Lower Vitamin D Status Is Associated with an Increased Risk of Ischemic Stroke: A Systematic Review and Meta-Analysis
Nutrients 2018, 10(3), 277; doi:10.3390/nu10030277 (registering DOI)
Ren Zhou 1, Mengying Wang 1OrcID, Hui Huang 1, Wenyong Li 1, Yonghua Hu 1 and Tao Wu 1,2,
1 School of Public Health, Peking University Health Science Center, Beijing 100191, China
2 Key Laboratory of Reproductive Health, Ministry of Health, Beijing 100191, China
- Ischemic Stroke risk reduced by 2.5 if have good level of vitamin D – meta-analysis Feb 2018
- Vitamin D associated with 50 percent less ischemic stroke – meta-analysis Aug 2012
- Cerebrovascular disease 40 percent less likely if high level of vitamin D – meta-analysis Sept 2012
- 50 percent fewer strokes with vitamin D, even though ignored dose size – meta-analysis March 2012
In recent years, accumulating evidence has supported the hypothesis that lower vitamin D status is associated with several known risk factors of stroke. However, the relationship between vitamin D and stroke is still uncertain. To explore if there was an association between vitamin D status and the risk of stroke, a systematic review and a meta-analysis were conducted by searching three databases: Pubmed, Embase, and the Cochrane Library. Following the application of inclusion and exclusion criteria, the relative risk estimates of all the included studies were pooled together to compare the risk of stroke between the lowest and the highest category of vitamin D. The Newcastle–Ottawa Scale (NOS) and the Cochrane Risk of Bias Tool were used to assess the risk of bias, and the publication bias was detected by using a funnel plot and Egger’s test.
Nineteen studies were included and the pooled relative risk was 1.62 (95% CI: 1.34–1.96).
Further analysis found that vitamin D status was associated with ischemic stroke (relative risk = 2.45, 95% CI: 1.56–3.86), but not with hemorrhagic stroke (relative risk = 2.50, 95% CI: 0.87–7.15).
In conclusion, our meta-analysis supported the hypothesis that lower vitamin D status was associated with an increased risk of ischemic stroke. Further studies are required to confirm this association and to explore the association among different subtypes.