EMAS position statement: Thyroid disease and menopause

Signs and symptoms of vulvovaginal atrophy (VVA) in clinical practice - the possible involvement of thyroid autoimmunity in genitourinary syndrome of menopause (GSM)

BACKGROUND

Thyroid autoimmune disorders (ADs) are common in midlife women and can impact various aspects of health, including sexual function. The effect of thyroid autoimmunity on the clinical manifestations of vulvovaginal atrophy (VVA) remains unclear.

OBJECTIVE

To explore the relationship between thyroid ADs and VVA signs and symptoms in a sample of postmenopausal women.

METHODS

Cross-sectional study including postmenopausal women not using systemic hormone therapy. VVA signs were assessed using the vaginal health index (VHI) and vulvar health index (VuHI); VVA symptoms were rated on a four-point severity scale.

RESULTS

Among 112 women enrolled, 28 had thyroid ADs. A significantly higher percentage of women with thyroid ADs showed vaginal atrophy (75 vs. 45.2%, p < .05). A greater proportion of women with thyroid ADs exhibited vulvar atrophy or both vaginal and vulvar atrophy, though these differences were not statistically significant. Women with thyroid ADs reported significantly higher scores for dryness, burning/itching, irritation/inflammation, and dyspareunia compared to those without it. A higher percentage of women with thyroid ADs experienced severe dyspareunia (45 vs. 20.6%, p < .05), severe burning/itching (33.3 vs. 9.1%, p < .05), and severe stress urinary incontinence (17.9 vs. 3.6%, p < 0.05).

CONCLUSIONS

This study suggests that thyroid ADs may contribute to genital aging, with an apparent greater involvement in vaginal signs of atrophy. Women with thyroid ADs reported more severe VVA symptoms, but specific symptomatological clusters should be investigated in larger samples. Our data support the need to explore further the role of thyroid disorders in VVA.

Associations between age at natural menopause and risk of hypothyroidism among postmenopausal women from the Canadian Longitudinal Study on Aging (CLSA)

Menopause is a key period in women's lives associated with major physiological changes. Early menopausal age has been linked to a range of adverse outcomes. Estrogen has been found to increase levels of thyroid binding proteins in the blood; however, its effect on hypothyroidism is not well investigated. To date limited studies were conducted to investigate the association between age at natural menopause and incidence of hypothyroidism, thus the objective of this study is to investigate the association between age at natural menopause and incidence of hypothyroidism among postmenopausal Canadian women. The study included women from the Canadian longitudinal study on aging that were followed for a 10-year period. Analysis was restricted to naturally postmenopausal women without hypothyroidism prior to menopause. Age at natural menopause was examined using the following categories 40-44, 45-49,50-54 (reference), and ≥55. Survival analysis was utilized to determine time to onset of hypothyroidism. Unadjusted and adjusted multivariable Cox regression models were used to assess the relationship between age at natural menopause and incidence of hypothyroidism. The multivariable Cox regression analysis showed no significant association between age at natural menopause and risk of hypothyroidism.

Application of Thyroid Hormones in Women's Hair for the Non-Invasive Prediction of Graves' Disease

Graves' disease (GD) is an autoimmune disorder that can be difficult to distinguish from other diseases due to symptom similarity. The exacerbation of GD owing to delayed diagnosis is a serious issue, and a novel accessible health screening system is needed. Therefore, this study investigated the association between GD and thyroid hormone levels in women's hair and evaluated the prediction accuracy of this non-invasive type of sample. By optimizing pretreatment and analysis techniques using liquid chromatography-mass spectrometry (LC-MS), free triiodothyronine (FT3) and thyroxine (FT4) could be detected in only 2 mg of hair with high sensitivity. Compared with healthy controls, the thyroid hormone levels in the hair of GD patients were significantly higher in correlation with blood levels. The predictive ability of hair thyroid hormones was analyzed using a receiver operating characteristic (ROC) curve, and the optimal cut-off value was determined via the Youden index. As a result, the area under the curve (AUC) was 0.974 (95% confidence interval (CI): 0.935-1.000) for FT3 and 0.900 (95% CI: 0.807-0.993) for FT4. The cut-off value was 0.133 pg/mg (sensitivity: 91.2%; specificity: 100%; positive predictive value (PPV): 100%; negative predictive value (NPV): 76.9%) for FT3 and 0.067 pg/mg (sensitivity: 70.6%; specificity: 100%; PPV: 100%; NPV: 50.0%) for FT4. Collectively, our new approach offers the possibility of accurately and non-invasively detecting GD using hair samples. Since hair can be stored and transported at room temperature, this system facilitates large-scale screening at locations including hair salons and homes, potentially enabling the early determination of GD outside of medical facilities.

Autoimmune thyroiditis incidence in a large population-based study in northeastern Italy

PURPOSE

An improvement in iodine status in the Veneto region (Italy) in the last decade has been documented. Our aim was to estimate the incidence of autoimmune thyroiditis (AT) in this region over the period 2012-2022.

METHODS

A retrospective population-based study conducted in Veneto using the population registry and administrative health databases. We documented incident hyperthyroidism from 2013 to 2022 to exclude prevalent cases and calculated standardised incidence rates (IR) per 10,000 person-years by age and sex.

RESULTS

We identified 65,379 incident cases (IR: 13.38), 5.44-fold higher in females than in males. IR decreased from 15.86 (95% CI: 15.50, 16.21) in 2013 to 12.35 (95% CI: 12.04, 12.67) in 2022. The decline was evident only in females, with a documented reduction in IR from 27.26 (95% CI: 26.61, 27.91) in 2013 to 20.49 (95% CI: 19.92, 21.07) in 2022 (P = 0.002). The decrease was sharper in females aged 15-54 years (IR from 37.86 (95%CI: 36.79, 38.94) in 2013 to 27.40 (95% CI: 26.44, 28.36) in 2022; P < 0.001) than in those aged ≥55 years (IR from 20.06 (95% CI: 19.13, 20.99) in 2013 to 16.56 (95% CI: 15.78, 17.35) in 2022; P = 0.034). In 2020, an out-of-trend decrease in AT incidence was documented, corresponding with the SARS-CoV-2 pandemic, with a realignment to the trend in the subsequent years.

CONCLUSIONS

A decline in AT was documented in the Veneto region in the last decade, paralleling improvement in the iodine status. The reduction was significant only among females, particularly in reproductive age.

Female Reproductive System and Thyroid Dysfunction: Findings from a 12-Year Follow-Up in the Tehran Thyroid Study

Background: The impact of thyroid dysfunction (TD) on the female reproductive system has been extensively documented. While there is evidence suggesting that alteration in female reproductive status may affect thyroid function, conflicting results have prevented definitive conclusions. This study aimed to investigate the associations of parity, spontaneous abortion (mentioned as abortion throughout this study), and menopause status with the prevalence and incidence of TD. Methods: From the Tehran thyroid study population, 2711 participants were included in the cross-sectional analysis to explore associations between female reproductive status and TD. Overall, 2191 participants with euthyroid were included in the survival study and followed up in 3-year intervals. Multinomial logistic regression was adopted in cross-sectional analysis and multivariable Cox proportional hazard model was used to determine associations between the incidence of TD with parity, abortion, and menopause status, adjusting for age, smoking, body mass index, and thyroid peroxidase antibodies positivity. Results: At the baseline, multiple parities (≥4) were significantly associated with overt hypothyroidism (odds ratio [OR] = 1.12; confidence interval [CI] 1.0-1.26) and subclinical hyperthyroidism (OR = 1.11 [CI 1.03-1.21]). Furthermore, multiple abortions were associated with overt hyperthyroidism (OR = 2.09 [CI 1.02-4.26]). Over the course of the study, multiple parities were significantly associated with the incident subclinical and clinical hypothyroidism. Conversely, a history of abortion was associated with a reduced risk of incident overt hypothyroidism. We found no significant association between menopause status and the prevalence or incidence of either hypothyroidism or hyperthyroidism. Conclusions: Our results suggest that the female reproductive system may be associated with thyroid function. Parity and abortion are associated with the occurrence of TD. A deeper understanding of the underlying mechanisms of the cellular and molecular alterations in signaling cascades during pregnancy is necessary to fully elucidate these associations.