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Introduction:
Insulin resistance (IR) is a key and early pathogenetic mechanism of cardiometabolic diseases with huge potential if being early detected and mitigated, for lowering the burden of the diseases. Available data are conflicting to what extent adult thyroid dysfunction is associated with IR. Therefore, we aimed to investigate the associa...
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Context 1
... obtained data were used to calculate body mass index (BMI) and HOMA-IR for each participant. Based on their TSH and FT4 levels and the manufacturer's instructions, all subjects were divided into subgroups according to Table 1. None of the included subjects was treated with oral antidiabetic drugs or ...Similar publications
Iodine is essential for normal thyroid function, supporting healthy fetal and child development. Io-dine requirements increase in pregnancy, but many women in regions without salt iodisation have insufficient intakes. We explored associations between iodide intake and urinary iodine concentra-tion (UIC), urinary iodine:creatinine ratio (I:Cr), thyr...
Citations
... In NHANES participants, patients treated with LT4 experienced a 15-20% reduction in circulating T3/T4 ratios and normalizing serum TSH, with 15% of patients unable to achieve normal serum T3 levels 27 . Studies have also shown that pharmacologically reducing the T3/T4 ratio can decrease insulin resistance 28 . ...
In light of research indicating that normal TSH levels do not necessarily reflect clinical euthyroidism in hypothyroid patients, and given the patient dissatisfaction with levothyroxine (LT4) monotherapy, we evaluate the response to weight loss treatment in patients with obesity and primary hypothyroidism who are euthyroid under LT4 therapy, with a focus on weight and metabolic parameters. The retrospective study included 138 subjects with obesity (BMI ≥ 30 kg/m²), 69 women with hypothyroidism on levothyroxine, and 69 age- and BMI-matched women without thyroid disease. Secondary causes of obesity, medications that may affect thyroid functions and metabolic parameters, chronic and oncological disease, pregnancy, TSH outside the reference range, follow-up periods of less than one year, and bariatric surgery were the exclusion criteria. Patients’ characteristics and metabolic responses to weight reduction treatment consisting of calorie restriction, moderate exercise, and metformin if needed were evaluated. TSH and fT4 levels were higher, and fT3 and T3/T4 ratios were lower all within the reference ranges in hypothyroid women. They were less insulin resistant. Both patient’ groups experienced a significant decrease in body weight, BMI, and atherogenic index of plasma (AIP) during the follow-up (p = 0.001). Insulin resistance was not changed. The groups’ body weight, BMI, HOMA-IR, and AIP changes were similar at the end of the study (p = 0.876, p = 0.850, p = 0.555, p = 0.293). The results suggest that achieving euthyroid status via levothyroxine monotherapy in hypothyroid women leads to weight loss responses comparable to those in women with normal thyroid. This supports the effectiveness of current hypothyroidism treatment strategies, emphasizing TSH level normalization, in achieving clinical euthyroidism concerning weight loss outcomes.
... Some studies have shown that insulin positively regulates deiodinase activity [5][6][7][8]. A study including 1425 adults with normal thyroid function showed a positive correlation between insulin levels and FT3/FT4 ratio (r = 0.206, P < 0.001) [9]. However, a study showed that the FT3/FT4 ratio was negatively correlated with serum random insulin levels in patients with type 2 diabetes mellitus (T2DM) [10]. ...
Purpose
Free triiodothyronine (FT3)/ free thyroxine (FT4) ratio is often considered as an indicator of deiodinase activity in the context of multiple diseases. We aimed to investigate the changes in deiodinase activity in growth hormone-secreting pituitary adenoma (GHPA) patients at high levels of growth hormone (GH) / insulin-like growth factor-1 (IGF-1) and analyze related influencing factors.
Methods
A retrospective cross-sectional study was conducted to collect demographic and clinical data of 128 GHPA patients with normal thyroid function from the Department of Endocrinology, Beijing Tiantan Hospital, Capital Medical University during 2015-2022. Pearson correlation test and linear regression analysis were used to analyze the relationship between FT3/ FT4 ratio and GH, IGF-1, insulin-like growth factor binding protein-3 (IGFBP-3), homeostasis model assessment of insulin resistance(HOMA-IR), body mass index (BMI) and age.
Results
1. FT3/FT4 ratio was positively correlated with GH and IGFBP-3, but had no significant correlation with IGF-1. 2. FT3/FT4 ratio was positively correlated with BMI and negatively correlated with age. 3. FT3/FT4 ratio was positively correlated with fasting insulin (FINS) and HOMA-IR, but had no significant correlation with fasting C-peptide (FCP). 4. In multivariate analysis, FT3/FT4 ratio was independently associated with age and BMI.
Conclusion
In GHPA patients, high circulating levels of GH/IGF-1/IGFBP-3 system, high insulin level and elevated BMI may increase the activity of deiodinase, leading to increased peripheral T3 level, which may be a compensation mechanism of the body. Besides, deiodinase activity decreases with age, suggesting that elderly GHPA patients should be alerted to the risk of hypothyroidism.
... FT3 to FT4 ratio (FT3/FT4) can estimate the conversion efficiency of FT4 to FT3, which indirectly reflects the peripheral sensitivity of thyroid hormones. Increasing attention has been paid to the relationship between thyroid hormone sensitivity and metabolic disorders in recent years, and sensitivity to thyroid hormone indices have been proved to be reliable predictors of insulin resistance, type 2 diabetes (T2D), cardiometabolic risk, and disorders of glucose and lipid metabolism [20][21][22]. However, studies investigating the relationship between sensitivity to thyroid hormone indices and OA have not been reported. ...
Objectives
Thyroid hormones play an instrumental role in chondrogenic differentiation and matrix maturation. However, studies investigating the relationship between thyroid function and the risk of osteoarthritis (OA) remain scarce. This study was designed to investigate the correlation between thyroid status and OA from a novel perspective of sensitivity to thyroid hormones.
Methods
The study included 8478 people from the National Health and Nutrition Examination Survey (NHANES) 2007–2010. The sensitivity to thyroid hormone indices included Thyrotroph Thyroxine Resistance Index (TT4RI), Thyroid-stimulating hormone (TSHI), Thyroid Feedback Quantile-based Index (TFQI), and Free Triiodothyronine /Free thyroxine (FT3/FT4), which were calculated based on serum free triiodothyronine (FT3), free thyroxine (FT4), and thyroid stimulating hormone (TSH). Considering the complex survey design and sample weights, we employed multivariate linear regression models and stratified analysis to evaluate the correlation between sensitivity to thyroid hormone indices and OA.
Results
Study results indicated that participants with OA had elevated TT4RI, TSHI, and TFQI levels, and lower FT3/FT4 levels compared to those with non-arthritis. After adjusting for other covariates, FT3/FT4 was negatively associated with the risk of OA (OR = 1.162, 95%CI 1.048–1.478, P = 0.021); (OR = 1.261, 95%CI 1.078–1.623, P = 0.042). In subgroup analyses stratified by gender and BMI, participants with OA had higher TFQI levels compared to those without OA in both genders. (OR = 1.491, 95%CI 1.070–2.077, P = 0.018); (OR = 2.548, 95%CI 1.929–3.365, P < 0.001). The higher TFQI levels were consistently associated with the increased prevalence of OA in the BMI (< 18.5 kg/m²) group after adjusting for different covariates, but not in other BMI groups. In, addition, TFQI performed better than FT3/FT4, TSHI, and TT4RI on ROC analyses for OA prediction.
Conclusions
The levels of FT3/FT4, TSHI, TT4RI, and TFQI are strongly associated with the prevalence of OA, which illustrates the complex correlation between the thyroid system and chondrogenic differentiation. TFQI may be used as a helpful indicator to predict OA and provide novel ideas for the evaluation and treatment of OA.
... FT3 to FT4 ratio (FT3/FT4) can estimate the conversion e ciency of FT4 to FT3, which indirectly re ects the peripheral sensitivity of thyroid hormones. Increasing attention has been paid to the relationship between thyroid hormone sensitivity and metabolic disorders in recent years, and sensitivity to thyroid hormone indices have been proved to be reliable predictors of insulin resistance, type 2 diabetes (T2D), cardiometabolic risk, and disorders of glucose and lipid metabolism [20][21][22]. However, studies investigating the relationship between sensitivity to thyroid hormone indices and OA have not been reported. ...
Objectives:
Thyroid hormones play an instrumental role in chondrogenic differentiation and matrix maturation. However, studies investigating the relationship between thyroid function and the risk of osteoarthritis (OA) remain scarce. This study was designed to investigate the correlation between thyroid status and OA from a novel perspective of sensitivity to thyroid hormones.
Methods:
The study included 8,478 people from the National Health and Nutrition Examination Survey (NHANES) 2007-2010. The sensitivity to thyroid hormone indices included Thyrotroph Thyroxine Resistance Index (TT4RI), Thyroid-stimulating hormone (TSHI), Thyroid Feedback Quantile-based Index (TFQI), and Free Triiodothyronine /Free thyroxine (FT3/FT4), which were calculated based on serum free triiodothyronine (FT3), free thyroxine (FT4), and thyroid stimulating hormone (TSH). Considering the complex survey design and sample weights, we employed multivariate linear regression models and stratified analysis to evaluate the correlation between sensitivity to thyroid hormone indices and OA.
Results:
Study results indicated that participants with OA had elevated TT4RI, TSHI, and TFQI levels, and lower FT3/FT4 levels compared to those with non-arthritis. After adjusting for other covariates, FT3/FT4 was negatively associated with the risk of OA (OR= 1.162, 95%CI: 1.048-1.478, P= 0.021); (OR= 1.261, 95%CI: 1.078-1.623, P= 0.042). In subgroup analyses stratified by gender and BMI, participants with OA had higher TFQI levels compared to those without OA in both genders. (OR= 1.491, 95%CI: 1.070-2.077, P= 0.018); (OR= 2.548, 95%CI: 1.929-3.365, P<0.001). The higher TFQI levels were consistently associated with the increased prevalence of OA in the BMI (<18.5 kg/m²) group after adjusting for different covariates, but not in other BMI groups. In, addition, TFQI performed better than FT3/FT4, TSHI, and TT4RI on ROC analyses for OA prediction.
Conclusions:
The levels of FT3/FT4, TSHI, TT4RI, and TFQI are strongly associated with the prevalence of OA, which illustrates the complex correlation between the thyroid system and chondrogenic differentiation. TFQI may be used as a helpful indicator to predict OA and provide novel ideas for the evaluation and treatment of OA.
Objective
There has been some confusion in earlier research on the connection between thyroid function and polycystic ovary syndrome (PCOS). This research is aimed to probe into the correlation between thyroid condition and the risk of PCOS from a new standpoint of thyroid hormone sensitivity.
Methods
This research comprised 415 females with PCOS from Drum Tower Hospital Affiliated with the Medical School of Nanjing University, and 137 non-PCOS individuals were selected as the normal control. Based on free thyroxine (FT4), free triiodothyronine (FT3), and thyroid-stimulating hormone (TSH), we calculated the thyroid hormone sensitivity indices, which consist of Thyroid Feedback Quantile-based Index (TFQI), Thyroid-stimulating Hormone Index (TSHI), Thyrotroph Thyroxine Resistance Index (TT4RI) and Free Triiodothyronine /Free thyroxine (FT3/FT4). The binary logistic regression model was adopted to investigate the correlation between thyroid hormone sensitivity indices with the risk of PCOS. Pearson or Spearman correlation analysis was employed to explore the association among thyroid-related measures with metabolic parameters in PCOS.
Results
Results of this research showed that females with PCOS had rising TFQI, TSHI, TT4RI, and FT3/FT4 levels compared with the control group. After adjustment for the impact of various covariates, there was no significant correlation between FT3/FT4 and the risk of PCOS; However, the odds ratio of the third and fourth vs. the first quartile of TFQI were 3.57(95% confidence interval [CI]:1.08,11.87) and 4.90(95% CI:1.38,17.38) respectively; The odds ratio of the fourth vs. the first quartile of TSHI was 5.35(95% CI:1.48,19.37); The odds ratio of the second vs. the first quartile of TT4RI was 0.27(95%CI 0.09,0.82). In addition, no significant correlation was observed between thyroid-related measures and metabolic measures in females with PCOS.
Conclusions
A reduction in the sensitivity of central thyroid hormone is closely correlated with a higher risk of PCOS. Further research is necessary to corroborate our findings and the supporting mechanisms.
Objectives
A connection between thyroid hormones (THs) and diverse metabolic pathways has been reported. We evaluated thyroid function and tissue sensitivity to THs in children and adolescents with T1D in comparison to euthyroid controls. Additionally, we investigate whether a relationship exists between sensitivity indices and metabolic parameters.
Methods
A retrospective analysis was conducted on 80 pediatric patients diagnosed with T1D. Clinical parameters, TSH, FT3, FT4, and the presence of MS were documented. Additionally, indices of peripheral sensitivity (FT3/FT4 ratio) and central sensitivity (TSH index, TSHI; TSH T4 resistance index, TT4RI; TSH T3 resistance index, TT3RI) were assessed. Thirty healthy subjects were considered as controls.
Results
The overall prevalence of MS was 7.27 %, with MS identified in 8 out of 80 (10 %) T1D subjects; none of the controls manifested MS (p<0.01). No significant differences were observed in indexes of tissue sensitivity to THs between subjects with or without MS (all p>0.05). Correlations between THs and indexes of THs tissue sensitivity and metabolic parameters in controls and T1D patients were noted.
Conclusions
This study affirms a heightened prevalence of MS in children with T1D compared to controls and underscores the potential role of THs in maintaining metabolic equilibrium.
Obesity is a chronic, relapsing, and progressive disease that leads to negative health consequences. Excessive adiposity frequently coexists with metabolic and nonmetabolic complications, deteriorating health and reducing quality of life and life span. Individuals with obesity are not a homogenous group and can present different obesity phenotypes. The most common obesity phenotypes include: metabolically healthy obese (MHO) and metabolically unhealthy obese (MUO). The latter category involves those with developed metabolic syndrome (MetS) and non-fully-developed metabolic syndrome (pre-MetS). The fundamental factor leading to obesity is imbalance between energy uptake and expenditure. From this perspective the thyroid gland plays the pivotal role in metabolism regulation and obesity development. The thyroid regulates thermogenesis, appetite, and lipids turnover. Clinically, hypothyroid patients have decreased metabolic rate and subsequently experience increase of BMI and excess adiposity. The interaction between the thyroid gland and obesity is bidirectional. Several mechanisms of alteration of the hypothalamus-pituitary-thyroid axis in obesity are proposed. Excessive adiposity and dysfunction of adipose tissue may contribute to the development of thyroid functional and structural impairment, such as autoimmunity, thyroid nodules, and thyroid cancer. The prevalence of certain thyroid disorders in obese individuals is higher than in nonobese subjects and this trend is more pronounced in unhealthy obesity phenotypes. The aim of this mini-review is to present the current knowledge on the interaction between thyroid gland disorders and obesity, with special focus on obesity phenotypes.
Introduction. Hypothyroidism is a common endocrine disorder that affects millions of people worldwide. The diagnosis and monitoring of this condition often rely on thyroid hormone levels, which can be limited in their accuracy. Pentraxin 3 (PTX3) is a protein family that is involved in the innate immune response and is distinguished by its distinct pentameric structure.
Aim. To evaluate the utility of serum PTX3 levels in detecting and monitoring hypothyroidism.
Materials and Methods . A case-control design of the study included 90 participants between the ages of 20 and 50 years. These participants were divided into three groups: overt hypothyroidism (OH), subclinical hypothyroidism (SCH), and a control group of healthy individuals. Anthropometric data, including age, sex, weight, height, body mass index (BMI), and hormonal parameters were measured and recorded for each participant.
Results. Our work demonstrates that serum PTX3 levels were significantly elevated in individuals with hypothyroidism, compared to those with normal thyroid function (p<0.001). Furthermore, PTX3 levels correlated positively with TSH levels (r=0.62, p<0.001) and negatively with T4 levels (r= -0.53, p<0.001).
Conclusion. The findings suggest that serum PTX3 levels can be a useful biomarker for detecting and monitoring hypothyroidism, particularly in cases of SCH. The study’s exclusion criteria made sure that no other systemic illnesses or medication use could have tainted the findings. Therefore, the use of plasma PTX3 levels in hypothyroidism detection and monitoring may prove to be a valuable clinical tool in the future.
Objective:
This study aims to explore the correlation between the free-triiodothyronine (FT3)-to-free-thyroxine (FT4) ratio (FT3/FT4) and diabetic kidney disease (DKD) in patients with type 2 diabetes mellitus (T2DM).
Methods:
This study retrospectively analyzed 1729 patients with T2DM hospitalized in the Department of Endocrinology, Peking University International Hospital, from January 2017 to August 2021, including 1075 males and 654 females. In accordance with the FT3/FT4, the patients were divided into three groups.
Results:
(1) The levels of glycosylated hemoglobin (HbA1c), fasting blood glucose (FBG) and postprandial blood glucose (PBG) among the three groups were significantly different, with the low FT3/FT4 group having the highest HbA1c, FBG and PBG among the three groups (F = 39.39, p < 0.01; F = 27.04, p < 0.01; F = 5.76, p = 0.03; respectively). (2) The proportion of DKD is the highest in the low FT3/FT4 group and the lowest in the high FT3/FT4 group (χ2 = 25.83, p < 0.01). (3) Logistic regression showed that low FT3/FT4 were independent risk factors for DKD (OR = 2.36, 95 CI% 1.63, 3.43; p = 0.01).
Conclusion:
A decrease in the FT3/FT4 is an independent predictor of DKD occurrence in patients with T2DM.
