Selenium and outcome in heart failure.

Area of Science:

• Cardiology
• Nutritional Science
• Biochemistry

Background:

• Severe selenium deficiency can impair myocardial function.
• The impact of moderate selenium deficiency on heart failure (HF) prognosis is not well understood.

Purpose of the Study:

• To investigate the association between selenium deficiency and clinical outcomes in patients with worsening heart failure.
• To explore potential cellular mechanisms linking selenium deficiency to HF prognosis.

Main Methods:

• Prospective observational cohort study (BIOSTAT-CHF) of patients with worsening HF.
• Serum selenium levels measured using inductively coupled plasma mass spectrometry.
• In vitro study of human cardiomyocytes to assess mitochondrial function and oxidative stress under selenium deprivation.

Main Results:

• 20.4% of patients had selenium deficiency (<70 μg/L).
• Selenium deficiency was associated with older age, female sex, worse NYHA class, poorer exercise capacity, and reduced quality of life.
• Selenium deficiency correlated with increased risk of all-cause mortality (HR 1.52) and HF-related events (HR 1.23).
• In vitro, selenium deprivation impaired cardiomyocyte mitochondrial function and increased oxidative stress.

Conclusions:

• Selenium deficiency in HF patients is independently linked to impaired exercise tolerance and higher mortality.
• Impaired mitochondrial function in cardiomyocytes suggests a cellular mechanism for selenium's role in HF.
• Clinical trials investigating selenium supplementation for HF patients with low selenium levels are warranted.