Plasma selenium concentrations in patients with euthyroid sick syndrome.

Area of Science:

• Endocrinology
• Clinical Nutrition
• Trace Elements

Background:

• Euthyroid sick syndrome is characterized by low serum triiodothyronine (T3) concentrations.
• Selenium is an essential trace element with antioxidant properties, potentially influencing thyroid hormone metabolism.
• Altered thyroid hormone levels are common in critically ill patients, impacting overall metabolic status.

Purpose of the Study:

• To evaluate plasma selenium concentrations in patients with euthyroid sick syndrome.
• To compare selenium status in euthyroid sick syndrome with untreated and treated hypothyroidism.
• To investigate the relationship between selenium levels and thyroid function indices in these patient groups.

Main Methods:

• Plasma selenium concentrations were measured using a validated analytical method.
• Serum triiodothyronine (T3), thyroxine, and albumin levels were determined.
• Statistical analysis was performed to compare selenium levels across different patient groups and assess correlations.

Main Results:

• Plasma selenium concentrations were significantly lower in patients with euthyroid sick syndrome (0.99 +/- 0.37 mumol/L) and treated hypothyroidism (1.09 +/- 0.25 mumol/L) compared to untreated hypothyroidism (1.39 +/- 0.28 mumol/L).
• No significant independent relationship was found between plasma selenium and thyroid function indices (T3, thyroxine).
• Serum albumin concentration showed the strongest association with selenium (r = 0.65), T3 (r = 0.58), and the T3/thyroxine molar ratio (r = 0.64).

Conclusions:

• Decreased plasma selenium in severely ill patients is associated with a hypercatabolic state, as indicated by lower serum albumin.
• Patients with euthyroid sick syndrome and treated hypothyroidism exhibit reduced selenium status.
• Monitoring selenium status and considering supplementation in critically ill patients with low selenium is recommended.