Thyroid-stimulating hormone is associated with trabecular bone score and 5-year incident fracture risk in euthyroid postmenopausal women: the OsteoLaus cohort

Association between serum TSH concentration and bone mineral density: an umbrella review

INTRODUCTION

The aim of this study was to summarize the results of previous studies, standardize the data, and present new statistical results in order to provide physicians with clinically significant outcomes regarding the association between serum TSH concentration and bone mineral density (BMD).

METHODS

To perform this umbrella review, a systematic search was conducted in which major online medical databases, such as PubMed, Web of Science, Embase, Scopus, Cochrane Library, and Google Scholar, were searched for meta-analyses and systematic reviews regarding the effect of TSH on BMD. Furthermore, all primary studies were screened for statistical analysis.

RESULTS

The statistical outcomes of the present study were based on the data of 75,898 patients. The pooled risk ratio of any kind of fracture in patients with subclinical hyperthyroidism was estimated to be 1.36 (95% CI: 1.18-1.56; p < 0.001). The SMD for BMD in the distal radius in male patients receiving L-thyroxine suppression therapy was estimated to be -0.61 (95% CI: -1.10-(-0.11); p = 0.02). Furthermore, the pooled risk ratio of any fracture in patients receiving L-thyroxine suppression therapy was estimated to be 1.98 (95% CI: 0.98 - 3.98; p = 0.06). In these patients, the BMD may significantly differ from that in non-treated patients. However, the difference depends on the type of bone.

CONCLUSIONS

Our data confirmed that subclinical hyperthyroidism has a detrimental effect on bones, causing decreased BMD. Based on the obtained results, the authors suggest that a reduced TSH serum level itself may be an individual factor associated with decreased BMD and, thus, with a greater risk of bone fracture. Nevertheless, it should be noted that the effects of TSH suppression therapy differ between areas of interest for assessing BMD. Furthermore, the results have shown that this issue may, in specific areas, concern not only postmenopausal women but also male patients. These conclusions should contribute to a careful consideration of the application of TSH suppressive therapy in all patients. Particular attention should be given to patients after DTC, while all the advantages and disadvantages of implementing L-thyroxine therapy should be individually considered.

Higher serum free thyroxine levels are associated with increased risk of hip fractures in older men

Overt and subclinical hyperthyroidism are associated with an increased fracture risk, but whether thyroid hormones are associated with fracture risk in individuals with normal thyroid-stimulating hormone (TSH) has mostly been investigated in women. Therefore, we investigated if serum levels of free thyroxine (FT4) or TSH are associated with fracture risk in Swedish men. We followed (median 12.2 yr) elderly men (n = 1825; mean age 75, range 69-81 yr) participating in the Gothenburg and Malmö subcohorts of the prospective, population-based MrOS-Sweden study. The statistical analyses included Cox proportional hazards regression. Men receiving levothyroxine treatment were excluded. In our total cohort, serum FT4 (per SD increase) was associated with increased risk of major osteoporotic fractures (MOFs; n = 479; fully adjusted hazard ratio [HR] 1.14, 95% CI, 1.05-1.24) and hip fractures (n = 207; HR 1.18, 95% CI, 1.04-1.33). Also, in men with normal TSH (n = 1658), FT4 (per SD increase) was significantly associated with increased risk of MOF and hip fractures. Furthermore, men in the highest FT4 quartile had a 1.5-fold increase in hip fracture risk compared with men in the three lower FT4 quartiles, both in the total population and in men with normal TSH (fully adjusted: HR 1.45, 95% CI, 1.04-2.02 and HR 1.51, 95% CI, 1.07-2.12, respectively). In contrast, the risk of MOF was not statistically different in the highest FT4 quartile compared with the three lower FT4 quartiles. Finally, serum TSH was not associated with fracture risk after full adjustment for covariates. In conclusion, serum FT4, but not serum TSH, is a predictor of hip fracture risk in elderly Swedish men. Additionally, there was an association between FT4 (per SD increase) and the risk of MOF.

The impact of thyroid function on total spine bone mineral density in postmenopausal women

PURPOSE

Osteoporosis has been a widespread concern for older women, especially postmenopausal women. Thyroid function is crucial for bone metabolism. However, the relationship between thyroid function variation within thyroxine reference range and bone mineral density (BMD) remains ambiguous. The objective of this study was to evaluate the effect of subclinical hypothyroidism or hyperthyroidism on total spinal BMD in postmenopausal women.

METHODS

Based on data from the National Health and Nutrition Examination Survey (NHANES) 2007-2010, multivariable weighted logistic regression was used to evaluate the relationships between total spine BMD and TSH among postmenopausal women aged ≥50.

RESULTS

After accounting for a number of variables, this study discovered that the middle TSH tertile was associated with a decreased probability of osteoporosis. Additionally, the subgroup analysis revealed that postmenopausal women over the age of 65 or people with an overweight BMI had a clearer relationship between total spine BMD and TSH.

CONCLUSION

The total spinal BMD had a positive relationship with thyroid stimulating hormone in postmenopausal women, and that appropriate TSH level (1.38-2.32 mIU/L) was accompanied by higher total spinal BMD.

Update on the clinical use of trabecular bone score (TBS) in the management of osteoporosis: results of an expert group meeting organized by the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO), and the International Osteoporosis Foundation (IOF) under the auspices of WHO Collaborating Center for Epidemiology of Musculoskeletal Health and Aging

PURPOSE

Trabecular bone score (TBS) is a grey-level textural measurement acquired from dual-energy X-ray absorptiometry lumbar spine images and is a validated index of bone microarchitecture. In 2015, a Working Group of the European Society on Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO) published a review of the TBS literature, concluding that TBS predicts hip and major osteoporotic fracture, at least partly independent of bone mineral density (BMD) and clinical risk factors. It was also concluded that TBS is potentially amenable to change as a result of pharmacological therapy. Further evidence on the utility of TBS has since accumulated in both primary and secondary osteoporosis, and the introduction of FRAX and BMD T-score adjustment for TBS has accelerated adoption. This position paper therefore presents a review of the updated scientific literature and provides expert consensus statements and corresponding operational guidelines for the use of TBS.

METHODS

An Expert Working Group was convened by the ESCEO and a systematic review of the evidence undertaken, with defined search strategies for four key topics with respect to the potential use of TBS: (1) fracture prediction in men and women; (2) initiating and monitoring treatment in postmenopausal osteoporosis; (3) fracture prediction in secondary osteoporosis; and (4) treatment monitoring in secondary osteoporosis. Statements to guide the clinical use of TBS were derived from the review and graded by consensus using the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach.

RESULTS

A total of 96 articles were reviewed and included data on the use of TBS for fracture prediction in men and women, from over 20 countries. The updated evidence shows that TBS enhances fracture risk prediction in both primary and secondary osteoporosis, and can, when taken with BMD and clinical risk factors, inform treatment initiation and the choice of antiosteoporosis treatment. Evidence also indicates that TBS provides useful adjunctive information in monitoring treatment with long-term denosumab and anabolic agents. All expert consensus statements were voted as strongly recommended.

CONCLUSION

The addition of TBS assessment to FRAX and/or BMD enhances fracture risk prediction in primary and secondary osteoporosis, adding useful information for treatment decision-making and monitoring. The expert consensus statements provided in this paper can be used to guide the integration of TBS in clinical practice for the assessment and management of osteoporosis. An example of an operational approach is provided in the appendix. This position paper presents an up-to-date review of the evidence base, synthesised through expert consensus statements, which informs the implementation of Trabecular Bone Score in clinical practice.

Association between sensitivity to thyroid hormone indices and osteoporosis in euthyroid patients with type 2 diabetes mellitus

Background

Thyroid hormones are known to regulate bone metabolism and may influence bone mineral density (BMD), as well as the risk of osteoporosis (OP) and fractures in patients with type 2 diabetes mellitus (T2DM). Recently, sensitivity to thyroid hormone indices has been linked with T2DM and OP independently. However, the relationship between thyroid hormone sensitivity and OP in euthyroid T2DM patients has yet to be investigated.

Objectives

The aim of this study was to determine the association between sensitivity to thyroid hormone indices and the risk of OP in euthyroid patients with T2DM.

Design

This study employed a retrospective, cross-sectional design and utilized data acquired from the Cangzhou Central Hospital in China between 2019 and 2020.

Methods

We retrospectively analyzed the data of 433 patients with T2DM for anthropometric measurements, clinical laboratory test results, and BMD. The thyroid-stimulating hormone index, thyrotroph thyroxine resistance index, and thyroid feedback quantile-based index (TFQI) were calculated to determine thyroid hormone sensitivity. Finally, multivariable logistic regression, generalized additive models, and subgroup analysis were performed to detect the association between sensitivity to thyroid hormone indices and the risk of OP in these patients.

Results

We did not observe a statistically significant linear relationship between sensitivity to thyroid hormones indices and OP after covariate adjustment. However, a nonlinear relationship existed between TFQI and the prevalence of OP. The inflection point of the TFQI was at -0.29. The effect sizes (odds ratio) on the left and right of the inflection point were 0.07 [95% confidence interval (CI): 0.01-0.71; p = 0.024] and 2.78 (95% CI: 1.02-7.58; p = 0.046), respectively. This trend was consistent in older female patients with higher body mass index (BMI; 25-30 kg/m2).

Conclusion

An approximate U-shaped relationship was observed between sensitivity to thyroid hormone indices and OP risk in euthyroid patients with T2DM with variations in sex, age, and BMI. These findings provide a new perspective to elucidate the role of thyroid hormones in OP, specifically in patients with T2DM.

Bone quality in endocrine diseases: determinants and clinical relevance

PURPOSE

Bone is one of the main targets of hormones and endocrine diseases are frequent causes of secondary osteoporosis and fractures in real-world clinical practice. However, diagnosis of skeletal fragility and prediction of fractures in this setting could be a challenge, since the skeletal alterations induced by endocrine disorders are not generally captured by dual-energy X-ray absorptiometry (DXA) measurement of bone mineral density (BMD), that is the gold standard for diagnosis of osteoporosis in the general population. The aim of this paper is to review the existing evidence related to bone quality features in endocrine diseases, proposing assessment with new techniques in the future.

METHODS

A comprehensive search within electronic databases was performed to collect reports of bone quality in primary hyperparathyroidism, hypoparathyroidism, hyperthyroidism, hypercortisolism, growth hormone deficiency, acromegaly, male hypogonadism and diabetes mellitus.

RESULTS

Using invasive and non-invasive techniques, such as high-resolution peripheral quantitative computed tomography or DXA measurement of trabecular bone score (TBS), several studies consistently reported altered bone quality as predominant determinant of fragility fractures in subjects affected by chronic endocrine disorders.

CONCLUSIONS

Assessment of skeletal fragility in endocrine diseases might take advantage from the use of techniques to detect perturbation in bone architecture with the aim of best identifying patients at high risk of fractures.

Association between thyroid hormones and skeletal muscle and bone in euthyroid type 2 diabetes patients

Background:

The impact of thyroid hormones within their normal ranges on skeletal muscle and bone in patients with type 2 diabetes mellitus (T2DM) remains unknown. The purpose of this study was to investigate the relationships of thyroid hormones with muscle and bone in euthyroid patients with T2DM.

Methods:

This cross-sectional study included 344 euthyroid T2DM patients. Muscle mass and bone mineral density were measured by dual-energy X-ray absorptiometry. The levels of thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxin (FT4) were measured by electrochemiluminescence immunoassay.

Results:

The results revealed that FT3 was positively correlated with body mass index (BMI) in male patients after age correction. In men, FT4 was negatively correlated with body weight, BMI, total muscle mass, appendicular skeletal muscle mass (ASM), and ASM index (ASMI), while FT3/FT4 was positively correlated with body weight, BMI, total muscle mass, ASM, and ASMI after age correction. In women, FT4 was negatively correlated with ASM and ASMI, while FT3/FT4 was positively correlated with ASM and ASMI after age correction. FT3/FT4 was significantly lower in men with low muscle mass than in those with normal muscle mass. The age-adjusted odds for incident low muscle mass comparing the lowest and highest FT3/FT4 increased in men.

Conclusions:

FT3/FT4 was positively correlated with ASM and ASMI in both men and women. Therefore, FT3/FT4 may be a parameter indicative of low muscle mass in euthyroid men with T2DM.

Effect of Thyroxine and Thyrotropin on Bone Mineral Density in Postmenopausal Women: A Systematic Review

The effect of thyroid hormones on bone mineral density in postmenopausal women has been reported but is not completely established. To better understand this relationship, this systematic review of the reported association, differences, and effects of thyroxine and/or thyrotropin levels on bone mineral density was conducted. An electronic literature search was conducted on MEDLINE, PMC, Google Scholar, Cochrane Library, and Science Direct from inception to April 2022; 20 studies were identified which include five quasi-experimental studies, three community cohort studies, and 12 hospital-based cross-sectional studies. Following an extensive evaluation, it was difficult to conclusively determine the association or effect of thyroxine or thyrotropin levels on bone mineral density in postmenopausal women. It is therefore suggested to conduct additional non-randomized or randomized control studies on this topic for the benefit of postmenopausal women. Particular attention should be given to the adjustment of age, body mass index, smoking status, alcohol consumption, and dietary calcium in future research on this topic for rigorous analysis.