vertigo dizziness group according to whether they had vertigo or not, and the patients without dizziness were used as a control group. The difference of bilateral vertebral artery diameter more than 10 mm was defined as obvious asymmetry of bilateral vertebral arteries. The demographics, baseline clinical data, and obvious asymmetry of bilateral vertebral arteries of each group were compared. Multivariate logistic regression analysis was used to identify the independent risk factors for posterior circulation ischemic dizziness. Results A total of 117 patients with posterior circulation ischemic dizziness were enrolled, including 43 in the vertigo group and 74 in the non-vertigo dizziness group; 100 patients in the non-dizziness group were used as a control group. There were significant differences in the proportions of patients with hypertension, hyperlipidemia, previous stroke or transient ischemic attack history, and obvious asymmetry of bilateral vertebral arteries, as well as systolic blood pressure, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and fasting blood glucose level between the posterior circulation ischemic vertigo group and the non-vertigo group (all P<0.05). However, multivariate logistic regression analysis showed that obvious asymmetry of bilateral vertebral arteries was not an independent risk factor for the posterior circulation ischemic dizziness (odds ratio 0.260, 95% confidence interval 0.751-2.886; P=0.260)or vertigo(odds ratio 0.506, 95% confidence interval 0.771-6.289; P=0.065). Conclusions Obvious asymmetry of bilateral vertebral arteries is not an independent risk factor for posterior circulation ischemic dizziness and vertigo, and it may be one of the susceptibility factors. Key words: Vertebrobasilar Insufficiency; Dizziness; Vertigo; Vertebral Artery; Ultrasonography, Doppler, Color