New research published in the Journal of Cardiac Failure reports that vitamin D supplementation lowers aldosterone in heart failure patients.
In the past couple weeks we’ve covered new research in heart failure (HF) a few different times. We reported on an open-label trial out of Iran that found vitamin D supplementation may help decrease the severity of HF. That blog is here. We have also been asking the public to help out researchers at the International Heart Institute of Montana and fund their randomized controlled trial using vitamin D in HF. Their fundraiser is here.
Researchers are interested in vitamin D in HF because people with HF are often deficient in vitamin D, more so than a normal healthy population. Low vitamin D levels correlate with worse outcomes for those with HF, and again, a few open-label trials have shown vitamin D supplementation might help with HF severity.
In the present study, researchers from the University of Colorado School of Medicine enrolled 64 patients with HF into their randomized controlled trial. The patients had to be over 50 years old, meet the criteria for HF and have a vitamin D level of less than 37.5 ng/ml at the start of the trial.
The patients were randomized to receive either 50,000 IU of vitamin D3 once per week for 6 months or placebo. All patients also received 800 mg of calcium citrate daily.
The researchers measured the following at baseline and after 6 months:
- Vitamin D levels
- Aldosterone, which is a steroid hormone that plays a central role in regulating blood pressure. Research shows blockade of aldosterone improves outcomes in patients with HF.
- NT-proBNP, which is a peptide that increases with reducing left ventricular ejection fraction. A low ejection fraction is a central characteristic of heart failure and describes the heart’s inability to pump blood to the rest of the body. So, the higher the NT-proBNP, the worse the ejection fraction.
- Plasma renin activity (PRA). PRA is a marker of renin-angiotensin system activation, and high levels have been linked to adverse outcomes in HF.
- High-sensitivity C-reactive protein (hs-CRP). hs-CRP is a marker of inflammation in HF.
- Various variables measured by an echocardiogram. One such variable was the ejection fraction rate.
- Health status, as measured by a scale specific for HF. The scale is called the KCCQ, a self-administered scale that measures symptoms, physical limitations, social function and quality of life all in relation to HF.
They wanted to know if any of these measures that describe the severity of HF improved over the 6 months. Here’s what they found:
- Vitamin D levels increased by 42.3 ng/ml in the vitamin D group, while they didn’t change in the placebo group.
- Serum aldosterone changed from 10.0 ng/dl to 6.3 (37% reduction) in the vitamin D group, while hovering around 6 ng/dl in the placebo group (p=.02).
- PRA decreased slightly in the vitamin D group from 7.6 ng/ml/hr to 6.3 ng/ml/hr and increased in the placebo group from 6.7 ng/ml/hr to 9.2 ng/ml/hr (p=.2 for change between the groups).
- There were no changes in any echocardiographic variables within or between groups.
- There was no significant change between baseline and 6 month hs-CRP, NT-proBNP, or health status according to the KCCQ.
The researchers concluded,
“A robust change in serum 25OHD with a decrease in PTH resulted in a modest decrease in serum aldosterone in patients with HF without a statistically significant clinical benefit. Vitamin D3 as an adjunct to standard HF therapy requires further study.”
We do indeed need more research in the area to find out if and why vitamin D helps in HF. Which is all the more reason to consider donating to the International Heart Institute of Montana research project mentioned above.
Boxer, R. S., Hoit, B. D., Schmotzer, B. J., Stefano, G. T., Gomes, A., & Negrea, L. The Effect of Vitamin D on Aldosterone and Health Status in Patients with Heart Failure. Journal of Cardiac Failure, 2014.