Molecular Pathways Linking Thyroid Dysfunction, NT-proBNP, and Cardiac Health: A Clinical and Biomarker-based Analysis

Background: Thyroid hormones play a crucial role in cardiovascular function, influencing heart rate, vascular resistance, and myocardial contractility.N-terminal pro B-type natriuretic peptide (NT-proBNP) is a key biomarker of cardiac dysfunction and myocardial stress.This study examines the molecular and biochemical interactions between thyroid dysfunction, NT-proBNP levels, and cardiac health.Objectives: The study has following objectives: to evaluate NT-proBNP levels in hypothyroid, hyperthyroid, and euthyroid individuals, to assess correlations between NT-proBNP and thyroid function markers (TSH, FT3, FT4), to investigate the impact of thyroid dysfunction on cardiac biomarkers, including lipid profile, troponin I, and C-reactive protein (CRP), to elucidate molecular mechanisms linking thyroid hormones with NT-proBNP regulation.To explore the clinical utility of NT-proBNP as a predictor of cardiac dysfunction in thyroid disorders.Materials and methods: A prospective observational study was conducted on 471 participants (157 per group: hypothyroid, hyperthyroid, euthyroid).Laboratory investigations included thyroid function tests, NT-proBNP, lipid profile, troponin I, and CRP.Statistical analyses involved ANOVA, correlation studies, and multivariate regression.Results: N-terminal pro B-type natriuretic peptide (NT-proBNP) levels were significantly elevated in hyperthyroid patients (600 100 pg/mL) compared to hypothyroid (250 50 pg/mL) and euthyroid individuals (100 20 pg/mL).NT-proBNP correlated positively with FT3 (r = 0.76, p < 0.001) and FT4 (r = 0.73, p < 0.001) and negatively with TSH (r = -0.40,p < 0.001).Troponin I showed the strongest correlation with NT-proBNP (r = 0.85, p < 0.001), indicating a link between thyroid dysfunction and myocardial stress.Multiple regression analysis identified FT3, FT4, troponin I, and CRP as significant predictors of NT-proBNP (r = 0.804, p < 0.001).Conclusion: Thyroid dysfunction significantly affects NT-proBNP levels, with hyperthyroidism showing the greatest elevation.The correlation between NT-proBNP, troponin I, and thyroid hormones highlights its potential as a cardiac risk marker in thyroid disease.Integrating NT-proBNP assessment in thyroid disorder management could improve cardiovascular risk stratification and intervention strategies.