Vitamin D and hypertension






Vitamin D, a fat-soluble prohormone, has wide-ranging roles in the regulation of many physiological processes through their interactions with the vitamin D receptors (VDR). It plays a major role in bones and calcium metabolism. Vitamin D deficiency is not uncommon and it has been associated with many health-related issues, including skeletal and non-skeletal complications. The association of low vitamin D and cardiovascular diseases and risk factors has been explored in both animal and human studies. However, studies and trials on the effect of vitamin D supplementation on cardiovascular risk factors and hypertension are conflicting with inconsistent results. Therefore, large, well-powered randomized controlled trials are warranted. If successful, supplementation with easy and low-cost vitamin D can impact our health positively. Here, we summarized the evidence for the association of vitamin D, cardiovascular diseases and risk factors, including coronary artery diseases, stroke, and hypertension, and mortality, with special consideration to resistant hypertension.

There is accumulating evidence for the association between vitamin D and blood pressure. An earlier analysis of NHANES III 1988–1994 of 12,644 participants aged > 20 years showed an inverse association between vitamin D level and blood pressure. Similar results were obtained from analysis of NHANES 2003–2006 of 7228 participants, the Insulin Resistance Atherosclerosis Family Study (IReSFS) , and the Kaiser Permanente Southern California health plan.

Forman and colleagues have also demonstrated an inverse association between vitamin D and risk of incident hypertension from two prospective cohort studies including 613 (followed for 4–8 years) and 38,388 (followed for 16–18 years) men from the Health Professionals’ Follow-Up Study and 1198 (followed for 4–8 years) and 77,531 (followed for 16–18 years) women from the Nurses’ Health Study. Their results, combining men and women with measured 25(OH)D levels, showed a pooled relative risk of 3.18 (95% confidence interval [CI]


Worldwide studies have also demonstrated such an association. In a cross-sectional study of 833 Caucasian males in Uppsala (central Sweden), a threefold higher prevalence of confirmed hypertension was found in participants with 25(OH)D levels < 37.5 nmol/ L. Additionally, a cross-sectional analysis of 1460 participants in Shanghai showed a high prevalence of vitamin D deficiency (55.8%) in middle-aged and elderly Chinese men . In adolescents (aged 13–15), a study of 1441 Peruvians showed an inverse association between vitamin D deficiency and blood pressure, which may predispose risk of HTN later in adulthood.

Comments

Post a Comment

Popular posts from this blog

The Genetic Landscape of Cerebral Steno-Occlusive Arteriopathy and Stroke in Sickle Cell Anemia.

Image
Sickle cell disease (SCD) is one of the most common autosomal recessive diseases in humans, occurring at a frequency of 1 in 365 African-American and 1 in 50 sub-Saharan African births. Despite progress in managing complications of SCD, these remain a major health burden worldwide. Stroke is a common and serious complication of SCD, most often associated with steno-occlusive cerebral arteriopathy, but little is known about its pathogenesis. Transcranial Doppler ultrasonography is currently the only predictive test for the future development of stroke in patients with sickle cell anemia and is used to guide preventative treatment. However, transcranial Doppler ultrasonography does not identify all patients at increased risk for stroke, and progressive arteriopathy may occur despite preventative treatment. While sibling studies have shown a strong genetic contribution to the development of steno-occlusive arteriopathy (SOA) in SCD, the only genome-wide association study
Read more

Does Variability of Brain Blood Flow Increase Stroke Risk in Stroke Survivors and After TIA?

Image
Stroke is the second leading cause of death worldwide, and high blood pressure (BP) is the most important treatable factor that increases a person’s risk of having a stroke. Stiffness of the blood vessels supplying the brain (arterial stiffness), possibly due to long-standing raised BP, is also likely to be a factor that increases stroke risk. Such increased arterial stiffness results in the blood flow through these vessels being more pulsatile (throbs faster) than usual, and this increased pulsatility can be assessed by an ultrasound scan. This research is focused on assessing the relationship between the pulsatility of the blood flow through the blood vessels supplying the brain, and the risk of stroke in patients who have already had a stroke or “mini-stroke” in the past, and in particular to see if this relationship can be explained by raised BP alone. The Oxford Vascular Study (OXVASC) recruits all patients with stroke or “ mini-stroke ” from a single population,
Read more