Thyroid hormone misuse and abuse

Understanding the Roles of Selenium on Thyroid Hormone-Induced Thermogenesis in Adipose Tissue

Brown adipose tissue (BAT) and white adipose tissue (WAT) are known to regulate lipid metabolism. A lower amount of BAT compared to WAT, along with adipose tissue dysfunction, can result in obesity. Studies have shown that selenium supplementation protects against adipocyte dysfunction, decreases WAT triglycerides, and increases BAT triiodothyronine (T3). In this review, we discuss the relationship between selenium and lipid metabolism regulation through selenoprotein deiodinases and the role of deiodinases and thyroid hormones in the induction of adipose tissue thermogenesis. Upon 22 studies included in our review, we found that studies investigating the relationship between selenium and deiodinases demonstrated that selenium supplementation affects the iodothyronine deiodinase 2 (DIO2) protein and the expression of its associated gene, DIO2, proportionally. However, its effect on DIO1 is inconsistent while its effect on DIO3 activity is not detected. Studies have shown that the activity of deiodinases especially DIO2 protein and DIO2 gene expression is increased along with other browning markers upon white adipose tissue browning induction. Studies showed that thermogenesis is stimulated by the thyroid hormone T3 as its activity is correlated to the expression of other thermogenesis markers. A proposed mechanism of thermogenesis induction in selenium supplementation is by autophagy control. However, more studies are needed to establish the role of T3 and autophagy in adipose tissue thermogenesis, especially, since some studies have shown that thermogenesis can function even when T3 activity is lacking and studies related to autophagy in adipose tissue thermogenesis have contradictory results.

Medical and Psychiatric Features of Patients Hospitalized for Severe Restrictive Eating Disorders: Analysis of 545 Consecutive Patients with Severe Anorexia Nervosa or Avoidant/Restrictive Food Intake Disorder

BACKGROUND

People with severe eating and feeding disorders regularly require hospitalization due to complications inherent to their disease, though formal training regarding this care is limited.

METHODS

This retrospective study included 545 patients with severe anorexia nervosa (AN) or avoidant restrictive food intake disorder hospitalized in a medical stabilization unit between 2018 and 2021. Biometrics were obtained throughout hospitalization. Nutrition was increased until patients were gaining 0.2 kg/day.

RESULTS

Average admission body mass index was 13 kg/m2 with diagnoses of 46% AN-R (restricting), 39% AN-BP (binge-purge), and 15% avoidant restrictive food intake disorder. Average daily Kcals by discharge were 3343 for females and 3962 for males; 26% required nasogastric feeding. Hypoglycemia was common until day 7, correlated with elevated liver function tests and low prealbumin. Liver function tests were abnormal in 31% of patients. Refeeding hypophosphatemia developed in 26% of patients starting day 2 and was associated with lower body mass index. Hypokalemia appeared on admission among 39%, twice as common in patients diagnosed with AN-BP. Initial electrocardiograms were abnormal in 50% of patients, usually sinus bradycardia. Average QTc was normal, but only 14% prolonged. Bone density testing revealed 70% osteoporosis. History of suicide attempts were present in 19%, while 76% and 50% presented with anxiety and depressive disorders, respectively.

CONCLUSIONS

Given the inextricability of medical complications from severe eating and feeding disorders, familiarity among consult-liaison psychiatrists with the prevalence of frequently observed abnormal findings can inform consultation, prevent adverse events, prevent unnecessary intervention, and facilitate weight restoration and medical stabilization.

Prescription medication use during pregnancy in the United States from 2011 to 2020: trends and safety evidence

BACKGROUND

Medication use during pregnancy has increased in the United States despite the lack of safety data for many medications.

OBJECTIVE

This study aimed to inform research priorities by examining trends in medication use during pregnancy and identifying gaps in safety information on the most commonly prescribed medications.

STUDY DESIGN

We identified population-based cohorts of commercially (MarketScan 2011-2020) and publicly (Medicaid Analytic eXtract/Transformed Medicaid Statistical Information System Analytic Files 2011-2018) insured pregnancies ending in live birth from 2 health care utilization databases. Medication use was based on filled prescriptions between the date of last menstrual period through delivery, as well as the period before the last menstrual period and during specific trimesters. We also included a cross-sectional representative sample of pregnancies ascertained by the National Health and Nutrition Examination Survey (2011-2020), with information on prescription medication use during the preceding month obtained through maternal interviews. Teratogen Information System was used to classify the available evidence on teratogenic risk.

RESULTS

Among over 3 million pregnancies, the medications most commonly dispensed at any time during pregnancy were analgesics, antibiotics, and antiemetics. The top medications were ondansetron (16.8%), amoxicillin (13.5%), and azithromycin (12.4%) in MarketScan, nitrofurantoin (22.2%), acetaminophen (21.3%; mostly as part of acetaminophen-hydrocodone products), and ondansetron (19.5%) in Medicaid Analytic eXtract/Transformed Medicaid Statistical Information System Analytic Files, and levothyroxine (5.0%), sertraline (2.9%), and insulin (2.9%) in the National Health and Nutrition Examination Survey group. The most commonly dispensed suspected teratogens during the first trimester were antithyroid medications. The use of antidiabetic and psychotropic medications has continued to increase in the United States during the last decade, opioid dispensation has decreased by half, and antibiotics and antiemetics continue to be common. For one-quarter of medications, there is insufficient evidence available to characterize their safety profile in pregnancy.

CONCLUSION

There is a need for more drug research in pregnant patients. Future research should focus on anti-infectives with high utilization and limited level of evidence on safety for use during pregnancy. Although lack of evidence is not evidence of safety concerns, it does not indicate risk either. In many instances, the benefits outweigh the risks when these medications are used clinically, and some of the medications with no proven safety may be necessary to treat patients.

Levothyroxine Prescription Error: A Case Report

Levothyroxine (LT) is the synthetic form of thyroxine (T4), a thyroid hormone analog used to treat hypothyroidism. LT overdose rarely results in severely poor outcomes. General guidelines for treating exogenous thyrotoxicosis depend on the severity of symptoms. There is no standardized protocol; however, drug discontinuation, beta-blockers (specifically propranolol), and cholestyramine effectively manage overdose when needed, with most cases resolving independently without medical intervention.  Here, we present the case of a 26-year-old female with a history of supraventricular tachycardia, anxiety, depression, and Hashimoto thyroiditis who was accidentally overprescribed LT (300 mcg for one and a half months) that resulted in symptoms of lethargy, tremors, body temperature dysregulation, orthostatic hypotension, and diarrhea. This case, with limited evidence, suggests that excessive LT exacerbated the patient's underlying psychiatric symptoms, encouraging suicidal ideation.

Thermogenic T cells: a cell therapy for obesity?

Obesity is a widespread public health problem with profound medical consequences and its burden is increasing worldwide. Obesity causes significant morbidity and mortality and is associated with conditions including cardiovascular disease and diabetes mellitus. Conventional treatment options are insufficient, or in the case of bariatric surgery, quite invasive. The etiology of obesity is complex, but at its core is often a caloric imbalance with an inability to burn off enough calories to exceed caloric intake, resulting in storage. Interventions such as dieting often lead to decreased resting energy expenditure (REE), with a rebound in weight ("yo-yo effect" or weight cycling). Strategies that increase REE are attractive treatment options. Brown fat tissue engages in nonshivering thermogenesis whereby mitochondrial respiration is uncoupled from ATP production, increasing REE. Medications that replicate brown fat metabolism by mitochondrial uncoupling (e.g., 2,4-dinitrophenol) effectively promote weight loss but are limited by toxicity to a narrow therapeutic range. This review explores the possibility of a new therapeutic approach to engineer autologous T cells into acquiring a thermogenic phenotype like brown fat. Engineered autologous T cells have been used successfully for years in the treatment of cancers (chimeric antigen receptor T cells), and the principle of engineering T cells ex vivo and transferring them back to the patient is established. Engineering T cells to acquire a brown fat-like metabolism could increase REE without the risks of pharmacological mitochondrial uncoupling. These thermogenic T cells may increase basal metabolic rate and are therefore a potentially novel therapeutic strategy for obesity.

Relative Adrenocortical Insufficiency Following Radioactive Iodine Therapy for Graves' Disease: A Report of Two Cases

Introduction

In recent years, radioactive iodine (RAI) therapy has become a main choice for Graves' disease. The rapid release of thyroid hormones following RAI may on occasion trigger severe events, such as thyroid storm or heart block. This study presents two cases of possible acute adrenocortical insufficiency precipitated by radioiodine therapy.

Case Presentation

Two females aged 65 and 19 years with long-standing Graves' disease underwent radioiodine treatment at our clinical center. Both patients suffered nausea, fatigue, aggravated palpitation, and relative hypotension thereafter. Laboratory data showed severe thyrotoxicosis with free thyroxine higher than three times the upper limit, while basal serum cortisol (8 AM) was below the lower limit (5.08 μg/dL and 2.08 μg/dL respectively) under stress, indicating a potential relative adrenocortical insufficiency. There was then full recovery after adequate hydrocortisone therapy. As thyrotoxicosis resolved, the levels of basal cortisol were subsequently raised to normal.

Conclusion

Post-RAI adrenocortical insufficiency might occur in patients with severe Graves' disease. Basal serum cortisol might be a cost-effective parameter for the identification of potential patients.