Treatment Of Subclinical Hypothyroidism Research Articles

Hypothyroidism and metabolic cardiovascular disease.

Cardiovascular disease (CVD) remains the leading cause of death worldwide, representing a major health issue of social and economic relevance. Both hyperthyroidism and hypothyroidism are very common in the adult population, and both disorders may contribute to the onset and progression of CVD. After a brief description of the role of thyroid hormones (THs) on the physiology of the cardiovascular system and the potential mechanism that links THs alterations with changes in cardiac function, blood pressure, endothelial function, and lipid levels, we review updated data about the clinical impact of overt hypothyroidism (OH) and subclinical hypothyroidism (SCH) on CV risk, CVD, and mortality. Furthermore, we summarize the current evidence for treating SCH with levothyroxine (L-T4). Several guidelines of distinguished endocrine societies recommend treatment for SCH with TSH higher than 10 mIU/L, where the benefit of L-T4 therapy is more evident for younger people, but still controversial in those aged over 65 years. Based on current knowledge, more research efforts are needed to better address the clinical management of CV risk and CVD in the elderly affected by SCH.

Patient-Reported Satisfaction with Thyroid Hormone Replacement Therapy for Subclinical Hypothyroidism in Older Adults: A Pooled Analysis of Individual Participant Data from Two Randomized Controlled Trials.

Background: The benefit of levothyroxine treatment of subclinical hypothyroidism (SCH) is subject to debate. This study compared treatment satisfaction between older adults with SCH using levothyroxine or placebo. Methods: We analyzed pooled individual participant data from two randomized, double-blind, placebo-controlled trials investigating the effects of levothyroxine treatment in older adults with SCH. Community-dwelling participants aged ≥65 years, with SCH (persistent thyrotropin levels 4.60-19.99 mIU/L for >3 months and normal free T4 level), were included. Intervention dose titration until thyrotropin levels normalized, with a mock dose adjustment of placebo. Treatment satisfaction was determined during the final study visit using the Treatment Satisfaction Questionnaire for Medication (TSQM), encompassing perceived effectiveness, side effects, convenience, and global satisfaction, along with the participants' desire to continue study medication after the trial. Results: We included 536 participants. At baseline, the median (interquartile range [IQR]) age was 74.9 (69.7-81.4) years, and 292 (55%) were women. The median (IQR) thyrotropin levels were 5.80 (5.10-7.00) mIU/L at baseline in both groups; at final visit, 4.97 (3.90-6.35) mIU/L in the placebo and 3.24 (2.49-4.41) mIU/L in the levothyroxine group. After treatment, the groups did not differ significantly in global satisfaction (mean difference [CI] -1.1 [-4.5 to 2.1], p = 0.48), nor in any other domain of treatment satisfaction. These results held true regardless of baseline thyrotropin levels or symptom burden. No major differences were found in the numbers of participants who wished to continue medication after the trial (levothyroxine 35% vs. placebo 27%), did not wish to continue (levothyroxine 27% vs. placebo 30%), or did not know (levothyroxine 37% vs. placebo 42%) (p = 0.14). In a subpopulation with high symptom burden from hypothyroid symptoms at baseline, those using levothyroxine more often desired to continue the medication after the trial than those using placebo (mean difference [CI]: -21.1% [-35.6% to -6.5%]). Conclusion: These pooled data from two RCTs showed no major differences in treatment satisfaction between older adults receiving levothyroxine or placebo. This finding has important implications for decision-making regarding initiating levothyroxine treatment for SCH. Our findings generally support refraining from routinely prescribing levothyroxine in older adults with SCH.

Effects of Levothyroxine Treatment on Fertility and Pregnancy Outcomes in Subclinical Hypothyroidism: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Background: Subclinical hypothyroidism, defined by elevated thyrotropin (TSH) and normal free thyroxine levels, is associated with adverse pregnancy outcomes, including preterm birth, pre-eclampsia, and small for gestational age. Despite the uncertainty regarding the effectiveness of levothyroxine (LT4) treatment on pregnancy outcomes in subclinical hypothyroidism, LT4 is widely administered with a pre-treatment threshold TSH level of 2.5 mU/L. The aim of this study is to investigate the efficacy of periconceptional LT4 treatment for subclinical hypothyroidism, including TSH levels >2.5 mU/L, and identify the characteristics of subclinical hypothyroidism that can benefit from LT4 treatment. Methods: We conducted a systematic review and meta-analysis of randomized controlled trials from inception to February 2023. We analyzed the pooled effects of LT4 on subclinical hypothyroidism before and during pregnancy. The main outcomes before pregnancy were live birth, pregnancy, and miscarriage. The main outcomes during pregnancy were live birth, miscarriage, and preterm birth. We conducted subgroup analyses to compare the effects of LT4 on subclinical hypothyroidism with TSH levels of 2.5-4.0 and >4.0 mU/L. Results: Of the 888 studies identified, 27 full-text articles were screened for eligibility. Five studies on pre-conception treatment with 768 participants and eight studies on treatment during early pregnancy with 2622 participants were analyzed. One of the two studies on pre-conception treatment in subclinical hypothyroidism with TSH >4.0 mU/L had high risk of bias and the other was composed of 64 participants. Pre-conception LT4 treatment had no significant effect in improving rates of live births and pregnancies, or reducing miscarriages (risk ratio [RR], 95% confidence interval): 1.41 (0.84-2.36), 1.73 (0.88-3.39), and 0.46 (0.11-2.00), respectively. LT4 treatment during pregnancy was not significantly associated with higher rates of live births (RR 1.03, 0.98-1.09) nor decreased miscarriage rates (RR 1.01, 0.66-1.53). The effect of LT4 treatment on preterm birth during pregnancy was significantly different depending on the TSH values (p = 0.04); a positive effect was shown in the subclinical hypothyroidism subgroup with TSH >4.0 mU/L (RR 0.47, 0.20-1.10), while no significant effect was observed in the subgroup with TSH 2.5-4.0 mU/L (RR 1.35, 0.79-2.31). Conclusions: Pre-conceptional LT4 treatment for subclinical hypothyroidism does not improve fertility or decrease the incidence of miscarriages. However, further well-designed studies are needed for pre-conceptional treatment, especially in TSH >4.0 mU/L. LT4 treatment during pregnancy had a positive effect on preterm birth; nevertheless, this was only applicable to subclinical hypothyroidism with TSH >4.0 mU/L.

Subclinical Hypothyroidism in Patients with Obesity and Metabolic Syndrome: A Narrative Review.

The literature on the connection between obesity, metabolic syndrome, and subclinical hypothyroidism is critically analyzed in this narrative review. These conditions are frequently observed among adult populations and various studies and meta-analyses have assessed their association. The prevalence of subclinical hypothyroidism in obese individuals is higher than in non-obese subjects and this trend is more pronounced in unhealthy obesity phenotypes. However, the diagnosis and treatment of subclinical hypothyroidism can be difficult in obese patients. Exaggerated body fat is linked to thyroid hypoechogenicity as evident through ultrasonography and euthyroid obese people have greater TSH, FT3, and FT3/FT4 ratios than non-obese individuals in a euthyroid condition. Moreover, a reduced expression of the TSH receptor and altered function of deiodinases has been found in the adipose tissue of obese patients. Current data do not support the necessity of a pharmacological correction of the isolated hyperthyrotropinemia in euthyroid obese patients because treatment with thyroid hormone does not significantly improve weight loss and the increase in serum TSH can be reversible after hypocaloric diet or bariatric surgery. On the other hand, obesity is linked to elevated leptin levels. Inflammation can raise the risk of Hashimoto thyroiditis, which increases the likelihood that obese patients will experience overt or subclinical hypothyroidism. Both metabolic syndrome and subclinical hypothyroidism are associated with atherosclerosis, liver and kidney disease. Hence, the association of these two illnesses may potentiate the adverse effects noted in each of them. Subclinical hypothyroidism should be identified in patients with obesity and treated with appropriate doses of L-thyroxine according to the lean body mass and body weight. Randomized controlled trials are necessary to verify whether treatment of thyroid deficiency could counteract the expected risks.

Levothyroxine initiation and the risk of pregnancy loss among pregnant women with subclinical hypothyroidism: An observational study emulating a target trial.

While the benefits of levothyroxine are well-established for overt hypothyroidism, they are unclear for subclinical hypothyroidism (SCH) among pregnant women. To estimate the effect of initiation of levothyroxine on pregnancy loss among women with SCH with an emulated target trial using observational data. We emulated a target trial using the United Kingdom's Clinical Practice Research Datalink to account for the staggered timing of diagnosis and treatment of SCH and the time of entry of women into prenatal care. We emulated multiple nested trials (at each gestational week) and used an intention-to-treat approach to define levothyroxine use (≥1 prescription in the 7 days prior to trial entry), with eligible users matched to non-users (1:4) on time of diagnosis, gestational week of the first eligible trial and high-dimensional propensity score. Pregnancy losses included spontaneous abortion and stillbirth. A pooled logistic regression model with bootstrap resampling was used to estimate the hazard ratios (HR) and 95% confidence intervals (CI). Based on 159,177 eligible person-trials (5781 women), the matched cohort included 181 initiators and 640 non-initiators of levothyroxine, with 57 pregnancy losses occurring during follow-up. Overall, the mean age of women was 32.2 years (SD 5.4), 25% were obese, 8% had type 2 diabetes and about 50% were nulliparous. After matching, women who initiated levothyroxine versus not had higher thyroid-stimulating levels during pregnancy and were more likely to have a history of hypothyroidism. The cumulative incidence of pregnancy loss was lower in initiators versus non-initiators of levothyroxine. The adjusted HR for pregnancy loss was 0.87 (95% CI 0.22, 1.56). Although our assessment of the effect of initiation of levothyroxine for SCH in pregnancy precludes any definitive conclusions due to wide confidence intervals, this study illustrates the feasibility of using the target trial emulation framework to examine the effectiveness of medication use in pregnancy.

Effects of treating subclinical hypothyroidism in pregnancy in India: Are we treating too many for little gain? A retrospective cohort study.

To assess the impact of treatment of subclinical hypothyroidism (SCH) on short-term pregnancy outcomes. Data from 4526 consecutive women with singleton pregnancies who delivered between January 2015 and December 2017 were analyzed. SCH was defined as a thyroid-stimulating hormone (TSH) level between 2.5 and 10 mU/mL with normal free thyroxine. Of those with SCH, some were treated but others were not. These two groups were compared using χ2 and Student t tests for categorical and continuous variables, respectively. Multiple logistic regression models, adjusted for maternal age, body mass index, parity, gestation at TSH measurement, and gestational diabetes mellitus status, were used to investigate the effect of treatment on pregnancy and neonatal outcomes. In all, 1227 (27.1%) of 4526 women had SCH, of whom 393 (32.0%) were treated. The mean age and body mass index were similar in both groups. The mean gestation at measuring of TSH was 11.7 ± 6.5 weeks. There was no significant difference in pregnancy or neonatal outcomes between the two groups. A sub-group analysis when SCH was defined as TSH 4.0 mU/mL or greater showed a higher rate of large for gestational age and lower rates of low birth weight and small for gestational age in the treated group. The prevalence of SCH based on the international guidelines threshold is high in India. Treatment of SCH did not show any difference in pregnancy and neonatal outcomes in this study.

Effect of levothyroxine treatment on fetal growth among women with mild subclinical hypothyroidism and thyroid peroxidase antibody negative: a cohort study

BackgroundSome clinicians used levothyroxine (LT4) treatment for mild subclinical hypothyroidism (SCH) pregnant women (2.5 < thyroid-stimulating hormone (TSH) ≤ the pregnancy-specific reference range with normal free thyroxine (FT4) level) with thyroid peroxidase antibody negative (TPOAb−), although the recent clinical guideline did not recommend it. It is unknown whether LT4 treatment for pregnant women with mild SCH and TPOAb− have impact on fetal growth. Therefore, the aim of the study was to investigate the effect of LT4 treatment on fetal growth and birth weight among mild SCH pregnant women with TPOAb−.MethodsThis was a birth cohort study including 14,609 pregnant women between 2016 and 2019 in Tongzhou Maternal and Child Health Hospital of Beijing, China. Pregnant women were divided into 3 groups as follows: Euthyroid (n = 14,285, 0.03 ≤ TSH ≤ 2.5mIU/L, normal FT4), TPOAb−; Untreated mild SCH with TPOAb− (n = 248, 2.5 < TSH ≤ 2.9mIU/L, normal FT4, without LT4 treatment); Treated mild SCH with TPOAb− (n = 76, 2.5 < TSH ≤ 2.9mIU/L, normal FT4, with LT4 treatment). The main outcome measures were Z-scores of fetal growth indicators (abdominal circumference (AC), biparietal diameter (BPD), femur length (FL), head circumference (HC), estimated fetal weight (EFW)), fetal growth restriction (FGR) and birth weight.ResultsThere was no difference in fetal growth indicators and birth weight between the untreated mild SCH women with TPOAb− and the euthyroid pregnant women. But the HC Z-score was lower in the LT4 treated mild SCH women with TPOAb−, compared with the euthyroid pregnant women (β = -0.223, 95%CI: -0.422, -0.023). The LT4 treated mild SCH women with TPOAb− had lower fetal HC Z-score (β = -0.236, 95%CI: -0.457, -0.015), compared with the untreated mild SCH women with TPOAb−.ConclusionsWe observed that LT4 treatment for mild SCH with TPOAb− was associated with decreased fetal HC, which was not observed for untreated mild SCH women with TPOAb−. The adverse effect of LT4 treatment for mild SCH with TPOAb− provided new evidence for the recent clinical guideline.

THE EFFECT OF LEVOTHYROXINE TREATMENT ON MATERNAL AND PERINATAL OUTCOMES IN PREGNANT WOMEN WITH SUBCLINICAL HYPOTHYROIDISM: A 5-YEAR RETROSPECTIVE STUDY AT A TERTIARY CARE HOSPITAL IN TURKEY

Subclinical hypothyroidism is characterized by elevated thyroid stimulating hormone (TSH) levels with normal free thyroxine (fT4) levels. The aim of this study was to compare obstetric and neonatal outcomes in pregnant women with and without treatment for subclinical hypothyroidism. In this study, maternal and perinatal outcomes were evaluated in a total of 270 pregnant women who were diagnosed with subclinical hypothyroidism as a result of screening performed in three trimesters of pregnancy between 2015 and 2020 and followed up in our clinic, 149 of whom received levothyroxine treatment and 121 of whom did not receive treatment. Further, different cutoff values for TSH were compared. The rates of neonatal intensive care unit (NICU) requirement were not different according to the levothyroxine use status of the patients (p=0.73, p&amp;gt;0.05). Miscarriage rates did not differ according to levothyroxine use (p=0,87, p&amp;gt;0,05). TSH, T4 and antithyroid peroxidase levels did not differ according to the maternal use of levothyroxine (p&amp;gt;0,05). Birth weight, gestational week at birth, 1- and 5-minute APGAR scores, neonatal TSH and T4 levels did not differ according to the maternal use of levothyroxine (p&amp;gt;0,05). Among the adverse maternal and perinatal outcomes, the need for NICU admission and the rates of placental abruption, fetal distress, preterm premature rupture of membranes, preeclampsia, preterm labor, and small for gestational age were not significantly different among the TSH cutoff groups (p&amp;gt;0,05). The rate of premature rupture of membranes was higher in the group with TSH levels ≥2.5 mIU/L (p=0.04). Choosing 2.5 mIU/L as the cutoff value for TSH levels allows early diagnosis of subclinical hypothyroidism with a higher rate in pregnant Turkish women and proactive therapeutic management. Our study provides limited evidence for the success of levothyroxine therapy for adverse obstetric and neonatal outcomes.

Treatment of Subclinical Hypothyroidism; A Review of Literature

Background: Subclinical hypothyroidism (SCH) is a disorder without any symptoms related with an elevated thyroid stimulating hormone (TSH) concentration &gt; 4 mIU/l and normal T4 and T3 concentrations. It is communal in the elderly and particularly in females, with prevalence of about 11%. Some studies show no effect of the treatment, while others have found it to be beneficial, since normal TSH levels can be above 7.5 mIU/L in the elderly. As a result of these findings, the best treatment for SCH, especially in elderly patients, has been criticized. Aim: The aim of this study was to evaluate the latest literature on the subject in order to assess the available evidence regarding this controversy in order to determine whether and under what conditions treatment of SCH is essential and how it can be prevented. Methods: To better understand the ongoing debate regarding the treatment of SCH, a Medline search of the English-language literature was held between 2015 and 2022 using the terms subclinical hypothyroidism, hypothyroidism, treatment and prevention, cardiovascular disease, dyslipidemia and cardiac failure. From this search, 38 articles with relevant material were selected. Results: When the data from these studies were combined, it was found that normal TSH levels increased with age, from 4 to 7.5 mIU/L in subjects under 75 years of age. Levothyroxine supplementation has also shown marked effects on the metabolic and clinical features of SCH, including decline in cardiovascular disease, heart failure, and mortality, although many of the peer-reviewed articles exhibited no treatment benefit. The drug works best in younger people who also experience fewer side effects. Conclusions: Younger patients with TSH &gt; 4.0 mIU/l should be treated for SCH based on available data. Treatment must be modified according to the TSH levels and existence of symptoms, and should be started with a TSH level of 10 mIU/L with moderate doses to minimize adversative cardiovascular complications in elderly patients. Keywords: subclinical, discussion, thyroxine, treatment, hypothyroidism, hypertension, thyrotropin, dyslipidemia, heart failure, cardiovascular diseases, prevention.

“Study of association of serum lipid profile, IL-6, &amp; ADMA levels with subclinical hypothyroidism”

Background &amp; Objectives: Subclinical hypothyroidism (SCH) represents the mildest form of thyroid hormone deficiency and may be associated with adverse consequences. SCH is defined as an elevated serum thyrotropin (often referred to as thyroid-stimulating hormone, or TSH) level with normal levels of free thyroxine (FT4) that affects up to 10% of the adult population. The identification of patients with subclinical hypothyroidism having an increased cardiovascular risk is of great importance in the present era. The aim of the study was to evaluate cardiovascular risk factors in patients with subclinical hypothyroidism.&#x0D; Methods: 120 patients with subclinical hypothyroidism and 120 age and gender matched healthy euthyroid controls in the age group of 18-70 years were included in the study. Body mass index (BMI), lipid profile, and levels of serum biomarkers were estimated in both the groups and further compared using student t-test. Lipid profile was also correlated with the serum ADMA &amp; IL-6 and the results were analyzed using Pearson’s correlation coefficient.&#x0D; Results: Patients with subclinical hypothyroidism had significantly higher levels of serum TSH, IL-6 and ADMA. Similarly, serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) were significantly increased and HDL-C was significantly decreased in SCH patients when compared to the same parameters of controls (p&lt;0.001). Significant positive correlations were found among lipid profile and serum IL-6 &amp; ADMA.&#x0D; Conclusions: The present study concluded that the SCH patients presented increased concentrations of cardiovascular disease (CVD) risk factors viz. IL-6, ADMA &amp; lipid profile. The potential benefits of diagnosis and treatment of subclinical hypothyroidism may have possible advantages firstly by preventing the progression to overt hypothyroidism and secondly decrease the risk of death from cardiovascular disease by starting appropriate therapy to improve lipid parameters.&#x0D;

The problems and prospects of diagnosis and treatment of hypothyroidism in special populations

The prevalence of thyroid diseases in China continues to increase, especially for hypothyroidism. This article focuses on the existing problems in the diagnosis and treatment of hypothyroidism in special groups, including obese patients, the elderly, children and pregnant women. The pathogenesis and intervention measures of obesity-induced hypothyroidism have been the hot research frontiers. The prevalence of subclinical hypothyroidism in the elderly is the highest, while its diagnostic criteria and treatment strategies are still controversial. The hazard and treatment of subclinical hypothyroidism and hypothyroxinemia during pregnancy have now become an international concern. And there also exist some problems in the screening, diagnosis and treatment of congenital hypothyroidism in children. So it is urgent to carry out high-quality clinical research to provide theoretical basis for clinical diagnosis and treatment, and carry out in-depth research on related mechanisms to establish a foundation for the construction of a scientific prevention and treatment system for hypothyroidism.

“Study of association of serum lipid profile, IL-6, &amp; ADMA levels with subclinical hypothyroidism”

Background &amp; Objectives: Subclinical hypothyroidism (SCH) represents the mildest form of thyroid hormone deficiency and may be associated with adverse consequences. SCH is defined as an elevated serum thyrotropin (often referred to as thyroid-stimulating hormone, or TSH) level with normal levels of free thyroxine (FT4) that affects up to 10% of the adult population. The identification of patients with subclinical hypothyroidism having an increased cardiovascular risk is of great importance in the present era. The aim of the study was to evaluate cardiovascular risk factors in patients with subclinical hypothyroidism. Methods: 120 patients with subclinical hypothyroidism and 120 age and gender matched healthy euthyroid controls in the age group of 18-70 years were included in the study. Body mass index (BMI), lipid profile, and levels of serum biomarkers were estimated in both the groups and further compared using student t-test. Lipid profile was also correlated with the serum ADMA &amp; IL-6 and the results were analyzed using Pearson’s correlation coefficient. Results: Patients with subclinical hypothyroidism had significantly higher levels of serum TSH, IL-6 and ADMA. Similarly, serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) were significantly increased and HDL-C was significantly decreased in SCH patients when compared to the same parameters of controls (p&lt;0.001). Significant positive correlations were found among lipid profile and serum IL-6 &amp; ADMA. Conclusions: The present study concluded that the SCH patients presented increased concentrations of cardiovascular disease (CVD) risk factors viz. IL-6, ADMA &amp; lipid profile. The potential benefits of diagnosis and treatment of subclinical hypothyroidism may have possible advantages firstly by preventing the progression to overt hypothyroidism and secondly decrease the risk of death from cardiovascular disease by starting appropriate therapy to improve lipid parameters.

Analysis of the relationship between subclinical hypothyroidism and anxiety and depression based on the theory of "Yi(liver) and Gui(kidney) from same source"

For a long time, the influence of subclinical thyroid dysfunction on anxiety and depression has been ignored, and the focus of research is on the influence of obvious thyroid dysfunction on mood. In recent years, the research on the effect of subclinical hypothyroidism on anxiety and depression has gradually increased, and the effect of subclinical hypothyroidism on mood has been re-emphasized. At present, the main measures for clinical diagnosis and treatment of subclinical hypothyroidism in China are clinical observation rather than drug intervention. In fact, patients do have negative emotional changes, which seriously affect people's sleep, study and work. Therefore, in this context, the advantages of traditional Chinese medicine are highlighted again. This paper aims to explore the essence of the relationship between subclinical hypothyroidism (SCH) and anxiety and depression based on the theory of "Yigui homology", so as to provide clinical diagnosis and treatment ideas.

Effect of Bushen Antai recipe on pyroptosis mechanism of subclinical hypothyroidism decidual cells in early pregnancy.

Subclinical hypothyroidism (SH) is common during pregnancy. It is not clear whether decidual cells in SH undergo pyroptosis during pregnancy. This study aimed to investigate the possible mechanism of Bushen Antai recipe (BAR) in the treatment of SH in early pregnancy and the relationship between SH during pregnancy and decidual cell pyroptosis through a rat model. A total of 60 female rats were divided into control group, model group, levothyroxine (L-T4) group, low-dose BAR group (6 g/kg), medium-dose BAR group (12 g/kg), and high-dose BAR group (24 g/kg). The control group underwent pseudothyroidectomy, while the remaining groups established nonpregnant SH rat models. Except for the blank control group, rats were successfully established with SH models during pregnancy. The control group and the model group were treated with saline or BAR. The animals were sacrificed 12 hours after the last administration. The levels of serum thyroid-stimulating hormone (TSH), free thyroxine (FT4), interleukin-1β (IL-1β), and interleukin-18 (IL-18) were detected by enzyme-linked immunosorbent assay (ELISA). Western blot was used to detect the expression of decidual nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome, Caspase-1, and porin family proteins. There was no significant difference in serum FT4 among groups (P>0.05). Compared with the control group, serum TSH, IL-1β, IL-18, and NLRP3, Caspase-1, and gasdermin D (GSDMD) proteins in the decidua of the model group were significantly increased (P<0.05). Compared with the model group, the L-T4 group and the high-dose BAR group could significantly decrease the levels of serum TSH, IL-1β, IL-18, and NLRP3, Caspase-1, and GSDMD in decidual tissue (P<0.05). The medium dose of BAR could significantly decrease the levels of TSH, NLRP3, Caspase-1, and GSDMD (P<0.05), and the low dose group of BAR significantly decreased the levels of TSH, NLRP3, and GSDMD (P<0.05). Among them, the high-dose group of BAR had the best reducing effect on IL-18, NLRP3, Caspase-1, and GSDMD. The decidual cells of SH rats in early pregnancy underwent pyroptosis with a high inflammatory response. BAR could improve TSH level in SH during pregnancy, inhibit decidual cell pyroptosis, and reduce the expression of inflammatory factors.

The SELFI Study: Iodine Excess and Thyroid Dysfunction in Women Undergoing Oil-Soluble Contrast Hysterosalpingography.

Hysterosalpingography (HSG) with oil-soluble contrast medium (OSCM) improves pregnancy rates. However, OSCM has high iodine content and long half-life, leading to potential iodine excess. This work aimed to determine the pattern of iodine excess after OSCM HSG and the effect on thyroid function. A prospective cohort study was conducted of 196 consecutive consenting eligible women without overt hypothyroidism or hyperthyroidism. All completed the study with compliance greater than 95%. Participants underwent OSCM HSG (Auckland, 2019-2021) with serial monitoring of thyrotropin (TSH), free thyroxine (FT4), and urine iodine concentration (UIC) for 24 weeks. The main outcome measure was the development of subclinical hypothyroidism (SCH), defined as a nonpregnant TSH greater than 4 mIU/L with normal FT4 (11-22 pmol/L) in those with normal baseline thyroid function. Iodine excess (UIC ≥ 300 μg/L) was almost universal (98%) with UIC peaking usually by 4 weeks. There was marked iodine excess, with 90% and 17% of participants having UIC greater than or equal to 1000 μg/L and greater than 10 000 μg/L, respectively. Iodine excess was prolonged with 67% having a UIC greater than or equal to 1000 μg/L for at least 3 months. SCH developed in 38%; the majority (96%) were mild (TSH 4-10 mIU/L) and most developed SCH by week 4 (75%). Three participants met the current treatment guidelines (TSH > 10 mIU/L). Thyroxine treatment of mild SCH tended to improve pregnancy success (P = .063). Hyperthyroidism (TSH < 0.3 mIU/L) occurred in 9 participants (5%). OSCM HSG resulted in marked and prolonged iodine excess. SCH occurred frequently with late-onset hyperthyroidism occasionally. Regular thyroid function tests are required for 6 months following this procedure.

No Adverse Effect of Levothyroxine Therapy on Bone Density during the Treatment of Subclinical Hypothyroidism

No Adverse Effect of Levothyroxine Therapy on Bone Density during the Treatment of Subclinical Hypothyroidism

Significance of levothyroxine treatment on serum lipid in pregnant women with subclinical hypothyroidism

BackgroundThere is no consensus reference range for serum lipid levels during pregnancy. The benefit of levothyroxine (L-T4) on serum lipid levels are unclear among pregnant women with subclinical hypothyroidism (SCH).ObjectiveTo determine the recommended reference ranges for serum lipid concentrations during pregnancy and effects of L-T4 treatment on serum lipids in pregnant women with SCH.DesignCohort study.MethodsA analysis of 20,365 women in the first trimester was conducted at Beijing Obstetrics and Gynecology Hospital, Capital Medical University during 2018–2020. After excluding women with adverse pregnancy outcomes, we determined the reference range of serum lipid in the first and third trimesters of pregnancy by using median and quartile to determine appropriate percentiles. Next, we divided into three groups as follows: SCH L-T4 treatment group (n = 319), SCH non-intervention group (n = 103) and the control group(n = 9598).ResultsThe recommended reference range for serum lipids in the first trimester of pregnancy should be: TC < 5.33 mmol/L, TG < 1.73 mmol/L, LDL-C < 3.12 mmol/L and HDL-C > 1.1 mmol/L, and in third trimester of pregnancy should be: TC < 8.47 mmol/L, TG < 4.86 mmol/L, LDL-C < 5.3 mmol/L and HDL-C > 1.34 mmol/L.There are significant differences in TC and LDL-C levels between SCH treatment group and SCH non-intervention Group (P = 0.043, P = 0.046; respectively).ConclusionsWe determine the recommended reference ranges for serum lipid concentrations during pregnancy. TC and LDL-C levels in pregnant women with SCH could improve after L-T4 treatment.

Low-grade systemic inflammation in subclinical hypothyroidism

Background: Hypothyroidism is the deficiency in the production of thyroid hormones to meet the requirements of peripheral tissues. Subclinical hypothyroidism (SCH) is defined biochemically as normal serum free thyroxin concentration in the presence of an elevated serum thyroid-stimulating hormone (TSH) concentration. SCH may be associated with low-grade systemic inflammation (increased high sensitivity-C reactive protein (hs-CRP), one possible explanation may be that TSH in adipocytes promotes the release of interleukin-6 (IL-6). Studies have confirmed inflammatory biomarkers like hs-CRP and IL-6 to be a predictor of cardiovascular (CV) events. However, the treatment of SCH remains subject to debate. Conclusions: It is increasingly evident that SCH has prognostic values and crucial clinical effects, which leads to the view of SCH not being a compensated biochemical change sensu strictu. Even a modest but consistent fluctuation in the circulating thyroid hormone levels can create a response from the human heart. Well-timed treatment should be considered as a precaution to avoid the unfavourable CV diseases. The inflammatory biomarkers, namely CRP and IL-6 are exceptionally robust markers of cardiovascular risk. Thus, using these biomarkers may be helpful in assessing the cardiovascular risk in patients with subclinical hypothyroidism.

The impact of the management strategies for patients with subclinical hypothyroidism on long-term clinical outcomes: An umbrella review.

This umbrella review summarises and compares synthesised evidence on the impact of subclinical hypothyroidism and its management on long-term clinical outcomes. We conducted comprehensive searches on MEDLINE, EMBASE, Scopus, Web of Science, Cochrane Database of Systematic Reviews, JBI Evidence Synthesis, the PROSPERO register, Epistemonikos Database and PDQ Evidence from inception to February and July 2021 using keywords on subclinical hypothyroidism, treatment with levothyroxine, monitoring and primary outcomes (all-cause mortality, cardiovascular events, stroke, frailty fractures and quality of life). Only systematic reviews and meta-analyses on adult patient populations were considered. Study selection, data extraction and quality appraisal using AMSTAR-2 were done independently by two reviewers and discrepancies were resolved through discussion. Overlap across the selected reviews was also assessed, followed by a narrative synthesis of findings. A total of 763 studies were identified from literature searches; 20 reviews met inclusion criteria. Methodological quality ratings were high (n = 8), moderate (n = 7), and low (n = 5), but no reviews were excluded on this basis. Though there was slight overlap across all reviews, some pairwise comparisons had high corrected covered area scores. Compared to euthyroidism, untreated subclinical hypothyroidism was associated with a higher risk of cardiovascular events or death if Thyroid Stimulating Hormone was above 10mIU/L at baseline. Treatment was associated with a lower risk of death from all causes for patients younger than 70 years and possibly better cognitive and quality of life scores than untreated individuals. Evidence on the risk of strokes and fractures was inconclusive. In the long term, treatment of subclinical hypothyroidism may be beneficial for some patient groups. However, the findings of this review are negatively impacted by the relative sparseness and poor quality of available evidence. Additional large and adequately powered studies are needed to investigate this topic further. PROSPERO (CRD42021235172).

Comparison in lipid parameters before and after L-thyroxine treatment in subclinical hypothyroidism according to the presence of thyroid peroxidase antibodies

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