Hypothyroidism and subclinical hypothyroidism in the older patient

Exploring the nexus between hypothyroidism and metabolic dysfunction-associated steatotic liver disease: a UK biobank cohort study

Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease characterised by lipid deposition in liver cells. The global prevalence of NAFLD has significantly increased from 8.2% in 1990 to 30.2% in 2023, establishing it as a growing public health concern. In recent years, the name NAFLD has been replaced by metabolic dysfunction-associated fatty liver disease (MASLD). Numerous observational studies have investigated the potential association between hypothyroidism and MASLD; however, the findings remain inconsistent. In this context, a systematic analysis was conducted to examine the relationship between hypothyroidism and MASLD using data from a large cohort within the UK Biobank. Utilising prospective data from the UK Biobank, a Cox proportional hazards model supplemented with multiple sensitivity analyses was applied to investigate the association between the incidence of hypothyroidism and the onset of MASLD. In addition, stratified analyses and prognostic assessments were performed to assess potential effect modifiers. To explore the underlying mechanisms, mediation analyses were conducted, along with restricted cubic spline regression, to examine potential non-linear relationships and mediation effects within this association. The study found that after fully adjusting for multiple covariates, the risk of MASLD in hypothyroidism patients was 1.711 times that of non-hypothyroidism patients (95% CI 1.560-1.877, P < 0.001). Both subtypes of hypothyroidism, namely non-surgical related hypothyroidism (NSRH) and surgical related hypothyroidism (SRH), were associated with a markedly elevated risk of MASLD onset. For NSRH, the risk is increased by 1.710 times (95% CI 1.557-1.878, P < 0.001), and for SRH, the risk is increased by 1.763 times (95% CI 1.344-2.313, P < 0.001). Stratified analysis revealed an interaction effect between gender and BMI in relation to the risk of MASLD among individuals with NSRH. Mediation analysis revealed the critical role of specific biomarkers in elucidating the relationship between hypothyroidism and MASLD. Notably, red cell distribution width, C-reactive protein, HbA1c, and total protein were identified as significant mediators in this association. Patients with hypothyroidism exhibit a significantly increased risk of developing MASLD, with inflammatory and metabolic markers playing a mediating role in this association. These findings suggest that individuals with hypothyroidism, particularly those with elevated levels of inflammatory markers, may be at heightened risk for MASLD. As such, enhanced clinical monitoring of liver function in these patients is recommended to facilitate early detection and intervention.

Epidemiology of metabolic syndrome and its components in Chinese patients with a range of thyroid-stimulating hormone concentrations

OBJECTIVE

To investigate the relationship between thyroid stimulating hormone (TSH) concentration and the risks of developing metabolic syndrome and its components.

METHODS

A total of 10,140 residents of the Yunyan district of Guiyang (Guizhou, China) who were ≥40 years old were selected by cluster random sampling between May and August 2011, of whom 5692 were eligible. TSH concentration and indices of metabolic syndrome were documented at baseline and 3 years later. Participants were allocated to a euthyroid (TSH 0.55-4.78 mIU/L) or high TSH concentration (TSH >4.78 mIU/L) group. Patients with overt hypothyroidism or were undergoing treatment for hypothyroidism were excluded.

RESULTS

The crude and adjusted prevalences of metabolic syndrome were 39.9% and 33.9% in the euthyroid group and 44.3% and 37.5% in the high TSH group, respectively. Binary logistic regression analysis revealed a positive correlation between a high TSH concentration at baseline and the cumulative incidence of metabolic syndrome during follow up.

CONCLUSIONS

High TSH is associated with a higher risk of developing metabolic syndrome or one of its components; therefore, people with a high TSH concentration should be screened regularly to permit the early identification of metabolic syndrome and followed up thoroughly.

Association between systemic lupus erythematosus and thyroid dysfunction: a meta-analysis

INTRODUCTION

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease, the pathogenesis of which remains elusive. The deficiency or excess of thyroid hormone is defined as thyroid dysfunction, including (subclinical) hypothyroidism and (subclinical) hyperthyroidism. Autoimmune factors are likely to be relevant to the development of SLE and thyroid dysfunction. Recently, many studies have indicated that the prevalence of thyroid dysfunction is higher in SLE patients than in the general population. The objective of our study was to perform a systematic review and meta-analysis to find out the relationship between SLE and thyroid dysfunction.

METHODS

Literature databases were searched, including PubMed, Embase, Web of science, Cochrane, CNKI, CHINESE WANFANG, China Science and Technology Database (VIP). Studies comparing presence of thyroid dysfunction in SLE patients to healthy controls were extracted. All the statistical analyses were performed with STATA 12.0 software.

RESULTS

Ten studies with 10,500 SLE patients and 44,170 healthy controls were included in this study. The meta-analysis results showed that the prevalence of (subclinical) hypothyroidism in SLE patients was higher than in the healthy controls (hypothyroidism: OR = 2.93, 95% CI = 1.81-4.75; subclinical hypothyroidism: OR = 5.67, 95% CI = 3.50-9.18). No statistical difference of (subclinical) hyperthyroidism was found between SLE patients and controls.

CONCLUSION

Our meta-analysis suggests that SLE is significantly associated with increased risk of (subclinical) hypothyroidism, but it has little influence on (subclinical) hyperthyroidism.