Assessment of functional lung impairment in patients with thyroid disorders

Angiopoietin-like proteins 3, 4 and 8 are linked to cardiovascular function in naïve sub-clinical and overt hypothyroid patients receiving levothyroxine therapy

OBJECTIVE

Angiopoietin-like proteins (ANGPTL) 3, 4 and 8 are upcoming cardiovascular biomarkers. Experimental studies showed that thyroid hormones altered their levels. We assessed ANGPTL3, 4 and 8 as predictors of cardiovascular functions among naïve subclinical and naïve overt hypothyroidism (SCH and OH) and altered ANGPTL levels with levothyroxine replacement (LT4) and their association with improved cardiovascular risk factors and cardiovascular function.

DESIGN AND METHODS

The study was a prospective follow-up study that assessed ANGPTL3, 4 and 8 levels, vascular status (flow-mediated dilation% of brachial artery (FMD%), carotid intima-media thickness (CIMT), aortic stiffness index (ASI)), left ventricle (LV) parameters (ejection fraction (EF), myocardial performance index (MPI), and LV mass), well-known cardiovascular risk factors and homeostatic model for the assessment of insulin resistance, at two time points, that is, among naïve SCH, naïve OH, and healthy subjects groups; and at 6 months after achieving the euthyroid state with LT4 by calculating their increased or decreased delta changes (∆↑ or ∆↓) in longitudinal arm among LT4-hypothyroid groups.

RESULTS

Significantly elevated levels of ANGPTL3, 4 and 8 among hypothyroid groups than the healthy subjects were reduced with LT4. Multivariate analysis revealed ANGPTLs as independent predictors of cardiovascular functions and the contributors for ANGPTL level included ANGPTL3 and 4 for impaired FMD%, and ANGPTL8 for LV mass among naïve SCH; ANGPTL3 for EF% and ANGPTL8 for CIMT in naïve OH; ∆↓ANGPTL3 for ∆↓ASI meanwhile ∆↑freeT4 for ∆↓ANGPTL3, ∆↓fasting glucose, ∆↓triglyceride, and ∆↓thyroid peroxidase antibody for ∆↓ANGPTL4 among LT4-SCH. ∆↓ANGPTL4 for ∆↓MPI and ∆↓LV mass, meanwhile ∆↓TSH and ∆↓triglyceride for ∆↓ANGPTL3, ∆↑free T3 and ∆↓HOMA-IR for ∆↓ANGPTL4, and systolic blood pressure and waist circumference for ∆↓ANGPTL8 among LT4-OH.

CONCLUSION

Elevated ANGPTL3, 4 and 8 levels are differentially independent predictors of endothelial and cardiac function and are reduced with LT4 in SCH and OH.

Association between Comorbidities and Preserved Ratio Impaired Spirometry: Using the Korean National Health and Nutrition Examination Survey IV-VI

BACKGROUND

Preserved ratio impaired spirometry (PRISm) patients have more frequent respiratory symptoms and an increased risk of mortality. However, studies on comorbidities in these patients are lacking.

OBJECTIVES

We investigated the association between PRISm and comorbidities using the Korea National Health and Nutrition Examination Survey (KNHANES).

METHOD

This cross-sectional study included participants aged ≥50 years from the KNHANES (2007-2015). Participants who did not undergo spirometry or performed inadequately were excluded. We classified participants into 3 groups according to spirometry: PRISm (forced expiratory volume in one second [FEV1] /forced vital capacity [FVC] ≥ 0.7 and FEV1 <80%), chronic obstructive pulmonary disease (COPD) (FEV1/ FVC <0.7), and normal. Multivariate logistic regression analyses were used to evaluate the risk of comorbidities in the PRISm group compared to that in the normal group.

RESULT

The study included 17,515 participants: 12,777 (73.0%), 1,563 (8.9%), and 3,175 (18.1%) in normal, PRISm, and COPD groups, respectively. After adjustment for known risk factors of each disease, hypertension (adjusted odds ratio [95% confidence interval]; 1.31 [1.14-1.50]), diabetes (1.51 [1.29-1.78]), hypercholesterolemia (1.20 [1.04-1.37]), obesity (1.31 [1.15-1.48]), ischemic heart disease (1.58 [1.13-2.22]), chronic renal disease (2.31 [1.09-4.88]), and thyroid disease (1.41 [1.09-1.83]) risks were significantly higher in the PRISm group than in the normal group. The average number of comorbidities was 2.45 in the PRISm group, which was higher than that in the normal (2.1) and COPD (2.03) groups (p < 0.05).

CONCLUSION

The number of comorbidities was significantly higher in the PRISm group than in others. Hypertension, diabetes, obesity, ischemic heart disease, chronic renal disease, and thyroid disease were associated with PRISm after adjustment for risk factors.

Diaphragmatic ultrasound and pulmonary functions evaluation in thyroid patients: a case-control study

Background

Dyspnea is a frequent symptom among patients with thyroid disorders. However, its actual causative mechanism is not clear. The diaphragm is the main inspiratory muscle and contraction of the diaphragm is essential for breathing, so any disorder that interferes with contractile muscle function can cause diaphragm dysfunction which is associated with dyspnea. The objective of study is to assess the effect of thyroid disorders on diaphragm excursion and thickness.

Results

Diaphragmatic excursion during tidal, deep, and sniff respiration were significantly decreased in patients with thyroid disorder in comparison to control and significantly decreased in hypothyroid patients (right tidal 1.42 ± 0.29, right deep respiration 5.07 ± 0.72, and sniff 2.15 ± 0.26 cm) than hyperthyroid patients (right tidal 1.61 ± 0.34, right deep respiration 5.63 ± 0.50, and sniff 2.67 ± 0.27 cm) and than the control group (right tidal 2.17 ± 0.27, right deep respiration 6.63 ± 0.33, right sniff 2.89 ± 0.19 cm). Diaphragmatic thickness at end tidal inspiration was significantly decreased in patients with thyroid disorder in comparison to control (p value < 0.05). There was negative correlation between diaphragmatic excursion and duration of disease.

Conclusion

Diaphragmatic excursion and thickness are affected in hypothyroidism compared to hyperthyroidism and control groups. There is significant negative correlation between diaphragmatic excursion and duration of disease in patients’ group. Respiratory symptoms are more frequent in hypothyroid patients.

Prospective role of thyroid disorders in monitoring COVID-19 pandemic

COVID-19 pandemic has affected more than 200 countries and 1.3 million individuals have deceased within eleven months. Intense research on COVID-19 occurrence and prevalence enable us to understand that comorbidities play a crucial role in spread and severity of SARS-CoV-2 infection. Chronic kidney disease, diabetes, respiratory diseases and hypertension are among the various morbidities that are prevalent in symptomatic COVID-19 patients. However, the effect of altered thyroid-driven disorders cannot be ignored. Since thyroid hormone critically coordinate and regulate the major metabolism and biochemical pathways, this review is on the potential role of prevailing thyroid disorders in SARS-CoV-2 infection. Direct link of thyroid hormone with several disorders such as diabetes, vitamin D deficiency, obesity, kidney and liver disorders etc. suggests that the prevailing thyroid conditions may affect SARS-CoV-2 infection. Further, we discuss the oxidative stress-induced aging is associated with the degree of SARS-CoV-2 infection. Importantly, ACE2 protein which facilitates the host-cell entry of SARS-CoV-2 using the spike protein, are highly expressed in individuals with abnormal level of thyroid hormone. Altogether, we report that the malfunction of thyroid hormone synthesis may aggravate SARS-CoV-2 infection and thus monitoring the thyroid hormone may help in understanding the pathogenesis of COVID-19.

Spirometry in adult hypothyroid patients: a comparative study

OBJECTIVES

Hypothyroidism adversely affects pulmonary function, which may improve by thyroxine therapy. Limited studies about the effect of hypothyroidism on spirometric parameters in adult patients were conducted in Basra, south of Iraq. Moreover, the effect of thyroxine therapy on spirometric parameters was not covered by these studies. In this study, pulmonary function in adult's hypothyroid patients was evaluated by spirometry to detect any impairment, type of impairment, and to evaluate the effect of thyroxine therapy.

METHODS

A comparative study was conducted in Al-Faiha Specialized Diabetes, Endocrine, and Metabolism Center (FDEMC) in Al-Faiha teaching hospital, Basrah, Iraq. Subjects are divided into four groups: uncontrolled hypothyroid group (n=72), controlled hypothyroid group (n=60), newly diagnosed hypothyroid group (n=52), and control group (n=110). Spirometry was done to all subjects in sitting position, it's repeated at least three times and the best result was recorded.

RESULTS

A significantly (p<0.05) less spirometric parameters and more abnormal pulmonary function test (PFT) were noticed in hypothyroid groups, the reduction were more pronounced in the uncontrolled hypothyroid group. The abnormality in PFT was mostly of restrictive type. A significantly (p<0.05) negative correlation has been found between thyroid-stimulating hormone (TSH) and spirometric parameters, while the correlation of fT4 is significantly (p<0.05) positive with FVC% and FEV%.

CONCLUSION

In hypothyroidism, high TSH and low fT4 are recognized causes of a reduction in spirometric parameters. Therefore, spirometry can be used to detect pulmonary function changes in hypothyroidism.

Effects of levothyroxine on lung inflammation, oxidative stress and pathology in a rat model of Alzheimer's disease

BACKGROUND

In this study, the effect of levothyroxine (L-T4) on tracheal responsiveness, lung inflammation, oxidative stress and pathological features in a rat model of Alzheimer's disease (AD), was evaluated.

METHODS

An animal model of AD was established by intracerebroventricular injection of streptozotocin (STZ) (3 mg/kg) in rats. The rats were then treated for 3 weeks with L-T4 (10 and 100 μg/kg).

RESULTS

In AD animals, tracheal responsiveness to methacholine and ovalbumin (p < 0.05), white blood cell (WBC) count (p < 0.05 to p < 0.01), malondialdehyde (MDA) concentration (p < 0.05) and inflammation score (p < 0.01) were increased, but superoxide dismutase (SOD) activity and total thiol content (for both cases p < 0.05) were decreased compared to the controls. Tracheal responsiveness to methacholine and MDA concentration (p < 0.05) were decreased in AD animals treated with T4 compared to the AD group. Bronchial inflammation in terms of total and some differential WBC in the BALF and inflammatory score, was significantly worsened in AD animals treated with high dose of T4 (p < 0.05 to p < 0.001) compared to the controls.

CONCLUSION

Alzheimer's disease may cause lung inflammation and treatment with low dose of T4 improved MDA level and lung inflammation.