BACKGROUND: Mild hypothyroidism, including subclinical hypothyroidism (SCH) and isolated maternal hypothyroxinemia (IMH), is fairly common in pregnant women, but its impact on pregnancy outcomes is less clear, especially mild hypothyroidism in late pregnancy.
OBJECTIVE: To evaluate the impact of SCH and IMH in the first and third trimesters, respectively, on obstetric and perinatal outcomes.
METHODS: This large prospective study was conducted at the International Peace Maternity and Child Health Hospital (IPMCH) in Shanghai. 52,027 pregnant women who underwent the first-trimester antenatal screening at IPMCH were consecutively enrolled from January 2013 to December 2016. To evaluate the impact of maternal SCH and IMH in the first trimester on pregnancy outcomes, participants were divided into three groups according to thyroid function in the first trimester: first-trimester euthyroidism group (n= 33,130), first-trimester SCH group (n= 884), and first-trimester IMH group (n= 846). Then, to evaluate the impact of maternal SCH and IMH in the third trimester on pregnancy outcomes, the first-trimester euthyroidism group was subdivided into three groups according to thyroid function in the third trimester: third-trimester euthyroidism group (n= 30,776), third-trimester SCH group (n= 562), and third-trimester IMH group (n= 578). Obstetric and perinatal outcomes, including preterm birth (PTB), preeclampsia, gestational hypertension, gestational diabetes mellitus (GDM), large for gestational age (LGA), small for gestational age, macrosomia, cesarean section, and fetal demise were measured and compared between those in either SCH/IMH group and euthyroid group. Binary logistic regression was used to assess the association of SCH or IMH with these outcomes.
RESULTS: 34,860 pregnant women who had first (weeks 8-14) and third trimester (weeks 30-35) thyrotropin and free thyroxine concentrations available were included in the final analysis. Maternal SCH in the first trimester was linked to a lower risk of GDM (aOR 0.64, 95% CI 0.50-0.82) compared with the euthyroid group. However, third-trimester SCH is associated with heightened rates of PTB (aOR 1.56, 95%CI 1.10-2.20), preeclampsia (aOR 2.23, 95%CI 1.44-3.45), and fetal demise (aOR 7.00, 95%CI 2.07-23.66) compared with the euthyroid group. IMH in the first trimester increased risks of preeclampsia (aOR 2.14, 95% CI 1.53-3.02), GDM (aOR 1.45, 95%CI 1.21-1.73), LGA (aOR 1.64, 95%CI 1.41-1.91), macrosomia (aOR 1.85, 95%CI 1.49-2.31) and cesarean section (aOR 1.35, 95%CI 1.06-1.74), while IMH in the third trimester increased risks of preeclampsia (aOR 2.85, 95%CI 1.97-4.12), LGA (aOR 1.49, 95%CI 1.23-1.81) and macrosomia (aOR 1.60, 95%CI 1.20-2.13) compared with the euthyroid group.
CONCLUSIONS: This study indicates that while first-trimester SCH did not elevate the risk for adverse pregnancy outcomes, third-trimester SCH was linked to several adverse pregnancy outcomes. IMH in the first and third trimesters was associated with adverse pregnancy outcomes, yet the impact varied by trimester. These results suggest the timing of mild hypothyroidism in pregnancy may be pivotal in determining its effects on adverse pregnancy outcomes and underscore the importance of trimester-specific evaluations of thyroid function.

Background Patients with subclinical hypothyroidism (SCH) have a high serum concentration of thyroid-stimulating hormone (TSH), whereas their serum-free thyroxine concentrations are normal. Lipid metabolism is regulated in large part by thyroid hormones. It could be connected to a changed lipid profile. This study aimed to evaluate the relationship between SCH and alterations in the lipid profile. Methodology Data from 99 patients with SCH and 109 euthyroid cases were collected from King Abdulaziz Medical City, Jeddah, Saudi Arabia, from 2016 to 2022. Patients older than 18 years were included in the study. The groups were matched in terms of gender, age, and body mass index. SCH was defined as a TSH value of 4.5 to 10 mIU/L, and normal T4 as 5 to 18 μg/dL. Control cases had a normal TSH ranging from 0.45 to 4.5 mIU/L. The total serum cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, and triglyceride (TG) levels in both groups were examined and the results were recorded. Results In comparison to the control group, SCH patients had greater median glycated hemoglobin (HbA1C) (p = 0.001) and lower median vitamin D levels (p = 0.004) before therapy. Before therapy, SCH patients also showed considerably lower HDL levels and significantly higher LDL and TG levels (p < 0.001). Conclusions There is a substantial correlation between SCH and reduced HDL and vitamin D levels. It was linked to increased TG, LDL, and HbA1c levels. Only vitamin D and LDL were pathologically high. Treatment with levothyroxine raised total and LDL cholesterol levels. Future research should look into the affordability of treating SCH.

Pediatric thyroid nodules (TNs) present a higher malignancy rate compared to adults. We sought to diagnose the frequency and characteristics of TNs in children and adolescents with subclinical hypothyroidism (SH) and their outcomes after levothyroxine (LT4) therapy. A total of 256 children with TNs and SH were followed every semester from 2006 to 2018. All patients were treated with LT4. Clinical and radiologic findings, such as the size and texture of the nodules, were documented. Analysis included one-way ANOVA, Kruskal-Wallis, Chi-square, and Fisher\'s exact tests. After initial LT4 therapy, TNs disappeared in 85.5% and did not reappear throughout follow-up. In 14.5%, TNs remained the same or increased in size, but they decreased after subsequent LT4 administration with an increased dose. Thyroid disease family history (FHTD) was documented in 77.0%. In total, 64.5% developed a goiter, 46.0% exhibited thyroid heterogeneity on ultrasound, 23.4% had positive Anti-Tg, and 25.4% had positive anti-TPO autoantibodies. Our findings support the possible premise that early pharmacologic intervention with LT4 may be beneficial in children and adolescents with TNs and SH. The increased frequency of FHTD, goiter, thyroid heterogeneity, and Hashimoto in our patients emphasizes that thyroid ultrasounds may be warranted in children and adolescents with these characteristics in order to rule out the presence of TNs.

Background Subclinical hypothyroidism (SCH) is characterized by elevated thyroid-stimulating hormone (TSH) levels, while thyroid hormones (free thyroxine (T4) and free triiodothyronine (T3)) remain within the reference ranges. Vitamin B12 (cobalamin) deficiency is common in patients with autoimmune disorders, including autoimmune hypothyroidism. The study was aimed at evaluating serum vitamin B12 levels and holotranscobalamin (HoloTC) levels in SCH patients and ascertaining their association with a risky level of TSH and the positivity of anti-thyroid peroxidase (anti-TPO) antibodies. Methodology A case-control study was conducted at Azadi Teaching Hospital, Duhok, a city in the Kurdistan region of Iraq, involving 153 participants, including 72 newly diagnosed SCH patients and 81 healthy controls. Serum levels of vitamin B12, HoloTC, TSH, free T4, free T3, and anti-TPO antibodies were measured based on different principles. Results The mean age of patients with SCH was 32.87±8.7 years, with predominantly females comprising 75% and 77.8% being less than 40 years of age. Moreover, the mean levels of serum TSH (6.96±2.68 µIU/L), anti-TPO antibodies (53.31±81.32 IU/ml), and HoloTC (41.93±19.42 pmol/l) were significantly higher in patients with SCH compared to healthy control participants (p < 0.05), whereas there was a non-significantly higher level of vitamin B12(320.72±98.42 pg/ml) among SCH patients compared to healthy control participants (p = 0.220). The mean levels of vitamin B12 (345.33±103.22 pg/ml) and HoloTC (40.14±18.16 pmol/l) were insignificantly lower in SCH patients with TSH levels more than 7 µIU/L (p > 0.05), as well as the mean levels of vitamin B12 (308.82±96.12 pg/ml) and HoloTC (41.14±19.29 pmol/l) insignificantly lower in SCH patients with positive anti-TPO antibodies (p > 0.05).  Conclusions This study highlights the potential association between SCH and altered vitamin B12 status, particularly evident in HoloTC levels. The presence of positive anti-TPO antibodies and the degree of elevation in TSH levels may exacerbate vitamin B12 deficiency in SCH patients.

BACKGROUND: This study aimed to investigate sex differences in risk factors for suicide attempts in first-episode and drug naive (FEDN) major depressive disorder (MDD) with comorbid subclinical hypothyroidism (SCH).
METHODS: A total of 1034 FEDN MDD patients with comorbid SCH were enrolled. The Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale (HAMA), and Positive and Negative Syndrome Scale (PANSS) positive subscale were used to assess patients\' symptoms. Thyroid hormone levels and metabolic parameters were measured.
RESULTS: MDD patients with SCH had a significantly higher risk of suicide attempts than those without SCH (25.4% vs. 12.2%). Logistic regression showed that HAMA score, thyroid stimulating hormone (TSH) levels, and thyroid peroxidase antibody (TPOAb) levels were significantly associated with an increased risk for suicide attempts in both male and female MDD patients comorbid SCH, while low-density lipoprotein cholesterol (LDL-C) was significantly associated with an increased risk for suicide attempts only in male patients, HAMD score and systolic blood pressure were significantly associated with an increased risk for suicide attempts only in female patients.
CONCLUSIONS: SCH comorbidities may increase suicide attempts in MDD patients. Our results showed significant sex differences in clinical and metabolic factors associated with suicide attempts among FEDN MDD patients with comorbid SCH, highlighting appropriate sex-based preventive interventions are needed.

UNASSIGNED: Polycystic ovary syndrome (PCOS) and subclinical hypothyroidism (SCH) are prevalent gynecological conditions. However, the interrelationship between the two remains elusive. This study aims to elucidate the association between these conditions and determine the potential impact of SCH on the physiological and metabolic characteristics of patients with PCOS.
UNASSIGNED: This cross-sectional study enrolled 133 patients with PCOS from our Hospital. Participants were categorized into two groups: those with PCOS + SCH (n = 58) and those with PCOS (n = 75). Serum hormonal levels, metabolic markers, ovarian volume, and follicle count were compared between the groups.
UNASSIGNED: There was a significant difference in BMI between the two groups, with a higher prevalence of obesity in the PCOS + SCH group (p = .014). Compared to the PCOS group, patients with PCOS + SCH had significantly higher levels of TSH (p < .001), triglycerides (p = .025), and HOMA-IR (p < .001), while LH levels were significantly lower (p = .048). However, multivariate linear regression analysis revealed that TSH, triglycerides, LH, and HOMA-IR were not determinants for the occurrence of SCH in patients with PCOS. Additionally, there was a notable reduction in follicle count in the left ovary for the PCOS + SCH group compared to the PCOS group (p = .003), and the overall follicle diameter of the PCOS + SCH group was also smaller (p = .010).
UNASSIGNED: SCH may exert effects on the physiological and metabolic profiles of patients with PCOS. Further investigation into the relationship between these disorders is warranted to delineate their clinical implications.

Background Hypothyroidism is a prevalent endocrine disorder associated with dyslipidemia, which increases cardiovascular risk. Our study aimed to estimate the prevalence of dyslipidemia and subclinical hypothyroidism (SCH) and their correlation in a diverse population. Methods A descriptive cross-sectional retrospective analysis was conducted to assess the prevalence of dyslipidemia in patients with SCH. Data were collected over 19 months from the Clinical Biochemistry Department of a Moroccan university hospital. A total of 447 patients were included based on comprehensive lipid profile and thyroid-stimulating hormone (TSH) assessments, and normal free thyroxine (FT4) levels. Lipid profile and TSH measurements followed standardized procedures using the Cobas Roche® 6000 system (Roche Diagnostics Corporation, Indianapolis, USA). Dyslipidemia and SCH were defined according to established thresholds recommended by reputable organizations. Statistical analyses were performed using SPSS version 23.0 (IBM Corp., Armonk, USA) and Microsoft Excel (Microsoft Corporation, Redmond, USA), with significance set at p < 0.05. Results In the total population (447 individuals), the prevalence of dyslipidemia was approximately 42.05% (N = 188), with hypoHDLemia being most prevalent at approximately 31.31% (N = 140). The prevalence of SCH was approximately 12.75% (N = 57), with women constituting approximately 7.6% and men approximately 5.15%. In the euthyroid group 1 (N = 390), the prevalence of dyslipidemia was approximately 40.76% (159 individuals), while in the hypothyroid group 2 (N = 57), it increased to approximately 50.87% (N = 29). Hypertriglyceridemia was more prevalent in Group 2, with a prevalence of approximately 21.05% (N = 12), compared to Group 1, which had a prevalence of approximately 13.84% (N = 54). Additionally, hypoHDLemia was notably higher in Group 2, with a prevalence of approximately 38.59% (N = 22), compared to Group 1, which had a prevalence of approximately 30.25% ( N = 118). The chi-square test revealed a significant association between SCH and dyslipidemia (χ2 = 1.427, p < 0.05). The calculated odds ratio (OR) of 1.5 (p < 0.05) indicates that individuals with SCH are 1.5 times more likely to have dyslipidemia compared to those without SCH. Conclusion In conclusion, our study provides valuable insights into the prevalence of dyslipidemia and its association with SCH in our patient population. We observed a notable prevalence of dyslipidemia among individuals with SCH, characterized by elevated levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C). Importantly, while chi-square tests revealed a significant association between SCH and dyslipidemia, logistic regression analyses did not confirm a statistically significant correlation after adjusting for potential confounders.

BACKGROUND: A substantial majority of women in India report experiencing stress frequently, with a significant number indicating a lack of time for relaxation. Women within a central productive age bracket often report higher stress levels. Chronic stress can lead to the development of autoimmune disorders affecting the thyroid gland.
OBJECTIVE: To evaluate the relationship between perceived stress and thyroid function among apparently normal women of reproductive age.
METHODS: The present study was conducted at the Vijayanagar Institute of Medical Sciences (VIMS) after obtaining clearance from the Institutional Ethical Committee and informed written consent from the participants. One hundred and fourteen working women aged 20-49 who consented to the study and had no personal or family history of medical illness or thyroid disease were randomly selected. Stress levels were measured using a Perceived Stress Scale (PSS), and thyroid parameters (total triiodothyronine [T3], total thyroxine [T4], and thyroid-stimulating hormone [TSH]) in blood samples were assessed by the electrochemical luminescence immunoassay method. Anthropometric parameters such as age and body mass index (BMI), as well as vital parameters like pulse rate and blood pressure, were measured for all participants. A detailed history was also recorded, including marital status, duration of married life, education, number of children, type of family, per capita income, phase of menstrual cycle, and dietary habits.
RESULTS: The Statistical Package for the Social Sciences (SPSS) software version 22.0 was used for statistical analysis. The analysis used Pearson\'s chi-square test, Student\'s t-test, and binary logistic regression. A positive correlation was observed between PSS and TSH (correlation coefficient \"r\" value = 0.060) without a significant p-value. Participants were divided into two groups based on TSH values: those with normal thyroid function (TSH <4.2 international units [IU]) and those with subclinical hypothyroidism (SCH) (TSH >4.2 IU). Both groups had total T3 and T4 levels within the normal reference range. A highly significant difference was observed for age, BMI, TSH, marital status, and duration of married life between women with normal thyroid function and those with SCH. No significant difference was found between the two groups for PSS.
CONCLUSIONS: Both acute and chronic stress affect thyroid function through the hypothalamus-pituitary-thyroid (HPT) axis and the hypothalamus-pituitary-adrenal (HPA) axis. Psychological and physiological stressors induce immune modulations that can lead to autoimmune thyroid diseases, resulting in hypothyroidism.
CONCLUSIONS: The study examined the link between stress and thyroid health in women of childbearing age, revealing a trend where higher stress levels corresponded with increased TSH levels, though not significantly. It also found that older age, higher BMI, and longer duration of marriage were linked to a greater occurrence of SCH. These findings underscore the potential influence of lifestyle factors and stress on thyroid function, suggesting that stress management and demographic factors should be considered in managing thyroid health. For women of reproductive age under high stress, routine monitoring of thyroid function could be beneficial for overall health maintenance.

We report a randomized, multicenter, open-label trial (ClinicalTrials.gov: NCT03096613) to investigate the clinical benefits of levothyroxine (L-T4) administration in subclinical hypothyroidism (SCH) patients with heart failure with reduced ejection fraction (HFrEF). Overall, 117 patients were enrolled and received L-T4 plus standard HFrEF treatment (experimental group, N = 57) or standard HFrEF therapy alone (control group, N = 60). The change of 6-min walk test distance in the experimental group was significantly higher than that in the control group at 24 weeks (70.08 ± 85.76 m vs. 27.73 ± 82.00 m, mean difference [95% confidence interval (CI)] 46.90 [12.90, 80.90], p < 0.001). Improvements in New York Heart Association (NYHA) classification (p = 0.033) and thyroid function were significant. Adverse event incidence was similar between groups (risk ratio [95% CI]: 0.942 1.053 (0.424, 2.616); p = 0.628). L-T4 addition to HFrEF treatment improved activity tolerance, NYHA class, and thyroid function within 6 months, suggesting its potential for combined therapy in HFrEF patients with SCH. Future double-blind, placebo-controlled trials should be performed to confirm these results.

BACKGROUND: The physiological equilibrium of the entire human body\'s metabolism is significantly influenced by thyroid hormones. Subclinical hypothyroidism, which is often concealed, is connected to iron deficiency anemia and various other hematological disorders. We in the current study tried to determine the prevalence and severity of iron deficiency anemia and investigate the correlation of subclinical hypothyroidism with iron deficiency.
METHODS: A total of 100 subjects included in the study were divided into two groups. Group 1 included 50 cases with subclinical hypothyroidism, and Group 2 included 50 healthy age- and sex-matched controls. Hemoglobin (Hb) levels were measured within 24 hours of sample collection using a Sysmex automated cell counter (Kobe, Hyogo, Japan). Thyroid hormones (free triiodothyronine (fT3), free thyroxine (fT4), and thyroid-stimulating hormone (TSH)) were measured.
RESULTS: Out of 50 cases, 48 (96%) have iron deficiency anemia, and 52 (104%) have subclinical hypothyroidism. Among the cases with iron deficiency anemia, 43 (86%) also have subclinical hypothyroidism. There was a negative correlation between thyrotropin (TSH) and Hb levels. Pearson\'s correlation coefficient \"r\" values were -0.86408. The serum ferritin levels of cases were decreased as compared to the healthy controls, and the difference in means for cases and controls in terms of serum ferritin is also statistically significant.
CONCLUSIONS: The prevalence of anemia in subclinical hypothyroidism is significantly elevated, and considering the absence of significant clinical manifestations in the early stages, it is recommended to routinely conduct investigations for early detection, facilitating prompt management. Consequently, our study emphasizes that both overt and subclinical hypothyroidism should be recognized as risk factors for the development of iron deficiency anemia.