Daily supplementation with vitamin D-3 improved heart function for heart failure patients in the new study.
In the US, around 5.1 million people have heart failure, which occurs when the heart is unable to pump enough oxygen-rich blood around the body to support other organs.
The prognosis for heart failure patients is poor; around 50% of those diagnosed with the condition die within 5 years of diagnosis.
But according to Dr. Klaus Witte, of the University of Leeds School of Medicine in the UK, and colleagues, a daily vitamin D-3 supplement could benefit heart function for patients with chronic heart failure.
The researchers note that patients with heart failure often experience vitamin D deficiency; heart failure is most common among adults aged 65 and older, and older individuals tend to make less vitamin D-3 in response to sunlight than younger individuals.
Improved ejection fraction with vitamin D-3 supplementation
To reach their findings, the team enrolled more than 160 patients who were being treated for heart failure at Leeds Teaching Hospitals National Health Service (NHS) Trust, where Dr. Witte is a consultant cardiologist.
- In 2009, heart failure contributed to 1 in 5 deaths in the US
- Heart failure costs the US around $32 billion annually
- Hypertension, diabetes and coronary heart disease are key risk factors for heart failure.
For 1 year, 80 of the patients were asked to take a vitamin D-3 supplement every day, while the remaining patients were required to take a placebo.
Vitamin D-3, or cholecalciferol, is the form of vitamin D that is produced in the body in response to sunlight exposure.
At the end of the study period, the team used an echocardiogram to measure any changes in patients' heart function, including their ejection fraction - how well the heart pumps out blood with each heartbeat.
A healthy individual will normally have an ejection fraction of 60-70%, but the ejection fraction is impaired among people with heart failure. In this study, patients had an average ejection fraction of 26%.
While heart failure patients who took the placebo showed no improvement in cardiac function, those who took a daily vitamin D-3 supplement showed an improvement in ejection fraction, increasing from 26% to 34%.
Explaining what the results may mean for individuals with heart failure, Dr. Witte says:
"This is a significant breakthrough for patients. It is the first evidence that vitamin D-3 can improve heart function of people with heart muscle weakness - known as heart failure. These findings could make a significant difference to the care of heart failure patients."
The researchers say their results indicate that for some patients with heart disease, regular supplementation with vitamin D-3 may reduce their need for an implantable cardioverter defibrillator (ICD).
An ICD is battery-powered device that is implanted under the skin and connected to the heart with thin wires. The device monitors heart rhythm. On detecting any abnormalities, it delivers an electric shock to the heart, restoring normal rhythm.
"ICDs are expensive and involve an operation," says Dr. Witte. "If we can avoid an ICD implant in just a few patients, then that is a boost to patients and the NHS as a whole."
Medical News Today recently reported on a study suggesting that measuring levels of two components of vitamin D - total vitamin D and bioavailable vitamin D - could predict the risk of poor cardiovascular health.