Subclinical thyroid disease

Maternal subclinical hyperthyroidism and adverse pregnancy outcomes considering the iodine status: Tehran thyroid and pregnancy study

BACKGROUND

Unlike overt thyroid diseases, the impacts of subclinical thyroid dysfunction, especially subclinical hyperthyroidism (SH), on adverse pregnancy outcomes are inconclusive.

OBJECTIVE

We aimed to investigate the effect of maternal SH on adverse maternal and neonatal outcomes based on urinary iodine concentration (UIC).

METHODS

A secondary analysis was run on data collected in the Tehran Thyroid and Pregnancy study (TTPs). We used the data of 131 women with SH and 1650 cases of euthyroid. Serum levels of thyroid-stimulating hormone (TSH), thyroxine (T4), free thyroxine index (FT4I), and thyroid peroxidase antibody (TPOAb) were assessed at the first prenatal visit. A generalized linear regression model was applied to identify the effect of SH on the pregnancy outcomes based on UIC, and the effects were estimated with a 95% confidence interval.

RESULTS

Preterm delivery was observed in 12.3% of women with SH and 6.7% of those with euthyroid (P = 0.03). Women with TSH< 0.3 mIU/L had a higher odds of preterm delivery than those with TSH≥ 0.3 regardless of urine iodine cut-off [OR= 2.27; 95% CI: (1.15, 4.48), p = 0.02]. Among those with UIC levels≥ 150 μg/L, the odds ratio of preterm delivery was 4.61 folds higher in the SH group compared to those with euthyroid [95%CI: (1.36, 15.71), p = 0.01)]. No significant difference between these two study groups was found in Neonatal Intensive Care Unit admission. Moreover, the results revealed no statistically significant difference in the means of neonatal anthropometric parameters in the SH and euthyroid groups in none of the subgroups of UIC (<150 or ≥150 µg/l).

CONCLUSIONS

According to our results, maternal SH appears to be a risk factor for preterm delivery. This effect is more pronounced in women with higher UIC than those with lower UIC.

Genetic association and Mendelian randomization for hypothyroidism highlight immune molecular mechanisms

We carried out a genome-wide association analysis including 51,194 cases of hypothyroidism and 443,383 controls. In total, 139 risk loci were associated to hypothyroidism with genes involved in lymphocyte function. Candidate genes associated with hypothyroidism were identified by using molecular quantitative trait loci, colocalization, and enhancer-promoter chromatin looping. Mendelian randomization (MR) identified 42 blood expressed genes and circulating proteins as candidate causal molecules in hypothyroidism. Drug-gene interaction analysis provided evidence that immune checkpoint and tyrosine kinase inhibitors used in cancer therapy increase the risk of hypothyroidism. Hence, integrative mapping and MR support that expression of genes and proteins enriched in lymphocyte function are associated with the risk of hypothyroidism and provide genetic evidence for drug-induced hypothyroidism and identify actionable potential drug targets.

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GWAS for hypothyroidism identified 139 risk loci including 76 novel associations

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GWAS was enriched in pathways related to lymphocyte function

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In total, 28 potentially deleterious missense variants were identified

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Mendelian randomization and colocalization identified 61 blood causal candidate genes

Hyperthyroid cats and their kidneys: a literature review

Hyperthyroidism and chronic kidney disease (CKD) are common diseases of geriatric cats, and often occur concurrently. Thus, a thorough understanding of the influence of thyroid function on renal function is of significant value for all feline practitioners. Among other effects, hyperthyroidism causes protein catabolism and increases renal blood flow and glomerular filtration rate (GFR). These effects render traditional renal markers insensitive for the detection of CKD in cats with uncontrolled hyperthyroidism. Furthermore, the development of iatrogenic hypothyroidism with over treatment of hyperthyroidism can be detrimental to renal function and may negatively affect long-term survival. This review discusses important diagnostic considerations of feline hyperthyroidism, as well as key treatment modalities, with an emphasis on the use of radioiodine and the importance of post treatment monitoring of thyroid and renal parameters. In Australia, a common curative treatment for cats with benign hyperthyroidism (i.e. thyroid hyperplasia or adenoma) is a fixed dose of orally administered radioiodine, regardless of the serum total thyroxine concentration at the time of diagnosis. This review discusses the long term outcomes of this standard of care in comparison with current, relevant research literature from around the world. Finally, this review explores the use of symmetric dimethylarginine (SDMA) in assessing renal function before and after treatment in hyperthyroid cats. SDMA correlates well with GFR and creatinine in non-hyperthyroid cats, but our understanding of its performance in hyperthyroid cats remains in its infancy.

Maternal Subclinical Hyperthyroidism and Adverse Pregnancy Outcomes: A Systematic Review and Meta-analysis of Observational Studies

CONTEXT

Findings from studies evaluating adverse pregnancy outcomes in pregnant women with subclinical hyperthyroidism are conflicting and inconclusive.

OBJECTIVES

In this systematic review and meta-analysis, our aim was to evaluate the pooled odds ratio (OR) of adverse pregnancy outcomes in women with subclinical hyperthyroidism, compared to euthyroid women.

DATA SOURCES

Scopus, PubMed (including Medline), and Web of Science databases were systemically searched for regaining published studies to January 2022 examining adverse pregnancy outcomes in women with subclinical hyperthyroidism.

STUDY SELECTION

Outcomes of interest were classified into seven composite outcomes, including hypertensive disorders, preterm delivery, macrosomia/large for gestational age (LGA), pregnancy loss, adverse maternal outcomes, adverse neonatal outcomes, and adverse fetal outcomes.

DATA EXTRACTION

In this meta-analysis, both fixed and random effect models were used. Publication bias was also evaluated by Egger test and the funnel plot, and the trim and fill method was conducted in case of a significant result, to adjust the bias.

RESULTS

Of 202 records retrieved through searching databases, 11 studies were selected for the final analyses. There were no significant differences in pooled ORs of hypertensive disorders, preterm delivery, macrosomia/LGA, and pregnancy loss in pregnant women with subclinical hyperthyroidism, compared to the euthyroid controls. The pooled OR of adverse maternal, neonatal, and fetal outcomes in pregnant women with subclinical hyperthyroidism was not statistically significantly different from that of the euthyroid control group.

CONCLUSIONS

The current meta-analysis demonstrated that subclinical hyperthyroidism in pregnancy is not related with adverse maternal and fetal outcomes. Therefore, clinicians should be avoided unnecessary treatments for pregnant women with subclinical hyperthyroidism.

Biochemical pattern of thyroid function test and clinical impression of thyroid disorder in a rural tertiary health institution in Nigeria

Background

Thyroid disorders are one of the most common endocrine disorders seen globally. Diagnostic challenge may arise both clinically and biochemically because of the multiple function of thyroid hormones (THs). Request for thyroid function test (TFT s) may be based on clinical impression that may suggest thyroid dysfunction or obvious symptoms and signs that are diagnostic of hyperthyroidism or hypothyroidism.

Materials and Methods

This retrospective study looks at the biochemical patterns of TFTs and the clinical impression of thyroid disorders in a rural tertiary institution. Information extracted from the laboratory register includes indication for the test, the hospital number, the gender, the age, and the THs assayed. The corresponding biochemical pattern of the TFT result was established.

Results

A total of 297 requests were submitted for TH assay; 34 were excluded from the present study because there were no clinical information. There were 239 females and 24 males giving a female-to-male ratio of 9.9:1. Majority of the requests (36.5%) were for goiters, followed by gynecological disorders (20.9%) and clinical thyroid disorders (17.9%). About 46% (45.8%) of the goiter cases were biochemically euthyroid, whereas 13.5% were biochemically primary hyperthyroid. Among the 47 cases of thyroid disorders by the physician's clinical impression, 27.7% were euthyroid, 17% were biochemically hyperthyroid, and 10.6% were hypothyroid. Of the 55 gynecological disorders assessed, only 7.3% show biochemical evidence of TH alteration with 56.4% being euthyroid. About 47% (46.6%) of those that did routine medical examination had altered TH level that includes hyperthyroidism and hypothyroidism.

Conclusion

Goiter is the most prevalent thyroid disorder in this environment. Biochemical pattern of thyroid function test in our environment was mostly euthyroid despites clinical features suggestive of thyroid disorders.

Environmental exposure to pesticides and risk of thyroid diseases

Occupational and environmental exposure to pesticides has been associated with thyroid dysfunction, particularly changes in circulating thyroid hormone levels (T3, T4) and thyroid stimulating hormone (TSH). This study assessed the association between environmental exposure to pesticides and the risk of developing thyroid diseases. A population-based case-control study was carried out among Spanish populations living in areas categorized as of high or low pesticide use according to agronomic criteria, which were used as surrogates for environmental exposure to pesticides. The study population consisted of 79.431 individuals diagnosed with goiter, thyrotoxicosis, hypothyroidism, and thyroiditis (according to the International Classification of Diseases, Ninth Revision) and 1.484.257 controls matched for age, sex and area of residence. Data were collected from computerized hospital records for the period 1998 to 2015. Prevalence rates and risk of having thyroid diseases were significantly higher in areas with higher pesticide use, with a 49% greater risk for hypothyroidism, 45% for thyrotoxicosis, 20% for thyroiditis and 5% for goiter. Overall, this study indicates an association between increased environmental exposure to pesticides as a result of a greater agricultural use and diseases of the thyroid gland, thus supporting and extending previous evidence. This study also provides support to the methodology proposed for real-life risk simulation, thus contributing to a better understanding of the real life threat posed by exposure to multiple pesticides from different sources.

Prevalence of antithyroperoxidase antibodies in a multiethnic Brazilian population: The ELSA-Brasil Study

OBJECTIVE

In this study, we aimed to describe the prevalence and distribution of positive antithyroperoxidase antibodies (TPOAb) according to sex, age strata, and presence of thyroid dysfunction using baseline data from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

MATERIALS AND METHODS

Thyroid hormone tests were obtained from each study participant at baseline. Levels of thyroid-stimulating hormone (TSH) and free thyroxine (FT4) were measured using a third-generation immunoenzymatic assay. Antithyroperoxidase antibodies were measured by electrochemiluminescence and were considered to be positive when ≥ 34 IU/mL.

RESULTS

The prevalence of TPOAb among 13,503 study participants was 12%. Of participants with positive TPOAb, 69% were women. Almost 60% of the individuals with positive TPOAb were white. The presence of positive TPOAb was associated with the entire spectrum of thyroid diseases among women, but only with overt hyperthyroidism and overt hypothyroidism in men.

CONCLUSION

The distribution of positive TPOAb across sex, race, age, and thyroid function in the ELSA-Brasil study is aligned with the worldwide prevalence of positive TPOAb reported in iodine-sufficient areas. In women, the presence of TPOAb was related to the entire spectrum of thyroid dysfunction, while in men, it was only related to the occurrence of overt thyroid disease.

Hypertension in Thyroid Disorders

Arterial hypertension represents a major global health concern; more than one fourth of the population is affected by high blood pressure. Albeit the underlying cause of the disease remains unclear in the vast majority of the cases, ~10% are of secondary origin. Endocrine disorders are common illnesses and some of them may lead to elevated blood pressure, among which thyroid diseases are of high prevalence and often overlooked, especially in mild cases. Overt and subclinical hyper- and hypothyroidism can both lead to (mostly mild) hypertension; however, the underlying mechanisms are only partially understood. The results of clinical studies are often controversial. During the past decades, some genetic mutations in the hypothalamus-pituitary-thyroid axis with cardiovascular consequences were revealed. Atherosclerotic changes resulting from lipid abnormalities due to thyroid dysfunction also affect the vasculature and can cause elevated blood pressure. The review gives a synopsis of our knowledge how thyroid hormone metabolism and functional thyroid diseases affect the cardiovascular system, their negative impact and causative role in the development of hypertension.

The debate on treating subclinical hypothyroidism

Subclinical hypothyroidism (SCH) represents a mild or compensated form of primary hypothyroidism. The diagnosis of SCH is controversial, as its symptoms are non-specific and its biochemical diagnosis is arbitrary. The treatment of SCH was examined among non-pregnant adults, pregnant adults and children. In non-pregnant adults, treatment of SCH may prevent its progression to overt hypothyroidism, reduce the occurrence of coronary heart disease, and improve neuropsychiatric and musculoskeletal symptoms associated with hypothyroidism. These benefits are counteracted by cardiovascular, neuropsychiatric and musculoskeletal side effects. SCH is associated with adverse maternal and fetal outcomes that may improve with treatment. Treating SCH in children is safe and may improve growth. Importantly, the evidence in this field is largely from retrospective and prospective studies with design limitations, which precludes a conclusive recommendation for the treatment of SCH.

Subclinical hypothyroidism in paediatric population treated with levothyroxine: a real-world study on 2001-2014 Italian administrative data

OBJECTIVE

To estimate the prevalence of subclinical hypothyroidism (SH) among children, by using levothyroxine low dosage as disease proxy, and to describe prescription pattern.

DESIGN

An historical cohort study was performed through administrative databases of 12 Italian Local Health Units covering 3,079,141 inhabitants. A cohort of children (aged 0-13 years) was selected in the period 2001-2014. A subgroup of new users (aged 0-9 years) was identified and followed up for 5 years.

METHODS

The prevalence was provided as mean value of the whole period, as annual trend, by patient gender and age. Demographic details, information on levothyroxine dosage, comorbidities and co-medications were provided. Therapy duration and medication persistence were evaluated among new users.

RESULTS

644 children treated with levothyroxine low dosage was selected, with a mean annual prevalence of 0.20 per 1000 children. The temporal trend of prevalence was stable, with a slight reduction in the 2005-2008. Prevalence by age showed an increase after 10 years. Patients were treated with an average annual dose of 4290 µg/year and 66.9% of children were affected by comorbidities. Among 197 new users, 62.9% received therapy only for one year, whereas out of those treated two or more years, 89.0% resulted persistent to the therapy.

CONCLUSIONS

This study provides real-world epidemiology of SH among children, and it depicts the clinical and therapeutic characteristics of these subjects. Its findings showed that the SH treatment of this disorder was widely variable, also due to lack of evidence concerning paediatric population.

Evaluation of the Female Patients with Subclinical Hypothyroidism by Brainstem Auditory Evoked Potentials: Case-Control Study

INTRODUCTION

Hypothyroidism, a common endocrinological disorder is quite prevalent in its subclinical state in the adult population. Nervous system involvement is frequent in hypothyroidism with documentation of peripheral and central conduction delays as abnormal latency prolongations in Brainstem Auditory Evoked Potential (BAEP) records. Subclinical hypothyroidism however, has been less extensively studied for investigating the involvement of the auditory functions.

AIM

To assess the auditory functions and Central Nervous System (CNS) involvement in the patients with subclinical hypothyroidism by recording BAEP.

MATERIALS AND METHODS

The study comprised of 50 females (25 females with subclinical hypothyroidism and 25 age-matched healthy females) in the age-group of 30-50 years. BAEP absolute and Interpeak Latencies (IPLs) (I, III and V, I-III, III-V and I-V) were compared between the two groups by unpaired t-test. The p<0.05 was considered as statistically significant.

RESULTS

Mean BAEP absolute latencies (III and V) increased in the subjects with subclinical hypothyroidism as compared to controls (p<0.001) (both the ears) and wave I absolute latency also increased with p<0.001 (both the ears) by unpaired t-test. Among IPLs (interpeak latencies), III-V and I-V IPLs exhibited increase (p<0.01), while I-III IPL did not vary with statistical significance (both the ears) in the two groups.

CONCLUSION

Patients with subclinical hypothyroidism were found to demonstrate central as well as peripheral auditory pathway affections. BAEPs can prove valuable and sensitive tests to detect involvement of the CNS and auditory dysfunctions earlier in hypothyroidism.

Efficacy of Low-dose (2 millicurie) versus Standard-dose (4 millicurie) Radioiodine Treatment for Cats with Mild-to-Moderate Hyperthyroidism

Background

Radioiodine (¹³¹I) is effective treatment for hyperthyroidism in cats, but optimal dose to restore euthyroidism without inducing hypothyroidism is unclear. Treatment‐induced hypothyroidism can lead to azotemia and reduced duration of survival.

Objective

To compare efficacy and short‐term outcomes of low‐dose ¹³¹I versus higher, standard‐dose ¹³¹I as treatment for hyperthyroidism.

Animals

A total of 189 client‐owned cats undergoing ¹³¹I treatment for mild‐to‐moderate hyperthyroidism (serum T₄ ≥ 4.0 μg/dL and <13.0 μg/dL).

Methods

Prospective, nonrandomized, cohort study comparing treatment with either low‐dose (2 mCi, n = 150) or standard‐dose (4 mCi, n = 39) ¹³¹I. Serum T₄, thyroid‐stimulating hormone (TSH), and creatinine concentrations were measured after 1, 3, and 6 months to determine persistent hyperthyroidism, overt hypothyroidism (low T₄, high TSH), subclinical hypothyroidism (normal T₄, high TSH), and azotemia.

Results

There was no significant difference in prevalence of cats with persistent hyperthyroidism between standard‐ and low‐dose treatment groups at 3 (0% versus 5.3%; P = .34) and 6 (0% versus 3.3%; P = .51) months. Overt (18% versus 1%; P = .0005) or subclinical (46% versus 21%; P = .004) hypothyroidism was more common in cats at 6 months after standard‐dose ¹³¹I. No difference in incidence of azotemia existed between groups, but cats treated with standard‐dose ¹³¹I had higher creatinine concentrations (P < .05) and higher percent rises in creatinine (P < .0001).

Conclusions and Clinical Importance

Low‐dose ¹³¹I is safe and effective for cats with mild‐to‐moderate hyperthyroidism, as evidenced by a cure rate of >95% with reduced frequency of iatrogenic hypothyroidism and azotemia.

Symptoms of thyrotoxicosis, bone metabolism and occult atrial fibrillation in older women with mild endogenous subclinical hyperthyroidism

OBJECTIVE

The objective of this study was to evaluate symptoms of thyrotoxicosis, bone turnover, bone mineral density (BMD) and occult atrial fibrillation (AF) in women ≥65 years with mild endogenous subclinical hyperthyroidism (SCH).

DESIGN

Cross-sectional and case-control study.

PATIENTS

Signs and symptoms of thyrotoxicosis, serum carboxyterminal telopeptide (CTx) and procollagen type I N-terminal propeptide (PINP), BMD, resting electrocardiogram (ECG) and 72-h ECG monitoring were evaluated in 180 women ≥65 years, including 90 with mild SCH (TSH between 0·1 and 0·4 mIU/l) and 90 euthyroid controls matched for age and body mass index.

RESULTS

Symptom Rating Scale scores did not differ between patients and controls. None of the patients with SCH scored 20 points, a score compatible with clinical thyrotoxicosis. Eighty patients with SCH (89%) obtained seven or fewer points, a score compatible with euthyroidism. No difference in serum CTx or PINP concentrations was observed between patients and controls. There was also no correlation between these markers and TSH, free T4 or total T3 levels. Finally, no difference in femoral neck or lumbar spine BMD was observed between patients with SCH and controls. Three patients with SCH (3·3%) and two euthyroid women (2·2%) had known AF or AF in the resting ECG. ECG monitoring for 72 h revealed episodes of occult AF in 1/87 patients with SCH and in 1/88 euthyroid women (1·1%).

CONCLUSIONS

Mild endogenous SCH (TSH between 0·1 and 0·4 mIU/l) was not associated with symptoms of thyrotoxicosis, altered bone metabolism or a higher prevalence of occult AF in women ≥65 years.

Subclinical hypothyroidism might worsen the effects of aging on serum lipid profiles: a population-based case-control study

BACKGROUND

Dyslipidemia is an important global health problem, particularly in the elderly population. Traditionally, the high prevalence of dyslipidemia in elderly people is considered a "natural condition." Notably, subclinical hypothyroidism (SCH) is one of the most important risk factors for dyslipidemia. Few studies have assessed whether SCH plays a role in the increase in age-related dyslipidemia. This study aimed to explore the association between SCH and lipid profiles in different age groups.

METHODS

This was a large-scale, population-based, case-control study. The population was derived from the REACTION study conducted across China. A total of 17,046 individuals (8827 cases and 8219 controls) aged 40 years or older were enrolled in the final analyses. The relationships between SCH and serum lipid parameters in each age group were evaluated after adjustment for thyroid hormones and common confounding factors.

RESULTS

In the entire population, thyrotropin (TSH), the key indicator of SCH, was positively associated with cholesterol parameters (total cholesterol [TC] and low-density lipoprotein cholesterol [LDL-C]) through the sixth decade of life. After adjusting for common confounding factors and thyroid hormones, each 1 mIU/L increase in TSH was estimated to elevate the TC level by 0.0147 mmol/L and 0.0551 mmol/L, respectively, in individuals aged 40-49 years and 60-69 years. Similarly, with each 1 mIU/L increase in TSH, the LDL-C level tended to show gradually greater increases as age increased. In moderately old subjects (60-69 years), mild (TSH≤10 mIU/L) and significant (TSH>10 mIU/L) SCH increased the concentration of TC approximately 1.03- and 1.36-fold, and the concentration of LDL-C approximately 1.19- and 1.65-fold, respectively, when compared with younger subjects.

CONCLUSIONS

TSH exhibited a stronger effect on the TC and LDL-C level in moderately old subjects than in younger subjects. SCH might augment and worsen the effects of aging on serum lipid profiles.

Thyroid-stimulating hormone inhibits adipose triglyceride lipase in 3T3-L1 adipocytes through the PKA pathway

Thyroid-stimulating hormone (TSH) has been shown to play an important role in the regulation of triglyceride (TG) metabolism in adipose tissue. Adipose triglyceride lipase (ATGL) is a rate-limiting enzyme controlling the hydrolysis of TG. Thus far, it is unclear whether TSH has a direct effect on the expression of ATGL. Because TSH function is mediated through the TSH receptor (TSHR), TSHR knockout mice (Tshr-/- mice) (supplemented with thyroxine) were used in this study to determine the effects of TSHR deletion on ATGL expression. These effects were verified in 3T3-L1 adipocytes and potential underlying mechanisms were explored. In the Tshr-/- mice, ATGL expression in epididymal adipose tissue was significantly increased compared with that in Tshr+/+ mice. ATGL expression was observed to increase with the differentiation process of 3T3-L1 preadipocytes. In mature 3T3-L1 adipocytes, TSH significantly suppressed ATGL expression at both the protein and mRNA levels in a dose-dependent manner. Forskolin, which is an activator of adenylate cyclase, suppressed the expression of ATGL in 3T3-L1 adipocytes. The inhibitory effects of TSH on ATGL expression were abolished by H89, which is a protein kinase A (PKA) inhibitor. These results indicate that TSH has an inhibitory effect on ATGL expression in mature adipocytes. The associated mechanism is related to PKA activation.

Thyrotropin increases hepatic triglyceride content through upregulation of SREBP-1c activity

BACKGROUND & AIMS

Hallmarks of non-alcoholic fatty liver disease (NAFLD) are increased triglyceride accumulation within hepatocytes. The prevalence of NAFLD increases steadily with increasing thyrotropin (TSH) levels. However, the underlying mechanisms are largely unknown. Here, we focused on exploring the effect and mechanism of TSH on the hepatic triglyceride content.

METHODS

As the function of TSH is mediated through the TSH receptor (TSHR), Tshr(-/-) mice (supplemented with thyroxine) were used. Liver steatosis and triglyceride content were analysed in Tshr(-/-) and Tshr(+/+) mice fed a high-fat or normal chow diet, as well as in Srebp-1c(-/-) and Tshr(-/-)Srebp-1c(-/-) mice. The expression levels of proteins and genes involved in liver triglyceride metabolism was measured.

RESULTS

Compared with control littermates, the high-fat diet induced a relatively low degree of liver steatosis in Tshr(-/-) mice. Even under chow diet, hepatic triglyceride content was decreased in Tshr(-/-) mice. TSH caused concentration- and time-dependent effects on intracellular triglyceride contents in hepatocytes in vitro. The activity of SREBP-1c, a key regulator involved in triglyceride metabolism and in the pathogenesis of NAFLD, was significantly lower in Tshr(-/-) mice. In Tshr(-/-)Srebp-1c(-/-) mice, the liver triglyceride content showed no significant difference compared with Tshr(+/+)Srebp-1c(-/-) mice. When mice were injected with forskolin (cAMP activator), H89 (inhibitor of PKA) or AICAR (AMPK activator), or HeG2 cells received MK886 (PPARα inhibitor), triglyceride contents presented in a manner dependent on SREBP-1c activity. The mechanism, underlying TSH-induced liver triglyceride accumulation, involved that TSH, through its receptor TSHR, triggered hepatic SREBP-1c activity via the cAMP/PKA/PPARα pathway associated with decreased AMPK, which further increased the expression of genes associated with lipogenesis.

CONCLUSIONS

TSH increased the hepatic triglyceride content, indicating an essential role for TSH in the pathogenesis of NAFLD.