Correlation analysis of serum thyroid stimulating hormone with acute cerebrovascular disease

Thyroid hormones and stroke, the gap between clinical and experimental studies

Despite plenty of human studies on changes in thyroid hormones after stroke and some animal studies that assessed the effects of thyroid hormone administration on stroke, conclusive evidence for clinical application is lacking. This review aimed to determine the consistency of the results between clinical and preclinical studies. This article reviewed the PubMed, Embase, web of Knowledge, and Google Scholar databases up to June 2023 using the MeSH terms "stroke, cerebral ischemia, cerebral infarction, brain ischemia, brain infarction, triiodothyronine (T3), tetraiodothyronine (T4), thyroxine (T4), and thyroid hormone". The results of clinical and preclinical studies related to T3 substantially confirm each other. That is, in most human studies lower T3 was associated with poor outcomes, and in experimental studies, T3 administration also had therapeutic effects. However, the results of experimental studies related to T4 could not support those of clinical studies. There seem to be some conflicts between experimental and human studies, especially regarding changes and effects of T4 after stroke. The gap between experimental and clinical studies may lead to non-applicable results, wasting time and money, and unnecessary killing of animals.

Thyroid stimulating hormone correlates with triglyceride levels but is not associated with the severity of acute ischemic stroke in patients with euthyroidism: a cross-sectional study

Background

Growing evidence suggests an association between thyroid stimulating hormone (TSH) and severity of acute ischemic stroke (AIS). However, few studies have ruled out the potential influences of abnormal thyroid hormones when assessing this association. This study aimed to investigate the association between TSH levels and the severity of AIS patients with euthyroidism, and to explore the potential mechanism of TSH on this disease by analyzing the correlation of TSH with lipid profiles.

Methods

This retrospective study consisted of 345 patients with normal T3 and T4 levels admitted for first-ever cerebral ischemic stroke. Baseline data of participant were collecte. Laboratory data, including serum levels of TSH and lipid profiles were measured in our hospital's clinical laboratory on admission. Stroke severity was recorded using the National Institutes of Health Stroke Scale (NIHSS). Associations between TSH levels and disease severity were analyzed with logistic regression analysis. Correlations between TSH and lipid profiles were analyzed with Spearman's rank correlation analysis.

Results

Among the 345 patients with AIS, the median age was 63 years (63±12 years), 106 patients (30.7%) were female, 237 (68.7%) patients were mild-severity and 108 (31.3%) patients were severity. Data analysis showed that higher serum TSH levels were associated with the mild severity of patients with AIS (P=0.042 in Kruskal-Wallis test, P=0.025 in logistic regression analysis, and P=0.044 in multiple logistic regression), but not in AIS patients with euthyroidism (P=0.078, P=0.337, respectively). Furthermore, TSH levels were correlated with triglycerides (TG) levels not only in total patients (r=0.135, P=0.012) but also in the patients with euthyroidism (r=0.133, P=0.018).

Conclusions

TSH levels are associated with the severity of AIS patients, but not in patients with euthyroidism, predicting that stratified management of TSH may be beneficial in patients with AIS. Moreover, TSH levels are correlated with TG levels in patients with AIS.

Subclinical thyroid dysfunction and autoantibodies in acute ischemic and hemorrhagic stroke patients: relation to long term stroke outcome

Background

Data regarding the relation between both subclinical thyroid dysfunction, thyroid autoantibodies and clinical outcomes in stroke patients are limited. This study aimed to evaluate subclinical thyroid dysfunction and thyroid autoantibodies production in acute stroke patients and their relation to long term stroke outcome. We recruited 138 patients who were subjected to thorough general, neurological examination and brain imaging. Blood samples were collected for measurement of levels of serum thyroid function [free tri-iodothyronine (FT3), free thyroxin (FT4), thyroid stimulating hormone (TSH)], thyroid autoantibodies within 48 h after hospital admission. FT4 and TSH after 1 year were done. The stroke severity was assessed at admission by the National Institutes of Health Stroke Scale (NIHSS). The stroke outcome was assessed at 3 months and after 1 year by the modified Rankin Scale (mRS). We divided the patients into two groups according to thyroid autoantibodies (positive and negative groups).

Results

Subclinical hyperthyroidism was found in 23% of patients, and subclinical hypothyroidism in 10% of patients. Euthyroidism was detected in 67% of patients. 34% patients had positive thyroid autoantibody. Positive thyroid autoantibodies were commonly found in those with subclinical hyperthyroidism (28%), followed by subclinical hypothyroidism (21%) and euthyroidism (14%). 73% and 59% of stroke patients had poor outcomes (mRS was > 2) at 3 months and 1 year respectively with no significant difference between ischemic and hemorrhagic stroke patients. In the positive group final TSH level, NIHSS score at admission, and disability at 1 year were significantly higher compared with the negative group. Poor outcome was significantly associated with higher NIHSS score at admission, positive thyroid autoantibodies, subclinical hyperthyroidism, and atrial fibrillation.

Conclusions

Subclinical thyroid dysfunction could be found in stroke patients with positive thyroid autoantibodies. Subclinical hyperthyroidism and thyroid autoantibodies were associated with a poor outcome at 1 year in first-ever acute stroke patients especially in those presented with atrial fibrillation and higher NIHSS score at admission.

Endocrine Dysfunction Following Stroke

Endocrine dysfunction is known to occur after traumatic brain injury. The purpose of this study was to examine the incidence of various endocrine dysfunctions after a stroke. The Taiwan National Health Insurance Research Database (NHIRD) was searched from 2001 to 2011 for patients with a diagnosis of stroke. Stroke patients were matched by diagnosis date, age, and sex to patients without a stroke. Cox proportional hazards regression analyses were performed to compare the incidence of goiter, acquired hypothyroidism, thyroiditis, pituitary dysfunction, and disorders of the adrenal glands between stroke and non-stroke patients. There were 131,951 patients in the stroke group, and 131,951 in the matched non- stroke group (mean age 66.1 ± 14.9 years). Stroke patients had significantly higher risk of acquired hypothyroidism (crude hazard ratio [cHR] = 1.65, 95% confidence interval [CI]: 1.44, 1.90; adjusted hazard ratio [aHR] = 1.65, 95% CI: 1.42, 1.91), pituitary dysfunction (cHR = 2.32, 95% CI: 1.79, 2.99; aHR = 1.92, 95% CI: 1.46, 2.52), and disorders of the adrenal glands (cHR = 1.79, 95% CI: 1.52, 2.12; aHR =1.62, 95% CI: 1.36, 1.92) than non-stroke patients. Pituitary dysfunction and disorders of the adrenal glands were found in both hemorrhagic stroke and ischemic stroke patients, while hypothyroidism was seen in ischemic stroke patients only. No significant association was found for goiter and thyroiditis. In conclusions, stroke survivors have an approximately 2-fold increased risk of developing acquired hypothyroidism, pituitary dysfunction, or disorders of the adrenal glands. These risks should be taken into account in the management of patients who have ischemic or hemorrhagic strokes. Graphical Abstract.