Thyroid Hormone Levels In Patients Research Articles

Decreased levothyroxine requirement in women with hypothyroidism during androgen therapy for breast cancer.

To determine the effects of androgen administration on measures of thyroid function and thyroid hormone replacement doses in women with breast cancer. Consecutive patients with metastatic, hormone-dependent breast cancer who were eligible for androgen treatment. Androgen therapy (fluoxymesterone, 10 mg orally twice daily) was continued for as long as it was effective in controlling tumor growth. 7 patients with no known thyroid disease and 4 others receiving long-term treatment for hypothyroidism. Serum levels of total and free thyroxine (T4), thyroid-stimulating hormone (TSH), and T4-binding globulin were determined before and every 4 weeks after androgen therapy was initiated. Within 4 weeks of androgen administration to the seven patients without thyroid disease, serum levels of total T4 and T4-binding globulin decreased (P < 0.001), whereas the calculated free thyroxine index and measured free hormone levels remained unchanged. Six to 12 weeks after androgen therapy was discontinued, all seven patients remained clinically euthyroid, and serum levels returned to baseline values. In contrast, clinical hyperthyroidism developed shortly after androgen was administered to four patients who received long-term thyroid hormone replacement therapy. Within 4 weeks of treatment, the serum free T4 level increased in each of the four patients, whereas the TSH level decreased. Thyroid hormone doses had to be reduced by 25% to 50% to maintain euthyroidism. The study documents the reversible effects of androgens on thyroid hormone levels and indicates the need to reduce thyroid replacement doses in women during androgen therapy. Monitoring thyroid hormone levels in patients receiving replacement therapy and perhaps in those with autonomous thyroid function is necessary after androgen therapy.

The mechanism of thyroid hormone abnormalities in patients with diabetes mellitus

In order to clarify the mechanism of impaired thyroid hormone levels in patients with diabetes mellitus, thyroid hormone, thyroid hormone binding inhibitor (THBI), inhibitor of extrathyroidal conversion of T4 to T3 (IEC) and free fatty acid (FFA) were examined. In addition, TRH test was performed on 9 diabetic patients showing poor control of plasma glucose before and after glycemic control. Before glycemic control, fasting plasma glucose and HbA1c were significantly higher than after glycemic control (P < 0.05). T3 and the T3/T4 ratio significantly increased and rT3 significantly decreased after glycemic control (P < 0.05). THBI index and plasma FFA level significantly decreased and %T3 production (IEC) significantly increased after glycemic control (P < 0.05). The response of TSH to TRH significantly increased after glycemic control. In conclusion, (1) the presence of THBI, (2) the presence of IEC, and (3) dysfunction of the hypothalamo-hypophysial-thyroid axis are considered to be involved in abnormal thyroid function in diabetic patients.

Inhibition of metabolic activity of polymorphonuclear granulocytes by thyroid stimulating antibodies.

Both thyrocytes and polymorphonuclear granulocytes (PMNs) are known to have on their surface thyrotropin receptor (TSH-R). Anti-TSH-R antibodies having stimulating and blocking effects on thyroid function have been detected in sera of Graves' patients. Thyroid stimulating anti-TSH-R antibodies (TSAb) are involved in the pathomechanism of thyrotoxicosis. The basic question is in this study whether TSAb exerts effects on metabolic activity of PMNs. Immunoglobulin G (IgGs) of 32 patients with thyrotoxicosis had significant inhibitory effect (p less than 0.001) on chemiluminescence of healthy PMNs compared to controls. An inverse correlation was observed between inhibitory effect of IgGs on function of PMNs and TT4 (r = -0.61) in contrast to anti-TSH-receptors antibodies (r = 0.09). TSAbs of eight hyperthyroid patients were measured by determination of cyclic AMP in suspension and slices of porcine thyroid gland. Function of human PMNs separated from healthy donors was determined by luminol-amplified chemiluminescence. Photon-emission of PMNs induced by adherence was significantly lower than that of controls. None of patients' IgGs contained anti-PMNs antibodies or other toxic compounds. It was found an inverse correlation between chemiluminescence of PMNs and capability of TSAb to increase intracellular cAMP in thyroid slices and the thyroid hormone levels of patients with thyrotoxicosis (p = 0.0005). In conclusion, TSH-R on PMNs did not belong to "mute" receptors and metabolic changes in PMNs induced by TSAb might have pathogenetic as well as methodological implications.

Erythrocyte Sorbitol Levels in Patients with Thyrotoxicosis

Hyperglycemia and impaired glucose tolerance are frequently observed in patients with hyperthyroidism. However, little is known about whether altered polyol metabolism in hyperthyroidism is present or not. To examine changes in polyol metabolism in hyperthyroidism, we investigated changes in erythrocyte sorbitol, glyceraldehyde reductase (GAR) and sorbitol dehydrogenase (SDH) activities during hyperthyroid and euthyroid states in patients with thyrotoxicosis. Mean levels of erythrocyte sorbitol and GAR were 32.0 +/- 1.6nM/g.Hb and 147.1 +/- 0.3mU/g.Hb, respectively. In thyrotoxic patients in a hyperthyroid state, these values were significantly higher than those in euthyroid controls. Mean level of erythrocyte SDH in thyrotoxic patients was weak but was significantly increased in comparison with that of euthyroid controls. However, mean levels of erythrocyte sorbitol and GAR were remarkably reduced to 23.6 +/- 1.4nM/g.Hb and 125.3 +/- 4.6mU/g.Hb in thyrotoxic patients in a euthyroid state after treatment with anti-thyroid drugs or by subtotal thyroidectomy. Mean level of SDH, on the other hand, was increased after the treatment. In addition, positive correlations were observed between the level of erythrocyte sorbitol or GAR, and the level of free thyroxine(FT4) or free triiodothyronine(FT3). A negative correlation was observed between the level of erythrocyte SDH and the level of FT4 or FT3. These results suggest that the level of erythrocyte sorbitol may be increased through direct acceleration of erythrocyte GAR activity by increased thyroid hormone levels in patients with thyrotoxicosis.

Suppressed Serum TSH with Normal Free Thyroid Hormone Levels in Patients with No History of Thyroid Disorder

Suppressed Serum TSH with Normal Free Thyroid Hormone Levels in Patients with No History of Thyroid Disorder

Thyroid functions before and after maintenance hemodialysis in patients with chronic renal failure.

To study the factors involved in the low thyroid hormone levels in patients with chronic renal failure (CRF), we investigated thyroid functions just before and after hemodialyses (HD) in 32 such patients who were on maintenance HD. In addition, we measured serum thyroid hormone binding inhibitor activities (THBI) in another set of 37 patients. None of the patients had been suspected of having thyroid diseases. HD duration and aging did not have a significant effect on the results of the thyroid function tests. Before each HD, the serum concentrations of T3, T4, FT3, FT4, rT3, PBI, FT3I, FT4I, FT3/T3, FT4/T4, T4/TBG, T4/TSH and FT4/TSH were lower, and those of TSH, TBG, and thyroglobulin (Tg) were higher in the patients than in normal controls. The thyroid hormone concentrations were negatively correlated with the BUN and creatinine levels. The Tg levels were positively correlated with the BUN levels. After each HD, almost all the thyroid function tests including T4/TBG ratio showed improvements, which indicated that hemodilution and a decrease in the T4-binding affinity of TBG with thyroid hormones were the major factors in the low thyroid hormone levels in CRF patients. However, even after HD, T3, FT3, rT3, T4/TSH and FT4/TSH were still lower and TSH and Tg were still higher in the patients. These data suggested that the CRF patients were in a subclinical hypothyroid state. THBI was high in patients with CRF and did not change following HD. NEFA did not seem to contribute to the high THBI before HD, because they were in the normal range. However, as NEFA became very high after HD and possessed THBI, we calculated the corrected THBI (C-THBI) by subtracting the effect of NEFA from total THBI. C-THBI was high before HD and decreased after HD. Therefore, it was suggested that this C-THBI contributed to the abnormalities in the affinity of TBG with thyroid hormones. From these studies, it is concluded that (1) the patients with CRF may be in a subclinical hypothyroid state, although hemodilution was seen to have a strong effect on the thyroid hormone concentrations, and (2) C-THBI may have an effect on the affinity of TBG with thyroid hormones and play an additional role in low thyroid hormone levels in these patients. The mechanisms of hypothyroidism and the nature of C-THBI remain to be clarified.

Thyroid hormone levels in patients with slipped capital femoral epiphysis.

Twelve patients with slipped capital femoral epiphysis and 12 age- and sex-matched controls were prospectively studied. Their height, weight, skeletal maturation, and thyroid status were assessed. The duration of symptoms and severity of the slip was recorded in the test group. There was no correlation between duration of symptoms and severity of the slip or delay in making the diagnosis and severity. Although 50 percent of patients with slipped capital femoral epiphysis were over the 90th percentile for weight, there was no overall significant difference in weight, height, or skeletal maturation between the two groups. There was no evidence of either overt or subclinical hypothyroidism in patients with slipped capital femoral epiphysis.

Serum thyroid hormone levels in patients with fulminant hepatitis: usefulness of rT3 and the rT3/T3 ratio as prognostic indices.

To evaluate thyroid function in 19 patients with fulminant hepatitis (FH), we have measured total and free 3,5,3'-triiodothyronine (T3) and thyroxine (T4), 3,3',5'-triiodothyronine (reverse T3, rT3), thyroid-stimulating hormone (TSH) and thyroxin-binding globulin (TBG) in patients with FH, compared with those of 80 patients with other various liver diseases and of 10 healthy controls. Patients with FH showed the lowest values of serum T3 and the highest levels of rT3 among all patients with liver diseases studied. Furthermore, patients with FH showed a significant increase of rT3 in comparison with subacute hepatitis (SAH), "acute-on-chronic" (AOC) type of hepatic failure, ordinary and severe forms of acute hepatitis (AHo and AHs) and decompensated liver cirrhosis (LC-D). In addition, serum T3 and rT3 and the rT3/T3 ratio significantly correlated with prothrombin time (PT) and plasma methionine level. We also found that serum T3 and rT3 concentrations and the rT3/T3 ratio showed early and rapid normalization in cases of FH that survived, but they did not improve in patients with fatal outcome. These results suggest that serum T3, particularly rT3 concentrations and the rT3/T3 ratio may be useful indicators for assessing the severity and prognosis of patients with FH and can be considered to the sensitive indices for functioning hepatic microsomal reserve as well.

Change in Serum Thyroid Hormone Level in Patients with Acute Myocardial Infarction

It has been reported that there is a decrease in the serum concentration of thyroid hormones in non-thyroidal illness. In the present study we made serial measurements of serum concentration of thyroid hormones [triiodothyronine (T3), thyroxine (T4), free triiodothyronine (FT3), free thyroxine (FT4), reverse triiodothyronine (rT3)], thyroid stimulating hormone (TSH) and thyroxine binding globulin (TBG) in 10 patients with acute myocardial infarction (AMI, Grade I, according to the classification of Killip & Forrester) during 14 days after onset. In the early phase of AMI, serum T3, T4, FT3 and FT4 levels decreased while rT3 increased. TSH and TBG levels, however, were unchanged. In the patients with a high peak creatine phosphokinase activity (greater than or equal to 400 mU/ml), the decrease in thyroid hormone and increase in serum rT3 levels were greater than in patients with a low peak value (less than 400 mU/ml), suggesting a correlation between severity of AMI and changes in serum thyroid hormone levels. Especially, serum FT3 levels fell below the lower limit of controls within 14 days, with the lowest levels and the rT3 peak on the third day after onset. These data suggest that in AMI peripheral conversion of T4 favours rT3 production and that low levels of serum FT3 and T3 protect the infarcted heart muscle against thyroid hormone action.

Serum and peritoneal dialysate thyroid hormone levels in patients on continuous ambulatory peritoneal dialysis.

Thyroid function tests were performed on 16 clinically euthyroid patients with end-stage renal failure undergoing regular haemodialysis or continuous ambulatory peritoneal dialysis and compared with 8 healthy subjects. The patient groups were carefully matched, especially regarding relative duration of dialysis (mean of 24 months). Total serum thyroxine, total triiodothyronine, free thyroxine, free triiodothyronine and reverse triiodothyronine were significantly lower in both patient groups than control. The thyrothrophin response to the standard thyrotrophin-releasing hormone test was delayed and blunted. Using a novel concentration technique we measured loss of T4 in peritoneal dialysate effluent and found it to be approximately 10% of daily thyroidal T4 release.

Prognostic value of thyroid hormone levels in patients evaluated for liver transplantation.

The thyroid hormones T4, T3, rT3 and TSH were assayed in 134 adult patients evaluated and accepted as potential liver transplant candidates at the University of Pittsburgh from March, 1981 to December, 1983. The subsequent course of these patients was evaluated with respect to the levels of these hormones obtained at the time of acceptance for transplantation. T4 levels were increased significantly while their T3 levels were reduced (both p less than 0.01) in those who survived and were discharged home as compared to either those who died waiting to be transplanted or died following the procedure. As a result, the ratio of T3/T4 was reduced markedly (p less than 0.01) in those who were transplanted and survived as compared to those not transplanted or dying following transplantation. Importantly, the rT3 levels clearly separated (p less than 0.01) those who would die prior to transplantation from those who would survive to be transplanted. Finally, the ratio rT3/T3 even more clearly separates those who will die prior to transplantation (p less than 0.01) from the other two groups. These data suggest that thyroid hormone levels, particularly rT3 levels, might be useful in setting priorities for which patients referred for a transplantation evaluation should be accepted into the program and in determining who among accepted patients should be operated upon in preference to others also accepted and waiting to be transplanted.

Serum thyroid hormone levels in patients on continuous ambulatory peritoneal dialysis and regular hemodialysis.

In vitro thyroid function tests were performed on clinically euthyroid patients undergoing regular hemodialysis (HD) or continuous ambulatory peritoneal dialysis (CAPD). The mean serum total thyroxine (TT4) and total triiodothyronine (TT3) values measured before HD were significantly subnormal. Similarly, CAPD subjects had reduced TT3 concentrations with low normal TT4 levels. Free thyroxine measurements, estimated by two different methods were aberrant in CAPD patients. Low normal reverse triiodothyronine (rT3) values were found in HD, in contrast to high normal rT3 levels in CAPD. Thyroid stimulating hormone determinations were normal, corresponding with the euthyroid status in both patient groups.

Tricyclic antidepressants do not alter thyroid hormone levels in patients suffering from a major affective disorder

Abnormalities of thyroid function have been associated with affective disorders, and treatment with thyroid hormones or drugs that alter thyroid hormone levels can change the course of an affective disorder. Therefore, we investigated the possibility that mood-altering effects of tricyclic antidepressants would be mediated by alterations in thyroid hormone (T 3 and T 4) levels. In a group of 11 patients with affective disorders, tricyclic antidepressants did not alter serum T 3 and T 4 levels. We conclude that the mood-altering potency of tricyclic antidepressants, and particularly their potency to induce rapid mood cycles, is not due to changes in total T 3 and T 4 serum levels.

Serum thyroid hormone levels in patients with liver disease

Levels of serum triiodothyronine (T₃), reverse triiodothyronine (rT₃), and thyroxine (T₄) were determined in 29 patients with alcoholic cirrhosis, seven patients with acute hepatitis, and 14 control patients hospitalized for chronic disease. Serum T₃levels were decreased significantly and serum rT₃levels increased significantly in the patients with alcoholic cirrhosis. Serum T₃and T₄levels were lower and rT₃levels higher in the cirrhotic patients who died within three months of the study compared with those who survived. A combination of prothrombin time, aminopyrine breath test results, and rT₃and T₃determinations gave significant predictive information about survival in patients with cirrhosis. The data suggest that assay of serum thyroid hormone levels together with prothrombin time and the aminopyrine breath test may be helpful in assessing the course and prognosis of patients with liver disease. (<i>Arch Intern Med</i>139:1117-1120, 1979)

Serum Thyroid Hormone Levels in Patients With Liver Disease

Levels of serum triiodothyronine (T3), reverse triiodothyronine (rT3), and thyroxine (T4) were determined in 29 patients with alcoholic cirrhosis, seven patients with acute hepatitis, and 14 control patients hospitalized for chronic disease. Serum T3 levels were decreased significantly and serum rT3 levels increased significantly in the patients with alcoholic cirrhosis. Serum T3 and T4 levels were lower and rT3 levels higher in the cirrhotic patients who died within three months of the study compared with those who survived. A combination of prothrombin time, aminopyrine breath test results, and rT3 and T3 determinations gave significant predictive information about survival in patients with cirrhosis. The data suggest that assay of serum thyroid hormone levels together with prothrombin time and the aminopyrine breath test may be helpful in assessing the course and prognosis of patients with liver disease.

Sinemet and thyroid function in Parkinson disease.

Patients on chronic carbidopa-levodopa (Sinemet) therapy underwent thyroid function testing that included measurement of serum thyroxine (T4), triiodothyronine (t3), thyrotropin (TSH), T3 uptake (T3U), free T4 index (FT4I), and free T3 index (FT3I). The subjects were studied both in a random sampling and in a controlled manner, fasting and 2 hours after receiving the drug. All subjects were euthyroid by testing, and there was no significant difference in thyroid hormone levels of patients and controls or in fasting values and values 2 hours after the drug. However, there was a small but significant reduction in serum TSH levels after Sinemet. Therapeutic doses of Sinemet have no significant effect on thyroid function in euthyroid patients with Parkinson disease.

Red cell 2,3-diphosphoglycerate and oxygen affinity of hemoglobin in patients with thyroid disorders

We measured red blood cell 2,3-diphosphoglycerate (2,3-DPG), adenosine triphosphate (ATP), and the P50 value in vitro of the oxyhemoglobin dissociation curve, which is the oxygen tension at half saturation of hemoglobin, in order to quantitate red blood cell oxygen transport function in individuals who were diagnosed as hypothyroid, euthyroid, or hyperthyroid based on measurements of thyroxine (T4), triiodothyronine (T3), thyrotropin (TSH), and their clinical status. Hypothyroid (mean T4 2.8 microgram/dl, T3 49 ng/dl, TSH 37 microU/ml) and hyperthyroid (mean T4 14 microgram/dl, T3 271 ng/dl, TSH less than 0.7 microU/ml) patients had normal red cell 2,3-DPG and ATP levels and normal P50 values in vitro. The known changes in oxygen consumption produced by alterations in thyroid hormone levels in patients with hypothyroidism or hyperthyroidism did not affect red blood cell oxygen transport function.

Red Cell 2,3-Diphosphoglycerate and Oxygen Affinity of Hemoglobin in Patients With Thyroid Disorders

Abstract We measured red blood cell 2,3-diphosphoglycerate (2,3-DPG), adenosine triphosphate (ATP), and the P50 value in vitro of the oxyhemoglobin dissociation curve, which is the oxygen tension at half saturation of hemoglobin, in order to quantitate red blood cell oxygen transport function in individuals who were diagnosed as hypothyroid, euthyroid, or hyperthyroid based on measurements of thyroxine (T4), triiodothyronine (T3), thyrotropin (TSH), and their clinical status. Hypothyroid (mean T4 2.8 microgram/dl, T3 49 ng/dl, TSH 37 microU/ml) and hyperthyroid (mean T4 14 microgram/dl, T3 271 ng/dl, TSH less than 0.7 microU/ml) patients had normal red cell 2,3-DPG and ATP levels and normal P50 values in vitro. The known changes in oxygen consumption produced by alterations in thyroid hormone levels in patients with hypothyroidism or hyperthyroidism did not affect red blood cell oxygen transport function.

The effect of body temperature on thyroid hormone levels in patients with non-thyroidal illness.

During studies on the mechanism underlying the low serum T3 levels in euthyroid patients with various acute and chronic non-thyroidal illnesses, it became evident that body temperature may be one parameter associated with changes in serum T3 levels. Forty-nine hospitalized, euthyroid patients with hyperpyrexia caused by various non-thyroidal illnesses were studied. The levels of serum T3 were found to decrease gradually with increasing body temperature. T3 was already below the normal level +/- 2 S.D. at a body temperature of around 38 degrees C. Such low T3 levels as were seen at temperatures of above 40 degrees C are observed in thyroid patients only during severe hypothyroidism. The levels of T4 and TSH remained unchanged and within the normal range regardless of body temperature. The levels of reverse-T3 in the sera analyzed were found to be unchanged in some cases, while in others they paralleled body temperature. It is concluded that the body temperature must be taken into consideration when studying the serum levels of T3.

Serum thyroid hormone levels in patients on thyroxine replacement therapy.

Serum thyroid hormone levels in patients on thyroxine replacement therapy.