Vitamin D seems to be the vitamin du jour as various studies have linked it to benefits not only for bone strength, but also to a wide range of ills including cancer, diabetes and high blood pressure. But a recent study published in JAMA Internal Medicine does not support that last link at least not for older people with a particular type of hypertension Isolated Systolic Hypertension, or ISH. This is a common form of hypertension in the elderly, and one that is implicated as a risk factor for heart failure and sudden cardiac death.
People with ISH have an elevated systolic blood pressure the top number while their diastolic pressure is normal. Dr. Miles D. Witham and colleagues, all from Scottish universities and medical centers, examined the effect of vitamin D supplementation in 159 people over 70 years of age who had ISH, and whose blood levels of vitamin D were below normal.
Participants were randomly allocated to two groups. One received 100,000 units of vitamin D (cholecalciferol) every 3 months for one year. The second group received a placebo (an inactive preparation).
At the start of the study, the patients average systolic blood pressure, as measured in doctors offices,was 163 mm Hg. A normal systolic blood pressure is below 140. Although the blood levels of vitamin D increased in the group that received the active supplement, there was no effect on their systolic blood pressures at 3, 6, 9 or 12 months after the study began.
ACSH s Dr. Ruth Kava commented It s disappointing that this well-designed study failed to find an effect. She continued At least for older individuals with ISH, it seems clear that vitamin D, even at high doses, provides no benefit for their hypertension.