Meta-analysis On The Relationship Between 25-hydroxyvitamin D Level And Primary Hypertsion

Objective:The purpose of this study is to investigate the relationship between25-hydroxyvitaminD(25-(OH)D)and essential hypertension among persons all over the world,which may enhance our knowledge of essential hypertension,will explore a novel pathogenesis for essential hypertension,and may provide a new basic for prevention and treatment of hypertension.Methods:The articles on the association of 25-hydroxyvitamin D level and essential hypertension were collected by searching intemationaI and national databases from2000 to 2018.Eventually there were 14 undepentent studies included by the inclusion and exclusion criteria;we acquired the Extract Values—mean and standard deviation()by the direct means or undirect means;The relationship between 25-hydroxyvitaminD level and essential hypertension was assessed by Meta-analysis with the new Review manager 5.3 softwaroe of Cohrane Community.Firstly,we had a heterogeneity analysis on these undependent studies.If there was no heterogeneity amomg these studies,we adopted Fixed effects model.On the contrary,we adopted Random effects model.We adopted standard mean difference as the only effect size.The Cochran's Q test was used to test the size of the heterogeneity.There was no heterogeneity if P vaule was bigger than 0.10.The opposite result was acquired if P vaule was smaller than 0.10.Finally,we evaluated the degree of heterogeneity for these included studies,and I2 was regarded as the single standard;I 2 was on behalf of the difference of the effect size.I2=0-25%,no heterogeneity;I2=25%~50%,light inhomogeneity;I2=50 %-75 %,medium inhomogeneity;I2 =75 %-100 %,highly-developed inhomogeneity.When I2 was no more than 50%,we applied Fixed effects model;While I2 was more than 50%,we applied Random effects model;Then,we conducted merge and restructuring on these heterogeneity studies;Secondly,weprobed into the sources of heterogeneity on quality of these studies.Finally,puplication bias was evaluated by the funnel plot,Begg's test and Egger's test.Above all,we assessed the relationship between 25-hydroxyvitaminD(25-(OH)D)and hypertension by these means and the effect size.Result:By the heterogeneity test,we drawed the conclusion : chI2=18.24,df=13(p=0.15);I2=29%;We applied the fixed effect model,the mereged effect size as the ED(Std.Mean Difference)was-0.63(95%CI=-0.72~-0.54).The ED was hardly out of the invalid line,The effect size lied in the left side of the invalid line,and Z vaule was 13.95(P<0.00001),which indicated the merged effect size was significant statistically.The result has proved the 25-hydroxyvitaminD level in patients with hypertension is lower than that in control group.Conclusions:25-(OH)D decreased significantly in patients with essential hypertension than that in control group,which proved the relationship between 25-hydroxyvitamin(25-(OH)D)and essential hypertension.But we can not make sure of the specific relationship,for example,causal relationship and so on.We should do more to explore the relationship between 25-hydroxyvit-aminD(25-(OH)D)and hypertension,which will explore a novel pathogenesis for essential hypertension,and provide a new basic for prevention and treatment of primary hypertsion.