HypertensionVitamin D levels

Several studies have found inverse correlations between serum 25(OH)D levels and blood pressure12 as well as risk of developing hypertension34.

Two independent Harvard cohort studies were used to determine the relation between serum 25(OH)D levels and risk of hypertension. There were 613 men from the Health Professionals’ Follow-UP Study and 1198 women from the Nurses’ Health Study who were followed for 4-8 years. During 4 years of follow-up, the multivariable relative risk of incident hypertension among men whose measured plasma 25(OH)D levels were <15 ng/mL (ie, vitamin D deficiency) compared with those whose levels were >30 ng/mL was 6.13 (95% confidence interval [CI]: 1.00 to 37.8). Among women, the same comparison yielded a relative risk of 2.67 (95% CI: 1.05 to 6.79)3. In addition, 2 prospective cohort studies including 38 388 men and 77 531 women with predicted 25(OH)D levels were followed for 16 to 18 years. Using predicted 25(OH)D levels in the larger cohorts, the multivariable relative risks comparing the lowest to highest deciles were 2.31 (95% CI: 2.03 to 2.63) in men and 1.57 (95% CI: 1.44 to 1.72) in women3. Serum 25(OH)D levels were predicted based on a technique involving comparing measured serum 25(OH)D levels with factors that affect serum levels such as oral vitamin D intake, leisure time spent out of doors, skin pigmentation, body mass index, age, and geographical location5.

A subsequent study from the Nurses’ Health Study 2 in which women aged 32 to 52 years who did not have hypertension at baseline were followed from time of blood draw between 1997 and 1999 to 2005 and 742 cases, 742 controls were chosen from a larger pool. Women in the lowest [median (range), ng/mL 16.7 (6.2 to 21.0)] compared with highest [median (range), ng/mL 37.9 (32.3 to 89.5)] quartile of plasma 25(OH)D had an adjusted odds ratio for incident hypertension of 1.66 (95% CI: 1.11 to 2.48; P for trend <0.01). Compared with women with sufficient levels, those with vitamin D deficiency (<30 ng/mL; 65.7% of the study population) had a multivariable odds ratio of 1.47 (95% CI: 1.10 to 1.97)4.

Meta-analysis of eight studies with mean baseline blood pressure was more than 140/90 mmHg showed a nonsignificant reduction in systolic blood pressure in the vitamin D group compared with placebo [-3.6 mmHg, 95% confidence interval (CI) -8.0 to 0.7]. A small, statistically significant reduction was seen in diastolic blood pressure (-3.1 mm Hg, 95% CI -5.5 to -0.6)6.

In a meta-analysis of 3 cohorts, lower 25-hydroxyvitamin D concentration was associated with incident hypertension (relative risk, 1.8 [95% CI, 1.3 to 2.4]). In meta-analyses of 10 trials, supplementation nonsignificantly reduced systolic blood pressure (weighted mean difference, -1.9 mm Hg [CI, -4.2 to 0.4 mm Hg]) and did not affect diastolic blood pressure (weighted mean difference, -0.1 mm Hg [CI, -0.7 to 0.5 mm Hg])7. There was little difference between studies using <1000 IU/d and those using >1000 IU/d, although diastolic pressure change was -1.5 mm for >1000 IU/d vs. 0.1 mm for <1000 IU/d. A meta-analysis of four vitamin D supplementation studies found Vitamin D supplementation reduced systolic blood pressure (SBP) by 2.44 mm Hg (weighted mean difference [WMD]: -2.44, 95% confidence interval [CI]: -4.86, -0.02), but not diastolic blood pressure (DBP) (WMD: -0.02, 95% CI: -4.04, 4.01) compared with calcium or placebo8. The differences between the three meta-analyses arise from the fact that different studies were used in each analysis.

A recent review concluded that the evidence that vitamin D reduces blood pressure is very weak9.

A study in Norway in which sufficient vitamin D was taken orally to increased serum 25(OH)D levels from a mean value of 23 ng/ml to 40 or 55 ng/ml found no effect after one year10.

A meta-analysis including four studies involving hypertensive participants and vitamin D3 found a pooled reduction of 6.2 mm Hg (95% confidence interval, -12.3 to -0.04 mm Hg) systolic6.

In another meta-analysis including nine vitamin D trials and one UVB trial found no significant effect of vitamin D on blood pressure7. However, when only trials involving >1000 IU/d were included, a reduction of diastolic blood pressure of 1.5 mm Hg was found. 

The effect of raising serum 25(OH)D levels is greatest for those with the lowest starting values for cancer11 and cardiovascular disease5. Thus, those with hypertension likely have the lowest serum 25(OH)D levels and would benefit the most.

Page last edited: 09 May 2011

References

  1. Cozzolino, M. Ketteler, M. Zehnder, D. The vitamin D system: a crosstalk between the heart and kidney. Eur J Heart Fail. 2010 Oct; 12 (10): 1031-41.
  2. Zhao, G. Ford, E. S. Li, C. Kris-Etherton, P. M. Etherton, T. D. Balluz, L. S. Independent associations of serum concentrations of 25-hydroxyvitamin D and parathyroid hormone with blood pressure among US adults. J Hypertens. 2010 Sep; 28 (9): 1821-8.
  3. Forman, J. P. Giovannucci, E. Holmes, M. D. Bischoff-Ferrari, H. A. Tworoger, S. S. Willett, W. C. Curhan, G. C. Plasma 25-hydroxyvitamin D levels and risk of incident hypertension. Hypertension. 2007 May; 49 (5): 1063-9.
  4. Forman, J. P. Curhan, G. C. Taylor, E. N. Plasma 25-Hydroxyvitamin D Levels and Risk of Incident Hypertension Among Young Women. Hypertension. 2008 Oct 6;
  5. Giovannucci, E. Liu, Y. Hollis, B. W. Rimm, E. B. 25-hydroxyvitamin D and risk of myocardial infarction in men: a prospective study. Arch Intern Med. 2008 Jun 9; 168 (11): 1174-80.
  6. Witham, M. D. Nadir, M. A. Struthers, A. D. Effect of vitamin D on blood pressure: a systematic review and meta-analysis. J Hypertens. 2009 Oct; 27 (10): 1948-54.
  7. Pittas, A. G. Chung, M. Trikalinos, T. Mitri, J. Brendel, M. Patel, K. Lichtenstein, A. H. Lau, J. Balk, E. M. Systematic review: Vitamin D and cardiometabolic outcomes. Ann Intern Med. 2010 Mar 2; 152 (5): 307-14.
  8. Wu, S. H. Ho, S. C. Zhong, L. Effects of vitamin D supplementation on blood pressure. South Med J. 2010 Aug; 103 (8): 729-37.
  9. Vaidya, A. Forman, J. P. Vitamin D and hypertension: current evidence and future directions. Hypertension. 2010 Nov; 56 (5): 774-9.
  10. Jorde, R. Figenschau, Y. Emaus, N. Hutchinson, M. Grimnes, G. Serum 25-hydroxyvitamin D levels are strongly related to systolic blood pressure but do not predict future hypertension. Hypertension. 2010 Mar; 55 (3): 792-8.
  11. Grant, W. B. Relation between prediagnostic serum 25-hydroxyvitamin D level and incidence of breast, colorectal, and other cancers. J Photochem Photobiol B. 2010 May 12;