A multi-national cohort study has shown that selenium deficiency in heart failure patients is associated with impaired exercise tolerance and with a 50% higher mortality rate [Bomer].
In-vitro studies of cultured human heart muscle cells from the heart failure patients show that low selenium levels in the heart muscle cells are associated with impaired mitochondrial function [Bomer].
Recent information shows that up to 50% of heart failure patients suffer from some form of micronutrient insufficiency, e.g. selenium, zinc, iron, or iodine [Bomer].
Selenium: An Essential Micronutrient
Selenium intakes and status vary considerably from geographical region to region according to the content of selenium in the soil and in the food.
Sufficient intakes of selenium are necessary for important biological functions:
- antioxidant defense
- immune system function
- thyroid hormone metabolism
Adequate selenium status is also important for the prevention of certain forms of cancer. At the molecular level, the trace element selenium is incorporated into and is essential for the enzymatic action of 25 selenoproteins [Bomer].
Selenium Deficiency and Keshan Disease
Severe deficiencies of selenium are associated with a rare but fatal form of heart disease called Keshan disease. Keshan disease is a form of dilated cardiomyopathy, a disease in which the left ventricle of the heart is enlarged and weakened and is less able to pump adequate quantities of blood out to the body. Keshan disease is reversible with selenium supplementation [Bomer].
BIOSTAT-CHF Multi-National Observational Cohort Study: Selenium and Heart Failure
Dr. Nils Bomer and a team of researchers collected information and samples from 2516 heart failure patients treated in 69 centers in 11 European countries. The heart failure patients in the BIOSTAT-CHF study were patients not yet on guidelines-prescribed treatment (e.g. ACE/angiotensin receptor blockers and/or beta-blockers).
Note: Selenium intakes are generally considerably lower in Europe and the Middle East [Stoffaneller & Morse] than they are in Venezuela, Canada, the United States, and Japan [Bomer].
BIOSTAT-CHF Study Patient Characteristics
The median serum selenium level among the heart failure patients in the study was 87 micrograms per liter [Bomer].
- The 25th percentile level was 73 micrograms per liter.
- The 75th percentile level was 103 micrograms per liter [Bomer].
485 of the 2516 heart failure patients, amounting to 20.4% of all patients, were considered selenium deficient because they had serum selenium concentrations below 70 micrograms per liter. The selenium deficient patients had the following characteristics [Bomer]:
- They were older.
- They were more often women.
- They had worse symptoms and signs of heart failure.
- They were more likely to have anemia, iron deficiency, and chronic kidney failure.
- They had lower serum albumin and lower cholesterol levels.
The selenium deficient patients had greater demonstrable loss of physical function compared to patients with higher serum selenium status [Bomer]:
- They were less likely to complete the 6-minute walk.
- If they did complete the 6-minute walk, they walked a shorter 6-minute distance.
- They had a lower overall score on the Kansas City Cardiomyopathy Questionnaire.
- They had a higher all-cause mortality.
- They had a higher rate of re-hospitalization for heart failure.
In sum, heart failure patients with serum selenium concentrations below 70 micrograms per liter had health problems:
- Poorer quality of life
- Poorer exercise capacity
- Poorer prognosis
Adequate Serum Selenium Concentrations
The BIOSTAT-CHF study results show that heart failure patients with serum selenium concentrations between 70 and 100 micrograms per liter had adverse associations similar to those seen in the heart failure patients with serum selenium concentrations below 70 micrograms per liter [Bomer].
- That suggests that serum selenium levels below 100 micrograms per liter might be considered abnormal [Bomer].
- The relationship between selenium deficiency and the signs and symptoms of heart failure was even stronger than the relationship for iron deficiency [Bomer].
- In the BIOSTAT-CHF study, the data on exercise capacity and quality of life showed a negative effect only at levels below 100 micrograms per liter [Bomer].
BIOSTAT-CHF In-Vitro Studies of Heart Muscle Cells
Seeking an explanation for the association between selenium deficiency and heart failure, the BIOSTAT-CHF researchers carried out some in-vitro experiments using cultured human heart muscle cells from the heart failure patients. The results of the experiments suggest the selenium deficiency disrupts mitochondrial electron transport chain function with the result [Bomer]:
- less efficient ATP production
- increased production of harmful free radicals [Bomer].
The KiSel-10 Study of Combined Selenium and Coenzyme Q10 Supplementation of Senior Citizens
In the KiSel-10 Study, Professor Urban Alehagen and his team of researchers randomly assigned senior citizens aged 70-80 years to take a daily combination of 200 micrograms of selenium and 200 milligrams of Coenzyme Q10 or matching placebos for a median period of 5.1 years.
The daily selenium supplementation increased the senior citizens’ serum selenium levels from 45-87 micrograms per liter at baseline to 185-245 micrograms per liter at 48 months. Placebo treatment did not improve selenium concentrations [Alehagen].
The senior citizens who took the active treatment selenium and Coenzyme Q10 had significant heart function benefits compared to the senior citizens who took the placebos [Alehagen]:
- Lower heart disease mortality
- Lower plasma levels of NT-proBNP bio-markers for heart failure
- Improved echocardiographic function
- Improved health-related quality of life
Conclusion: Selenium Status and Heart Failure
Adequate intakes of selenium and adequate serum selenium status are needed for the maintenance of good health, especially with respect to the maintenance of normal mitochondrial function and normal heart function. Senior citizens are likely to have low serum selenium, which is associated with more severe symptoms and poorer prognosis for heart failure [Bomer].
It may be a good idea to have one’s serum selenium concentration tested to see whether one falls below the 70 and 100 microgram per liter cut-off points.
Sources
Alehagen, U., Johansson, P., Björnstedt, M., Rosén, A., & Dahlström, U. (2013). Cardiovascular mortality and N-terminal-proBNP reduced after combined selenium and Coenzyme Q10 supplementation: a 5-year prospective randomized double-blind placebo-controlled trial among elderly Swedish citizens. International Journal of Cardiology, 167(5), 1860-1866.
Alehagen, U., Aaseth, J., Alexander, J., & Johansson, P. (2018). Still reduced cardiovascular mortality 12 years after supplementation with selenium and coenzyme Q10 for four years: A validation of previous 10-year follow-up results of a prospective randomized double-blind placebo-controlled trial in elderly. Plos One, 13(4), e0193120.
Bomer N, Grote Beverborg N, Hoes MF, Streng KW, Vermeer M, Dokter MM, IJmker J, Anker SD, Cleland JGF, Hillege HL, Lang CC, Ng LL, Samani NJ, Tromp J, van Veldhuisen DJ, Touw DJ, Voors AA & van der Meer P. (2019). Selenium and outcome in heart failure. Eur J Heart Fail. 2019 Dec 6. doi: 10.1002/ejhf.1644. [Epub ahead of print].
Stoffaneller, R. & Morse, N. (2015). A review of dietary selenium intake and selenium status in Europe and the Middle East. Nutrients, 7(3): 1494–1537.
The information presented in this review article is not intended as medical advice and should not be used as such.
3 January 2020