Management of thyroid dysfunctions in the elderly. French Endocrine Society consensus 2019 guidelines. Short version

Thyroid hormone sensitivity and diabetes onset: a longitudinal cross-lagged cohort

Purpose

Thyroid hormones sensitivity is a newly proposed clinical entity closely related with metabolic health. Prior studies have reported the cross-sectional relationship between thyroid hormones sensitivity and diabetes; however, the longitudinal association is unclear to date. We aimed to explore the relationship between impaired thyroid hormone sensitivity at baseline and diabetes onset using a cohort design.

Methods

This study enrolled 7283 euthyroid participants at the first visit between 2008 and 2009, and then annually followed until diabetes onset or 2019. Thyrotropin (TSH), free triiodothyronine (FT3) and free thyroxine (FT4) were measured to calculate thyroid hormone sensitivity by thyroid feedback quantile-based index (TFQI), Chinese-referenced parametric thyroid feedback quantile-based index (PTFQI), thyrotropin index (TSHI), thyrotroph thyroxine resistance index (TT4RI) and FT3/FT4 ratio. Cox proportional hazard model and cross-lagged panel analysis were used.

Results

The mean baseline age was 44.2 ± 11.9 years, including 4170 (57.3%) male. During a median follow-up of 5.2 years, 359 cases developed diabetes. There was no significant association between thyroid hormones sensitivity indices and diabetes onset, and adjusted hazard ratios per unit (95% CIs) were 0.89 (0.65-1.23) for TFQI, 0.91 (0.57-1.45) for PTFQI, 0.95 (0.70-1.29) for TSHI, 0.98 (0.70-1.01) for TT4RI and 2.12 (0.17-5.78) for FT3/FT4 ratio. Cross-lagged analysis supported the temporal association from fasting glucose to impaired thyroid hormones sensitivity indices.

Conclusions

Our findings could not demonstrate that thyroid hormones sensitivity status is a predictor of diabetes onset in the euthyroid population. Elevated fasting glucose (above 7.0 mmol/L) appeared to precede impaired sensitivity indices of thyroid hormones.

Age-specific association between thyroid autoimmunity and hypothyroidism in Chinese adults aged over 65 years: a cross-sectional study

Background

The correlation between thyroid autoimmune (TAI) disease and hypothyroidism in the elderly of different ages remains unclear. This study aimed to investigate the epidemiological characteristics of hypothyroidism, including subclinical hypothyroidism (Shypo) and overt hypothyroidism (Ohypo) in those aged ≥65 years from iodine-adequate areas and reveal the correlation between TAI and hypothyroidism in the elderly of different ages.

Methods

It was a cross-sectional study involving 2,443 subjects aged ≥65 years from two iodine-adequate areas in China by cluster sampling. They were assigned to the 65-69-, 70-79-, and ≥80-year-old age group. All subjects were surveyed by questionnaires and received physical examinations, laboratory testing, and thyroid ultrasound. Epidemiological characteristics of thyroid diseases in the elderly were compared among the three groups. Risk factors for hypothyroidism were predicted by binary logistic regression analysis.

Results

The median urinary iodine level was 238.70 (197.00, 273.70) μg/L. Thyroid peroxidase antibody or thyroglobulin antibody positivity (11.87%) and Shypo (9.13%) were common in the elderly. The prevalence of hypothyroidism in the elderly increases with age. TAI was a risk factor for Shypo (OR, 1.94; 95% CI, 1.35, 2.80; p < 0.01) and Ohypo (OR, 7.64; 95% CI, 3.40, 17.19; p < 0.01) in elderly Chinese. There was an age-specific correlation between TAI and hypothyroidism in the elderly. However, a significant correlation was not identified between TAI and hypothyroidism in ≥80-year-old age group (p > 0.05).

Conclusion

Hypothyroidism, particularly Shypo, is common in the elderly from iodine-adequate areas in China. TAI serves as a risk factor for hypothyroidism in the elderly, with an age-specific correlation with hypothyroidism.

2022 Update on Clinical Management of Graves Disease and Thyroid Eye Disease

The management of hyperthyroidism and extrathyroidal manifestations of Graves disease remains complex. Considerations that include patient preference, age, comorbidity, pregnancy, tobacco smoking, and social determinants of health must all be weaved into a cohesive management plan. A multidisciplinary team is required to manage all aspects of Graves disease, particularly thyroid eye disease, for which new therapeutic options are now available.

Age-specific thyrotropin references decrease over-diagnosis of hypothyroidism in elderly patients in iodine-excessive areas

OBJECTIVE

Acute or chronic exposure to excess iodine has detrimental effects on thyroid physiology; therefore, this study aimed to determine the prevalence of overt hypothyroidism (OH) and subclinical hypothyroidism (SCH) in an elderly population residing in geographical areas with chronic exposure to excess iodine intake and to analyse contributing risk factors.

DESIGN

This cross-sectional study was conducted from 2016 to 2017 in areas of Jiangsu Province that have documented chronic exposure to high iodine intake.

PATIENTS

We enroled 2559 adult participants using a multistage, stratified sampling method.

MEASUREMENTS

Urinary iodine concentration (UIC), serum thyroid-stimulating hormone (TSH) level and other relevant parameters were measured. Demographic information was recorded using a standardized questionnaire. The age-specific TSH references were determined by the National Academy of Clinical Biochemistry guidelines. Univariate and multivariate logistic regression analyses were performed to identify risk factors for hypothyroidism in the study population.

RESULTS

The median UIC of participants was 307.3 µg/L (interquartile range: 200.7, 469.8 μg/L). The prevalence of OH in subjects ≥70 years using laboratory reference ranges was 2.37%; however, it decreased to 1.78% with the use of an age-specific reference range. Similarly, the prevalence of SCH also declined drastically from 29.59% to 2.96% with the application of an age-specific reference range. In both univariate and multivariate models, advanced age, female gender and high UIC were identified as risk factors for hypothyroidism.

CONCLUSIONS

Usage of age-specific TSH reference ranges led to a significantly lower prevalence of OH and SCH in the study population, thus preventing unnecessary over-diagnosis and over-treatment.