The effect of vitamin D(3) on blood pressure in people with vitamin D deficiency: A system review and meta-analysis

OBJECTIVE: To evaluate the effect of vitamin D(3) on blood pressure in people with vitamin D deficiency. METHODS: Randomized controlled trials (RCTs) were electronically searched databases including CNKI, VIP, WanFang Data, the Cochrane Library, PubMed, and EMbase which were about oral vitamin D(3) among people with vitamin D deficiency from inception to December 2017. Two reviewers independently screened literature according to the inclusion and extracted data; meta-analysis was performed using RevMan5.3. RESULTS: A total of 17 RCTs with 22 arms involving 1687 participants were included. The results of meta-analysis showed that, there were no significant differences between the vitamin D deficiency group and the control group on the level of change in systolic pressure (ΔSBP) [weighted mean difference (WMD) = −1.94, 95% confidence interval (CI) (−3.93,0.04) P = .06] and on the level of change in diastolic pressure (ΔDBP) [WMD = −0.50, 95% CI (−1.17, 0.17) P = .14]. The results of subgroups showed that, there were statistically significant differences in the age of >50 years subgroup on ΔSBP [WMD = −2.32, 95% CI (−4.39, −0.25) P = .03]; there were statistically significant differences in the hypertension subgroup on ΔSBP [WMD = −6.58, 95% CI (−8.72, −4.44) P <.00001]; there were statistically significant differences in the hypertension subgroup on ΔDBP [WMD = −3.07, 95% CI (−4.66, −1.48) P = .0002]; there were statistically significant differences in the body mass index (BMI) >30 subgroup on ΔSBP [WMD = −3.51, 95% CI (−5.96, −1.07) P = .005]. CONCLUSION: Oral vitamin D(3) has no significant effect on blood pressure in people with vitamin D deficiency. It reduces systolic blood pressure in people with vitamin D deficiency that was older than 50 years old or obese. It reduces systolic blood pressure and diastolic pressure in people with both vitamin D deficiency and hypertension.