natriuretic-peptide--brain and Thyrotoxicosis

The tissue-specific circulating markers of thyroid hormone action on cardiac function have not been established. Although the relationship between thyroid function and plasma brain natriuretic peptide (BNP) levels has been evaluated in patients with thyroid disorders, the relationship between these parameters in the general population has not been yet studied. We conducted retrospective cohort study by health examination with concurrent measurements of TSH, free T4, body mass index, systolic blood pressure, hemoglobin, and estimated glomerular filtration rate from participants who visited the Department of Health Checkup, Enshu Hospital between July 2008 and March 2017. After participants with abnormal electrocardiogram and/or any history of cardiac disease were excluded, 2,807 individuals were subjected. Multivariate analyses demonstrated that, when compared to euthyroidism (n = 2,629), the increase in BNP levels was significant in overt thyrotoxicosis (n = 21) but not in subclinical thyrotoxicosis (n = 53) or subclinical hypothyroidism (n = 97). Interestingly, the standardized partial regression coefficient was the smallest for thyroid function category (overt thyrotoxicosis compared to euthyroidisim; β = 0.048, p = 0.006) among the independent variables including age, body mass index, systolic blood pressure, and hemoglobin. In longitudinal comparison, we identified 986 participants who had sequential data on the measurements and were stable as euthyroidism and subclinical hypothyroidism. Their annual percent change in BNP demonstrated no significant differences. In conclusion, a direct stimulatory effect of thyroid hormone on the secretion (or production) of BNP was confirmed even in a large number of health examination participants.

Topics: Adult; Aged; Asymptomatic Diseases; Blood Pressure; Body Mass Index; Female; Glomerular Filtration Rate; Hemoglobins; Humans; Hypothyroidism; Male; Middle Aged; Multivariate Analysis; Natriuretic Peptide, Brain; Retrospective Studies; Thyrotoxicosis; Thyrotropin; Thyroxine

A 35-year-old Japanese man was emergently admitted to our hospital with chief complaints of palpitation and dyspnea. He has been treated for Basedow's disease. He was diagnosed with acute decompensated heart failure, atrial fibrillation and thyrotoxicosis. We started anti-thyroid agents and a treatment for heart failure with beta blockers and diuretics under anti-coagulation therapy. His B-type natriuretic peptide levels remained high, although the heart failure had been compensated and the heart rate was well controlled while hyperthyroidism still existed. We should bear in mind that a discrepancy can exist between the clinical course and the B-type natriuretic peptide level in heart failure patients complicated with hyperthyroidism.

Topics: Adrenergic beta-Antagonists; Adult; Anticoagulants; Atrial Fibrillation; Diuretics; Heart Failure; Humans; Hyperthyroidism; Male; Natriuretic Peptide, Brain; Thyrotoxicosis

Serum BNP (brain naturiuretic peptide) and ANP (atrial natriuretic peptide) levels are reportedly elevated in patients with thyrotoxicosis. The increases may not be due to thyrotoxicosis itself but to secondary cardiovascular changes such as chronic heart failure (HF) or atrial fibrillation (AF) which frequently accompany thyrotoxicosis. We measured serum ANP and BNP levels in 130 patients with thyrotoxicosis and correlated them with HF severity and thyroid function. Thirty-seven normal subjects served as controls. Serum BNP levels in thyrotoxic patients were significantly higher than those in control subjects and significantly correlated with serum free T4, free T3 and ANP levels. In untreated Graves' disease serum BNP level was significantly elevated in patients with HF or AF. Multiple regression analysis revealed that HF, free T4, female gender and AF are independent contributing factors to the elevated BNP level, and that these four factors contributed about 40%. On the other hand, HF and AF were contributing variables for ANP level but the overall contribution of these factors was only 10%. After normalization of thyroid function, serum BNP levels were normalized in 70.5% of Graves' patients. BNP level in euthyroid state was dependent on the presence of HF and the BNP value before therapy, but not on thyroid hormone levels or AF. These data suggest that the cardiovascular condition is the major factor responsible for the elevated serum BNP and ANP levels in thyrotoxic patients, while thyrotoxicosis itself is an independent but minor contributing factor. Thus, the determination of serum BNP levels in thyrotoxic patients is useful for monitoring cardiovascular conditions of HF.

Topics: Adult; Aldosterone; Atrial Natriuretic Factor; Case-Control Studies; Female; Graves Disease; Heart Failure; Humans; Male; Middle Aged; Natriuretic Peptide, Brain; Osmolar Concentration; Renin; Renin-Angiotensin System; Thyroid Hormones; Thyrotoxicosis