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Journal Article 2016; 37(4): 337-342 PubMed PMID: 27857052 Citation  Keywords:  Aged, Aged, 80 and over, Atrial Fibrillation:blood, Case-Control Studies, Cohort Studies, Female, Heart Failure:blood, Humans, Hyperthyroidism:blood, Hypothyroidism:blood, Male, Middle Aged, ROC Curve, Thyroid Function Tests, Thyrotropin:blood, Thyroxine:.   

OBJECTIVE: To fully investigate the thyroid hormonal function in patients with the most common arrhythmia - atrial fibrillation.

MATERIALS AND METHODS: 120 patients (aged 55-85 yrs) with symptoms of congestive heart failure exacerbation and no other concomitant disorders (inclusion criteria: normal cardiac troponin T at admission and 12 hours after, normal renal, hepatic and respiratory function; exclusion criteria: inflammatory state, history of myocardial infarction). Depending on the presence of permanent atrial fibrillation (PAF), patients were divided into two groups: PAF (34 females, 26 males) and regular sinus heart rhythm (43 females, 17 males), the groups did not differ in terms of heart rate, blood pressure, presence of overt/subclinical thyroid dysfunction, and medical therapy used. In all subjects thyroid stimulating hormone, free thyroxine, free triiodothyronine, reverse triiodothyronine were measured; echocardiography was performed.

RESULTS: PAF group showed higher FT4 and rT3 (1.41 vs. 1.27 ng/dl, p=0.0007; 0.61 vs. 0.32 ng/ml, p<0.0001, respectively). With ROC curve analysis the biochemical thyroid related factor of the highest prognostic value for PAF occurrence (with the highest sensitivity and specificity: 77% and 72%, respectively) was rT3 with the cut-off of above 0.3 ng/ml. Also, a positive correlation between rT3 levels and left ventricular posterior wall diameter was observed (Spearman's correlation coefficient 0.33, p=0.0093).

CONCLUSIONS: PAF is another condition where an increase in rT3 is observed. rT3 concentration above 0.3 ng/ml may be a novel biochemical sign associated with the presence of PAF in patients with chronic heart failure....

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Journal Article 2012; 33(5): 517-524 PubMed PMID: 23090270 Citation  Keywords:  Animals, Animals, Newborn, Female, Hypothyroidism:blood, Iodine:toxicity, Lactation, Pregnancy, Prenatal Exposure Delayed Effects:blood, Random Allocation, Sheep, Thyroid Gland:drug effects, Thyrotropin:blood, Thyroxine:blood, Trace Elements:toxicity, Tri.   

OBJECTIVES: The objective of the study was to assess the metabolic risk of excessive dietary iodine intake in ewes and neonatal lambs.

DESIGN: Pregnant Šumava ewes received an experimental diet containing 3.1 mg iodine per kg of dietary dry matter in Group A (control, n=13, 6 ewes and 7 lambs) and 5.1 mg iodine per kg of dietary dry matter in Group B (experimental, n=12, 6 ewes, 6 lambs) for eight months. Iodine was administered to ewes as calcium iodate. TSH in blood serum; TT3, TT4, fT3, and fT4 in blood plasma were examined in both groups of ewes and lambs to assess the risks of iodine intake above the permitted limit, as it applies to thyroid gland activity.

RESULTS: Group B ewes showed a significant increase in TSH and TT4 only on day 1 after parturition. The highest values of TT4, TT3, and fT3 in lambs were recorded on day 1 after birth. The lowest values of fT3 and fT4 in lambs were measured on day 60 after birth with no differences observed between the groups. In lambs of Group B the lower concentration of TSH until day 3 after birth was followed by a significant increase from day 10 after birth.

CONCLUSION: Our results indicate a risk of postnatal hypothyroidism among lambs from pregnant and lactating ewes having a high iodine intake....

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Journal Article 2012; 33(4): 442-445 PubMed PMID: 22936267 Citation  Keywords:  Adolescent, Adult, Aged, Aged, 80 and over, Autoantibodies:blood, Female, Humans, Iodide Peroxidase:immunology, Male, Middle Aged, Thyroid Gland:immunology, Thyroid Nodule:blood, Thyrotropin:blood, Young Adult,.   

OBJECTIVES: The aim of our study was to evaluate the possible association between autoimmunity and thyroid nodular disease (TND).

DESIGN AND SETTING: We conducted a study on 58 patients who were treated in outpatient setting at the Department of Endocrinology, Metabolism and Internal Medicine. Serum samples were analyzed for TSH concentration and anti-TPO antibodies titers. Thyroid ultrasonography was performed in each subject in order to evaluate volume of the gland, and the number and size of nodules.

RESULTS: TND occurred in 70% of anti-TPO positive subjects and in 57.9% of anti-TPO negative subjects, but statistical analysis did not demonstrate a significant concordance between the presence of anti-TPO antibodies and prevalence of TND (p>0.05). We showed that the mean (0.82 vs 0.75; p=0.49), minimal (0.2 vs 0.3; p=0.89) and maximal (2.7 vs 2.4; p=0.49) diameters of a nodule were similar in both groups. Solely in anti-TPO positive patients, anti-TPO titers positively correlated with the number of nodules (p=0.04).

CONCLUSION: Our results favor the role of autoimmunity in TND development although associations between thyroid nodules and thyroid autoimmunity are complicated and may be the subject of much controversy. Increased anti-TPO may influence the number of nodules rather than the presence of TND itself....

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Journal Article 2008; 29(1): 131-136 PubMed PMID: 18283268 Citation  Keywords:  Adult, Case-Control Studies, Female, Humans, Hypothyroidism:blood, Middle Aged, Resistin:blood, Thyrotropin:blood, Thyroxine:blood, Triiodothyronine:blood,.   

OBJECTIVES: Although resistin is involved in metabolism, its role in humans is unclear. Since thyroid status influences metabolism, and since only few studies have evaluated the associations between resistin and thyroid status with inconclusive results, we investigated serum serum resistin levels and their correlations with TSH, FT4 and FT3 in hypothyroid and euthyroid women.

DESIGN AND METHODS: Study group consisted of 22 women with a history of total thyroidectomy and radioiodine ablation performed for thyroid cancer. Controls were 22 healthy euthyroid women matched for age and BMI. After six-weeks of thyroxine withdrawal, subjects were admitted to the Department of Endocrinology of the Poznan University of Medical Sciences to perform this study.

RESULTS: Serum resistin concentrations were lower in hypothyroid patients, 12.40 +/- 5.197 vs. 18.01 +/- 7.31, p=0.0065. In hypothyroid subjects, correlations were as follows: r of -0.2636 and p of 0.248, r of 0.0336 and p of 0.885, and r of 0.3080 and P of 0.174 for resistin and FT4, resistin and FT3, and resistin and TSH, respectively. In controls: r of 0.0311 and p of 0.8908, r of -0.0986 and p of 0.6625, and r of 0.1605 and p of 0.4754 for resistin and FT4, resistin and FT3, and resistin and TSH, respectively.

CONCLUSIONS: Short-term profound hypothyroidism decreased resistin levels. However, no significant correlations between the levels of circulating resistin and thyroid hormones and TSH were shown....

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Journal Article 2008; 29(1): 137-140 PubMed PMID: 18283245 Citation  Keywords:  Adult, Blood Glucose:metabolism, Female, Humans, Hypothyroidism:blood, Insulin:blood, Middle Aged, Severity of Illness Index, Thyroid Gland:physiopathology, Thyroidectomy, Thyrotropin:blood, Thyroxine:blood, Triiodothyronine:blood,.   

OBJECTIVES: Among the peripheral effects of thyroid hormone action, their influence on insulin is of great interest and conflicting data on this subject are available. Despite various studies already performed, of concern is whether insulin levels change in line with a deterioration of thyroid function. In this study, we investigated serum serum insulin levels and their correlations with thyroid-stimulating hormone (TSH), free thyroxine (FT4) and free triiodothyronine (FT3) in hypothyroid women.

DESIGN AND METHODS: Study group consisted of 22 women with a history of total thyroidectomy and radioiodine ablation performed for thyroid cancer, without diabetes or glucose intolerance. After six-weeks of thyroxine withdrawal, subjects were admitted to the Department of Endocrinology of the Poznan University of Medical Sciences to perform this study.

RESULTS: Plasma glucose and insulin were respectively: 4.76+/-0.47 mmol/L and 7.19+/-4.22 microU/mL. Serum TSH, FT4 and FT3 were respectively: 91.66+/-58.59 microU/mL, 2.65+/-2.19 pmol/L, and 1.53+/-1.00 pmol/L. Correlations were: r of -0. 4381 and P of 0.0414, r of -0.2368 and P of 0.2887, and r of 0.3954 and P of 0.0686 for insulin and FT4, insulin and FT3, and insulin and TSH, respectively. The only significant correlation was an inverse correlation between insulin and FT4.

CONCLUSIONS: In profound hypothyroidism insulin concentrations correlate with FT4 only, but not with FT3 or TSH....

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Journal Article 2007; 28(4): 417-421 PubMed PMID: 17693966 Citation  Keywords:  Adult, Body Mass Index, Case-Control Studies, Female, Humans, Hypothyroidism:blood, Leptin:blood, Middle Aged, Thyroid Gland:metabolism, Thyroidectomy:adverse effects, Thyrotropin:blood, Thyroxine:blood, Triiodothyronine:blood,.   

OBJECTIVES: Leptin regulates body weight by suppressing food intake and increasing energy expenditure. Alterations in thyroid hormone levels are also associated with changes in body weight but the effect of thyroid hormone deficiency on serum leptin in humans is unclear.

DESIGN AND METHODS: The aim of this study was to measure leptin levels and to investigate their associations with thyroid hormones in 22 women with severe hypothyroidism after total thyroidectomy, and in a group of 22 healthy euthyroid control female subjects matched for age and body mass index (BMI). Their plasma leptin, free thyroxine, triiodothyronine and TSH were measured.

RESULTS: Leptin levels in subjects and controls were (pg/mL) 18761.64+/-16973.96 and 18729.19+/-18014.05, respectively, p=0.9; leptin did not correlate with free thyroxine, triiodothyroinine and TSH: r=0.1039 and p=0.6453, r=0.0113 and p=0.9602, and r=-0.0525 and p=0.8165 for leptin and FT4, leptin and FT3, and leptin and TSH, respectively in subjects; r=-0.00056 and p=0.9980, r=0.248727 and p=0.2643, and r=-0.046919 and p=0.8357 for leptin and FT4, leptin and FT3, and leptin and TSH, respectively in controls. Leptin levels did not differ between subjects and controls and they did not correlate with thyroid hormones.

CONCLUSIONS: Leptin levels are not influenced by hypothyroidism and do not correlate with thyroid hormones in euthyroid and hypothyroid women....

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Journal Article 2006; 27(1-2): 247-252 PubMed PMID: 16648789 Citation  Keywords:  Adolescent, Adult, Exercise:physiology, Exercise Test, Humans, Testosterone:blood, Thyroid Hormones:blood, Thyrotropin:blood, Thyroxine:blood, Triiodothyronine:blood, Wrestling:physiology, Zinc:pharmacology,.   

OBJECTIVES: The present study aims to investigate how exhaustion exercise affects thyroid hormones and testosterone levels in elite athletes who are supplemented with oral zinc sulfate for 4 weeks.

METHODS: The study included 10 male wrestlers, who had been licensed wrestlers for at least 6 years. Mean age of the wrestlers who volunteered in the study was 18.70 +/- 2.4 years. All subjects were supplemented with oral zinc sulfate (3 mg/kg/day) for 4 weeks in addition to their normal diet. Thyroid hormone and testosterone levels of all subjects were determined as resting and exhaustion before and after zinc supplementation.

RESULTS: Resting TT3, TT4, FT3, FT4 and TSH levels of subjects were higher than the parameters measured after exhaustion exercise before zinc supplementation (p<0.05). Both resting and exhaustion TT3, TT4 and FT3 values after 4-week zinc supplementation were found significantly higher than both of the parameters (resting and exhaustion) measured before zinc supplementation (p<0.05). Resting total testosterone and free testosterone levels before zinc supplementation were significantly higher than exhaustion levels before zinc supplementation (p<0.05). Both resting and exhaustion total and free testosterone levels following 4-week zinc supplementation were found significantly higher than the levels (both resting and exhaustion) measured before zinc supplementation (p<0.05).

CONCLUSION: Findings of our study demonstrate that exhaustion exercise led to a significant inhibition of both thyroid hormones and testosterone concentrations, but that 4-week zinc supplementation prevented this inhibition in wrestlers. In conclusion, physiological doses of zinc administration may benefit performance....

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Clinical Trial 2005; 26(6): 830-834 PubMed PMID: 16380698 Citation  Keywords:  Adult, Analysis of Variance, Energy Metabolism:physiology, Exercise:physiology, Heart Rate:physiology, Humans, Male, Physical Exertion, Reference Values, Statistics, Nonparametric, Thyrotropin:blood, Thyroxine:blood, Triiodothyronine:blood,.   

BACKGROUND: Physical activity influences energy metabolism in human subjects by increasing activity-induced energy expenditure and resting metabolic rate for several hours after exercise. Effects of exercise on circulating thyroid hormone values remain controversial. We have investigated the effect of acute aerobic exercise on thyroid hormone values.

MATERIALS/METHODS: The effect of different intensity levels of acute aerobic exercise on thyroid hormones was investigated in 60 male well-trained athletes by performing bicycle ergometer at 45% (low intensity), 70% (moderate intensity), and 90% (high intensity). These intensities were selected according to their maximum heart rate (MHR). At each intensity level, heart rate, blood lactic acid, serum total thyroxine (T4), free thyroxine (fT4), total triiodothyronine (T3), free triiodothyronine (fT3) and thyroid stimulating hormone (TSH) values were measured.

RESULTS: The results of this study show that exercise performed at the anaerobic threshold (70% of maximum heart rate, lactate level 4.59 +/- 1.75 mmol/l) caused the most prominent changes in the amount of any hormone values. While the rate of T4, fT4, and TSH continued to rise at 90% of maximum heart rate, the rate of T3 and fT3 started to fall.

CONCLUSIONS: Maximal aerobic exercise greatly affects the level of circulating thyroid hormones....

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