Heart failure (HF) is a highly prevalent chronic health condition, affecting approximately 23 million individuals worldwide. In addition, approximately 32 million dollars are spent each year to treat heart failure. Heart failure is the leading cause of hospitalization in people older than 65. It is estimated that one in five adults will develop heart failure after and about half of those who develop heart failure will die within 5 years of diagnosis.
Common symptoms of HF include shortness of breath, chronic wheezing, lightheadedness, nausea, loss of appetite, edema and confusion. If left untreated, HF can lead to kidney damage, liver damage, arrhythmia and eventually death. Though there is no known cure, the symptoms and progression of HF can be managed. Though some cases may be mediated by lifestyle changes such as diet and monitored cardiac rehabilitation, more severe cases may require prescription medication, surgery and the use of implanted devices.
An abundance of research has linked vitamin D status to several aspects of cardiovascular health, including HF. Past studies have determined associations between vitamin D status and HF risk and treatment success. Additionally, some clinical trials have discovered that vitamin D supplementation benefits those living with HF. Due to the high prevalence of vitamin D deficiency in those living with the condition, along with the current evidence supporting a role of vitamin D in managing HF, researchers from this study evaluated the role of vitamin D status in quality of life (QOL) and cardiopulmonary status (CPX) among HF patients.
Researchers in Missoula, Montana gathered participants for this study between fall of 2012 and spring of 2015. Individuals were eligible if they were a class II or class III HF patient, were over 18 years of age, were on stable and guideline directed medical therapy for at least 3 months and had vitamin D levels less than 32 ng/ml. Class of HF is determined based on the severity of the condition.
A total of 36 individuals met these criteria, and thus were included in the study. Of these individuals, 17 were administered 10,000 IU of vitamin D3 per day for six months and 19 were administered an identical placebo pill daily for six months. All participants were evaluated at baseline and at the end of the study. The researchers looked at the following:
- Laboratory values including serum 25(OH)D status, parathyroid hormone, brain natriuretic peptide (BNP) and hsCRP. BNP is a common marker of heart failure, and hsCRP is a marker for inflammation.
- QOL was measured by the Kansas City Cardiomyopathy (KCCQ). The KCCQ evaluates physical function, symptom frequency and severity and social function. Higher KCCQ scores indicates increased QOL.
- CPX was measured by completion of an initial 1-min, constant-rate stair step. Speed and grade were incrementally increased at 1-min intervals. They measured oxygen uptake of all the participants, with higher uptake efficiency being associated with greater heart rate function.
This is what the researchers found:
- By 6 months, vitamin D status rose to 70 ± 28 ng/ml in the treatment group, while the placebo group remained unchanged (20 ± 7 ng/ml).
- BNP improved in the treatment group compared to the placebo group of 19 patients (p=0.003).
- In men, but not in women, the supplement group experienced significantly improved hsCRP levels (p = 0.05).
- Overall KCCQ scores significantly improved in the vitamin D supplement group compared to placebo (p = 0.01).
The researchers concluded,
“Our study suggests that daily vitamin D3, used to replete insufficient stores, may safely improve hormonal factors in heart failure patients like 25(OH)D, BNP, and PTH as well as inflammation.”
“In addition to independent hormonal modulation, sufficient vitamin D3 repletion may provide an important improvement in QOL as an adjuvant treatment to appropriate guideline directed therapy.”
In order to put into perspective, the importance of these findings, the strengths and limitation of this study must be addressed. The researchers utilized a higher dose of vitamin D than seen in most other studies, which aligns with the Vitamin D Council’s recommendations. As seen by the data, 10,000 IU (250 mcg) of vitamin D3 per day was efficient in raising the participant’s vitamin D status to about 70 ng/ml. The researchers noted that should serum 25(OH)D status or calcium levels rise too significantly, the participant would be administered a lower dose, which was not seen in any participants throughout the six months of this study.
However, the major limitation of this study was the small sample size. Further controlled trials are required with a larger sample size in order to determine the effect of vitamin D repletion as adjunct therapy in individuals with stable treatment for heart failure.
Peterson, R. & Cannell, JJ. Quality of life in heart failure is improved by adjunct therapy of 10,000 IU/day vitamin D. The Vitamin D Council Blog & Newsletter, 2017.
Moretti, H.D. et al. Vitamin D3 repletion versus placebo as adjunctive treatment of heart failure patient quality of life and hormonal indices: a randomized, double-blind, placebo-controlled trial. BMC Cardiovascular disorders, 2017.