High androgen levels protect against hypothyroidism

Autoimmune Disease in Turner Syndrome in Sweden: An up to 25 Years' Controlled Follow-up Study

CONTEXT

Turner syndrome (TS) is the most common chromosomal aberration in women; it is the result of structural or numeric abnormalities in the X chromosome. Autoimmune hypothyroidism has been recognized as one of the more prominent disorders associated with TS.

OBJECTIVE

This work aimed to study the prevalence of autoimmune diseases in TS.

METHODS

A cross-sectional, longitudinal, 25-year follow-up study was conducted of patients from adult Turner centers at the University Hospitals, Sweden. During 1994 to 2020, a total of 503 women aged 16 to 71 years with TS were evaluated consecutively every fifth year according to national guidelines. A random population sample of women, n = 401, aged 25 to 44 years, from the World Health Organization Monitoring of Trends and Determinants for Cardiovascular Disease (MONICA) project served as controls. Serum thyrotropin, free thyroxine, vitamin B12, antithyroid peroxidase (anti-TPO), and antitransglutaminase antibodies were measured.

RESULTS

Mean follow-up time (years) was 16 ± 7 for patients and 13 ± 1 for controls. From study start, the prevalence increased in TS for hypothyroidism 40% to 58%, vitamin B12 deficiency 5% to 12%, celiac disease 4% to 7%, positive anti-TPO 26% to 41%, and antitransglutaminase antibodies 6% to 8% (P < .0001 vs controls). Type 1 diabetes and Addison disease were rare. The only interrelationship was between hypothyroidism and vitamin B12 deficiency, both in TS and controls. No association between autoimmune disease and karyotype, antecedent growth hormone treatment, or ongoing estrogen hormone replacement, was seen in TS.

CONCLUSION

In women with TS up to older than 80 years, more than half developed hypothyroidism, mainly autoimmune, during follow-up. Awareness of vitamin B12 deficiency and celiac disease throughout life is also recommended in women with TS.

PCOS during the menopausal transition and after menopause: a systematic review and meta-analysis

BACKGROUND

Current knowledge about the consequences of PCOS during the late reproductive years and after menopause is limited.

OBJECTIVE AND RATIONALE

We performed a systematic review and meta-analysis of data on the pathophysiology, clinical manifestations, diagnosis, prognosis, and treatment of women ≥45 years of age-peri- or postmenopausal-with PCOS.

SEARCH METHODS

Studies published up to 15 April 2023, identified by Entrez-PubMed, EMBASE, and Scopus online facilities, were considered. We included cross-sectional or prospective studies that reported data from peri- or postmenopausal patients with PCOS and control women with a mean age ≥45 years. Three independent researchers performed data extraction. Meta-analyses of quantitative data used random-effects models because of the heterogeneity derived from differences in study design and criteria used to define PCOS, among other confounding factors. Sensitivity analyses restricted the meta-analyses to population-based studies, to studies including only patients diagnosed using the most widely accepted definitions of PCOS, only menopausal women or only women not submitted to ovarian surgery, and studies in which patients and controls presented with similar indexes of weight excess. Quality of evidence was assessed using the GRADE system.

OUTCOMES

The initial search identified 1400 articles, and another six were included from the reference lists of included articles; 476 duplicates were deleted. We excluded 868 articles for different reasons, leaving 37 valid studies for the qualitative synthesis, of which 28 studies-published in 41 articles-were considered for the quantitative synthesis and meta-analyses. Another nine studies were included only in the qualitative analyses. Compared with controls, peri- and postmenopausal patients with PCOS presented increased circulating total testosterone (standardized mean difference, SMD 0.78 (0.35, 1.22)), free androgen index (SMD 1.29 (0.89, 1.68)), and androstenedione (SMD 0.58 (0.23, 0.94)), whereas their sex hormone-binding globulin was reduced (SMD -0.60 (-0.76, -0.44)). Women with PCOS showed increased BMI (SMD 0.57 (0.32, 0.75)), waist circumference (SMD 0.64 (0.42, 0.86)), and waist-to-hip ratio (SMD 0.38 (0.14, 0.61)) together with increased homeostasis model assessment of insulin resistance (SMD 0.56 (0.27, 0.84)), fasting insulin (SMD 0.61 (0.38, 0.83)), fasting glucose (SMD 0.48 (0.29, 0.68)), and odds ratios (OR, 95% CI) for diabetes (OR 3.01 (1.91, 4.73)) compared to controls. Women with PCOS versus controls showed decreased HDL concentrations (SMD -0.32 (-0.46, -0.19)) and increased triglycerides (SMD 0.31 (0.16, 0.46)), even though total cholesterol and LDL concentrations, as well as the OR for dyslipidaemia, were similar to those of controls. The OR for having hypertension was increased in women with PCOS compared with controls (OR 1.79 (1.36, 2.36)). Albeit myocardial infarction (OR 2.51 (1.08, 5.81)) and stroke (OR 1.75 (1.03, 2.99)) were more prevalent in women with PCOS than controls, the ORs for cardiovascular disease as a whole, coronary artery disease as a whole, breast cancer and age at menopause, were similar in patients and controls. When restricting meta-analysis to studies in which women with PCOS and controls had a similar mean BMI, the only difference that retained statistical significance was a decrease in HDL-cholesterol concentration in the former and, in the two studies in which postmenopausal women with PCOS and controls had similar BMI, patients presented with increased serum androgen concentrations, suggesting that hyperandrogenism persists after menopause, regardless of obesity.

WIDER IMPLICATIONS

Hyperandrogenism appeared to persist during the late-reproductive years and after menopause in women with PCOS. Most cardiometabolic comorbidities were driven by the frequent coexistence of weight excess and PCOS, highlighting the importance of targeting obesity in this population. However, the significant heterogeneity among included studies, and the overall low quality of the evidence gathered here, precludes reaching definite conclusions on the issue. Hence, guidelines derived from adequately powered prospective studies are definitely needed for appropriate management of these women.

The prevalence of thyroid dysfunction and hyperprolactinemia in women with PCOS

Introduction

Ovulatory dysfunction is usually caused by an endocrine disorder, of which polycystic ovary syndrome (PCOS) is the most common cause. PCOS is usually associated with estrogen levels within the normal range and can be characterized by oligo-/anovulation resulting in decreased progesterone levels. It is suggested that decreased progesterone levels may lead to more autoimmune diseases in women with PCOS. In addition, it is often claimed that there is an association between hyperprolactinemia and PCOS. In this large well-phenotyped cohort of women with PCOS, we have studied the prevalence of thyroid dysfunction and hyperprolactinemia compared to controls, and compared this between the four PCOS phenotypes.

Methods

This retrospective cross-sectional study contains data of 1429 women with PCOS and 299 women without PCOS. Main outcome measures included thyroid stimulating hormone (TSH), Free Thyroxine (FT4), and anti-thyroid peroxidase antibodies (TPOab) levels in serum, the prevalence of thyroid diseases and hyperprolactinemia.

Results

The prevalence of thyroid disease in PCOS women was similar to that of controls (1.9% versus 2.7%; P = 0.39 for hypothyroidism and 0.5% versus 0%; P = 0.99 for hyperthyroidism). TSH levels were also similar (1.55 mIU/L versus 1.48 mIU/L; P = 0.54). FT4 levels were slightly elevated in the PCOS group, although within the normal range (18.1 pmol/L versus 17.7 pmol/L; P < 0.05). The prevalence of positive TPOab was similar in both groups (5.7% versus 8.7%; P = 0.12). The prevalence of hyperprolactinemia was similarly not increased in women with PCOS (1.3%% versus 3%; P = 0.05). In a subanalysis of 235 women with PCOS and 235 age- and BMI-matched controls, we found no differences in thyroid dysfunction or hyperprolactinemia. In according to differences between PCOS phenotypes, only the prevalence of subclinical hypothyroidism was significantly higher in phenotype B (6.3%, n = 6) compared to the other phenotypes.

Conclusion

Women with PCOS do not suffer from thyroid dysfunction more often than controls. Also, the prevalence of positive TPOab, being a marker for future risk of thyroid pathology, was similar in both groups. Furthermore, the prevalence of hyperprolactinemia was similar in women with PCOS compared to controls.

Thyroid diseases and second to fourth digit ratio in Polish adults

The association between second to fourth finger ratio and thyroid diseases is unexplained. There is a possible interaction between prenatal exposition to sex hormone and thyroid functions in the adulthood. The study included 175 adults investigated in Łódź in the central Poland. It consisted of two main parts: a survey including questions about occurrence of thyroid gland dysfunction and anthropometric measurements (body mass and height and length of the second and fourth finger, waist and hip circumferences). The women who had thyroid disease had higher 2D:4D digit ratio (left hand) (mean = 1.004; SD = 0.036) than healthy ones (mean = 0.989; SD = 0.030) (t = − 2105; p = 0.038; d = 0.707). The association between thyroid diseases occurrence and prenatal steroid hormone exposition is noticed. Only females who had thyroid diseases tend to have higher 2D:4D digit ratio, for left hand.

The Imbalance in Th17 and Treg Cells in Polycystic Ovarian Syndrome Patients with Autoimmune Thyroiditis

The ratio of T helper (Th) 17 and T regulatory (Treg) cells in patients with polycystic ovary syndrome complicated with autoimmune thyroiditis (PCOS-AIT) remains unreported. The study aimed to determine the Th17/Treg cell paradigm in PCOS-AIT patients. In peripheral blood mononuclear cells from PCOS patients and controls, the percentages of Th17 and Treg cells were measured by flow cytometry, the mRNA levels of a Th17-related transcription factor (ROR-γt) and a Treg-specific transcription factor (Foxp3) were determined by qRT-PCR, and the levels of Th17-related cytokines and Treg-related cytokines were measured by ELISA. Additionally, to examine the effect of testosterone on the Th17/Treg cell balance in vitro, cultured PCOS-AIT CD4⁺ T cells were treated with 10 μM testosterone for 24 h, and the Th17/Treg cell proportions and expression of Th17/Treg cell-associated transcription factors and cytokines were analyzed by flow cytometry, qRT-PCR, and ELISA. The Th17 cell percentage, Th17/Treg cell ratio, and expression of Th17-related ROR-γt and IL-17 were significantly higher in peripheral blood mononuclear cells from PCOS-AIT patients than in those from controls. In CD4⁺ T cells derived from PCOS-AIT patients, testosterone significantly decreased the Th17 cell percentage, Th17/Treg ratio, mRNA level of ROR-γt, and production of Th17-related cytokines and increased the Treg cell percentage, mRNA level of Foxp3, and secretion of Treg-related cytokines. The Th17/Treg cell imbalance favoring proinflammatory Th17 cells is involved in the pathogenesis of PCOS-AIT. Targeting the Th17/Treg cell axis may have therapeutic potential in the treatment of PCOS-AIT.

Ovarian Reserve and Serum Concentration of Thyroid Peroxidase Antibodies in Euthyroid Women With Different Polycystic Ovary Syndrome Phenotypes

Objective: It has been shown that women with polycystic ovary syndrome (PCOS), as well as Hashimoto's thyroiditis (HT), are characterized by increased incidence of infertility. Serum anti-Müllerian hormone (AMH), which reflects ovarian reserve, is elevated in PCOS women and is decreased in women with HT. The Rotterdam criteria recognize four clinical PCOS phenotypes, i.e., phenotypes A, B, C, and D. The aim of the present study was to investigate the relation between serum concentrations of thyroid peroxidase antibodies (TPOAbs) and ovarian reserve in different PCOS phenotypes. Patients and methods: We examined 141 women with PCOS [phenotype A was diagnosed in 67 (47.5%) women, phenotype B in 30 (21.3%), phenotype C in 28 (19.9%), and phenotype D in 16 (11.3%)] and 88 control subjects of similar age; all women were euthyroid. Serum concentrations of AMH, thyroid-stimulating hormone (TSH), thyroid hormones, and TPOAbs were assessed. Results: We observed positive serum TPOAbs in 21.9% women with PCOS and in 23.9% controls (p = 0.07). We did not find differences in the frequency of detection of positive serum TPOAbs between phenotypes A, B, and C and the control group (p > 0.05). We did not observe a difference in AMH levels between TPOAbs-positive and TPOAbs-negative women, both in the control group and the PCOS women (all p > 0.05). However, serum AMH concentration was markedly higher in the whole PCOS group (p < 0.01) and in phenotype A (p < 0.01) vs. controls when the serum concentration of TPOAbs was negative. In the groups with positive serum levels of TPOAbs, serum concentration of AMH did not differ between PCOS phenotypes and controls (p = 0.23). Additionally, we observed that serum AMH concentration was related to the level of TPOAbs in the PCOS group (r = -0.4, p = 0.02). Conclusions: The frequency of serum detection of positive TPOAbs did not differ between PCOS phenotypes with clinical/biochemical hyperandrogenism and the control group. The observation of the difference in serum AMH between the PCOS and control groups only in TPOAbs negative women together with the inverse relation of TPOAbs with serum AMH only in the PCOS group might suggest that ovarian reserve is influenced by TPOAbs in PCOS.

High androgen levels protect against hypothyroidism

Introduction

Hypothyroidism is a common disorder, appearing mainly in women although less frequently found in women with polycystic ovary syndrome (PCOS). The objective was to test the hypothesis that hyperandrogenism might protect against hypothyroidism.

Material and methods

The data from three prospective follow‐up studies (up to 21 years) and one register study were compared: women with PCOS (Rotterdam criteria), n = 25, women with Turner syndrome, n = 217, a random population sample of women, n = 315, and men, n = 95 (the WHO MONICA study). Findings were to be verified or rejected in all females, n = 553 716, from the same region. The proportion of hypothyroidism was calculated and thyroid peroxidase antibodies (TPO) in serum were measured.

Results

Hypothyroidism at >50 years of age was found in 8% of women with PCOS, 4% in men (PCOS vs. men; ns), 43% of women with Turner syndrome, irrespective of karyotype (p < 0.001 vs. PCOS), and in 17% of postmenopausal women in the population (p < 0.01 vs. PCOS). Elevated TPO were similar in PCOS and women and men in the population but higher in Turner syndrome. Hypothyroidism increased with age in all groups except PCOS women and men. In the register study, hypothyroidism was less common in women with PCOS >25 years (5.5%) than in women without PCOS (6.8%) from the same region (p < 0.01).

Conclusions

Hypothyroidism was less frequently seen in women with PCOS and in men compared with women in the general population and among women with Turner syndrome. This was not explained by altered autoimmunity or the Y‐chromosome. Androgens seem to protect against hypothyroidism.