Thyroid-stimulating hormone levels in euthyroid patients 8 years following bariatric surgery

Background Bariatric surgery (BS) was shown to promote a decline in thyroid-stimulating hormone (TSH) in euthyroid patients with severe obesity in the short-term. Aim of the present study was to assess the effect of weight loss on thyroid function in euthyroid patients in the long-term following different bariatric procedures. Methods In a retrospective cohort study including 135 patients at baseline, thyroid function was assessed at six time points up to 8 years after surgery. Patients were stratified by TSH levels at baseline and divided into two groups to compare the change in TSH at long-time. We used log-linear regression to assess the relation between thyroid hormones and TSH and linear regression analyses to identify variables that were thought to determine TSH and fT3/fT4-ratio as well as their change long-term. Results Over a mean follow-up of 8 years, TSH and fT3/fT4-ratio declined (both p < 0.001). Patients with high-normal TSH showed a greater decline in TSH than those with normal TSH compared to baseline. Thyroid hormones and TSH displayed a negative log-linear correlation at long-term follow-up. Change in TSH at long-time showed a negative correlation with TSH at baseline (B = −0.55; p < 0.001). With regard to type of surgery, there were no significant differences in TSH. Conclusion BS promotes a decline of TSH in euthyroid patients up to 8 years after intervention despite weight regain. The greatest change in TSH was seen among patients with high-normal baseline-TSH. Results of log-linear regression suggest recovery of the pituitary-thyroid axis. Type of surgery did not affect the change in TSH levels over time.

Does foetal gender influence maternal thyroid parameters in pregnancy?

Objective It is unknown if foetal gender influences maternal thyroid function during pregnancy. We therefore investigated the prevalence of thyroid disorders and determined first-trimester TSH reference ranges according to gender. Methods A cross-sectional study involving 1663 women with an ongoing pregnancy was conducted. Twin and assisted pregnancies and l-thyroxine or antithyroid treatment before pregnancy were exclusion criteria. Serum TSH, free T4 (FT4) and thyroid peroxidase antibodies (TPOAb) were measured at median (interquartile range; IQR) 13 (11–17) weeks of gestation. Subclinical hypothyroidism (SCH) was present when serum TSH levels were >3.74 mIU/L with normal FT4 levels (10.29–18.02 pmol/L), and thyroid autoimmunity (TAI) was present when TPOAb were ≥60 kIU/L. Results Eight hundred and forty-seven women were pregnant with a female foetus (FF) and 816 with a male foetus (MF). In women without TAI and during the gestational age period between 9 and 13 weeks (with presumed high-serum hCG levels), median (IQR range) serum TSH in the FF group was lower than that in the MF group: 1.13 (0.72–1.74) vs 1.24 (0.71–1.98) mIU/L; P = 0.021. First-trimester gender-specific TSH reference range was 0.03–3.53 mIU/L in the FF group and 0.03–3.89 mIU/L in the MF group. The prevalence of SCH and TAI was comparable between the FF and MF group: 4.4% vs 5.4%; P = 0.345 and 4.9% vs 7.5%; P = 0.079, respectively. Conclusions Women pregnant with an MF have slightly but significantly higher TSH levels and a higher upper limit of the first-trimester TSH reference range, compared with pregnancies with a FF. We hypothesise that this difference may be related to higher hCG levels in women pregnant with a FF, although we were unable to measure hCG in this study. Further studies are required to investigate if this difference has any clinical relevance.

Are Changes in Thyroid Hormones Associated with Mortality in Non-Thyroidal Illness Syndrome?

Introduction: Non-thyroidal illness syndrome (NTIS) can be defined as afunctional impairment of the hypothalamic-pituitary-thyroid axis accompanied by signs of non-thyroidal disease with changes in thyroid stimulating hormone (TSH), free T3 (fT3) and free T4 (fT4) levels. NTIS and thyroid hormone levels in this syndrome are thought to be related with mortality. This study was performed to evaluate the relationship between hormone levels and mortality in this syndrome. Methods: The 5-year mortality data of patients who were hospitalized in the first 6 months of 2014 and whose thyroid hormone levels could be checked twice within 5 years were evaluated. In our study conducted with 405 patients whose thyroid function tests was repeated, the follow-up period was 5 years. Biochemical parameters including thyroid function tests were sent from all patients. NTIS was defined as a condition in patients with low fT3 levels (<2.5 pg/mL) and TSH levels within the normal range (0.38-5.33 mIU / L). Results: 128 patients died, and the number of surviving patients was 277 during the follow-up period. Positive acute phase reactants such as CRP, sedimentation, ferritin was high and albumin (negative acute phase reactant) and fT3 levels were low in patients who died. In addition, these changes in biochemical values were statistically significant. The mortality rate was increased in patients with low fT3 and high fT4 levels. In the follow-up period, changes in TSH levels were not significantly associated with mortality. Conclusion: Both the decrease in fT3 levels and the increase in fT4 levels can be used as predictors and independent risk factors for long-term mortality risk in chronically ill and hospitalized patients with NTIS.

Prognostic Value of Thyroid Hormone Dysfunction and Age in Septicemic Post-Surgical Patients

Introduction: Critical illness and sepsis are difficult to treat with increasing age because of the poor adaptive physiological system as age progresses. The study tries to identify prognostic markers among thyroid hormones for post-surgical critically ill subjects, who have sepsis, to improve the outcome of patients with increasing age. Methods: Free triiodothyronine (FT3), free thyroxine (FT4) and thyroid stimulating hormone (TSH) were estimated by ARCHITECT immunoassay kits in 127 post-surgical critically ill patients with sepsis. Sequential Organ Failure Assessment (SOFA) score was recorded for each patient. Results: The FT3, FT4 and TSH levels decreased and SOFA score increased with increasing age. Thyroid markers were significantly inversely correlated with age (for FT4 r= -0.616, p<0.0001 and for TSH r= -0.453, p<0.0001), with the strongest correlation between FT3 and age (r=0.674, p<0.0001). A positive correlation was observed between SOFA score and age (r=0.577, p<0.0001). FT3 decreases, SOFA and age increase from improved prognosis to worst prognosis (p<0.0001). Conclusions: FT3 surfaced as a prominent prognostic marker that may be used in predicting the prognosis of post-surgical critically ill geriatric patients with sepsis.

Homeopathic Treatment of Subclinical Hypothyroidism—A Series of 19 Cases

Background Subclinical hypothyroidism (SCH) is a common clinical problem. Controversy surrounds the definition, clinical importance, and need for prompt diagnosis and treatment of the mild form of SCH. Aim The aim of the study was to analyze the evolution of serum thyroid stimulating hormone (TSH) levels after a therapeutic homeopathic intervention in women older than 40 years with SCH. Methods This study is a retrospective series of 19 cases of SCH, with serum TSH levels between 5 and 10 mIU/L, treated exclusively with homeopathic medicines prescribed on an individualized basis. Results Nineteen patients were included according to the inclusion and exclusion criteria. Their mean age was 56 years, they were followed for a mean duration of 69 months, the mean number of serum TSH level measurements was 18, and the intervention was successful for 13 patients. Conclusion The homeopathic therapeutic intervention was successful in 68% of the patients, with serum TSH levels back within the normal range (0.5–5.0 mIU/L).

Mild Anemia May Affect Thyroid Function in Pregnant Chinese Women During the First Trimester

BackgroundPregnant women are often susceptible to anemia, which can damage the thyroid gland. However, compared with moderate and severe anemia, less attention has been paid to mild anemia. The purpose of this study was to evaluate the effect of mild anemia on the thyroid function in pregnant women during the first trimester.MethodsA total of 1,761 women in the first trimester of their pregnancy were enrolled from Shenyang, China, and divided into mild anemia and normal control groups based on their hemoglobin levels. Thyroid-stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) levels were compared between the two groups.ResultsThe TSH levels of pregnant women with mild anemia were higher than those of pregnant women without mild anemia (p &lt; 0.05). Normal control women were selected to set new reference intervals for TSH, FT3, and FT4 levels during the first trimester, which were 0.11–4.13 mIU/l, 3.45–5.47 pmol/l, and 7.96–16.54 pmol/l, respectively. The upper limit of TSH 4.13 mU/l is close to the upper limit 4.0 mU/l recommended in the 2017 American Thyroid Association (ATA) guidelines, indicating that exclusion of mild anemia may reduce the difference in reference values from different regions. Mild anemia was related to 4.40 times odds of abnormally TSH levels (95% CI: 2.84, 6.76) and 5.87 increased odds of abnormal FT3 (95% CI: 3.89, 8.85). The proportion of hypothyroidism and subclinical hypothyroidism in patients with mild anemia was higher than that in those without anemia (0.6% vs. 0, p = 0.009; 12.1% vs. 1.9%, p &lt; 0.001). Mild anemia was related to 7.61 times increased odds of subclinical hypothyroidism (95% CI: 4.53, 12.90).ConclusionsMild anemia may affect thyroid function during the first trimester, which highlights the importance of excluding mild anemia confounding when establishing a locally derived specific reference interval for early pregnancy.

The Many Faces of Elevated TSH: When to Avoid Thyroid Hormone Therapy in Older Adults

We have previously demonstrated that hypothalamic-pituitary-thyroid axis aging is characterized by several distinct patterns. An elevated thyrotropin (TSH) level (mean 5.6mIU/L) with normal free thyroxine (FT4) was present in 75 BLSA participants with at least 3 visits. Twenty-one percent had an historical pattern consistent with primary gland failure, while 13% had a pattern consistent with an HPT response to stressors (aging-adaptation). The remainder had intermediate patterns of change. FT4 &gt;0.92pg/ml identified those in whom TSH elevations occurred with aging-adaptation with a 90.0% sensitivity and 93.8% specificity, indicating no need for therapy. In addition, among 597 participants with stable TSH levels in the reference range, being on thyroid hormone therapy increased mortality risk (IRR=1.8; 95% CI 0.9-2.1). Thus, including FT4 in the diagnostic criteria for hypothyroidism in older adults could target therapy to avoid the potential harm of reversing the aging adaptations in those who do not have true early hypothyroidism.

Delayed follow-up visits and Thyroid-Stimulating Hormone among patients with levothyroxine during the COVID-19 pandemic

Introduction The indirect effects of the COVID-19 pandemic on clinical practice have received great attention, but evidence regarding thyroid disease management is lacking. We aimed to investigate the association between delayed follow-up visits during the pandemic and their serum thyrotropin (TSH) levels among patients being treated with levothyroxine. Methods This study included 25,361 patients who made a follow-up visit as scheduled (n=9,063) or a delayed follow-up visit (&lt;30 days, n=10,909; ≥30 days, n=5,389) during the pandemic (after April 2020) in Japan. We employed modified Poisson models to estimate the adjusted risk ratio (aRR) of TSH &gt;4.5 and &gt;10 mIU/L during the pandemic according to the three types of follow-up visit group (i.e., as scheduled, delayed &lt;30 days, and delayed ≥30 days). The models included age, sex, city of residence, TSH levels, underlying thyroid disease, dose of levothyroxine, and duration of levothyroxine prescriptions. Results The mean age was 52.8 years and females were 88%. Patients who were older and had a higher dose or longer duration of levothyroxine prescriptions were more likely to make a delayed follow-up visit during the pandemic. Changes in TSH were larger among the delayed visit groups than the scheduled visit group. We found increased risks of elevated TSH levels during the pandemic among the delayed visit groups, particularly those with delayed visit ≥30 days (TSH &gt;4.5 mIU/L, aRR [95% CI] =1.72 [1.60-1.85]; and TSH &gt;10 mIU/L, aRR [95% CI] =2.38 [2.16-2.62]). Conclusion A delayed follow-up visit during the COVID-19 pandemic was associated with less well-controlled TSH among patients with levothyroxine.

Diagnostic Re-Evaluation and Potential Predictor Factors of Transient and Permanent Congenital Hypothyroidism in Eutopic Thyroid Gland

Background: The incidence of congenital hypothyroidism (CH) has increased over the years, and many predictors for detecting newborns with transient forms (TCH) as early as possible have been considered. Methods: All newborns diagnosed with primary CH and eutopic gland in the Piedmont region of Italy in the period of January 2014–June 2019 were enrolled and re-evaluated at the age of 2 years. Results: 105 newborns were diagnosed with CH during the study period. Dyshormonogenesis was observed in 55/105. At re-evaluation, we found that 52.7% had permanent CH (PCH), while 47.3% had TCH. Male/female rate, TSH levels at diagnosis, levothyroxine requirement at withdrawal and extra-thyroid congenital malformations rate were higher in the PCH group (p = 0.02, p = 0.009, p = 0.02 and p = 0.01), while fT4 levels at diagnosis were lower (p = 0.03). Sensitivity of 72.4% and specificity of 80.7% for serum TSH above 60 mcUI/mL, sensitivity of 73% and specificity of 72.4% for serum fT4 level below 7.2 pg/mL and sensitivity of 66% and specificity of 68% for drug requirement above 2.25 mcg/kg/day were observed in PCH. Conclusions: Demographic, clinical and hormonal data at diagnosis and levothyroxine requirement during the first two years should be adequately monitored to identify infants who are most likely to discontinue therapy after the age of 24 months.

Postpartum Thyroid Dysfunction in Women With Known and Newly Diagnosed Hypothyroidism in Early Pregnancy

BackgroundHypothyroidism in the first trimester of pregnancy (T1) has great adverse effects on mothers and foetuses. However, few studies have investigated the influence on postpartum thyroid dysfunction. This study aimed to evaluate their long-term effect on postpartum thyroid function within one year after delivery.MethodsIn total, 151 women were recruited from 1496 participants and were classified as newly diagnosed subclinical hypothyroidism (SCH) in T1 (ND-SCH, n=50), previously known SCH before pregnancy (PK-SCH, n=51) and previously known overt hypothyroidism (PK-OH, n=50). Their thyroid functions were dynamically monitored from pre-conception to one-year postpartum.ResultsDuring pregnancy, the first thyroid functions’ test time in T1 were 5-8 gestational weeks. After delivery, the prevalence of postpartum thyroiditis (PPT) was comparable in women with previously known and newly diagnosed hypothyroidism [ND-SCH 62.0% vs PK-SCH 64.7% vs PK-OH 64.0%, P=0.96]. For the ND-SCH group, PPT was significantly related with thyroid-stimulating hormone (TSH) &gt;4.0 mU/L occurring at &lt;8 gestational weeks [OR=8.06, 95% CI, 2.08-31.29] and TSH levels outside 1.0-2.5 mU/L near childbirth [OR=3.73, 95% CI, 1.04-13.41]. For patients with known hypothyroidism before pregnancy (PK-SCH and PK-OH), TSH&gt;2.5 mU/L in T1 [OR=3.55, 95% CI, 1.43-8.81] and TPOAb≥300 μIU/mL [OR=6.58, 95% CI, 2.05-21.12] were associated with PPT. Regardless of whether SCH was diagnosed before pregnancy or in T1, the levothyroxine (LT4) treatment was discontinued at delivery. More than 50% of the patients had to face the hypothyroidism phase of postpartum and restarted LT4 treatment in the first-year follow-up. The logistic regression analysis revealed that TSH elevation occurring at &lt;8 gestational weeks [OR=2.48, 95% CI, 1.09-5.6], TSH levels outside 1.0-2.5 mU/L near childbirth [OR=3.42, 95% CI, 1.45-8.05], and TPOAb≥300 μIU/mL [OR=6.59, 95% CI, 1.79-24.30] were the risk factors.ConclusionTSH elevation at &lt;8 gestational weeks was associated with PPT after delivery in women with known and newly diagnosed hypothyroidism. Especially for SCH patients who stopped LT4 treatment at delivery, unsatisfactory TSH level at &lt;8 gestational weeks and near childbirth, TPOAb≥300 μIU/mL were the risk factors for LT4 retreatment in one-year postpartum.