Pro-A-type and N-terminal pro-B-type natriuretic peptides in different thyroid function states

Area of Science:

• Endocrinology
• Cardiology
• Biochemistry

Background:

• Natriuretic peptides (proANP and NT-proBNP) are cardiac hormones responding to volume and pressure changes.
• Thyroid dysfunctions are associated with various cardiac alterations.
• Investigating natriuretic peptides in thyroid states is crucial for understanding cardiac impact.

Purpose of the Study:

• To investigate mid-regional pro-A-type (proANP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels across different thyroid states.
• To evaluate the effect of L-thyroxine treatment on natriuretic peptides in subclinical hypothyroidism.

Main Methods:

• A case-control study combined with a double-blind, placebo-controlled trial.
• Sera from 161 female patients (hypothyroid, hyperthyroid, euthyroid) were analyzed.
• ProANP and NT-proBNP levels were measured at baseline and after 48 weeks of L-thyroxine treatment in subclinical hypothyroidism patients.

Main Results:

• Hyperthyroid patients exhibited significantly higher proANP and NT-proBNP levels compared to hypothyroid and euthyroid groups (p <0.001).
• ProANP and NT-proBNP levels showed weak correlations with thyroid-stimulating hormone (TSH).
• No significant difference in natriuretic peptide levels was found between subclinical/overt hypothyroid subjects and euthyroid controls; L-thyroxine treatment showed no effect.

Conclusions:

• Natriuretic peptide levels are demonstrably altered in various thyroid states, with hyperthyroidism showing a more pronounced effect.
• Elevated natriuretic peptide levels in hyperthyroidism may mimic mild heart failure symptoms.
• Clinicians should consider hyperthyroidism in patients with unexplained symptoms and elevated natriuretic peptide levels.