Levothyroxine in Women with Thyroid Peroxidase Antibodies before Conception.

BACKGROUND: Thyroid peroxidase antibodies are associated with an increased risk of miscarriage and preterm birth, even when thyroid function is normal. Small trials indicate that the use of levothyroxine could reduce the incidence of such adverse outcomes. METHODS: We conducted a double-blind, placebo-controlled trial to investigate whether levothyroxine treatment would increase live-birth rates among euthyroid women who had thyroid peroxidase antibodies and a history of miscarriage or infertility. A total of 19,585 women from 49 hospitals in the United Kingdom underwent testing for thyroid peroxidase antibodies and thyroid function. We randomly assigned 952 women to receive either 50 µg once daily of levothyroxine (476 women) or placebo (476 women) before conception through the end of pregnancy. The primary outcome was live birth after at least 34 weeks of gestation. RESULTS: The follow-up rate for the primary outcome was 98.7% (940 of 952 women). A total of 266 of 470 women in the levothyroxine group (56.6%) and 274 of 470 women in the placebo group (58.3%) became pregnant. The live-birth rate was 37.4% (176 of 470 women) in the levothyroxine group and 37.9% (178 of 470 women) in the placebo group (relative risk, 0.97; 95% confidence interval [CI], 0.83 to 1.14, P = 0.74; absolute difference, -0.4 percentage points; 95% CI, -6.6 to 5.8). There were no significant between-group differences in other pregnancy outcomes, including pregnancy loss or preterm birth, or in neonatal outcomes. Serious adverse events occurred in 5.9% of women in the levothyroxine group and 3.8% in the placebo group (P = 0.14). CONCLUSIONS: The use of levothyroxine in euthyroid women with thyroid peroxidase antibodies did not result in a higher rate of live births than placebo. (Funded by the United Kingdom National Institute for Health Research; TABLET Current Controlled Trials number, ISRCTN15948785.).

Association of maternal levothyroxine use during pregnancy with offspring birth and neurodevelopmental outcomes: a population-based cohort study.

BACKGROUND: The influence of maternal levothyroxine treatment during pregnancy remains unclear. This study aimed to evaluate the associations of maternal levothyroxine treatment during pregnancy with the birth and neurodevelopmental outcomes in offspring. METHODS: This population-based cohort study was conducted among pregnant women using the Hong Kong Clinical Data Analysis and Reporting System. Mother-child pairs in Hong Kong from 2001 to 2015 were included and children were followed up till 2020. We defined the exposure group as mothers who were exposed to levothyroxine during pregnancy. Preterm birth and small for gestational age (SGA) were included as birth outcomes. Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) were included as neurodevelopmental outcomes. Odds ratios (OR) or hazard ratios (HRs) with a 95% confidence interval (CI) were evaluated to assess the association of gestational levothyroxine use with offspring birth and neurodevelopmental outcomes respectively, using propensity score fine-stratification weighting and a Cox proportional hazards regression model. RESULTS: Among 422,156 mother-child pairs, 2125 children were born from mothers exposed to levothyroxine during pregnancy. A significantly increased risk of preterm birth was observed in children with maternal levothyroxine exposure during pregnancy, when compared to mothers who had no history of thyroid-related diagnoses or prescriptions (weighted OR [wOR]: 1.22, 95% CI: 1.07, 1.39). Similarly, an increased risk of preterm birth was found among children of gestational levothyroxine users, when compared to children of mothers who had used levothyroxine before but stopped during pregnancy (wOR: 2.16, 95% CI: 1.09, 4.25). Sensitivity analysis, by excluding mothers exposed to psychotropic or antiepileptic medications before or during pregnancy, also indicated a similar increased risk of preterm birth regarding the gestational use of levothyroxine (wOR: 1.26, 95% CI: 1.10, 1.45). No significant association was observed for the risk of SGA, ADHD, and ASD. CONCLUSIONS: There is no evidence that gestational use of levothyroxine is associated with SGA, ADHD, or ASD in offspring. Gestational levothyroxine treatment is associated with a higher risk of preterm birth. Such risk might be confounded by the underlying maternal thyroid disease itself, however, we cannot completely exclude the possible effect of gestational L-T4 treatment on offspring preterm birth. Our findings provided support to the current guidelines on the cautious use of levothyroxine treatment during pregnancy.

Oxcarbazepine was associated with risks of newly developed hypothyroxinaemia and impaired central set point of thyroid homeostasis in schizophrenia patients.

AIMS: Hypothyroxinaemia might be easily ignored, because attention is typically paid to individuals with elevated thyroid stimulating hormone (TSH). In this study, we aimed to evaluate the association of oxcarbazepine use as adjuvant for treatment of schizophrenia with hypothyroxinaemia and central set point of thyroid homeostasis. METHODS: This retrospective cohort study was conducted in the Second Affiliated Hospital of Xinxiang Medical University. Inpatients with a diagnosis of schizophrenia admitted between January 2016 and October 2019 with normal thyroid function at admission were included. Oxcarbazepine use was the exposure measure. Newly developed hypothyroxinaemia was the primary outcome measure and parameters of thyroid homeostasis central set point as measured by TSH index and thyroid feedback quantile-based index (TFQI) were the secondary outcome measures. RESULTS: In total, 1207 eligible patients were included. The occurrence of hypothyroxinaemia in patients who received oxcarbazepine was higher (35/107, 32.7%) than in those patients who did not (152/1099, 13.8%), with adjusted relative risk of 2.24 and 95% confidence interval of 1.57 and 3.17. Oxcarbazepine use was associated with greater reduction in TSH index (adjusted ß -0.33 and 95% confidence interval -0.48, -0.19) and TFQI (adjusted ß -0.24 and 95% confidence interval -0.31, -0.16). CONCLUSION: Oxcarbazepine use was independently associated with increased risk of developing hypothyroxinaemia, and greater reduction in TSH index and TFQI, suggesting that impaired central set point of thyroid homeostasis might be involved in the mechanism of oxcarbazepine-induced hypothyroxinaemia.

Cardiovascular protective effects of PPARγ agonists in hypothyroid rats: protection against oxidative stress.

Hypothyroidism disturbs redox homeostasis and takes part in cardiovascular system dysfunction. Considering antioxidant and cardio-protective effects of PPAR-γ agonists including pioglitazone (POG) and rosiglitazone (RSG), the present study was aimed to determine the effect of POG or RSG on oxidants and antioxidants indexes in the heart and aorta tissues of Propylthiouracil (PTU)-induced hypothyroid rats. MATERIALS AND METHODS: The animals were divided into six groups: (1) Control; (2) propylthiouracil (PTU), (3) PTU-POG 10, (4) PTU-POG 20, (5) PTU-RSG 2, and (6) PTU-RSG 4. Hypothyroidism was induced in rats by giving 0.05% propylthiouracil (PTU) in drinking water for 42 days. The rats of PTU-POG 10 and PTU-POG 20 groups received 10 and 20 mg/kg POG, respectively, besides PTU, and the rats of PTU-RSG 2 and PTU-RSG 4 groups received 2 and 4 mg/kg RSG, respectively, besides PTU. The animals were sacrificed, and the serum of the rats was collected to measure thyroxine level. The heart and aorta tissues were also removed for the measurement of biochemical oxidative stress markers. RESULTS: Hypothyroidism was induced by PTU administration, which was indicated by lower serum thyroxine levels. Hypothyroidism also was accompanied by a decrease of catalase (CAT), superoxide dismutase (SOD) activities, and thiol concentration in the heart and aorta tissues while increased level of malondialdehyde (MDA). Interestingly, administration of POG or RSG dramatically reduced oxidative damage in the heart and aorta, as reflected by a decrease in MDA and increased activities of SOD, CAT, and thiol content. CONCLUSION: The results of this study showed that administration of POG or RSG decreased oxidative damage in the heart and aorta tissues induced by hypothyroidism in rats.

Possible protective role of L-thyroxin on the parotid gland of adult male albino rat in carbimazole induced hypothyroidism: histological, histomorphometry, and ultrastructural study.

BACKGROUND: Thyroid disorders are among the most common metabolic disorders worldwide. Thyroid dysfunction affects salivary glands function, causing hyposalivation. It also provokes physiological and histological changes in parotid, submandibular, and in particular the sublingual gland. THE AIM OF THIS WORK: The aim of this work was to clarify the histological and ultrastructural changes that occur in the parotid gland following carbimazole-induced hypothyroidism in adult male albino rats. The study also aims to investigate the possible protective role of L-thyroxin supplementation on the rat parotid glands after long and short duration of hypothyroidism. MATERIAL AND METHODS: Fifty-five adult male albino rats of Sprague Dawley strain; were divided into four groups and eleven subgroups, five rats each. G І received nothing. G П given normal saline orally daily. G Ш (medical Hypothyroidism, short duration - long duration - recovery group) given Carbimazole orally by gastric tube in a dose of 0.05 mg/kg daily for 3,6 successive weeks for group (a, b) and for 6 successive weeks then were left without any medication for another 3 weeks in recovery group c. G IV-b, c (L-Thyroxine supplemented group, short duration-long duration) given Carbimazole orally daily for 3,6 successive weeks then L-thyroxine was given orally in a dose of (10 µg/100 g/B.W) daily for another 3 successive weeks. Animals were sacrificed 24 hours after the last dose of Carbimazole in G III-a, b and 3 weeks after stoppage the drug in G III-c. Animals were sacrificed 24 hours after the last dose of L- Thyroxine in G IV-b, c. The parotid specimens were processed for histopathological examination by light and electron microscopy. The medically induced Hypothyroidism resulted in significant parotid gland damage which was more obvious with longer duration; as follow: a) most of the acini had irregular outlines and were widely separated with narrow lumen and cytoplasmic vacuoles. b) some acinar cells contained ill defined, irregular, pyknotic or hyperchromatic nuclei. c)Vascular changes: dilated and engorged with blood. d) the interlobular and striated ducts appeared disrupted and dilated. e) extravasated blood with cellular infiltration were seen in the interstitial space. IN CONCLUSION: Thyroid hormones (THs) had a significant effect in protection of parotid gland against damage induced by carbimazole, as it preserved the normal histological architecture of the parotid gland. This beneficial effect of THs was mostly related to its antioxidant properties. The expression of BCL-2 has certain regularity in apoptosis after drug administration. Regulation of glandular atrophy and apoptosis are closely related. The molecular mechanism of the apoptosis of the gland is not clear, and further study is needed in the future.

Association between levothyroxine replacement therapy and osteoporosis in Riyadh, Saudi Arabia: a matched case-control study.

Hypothyroidism is a common health problem among elder women. However, conflicting results were observed regarding the association between levothyroxine treatment and osteoporosis risk. Therefore, the current study aimed to evaluate the effect of levothyroxine replacement therapy on osteoporosis risk in the Saudi population. This study was a matched case-control study conducted from June to August 2020. Data were extracted from the electronic medical records and included sociodemographic, clinical characteristics, comorbid conditions, levothyroxine replacement therapy dose, duration, concomitant therapy, and bone mineral density. Cases were matched with controls (1:1 basis) by age; the study included 256 cases and 256 controls. In the multivariate conditional logistic regression analysis, thyroxine use was independently associated with an increased likelihood of osteoporosis. Therefore levothyroxine use in elderly females was associated with an increased risk of osteoporosis, and hence, clinicians must be aware of the levothyroxine replacement therapy outcomes in postmenopausal females at risk of osteoporosis.

AMIODARONE AND THYROID DYSFUNCTION.

Thyroid gland has a key role in maintaining the body homeostasis. Thyroxine is the main hormone secreted from the thyroid gland, its effect being predominantly achieved after the intracellular conversion of thyroxine to triiodothyronine, which exhibits a higher affinity for the receptor complex, thus modifying gene expression of the target cells. Amiodarone is one of the most commonly used antiarrhythmics in the treatment of a broad spectrum of arrhythmias, usually tachyarrhythmias. Amiodarone contains a large proportion of iodine, which is, in addition to the intrinsic effect of the medication, the basis of the impact on thyroid function. It is believed that 15%-20% of patients treated with amiodarone develop some form of thyroid dysfunction. Amiodarone may cause amiodarone-induced hypothyroidism (AIH) or amiodarone-induced thyrotoxicosis (AIT). AIT is usually developed in the areas with too low uptake of iodine, while AIH is developed in the areas where there is a sufficient iodine uptake. Type 1 AIT is more common among patients with an underlying thyroid pathology, such as nodular goiter or Graves' (Basedow's) disease, while type 2 mostly develops in a previously healthy thyroid. AIH is more common in patients with previously diagnosed Hashimoto's thyroiditis. Combined types of the diseases have also been described. Patients treated with amiodarone should be monitored regularly, including laboratory testing and clinical examinations, to early detect any deviations in the functioning of the thyroid gland. Supplementary levothyroxine therapy is the basis of AIH treatment. In such cases, amiodarone therapy quite often need not be discontinued. Type 1 AIT is treated with thyrostatic agents, like any other type of thyrotoxicosis. If possible, the underlying amiodarone therapy should be discontinued. In contrast to type 1 AIT, the basic pathophysiological substrate of which is the increased synthesis and release of thyroid hormones, the basis of type 2 AIT is destructive thyroiditis caused by amiodarone, desethylamiodarone as its main metabolite, and an increased iodine uptake. Glucocorticoid therapy is the basis of treatment for this type of disease.

Risk of cancer in long-term levothyroxine users: Retrospective population-based study.

Levothyroxine is a widely prescribed medication for the treatment of an underactive thyroid. The relationship between levothyroxine use and cancer risk is largely underdetermined. To investigate the magnitude of the possible association between levothyroxine use and cancer risk, this retrospective case-control study was conducted using Taiwan's Health and Welfare Data Science Center database. Cases were defined as all patients who were aged ≥20 years and had a first-time diagnosis for cancer at any site for the period between 2001 and 2011. Multivariable conditional logistic regression models were used to calculate an adjusted odds ratio (AOR) to reduce potential confounding factors. A total of 601 733 cases and 2 406 932 controls were included in the current study. Levothyroxine users showed a 50% higher risk of cancer at any site (AOR: 1.50, 95% CI: 1.46-1.54; P < .0001) compared with non-users. Significant increased risks were also observed for brain cancer (AOR: 1.90, 95% CI: 1.48-2.44; P < .0001), skin cancer (AOR: 1.42, 95% CI: 1.17-1.72; P < .0001), pancreatic cancer (AOR: 1.27, 95% CI: 1.01-1.60; P = .03), and female breast cancer (AOR: 1.24, 95% CI: 1.15-1.33; P < .0001). Our study results showed that levothyroxine use was significantly associated with an increased risk of cancer, particularly brain, skin, pancreatic, and female breast cancers. Levothyroxine remains a highly effective therapy for hypothyroidism; therefore, physicians should carefully consider levothyroxine therapy and monitor patients' condition to avoid negative outcomes. Additional studies are needed to confirm these findings and to evaluate the potential biological mechanisms.

Pharmacokinetics of cannabidiol in children with refractory epileptic encephalopathy.

Growing interest in the clinical use of cannabidiol (CBD) as adjuvant therapy for pediatric refractory epileptic encephalopathy emphasizes the need for drug treatment optimization. The aim of this study was to characterize the pharmacokinetics of CBD in pediatric patients with refractory epileptic encephalopathy receiving an oil-based oral solution. To evaluate CBD concentrations, six serial blood samples per patient were collected after the morning dose of CBD, at least 21 days after the beginning of treatment. Twelve patients who received a median (range) dose of 12.2 (5.3-19.4) mg/kg/d (twice daily) were included in the analysis. Median (range) CBD time to maximum plasma concentration, maximum plasma concentration, and area under the concentration versus time curve up to 6 hours after dosing were 3.2 hours (1.9-6.2), 49.6 ng/mL (14.4-302.0), and 226.3 ng ⋅ h/mL (70.5-861.3), respectively. CBD systemic exposure parameters were in the lower range of previous reports in pediatric patients receiving doses in a similar range. Most of our patients (83%) showed little CBD plasma level fluctuation during a dosing interval, comparable to that encountered after oral administration of an extended release drug delivery system. CDB administration was generally safe and well tolerated, and a novel levothyroxine-CBD interaction was recorded. Similar to other studies, large interindividual variability in CBD exposure was observed, encouraging the use of CBD therapeutic drug monitoring.

Effects of Chronic Suppression or Oversuppression of Thyroid-Stimulating Hormone on Psychological Symptoms and Sleep Quality in Patients with Differentiated Thyroid Cancer.

In differentiated thyroid cancer (DTC), the standard treatment includes total thyroidectomy and lifetime levothyroxine (LT4) replacement. However, long-term exogenous LT4 has become controversial due to the adverse effects of oversuppression. The study included 191 patients (aged 18-76 years) with a prospective diagnosis of non-metastatic DTC and 79 healthy individuals. The patients with DTC were stratified into three groups according to their TSH levels: suppressed thyrotropin if TSH was below 0.1 µIU/ml, mildly suppressed thyrotropin if TSH was between 0.11 and 0.49 µIU/ml, and low-normal thyrotropin if THS was between 0.5 and 2 µIU/ml. The Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), Anxiety Sensitivity Index (ASI), Short Symptom Inventory (SSI), and Pittsburgh Sleep Quality Index (PSQI) were administered to all participants. It was found that the BDI, BAI, SSI and PSQI scores were worse in patients with DTC (p=0.024, p=0.014, p=0.012, and p=0.001, respectively). According to theTSH levels, the mean ASI was found to be higher in the suppressed and mildly suppressed thyrotropin groups (19±14.4 vs. 10.6±11.1; 16.4±14.9 vs. 10.6±11.1, p=0.024, respectively), the mean SSI was found higher in the suppressed group (61.0±55.5 vs. 35.1±37.0, p=0.046), and the mean PSQI was higher in all three groups (7.94±3.97 vs. 5.35±4.13; 7.21±4.59 vs. 5.35±4.13; 7.13±4.62 vs. 5.35±4.13, p=0.006) when compared with the controls. No significant difference was found between the groups. A positive correlation was detected in the duration of LT4 use and BDI and SSI, and a weak, negative correlation was detected between TSH levels and ASI and PSQI. Based on our study, it was found that depression, anxiety disorders, and sleep problems were more prevalent in patients with DTC, being more prominent in the suppressed TSH group. These results were inversely correlated with TSH values and positively correlated with the duration of LT4 use. Unnecessary LT4 oversuppression should be avoided in patients with DTC.

Trabecular bone score in women with differentiated thyroid cancer on long-term TSH-suppressive therapy.

INTRODUCTION: Thyrotropin stimulating hormone (TSH) suppression in patients with differentiated thyroid cancer (DTC) aims to decrease the growth and proliferation of thyroid cancer cells. However, the effect of TSH-suppressive therapy on bone microarchitecture remains undefined. METHODS: Cross-sectional study including 43 women with DTC undergoing TSH-suppressive therapy (sTSH) compared to 20 women also on levothyroxine (LT4) therapy but with TSH in the low-normal range (nTSH) since the thyroid surgery. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DXA), and trabecular bone score (TBS) was evaluated using the TBS iNsigth software. Fracture risk assessed by FRAX, with and without TBS, was calculated. The relationship between suppressive therapy-related parameters and bone parameters was investigated. RESULTS: The TBS mean values were not significantly different in the sTSH and nTSH groups (1.273 ± 0.12 vs 1.307 ± 0.14, p = 0.7197). In both groups, postmenopausal women had degraded microarchitecture (TBS 1.216 ± 0.11 vs 1.213 ± 0.09, p = 0.9333), while premenopausal women had normal microarchitecture (1.328 ± 0.11 vs 1.401 ± 0.12, p = 0.195). The percentage of all postmenopausal women with degraded TBS was 54.7%, while the percentage of osteoporosis diagnoses was 16.1%. The TBS-adjusted FRAX-probability of fracture was similar in sTSH and nTSH groups. Body mass index (BMI) and menopausal status were the only variables associated with TBS and BMD. CONCLUSION: Trabecular microarchitecture assessed by TBS was similar between women on long-term suppressive therapy in DTC and those on LT4 replacement therapy aiming at a TSH level within the low-normal reference range. Low TBS values were observed in postmenopausal women of both groups, suggesting that not only suppressed TSH levels but also a low-normal TSH is associated with deteriorated bone microarchitecture in postmenopausal women following total thyroidectomy.

Hypothyroidism: Diagnosis and Treatment.

Clinical hypothyroidism affects one in 300 people in the United States, with a higher prevalence among female and older patients. Symptoms range from minimal to life-threatening (myxedema coma); more common symptoms include cold intolerance, fatigue, weight gain, dry skin, constipation, and voice changes. The signs and symptoms that suggest thyroid dysfunction are nonspecific and nondiagnostic, especially early in disease presentation; therefore, a diagnosis is based on blood levels of thyroid-stimulating hormone and free thyroxine. There is no evidence that population screening is beneficial. Symptom relief and normalized thyroid-stimulating hormone levels are achieved with levothyroxine replacement therapy, started at 1.5 to 1.8 mcg per kg per day. Adding triiodothyronine is not recommended, even in patients with persistent symptoms and normal levels of thyroid-stimulating hormone. Patients older than 60 years or with known or suspected ischemic heart disease should start at a lower dosage of levothyroxine (12.5 to 50 mcg per day). Women with hypothyroidism who become pregnant should increase their weekly dosage by 30% up to nine doses per week (i.e., take one extra dose twice per week), followed by monthly evaluation and management. Patients with persistent symptoms after adequate levothyroxine dosing should be reassessed for other causes or the need for referral. Early recognition of myxedema coma and appropriate treatment is essential. Most patients with subclinical hypothyroidism do not benefit from treatment unless the thyroid-stimulating hormone level is greater than 10 mIU per L or the thyroid peroxidase antibody is elevated.

[Effect of levothyroxine treatment on pregnancy outcomes in euthyroid women with thyroid autoantibody positive: a Meta-analysis].

Objective: To conduct a systematic review of the association of levothyroxine treatment with pregnancy outcomes in euthyroid women who are thyroid autoantibody positive. Methods: Medline, Excerpta Medica (EMBASE), Cochrane Library, China National Knowledge Infrastructure (CNKI), China Biology Medicine (CBM), Wanfang data and VIP database were searched from inception until Jan. 28, 2020. All published randomized controlled trials assessing the association of levothyroxine treatment with pregnancy outcomes in euthyroid women with thyroid autoantibody-positive were included. STATA 11.0 and RevMan 5.3 softwares were used to perform this Meta-analysis. Results: A total of 6 studies met the inclusion criteria, with 2 188 women randomized. Meta-analysis showed that there was no significantly association between miscarriage (OR=0.85, 95%CI: 0.65-1.11, P=0.234) and preterm birth (OR=0.79, 95%CI: 0.54-1.16, P=0.224) with levothyroxine treatment. Conclusions: Levothyroxine therapy could not reduce the risk of miscarriage and preterm birth in euthyroid women with thyroid autoantibody-positive. Therefore, levothyroxine should be used with caution for these pregnant women.

Thyroid Hormone Therapy for Older Adults with Subclinical Hypothyroidism.

BACKGROUND: The use of levothyroxine to treat subclinical hypothyroidism is controversial. We aimed to determine whether levothyroxine provided clinical benefits in older persons with this condition. METHODS: We conducted a double-blind, randomized, placebo-controlled, parallel-group trial involving 737 adults who were at least 65 years of age and who had persisting subclinical hypothyroidism (thyrotropin level, 4.60 to 19.99 mIU per liter; free thyroxine level within the reference range). A total of 368 patients were assigned to receive levothyroxine (at a starting dose of 50 µg daily, or 25 µg if the body weight was <50 kg or the patient had coronary heart disease), with dose adjustment according to the thyrotropin level; 369 patients were assigned to receive placebo with mock dose adjustment. The two primary outcomes were the change in the Hypothyroid Symptoms score and Tiredness score on a thyroid-related quality-of-life questionnaire at 1 year (range of each scale is 0 to 100, with higher scores indicating more symptoms or tiredness, respectively; minimum clinically important difference, 9 points). RESULTS: The mean age of the patients was 74.4 years, and 396 patients (53.7%) were women. The mean (±SD) thyrotropin level was 6.40±2.01 mIU per liter at baseline; at 1 year, this level had decreased to 5.48 mIU per liter in the placebo group, as compared with 3.63 mIU per liter in the levothyroxine group (P<0.001), at a median dose of 50 µg. We found no differences in the mean change at 1 year in the Hypothyroid Symptoms score (0.2±15.3 in the placebo group and 0.2±14.4 in the levothyroxine group; between-group difference, 0.0; 95% confidence interval [CI], -2.0 to 2.1) or the Tiredness score (3.2±17.7 and 3.8±18.4, respectively; between-group difference, 0.4; 95% CI, -2.1 to 2.9). No beneficial effects of levothyroxine were seen on secondary-outcome measures. There was no significant excess of serious adverse events prespecified as being of special interest. CONCLUSIONS: Levothyroxine provided no apparent benefits in older persons with subclinical hypothyroidism. (Funded by European Union FP7 and others; TRUST ClinicalTrials.gov number, NCT01660126 .).

Topical L-thyroxine: The Cinderella among hormones waiting to dance on the floor of dermatological therapy?

Topical hormone therapy with natural or synthetic ligands of nuclear hormone receptors such as glucocorticoids, vitamin D analogues and retinoids has a long and highly successful tradition in dermatology. Yet the dermatological potential of thyroid hormone receptor (TR) agonists has been widely ignored, despite abundant clinical, cell and molecular biology, mouse in vivo, and human skin and hair follicle organ culture data documenting a role of TR-mediated signalling in skin physiology and pathology. Here, we review this evidence, with emphasis on wound healing and hair growth, and specifically highlight the therapeutic potential of repurposing topical L-thyroxine (T4) for selected applications in future dermatological therapy. We underscore the known systemic safety and efficacy profile of T4 in clinical medicine, and the well-documented impact of thyroid hormones on, for example, human epidermal and hair follicle physiology, hair follicle epithelial stem cells and pigmentation, keratin expression, mitochondrial energy metabolism and wound healing. On this background, we argue that short-term topical T4 treatment deserves careful further preclinical and clinical exploration for repurposing as a low-cost, effective and widely available dermatotherapeutic, namely in the management of skin ulcers and telogen effluvium, and that its predictable adverse effects are well-manageable.

Ameliorative effect of Aloe gel against L-T4-induced hyperthyroidism via suppression of thyrotropin receptors, inflammation and oxidative stress.

Untreated hyperthyroidism may develop serious complications. This attempt was made to investigate the potential of Aloe vera gel in regulating experimentally induced hyperthyroidism in rats. Female Wistar rats were made hyperthyroid with L-thyroxine (L-T4) at 0.5 mg/kg/day, i.p. for 14 days and the effects of Aloe vera methanolic fraction (AVMF) (50 or 500 mg/kg/day, p.o.,) and a conventional antithyroid drug propylthiouracil (PTU) (10 mg/kg, i.p.) for 30 days were studied in those hyperthyroid rats. At the end, alterations in serum thyroid hormones and thyroid stimulating hormone (TSH); hepatic 5'mono-deiodinase-1(5'D1) activity, oxidative stress markers and antioxidants; serum inflammatory cytokines and the expression of thyrotropin receptor in thyroid gland were evaluated in all experimental animals. Hyperthyroid condition was confirmed by an increase in thyroid hormone levels and hepatic 5'D-1 activity with a decrease in TSH. However, either AVMF or PTU treatment in hyperthyroid rats decreased the levels of thyroid hormones and 5'D1 activity. AVMF administration in T4-induced rats also decreased the oxidative stress markers such as thiobarbituric acid reactive substances and lipid hydroperoxides and increased the antioxidant levels in liver tissues. Levels of liver marker enzymes, cytokines and different lipids were decreased in T4-induced AVMF treated rats. Further, a down regulation in the TSHR expression in thyroid was observed in AVMF or PTU treated groups. All these thyroid inhibiting effects were supported by an improvement in thyroid histology in hyperthyroid rats. It appears, about 15 compounds, as evidenced by LC-MS/MS study, mostly phenolics are involved in this anti-thyroid effects of the test compound.

Self-Reported Allergy to Thyroid Replacement Therapy: A Multicenter Retrospective Chart Review.

OBJECTIVE: To determine patterns of adverse drug reactions (ADRs), including immediate drug hypersensitivity reactions (DHRs) and predictable ADRs, to thyroid replacement therapy (TRT). TRT is the treatment of choice for hypothyroidism. Levothyroxine (LT4) is among the most commonly prescribed medications in the United States, with over 70 million prescriptions annually. Documented immediate DHRs to TRT are rare, with only a few case reports. METHODS: An 11-year (2008-2018) retrospective medical chart review of identified patients with self-reported allergy to TRT. ADRs to TRT were divided into immediate DHRs and predictable ADRs. RESULTS: A total of 466 patients were included in our study. We found an overall incidence of ADRs to TRT of 0.3%. Median age was 61.2 years; 85.8% were women, and 94.4% were Caucasian. The principal indication for TRT was autoimmune hypothyroidism (73.6%), followed by postsurgical hypothyroidism (17.4%) and subclinical hypothyroidism (6.7%). Predictable ADR manifestations to TRT were reported more commonly than DHR manifestations (57.5% vs. 42.5%, respectively). The most frequently reported of the former were palpitations (16.4%), nausea/vomiting (9.3%), and tremor (6.3%), while rash (23.8%), hives (9.5%), and pruritus (7.1%) were the most common regarding the latter. Fifty-six percent of the patients with an ADR to TRT tolerated an alternative TRT presentation. CONCLUSION: In our cohort, the majority of self-reported allergies to TRT were due to predictable ADRs rather than an immediate DHR. ABBREVIATIONS: ADR = adverse drug reaction; DHR = drug hypersensitivity reaction; FDA = Food and Drug Administration; LT3 = liothyronine; LT4 = levothyroxine; SCAR = severe cutaneous adverse drug reaction; TRT = thyroid replacement therapy.

Levothyroxine treatment and incident dementia in adults with atrial fibrillation.

OBJECTIVE: Levothyroxine treatment is common among older adults as is atrial fibrillation (AF), yet less is known about its potential effects on the development of dementia. METHODS: The study population included all adults with diagnosed AF (n = 156,104) aged ≥ 45 years in Sweden without an earlier recorded diagnosis of dementia. Individuals with a dispensed prescription of levothyroxine on two or more occasions between July 1 2005 and December 31 2006 in Sweden were considered exposed (n = 12,978; 8.3%), and were compared to all other patients with AF without this treatment. Cox regression with hazard ratios (HRs) and 95% confidence interval (95% CI), with outcome defined as dementia of all causes between January 1, 2007 and December 31, 2015, was used in the analysis. Adjustments were made for socio-demographic factors (age, immigration status, marital status, educational level, neighborhood socioeconomic status), co-morbidity (cardiovascular disease, obesity, diabetes, COPD, depression, anxiety and alcohol related diagnoses), and cardiovascular medications. RESULTS: During follow-up, a total of 9054 patients with AF were diagnosed with dementia (5.8%). We found no significant association of levothyroxine treatment and incident dementia, fully adjusted HR 1.03 (95% CI 0.96-1.11), neither among men and women, nor in different age-groups or subgroups of dementia. CONCLUSION: We found no significant association of levothyroxine treatment and incident dementia among patients with AF, which contrasts some earlier findings.

Oral Manifestations of Commonly Prescribed Drugs.

Drugs are being prescribed with more frequency and in higher quantities. A serious adverse drug event from prescribed medications constitutes 2.4% to 16.2% of all hospital admissions. Many of the adverse drug events present intraorally or periorally in isolation or as a clinical symptom of a systemic effect. Clinical recognition and treatment of adverse drug events are important to increase patient adherence, manage drug therapy, or detect early signs of potentially serious outcomes. Oral manifestations of commonly prescribed medications include gingival enlargement, oral hyperpigmentation, oral hypersensitivity reaction, medication-related osteonecrosis, xerostomia, and other oral or perioral conditions. To prevent dose-dependent adverse drug reactions, physicians should prescribe medications judiciously using the lowest effective dose with minimal duration. Alternatively, for oral hypersensitivity reactions that are not dose dependent, quick recognition of clinical symptoms associated with time-dependent drug onset can allow for immediate discontinuation of the medication without discontinuation of other medications. Physicians can manage oral adverse drug events in the office through oral hygiene instructions for gingival enlargement, medication discontinuation for oral pigmentation, and prescription of higher fluoride toothpastes for xerostomia.

Effect of Levothyroxine on Left Ventricular Ejection Fraction in Patients With Subclinical Hypothyroidism and Acute Myocardial Infarction: A Randomized Clinical Trial.

Importance: Thyroid hormones play a key role in modulating myocardial contractility. Subclinical hypothyroidism in patients with acute myocardial infarction is associated with poor prognosis. Objective: To evaluate the effect of levothyroxine treatment on left ventricular function in patients with acute myocardial infarction and subclinical hypothyroidism. Design, Setting, and Participants: A double-blind, randomized clinical trial conducted in 6 hospitals in the United Kingdom. Patients with acute myocardial infarction including ST-segment elevation and non-ST-segment elevation were recruited between February 2015 and December 2016, with the last participant being followed up in December 2017. Interventions: Levothyroxine treatment (n = 46) commencing at 25 µg titrated to aim for serum thyrotropin levels between 0.4 and 2.5 mU/L or identical placebo (n = 49), both provided in capsule form, once daily for 52 weeks. Main Outcomes and Measures: The primary outcome measure was left ventricular ejection fraction at 52 weeks, assessed by magnetic resonance imaging, adjusted for age, sex, type of acute myocardial infarction, affected coronary artery territory, and baseline left ventricular ejection fraction. Secondary measures were left ventricular volumes, infarct size (assessed in a subgroup [n = 60]), adverse events, and patient-reported outcome measures of health status, health-related quality of life, and depression. Results: Among the 95 participants randomized, the mean (SD) age was 63.5 (9.5) years, 72 (76.6%) were men, and 65 (69.1%) had ST-segment elevation myocardial infarction. The median serum thyrotropin level was 5.7 mU/L (interquartile range, 4.8-7.3 mU/L) and the mean (SD) free thyroxine level was 1.14 (0.16) ng/dL. The primary outcome measurements at 52 weeks were available in 85 patients (89.5%). The mean left ventricular ejection fraction at baseline and at 52 weeks was 51.3% and 53.8%, respectively, in the levothyroxine group compared with 54.0% and 56.1%, respectively, in the placebo group (adjusted difference in groups, 0.76% [95% CI, -0.93% to 2.46%]; P = .37). None of the 6 secondary outcomes showed a significant difference between the levothyroxine and placebo treatment groups. There were 15 (33.3%) and 18 (36.7%) cardiovascular adverse events in the levothyroxine and placebo groups, respectively. Conclusions and Relevance: In this preliminary study involving patients with subclinical hypothyroidism and acute myocardial infarction, treatment with levothyroxine, compared with placebo, did not significantly improve left ventricular ejection fraction after 52 weeks. These findings do not support treatment of subclinical hypothyroidism in patients with acute myocardial infarction. Trial Registration: isrctn.org Identifier: http://www.isrctn.com/ISRCTN52505169.