Non-thyroidal disease syndrome in patients with systemic lupus erythematosus: relation to disease inflammatory activity

OBJECTIVE

To identify risk factors for the development of non-thyroidal illness syndrome (NTIS) in patients with systemic lupus erythematosus (SLE).

METHODS

A retrospective analysis of 517 SLE patients and 1034 age-and sex-matched healthy population was conducted to compare the prevalence of NTIS in these two groups, and to analyze the laboratory and clinical characteristics of SLE patients with NTIS. Finally Logistic regression analysis was used to determine the risk factors for NTIS in SLE patients.

RESULTS

The prevalence of NTIS in the SLE patients was significantly higher than that in controls (39.7% vs. 1.0%, P < 0.001). In SLE patients, compared with euthyroidism patients, NTIS patients exhibited higher levels of neutrophils, hepatic enzymes, kidney damage markers, inflammatory markers and SLE disease activity index (SLEDAI). They also had a higher incidence of organ insufficiency and positive antibodies such as anti-ds-DNA antibodies and anti-SSA antibodies. However, NTIS patients had lower levels of hemoglobin, lymphocytes, platelets, serum albumin, and complement. Additionally, NTIS patients had a shorter duration of lupus and lower utilization of disease-modifying antirheumatic drugs (DMARDs) (P < 0.05). Logistic regression analysis showed that elevated SLEDAI (OR = 1.060, 95%CI 1.022-1.099, P = 0.002), elevated systemic immune-inflammation index (SII) (OR = 1.003, 95%CI 1.001-1.007, P = 0.026), elevated erythrocyte sedimentation rate (ESR) (OR = 1.019, 95%CI 1.010-1.028, P < 0.001), and hepatic insufficiency (OR = 1.916, 95% CI 1.173-3.131, P = 0.009) were independent risk factors for the development of NTIS in SLE. DMARDs treatment (OR = 0.495, 95% CI 0.306-0.799, P < 0.001) was an independent protective factor for NTIS.

CONCLUSIONS

Inflammatory activity in SLE patients is associated with the development of NTIS. Key Points • Inflammatory activity indexes such as SLEDAI, SII, and ESR are independent risk factors for NTIS in SLE patients.

Total thyroxine, triiodothyronine, and thyrotropin concentrations during acute nonthyroidal illness and recovery in dogs

BACKGROUND

Acute illness can result in changes in serum total thyroxine (tT4), total triiodothyronine (tT3), and thyrotropin (TSH) concentrations in euthyroid dogs defined as nonthyroidal illness syndrome, but longitudinal evaluation of these hormones during the recovery phase is lacking.

OBJECTIVES

To longitudinally evaluate serum tT4, tT3, and TSH concentrations during the acute phase and recovery from acute illness in dogs.

ANIMALS

Nineteen euthyroid client-owned dogs hospitalized for acute illness at a veterinary teaching hospital.

METHODS

Prospective longitudinal study. Serum tT4, tT3, and TSH concentrations were measured at the admission (T0), at last day of hospitalization (T1), and during the recovery phase at 3, 7, 14, and 21 days after the discharge (T2, T3, T4, and T5), respectively.

RESULTS

tT4 and tT3 were below the reference interval (RI) at T0 in 3 (16%) and 18 (95%) dogs, respectively; tT4 normalized in all dogs early in the recovery phase, while low tT3 persisted at the end of the study in 16 (83%) dogs. Median TSH concentrations were increased at T5 compared with T1 (0.19 ng/mL [range 0.03-0.65] vs 0.11 ng/mL [range (0.05-0.26)], mean difference = 0.09 ng/mL; P = .03). Five (26%) dogs had TSH above the RI at least at 1 time point during the recovery phase. None of the dogs had concurrent low tT4 and high TSH during the study.

CONCLUSIONS AND CLINICAL RELEVANCE

In euthyroid dogs acute illness can interfere with evaluation of thyroid function up to 21 days during the recovery phase. Thyroid testing should be avoided or postponed in these dogs.

Analysis of clinical features and 7-year all-cause mortality in older male patients with non-thyroidal illness syndrome on general wards

PURPOSE

Older patients with non-thyroidal illness syndrome (NTIS) have a poor prognosis. However, there are few studies on the association of NTIS and mortality among older inpatients on general wards. In a 7-year retrospective observational study, we aimed to investigate the clinical features of NTIS and the association of NTIS and all-cause mortality in older inpatients.

METHODS

A total of 959 older male inpatients whose average age was 86.3 ± 8.1 years were enrolled and divided into the NTIS group and non-NTIS group. Cox models were performed to explore the association of thyroid hormone level and mortality.

RESULTS

Patients had more respiratory disease and chronic kidney disease in the NTIS than in the non-NTIS group, especially in primary nursing care, respiratory failure and haemodialysis patients; serum total protein, albumin, prealbumin, haemoglobin, uric acid and high-density lipoprotein cholesterol levels were lower, and urea nitrogen and fasting blood glucose levels were higher, in the NTIS than in the non-NTIS group. Patients in the NTIS group had a lower survival rate over 7 years follow-up (P < 0.01). A lower free T₃ level was associated with all-cause mortality with a HR of 1.50 (1.36, 1.66). Lower free T₄ level was associated with reduced all-cause mortality with a HR of 0.91 (0.88, 0.94) even after adjusting for confounding factors (P < 0.01).

CONCLUSIONS

Among older male inpatients, the survival rate was lower in the NTIS group. A reduced free T₃ level with low albumin and Hb levels was associated with all-cause mortality; moreover, a higher free T₄ in the normal range may be a strong predictor for long-term mortality risk in hospitalised older male patients.

Representing performance of horizontal flow treatment wetlands: The Tanks In Series (TIS) and the Plug Flow with Dispersion (PFD) approaches and their application to design

Horizontal flow wetlands have been designed using the so-called P-k-C* approach, which has been largely embraced by the treatment wetlands literature. P is meant to represent the equivalent number of apparent tanks in series (hydraulic factor), but also incorporates the loss of biodegradability as the wastewater undergoes treatment (kinetic factor). For design purposes, literature proposes fixed values of P. The proposal of this paper is to decouple hydraulics from kinetics and use the traditional concept of N or NTIS (number of tanks in series) as a function of geometric relationships of the wetland to be designed, leaving kinetic elements to be dealt with solely by the first-order removal rate coefficient (k). From the literature, a database with 41 wetlands with data from tracer studies was used, and a novel regression-based equation was derived relating N with the ratio length/depth of horizontal wetlands. This equation can be used at the design stage for estimating N and, hence, the output concentration of the pollutant using the traditional structure of the TIS model, with a possible inclusion of background concentration (C*). The paper presents all relevant equations, including those from the plug-flow with dispersion model (PFD), and it is shown how to convert from one hydraulic model to the other, what is also believed to be a novel approach in the treatment wetland literature. Finally, the area-based removal rate coefficients (k_A) proposed by Kadlec and Wallace (2009) for designs of horizontal wetlands treating domestic wastewater based on the P-k-C* approach are converted into k_A values for the TIS model in the paper.

Low free triiodothyronine levels are associated with frail phenotype in hospitalized inpatients with cirrhosis

OBJECTIVE

Frailty is a prevalent complication predicting morbidity and mortality in cirrhosis. However, the association between thyroid hormone levels and frailty in cirrhotics remains elusive. Therefore we aimed to evaluate the relationship between thyroid hormone and frail phenotype in euthyroid patients with cirrhosis.

METHODS

A total of 214 adult cirrhotic inpatients were divided into two groups according to Frailty Index. Concentrations of free triiodothyronine (FT3), free thyroxine (FT4) and thyroid stimulating hormone (TSH) were compared. An analysis of the receiver operating characteristic (ROC) curve was implemented to determine the best cut-off for frailty. Multiple logistic regression was used to assess the association between FT3 and frailty.

RESULTS

ROC analysis indicated that the optimal cut-off to stratify frailty was FT3 <3.03 pmol/L with an area under the curve of 0.673 (95% CI: 0.582-0.764, p = 0.002), sensitivity of 81.8% and specificity of 51.9%. Patients with FT3 <3.03 pmol/L exhibited higher incidence of Child-Pugh class B/C, elevated model for end-stage liver disease score, higher creatinine, lower sodium as well as higher incidence of frailty (23.7 vs 6.0%, p < 0.001). A negative correlation was observed between FT3 values and Frailty Index (r = -0.220, p = 0.001). FT3 remained an independent risk factor for frailty after adjusting for age, Child-Pugh class, creatinine, sodium and alanine aminotransferase.

CONCLUSION

In our current study, FT3 <3.03 pmol/L were significantly associated with increased risk for frailty. Measuring FT3, a readily available biomarker, may be useful for identifying frail phenotype in euthyroid patients with cirrhosis.

COVID-19 and thyroid function: What do we know so far?

Coronavirus disease 2019 (COVID-19) was characterized as a pandemic in March, 2020 by the World Health Organization. COVID-19 is a respiratory syndrome that can progress to acute respiratory distress syndrome, multiorgan dysfunction, and eventually death. Despite being considered a respiratory disease, it is known that other organs and systems can be affected in COVID-19, including the thyroid gland. Thyroid gland, as well as hypothalamus and pituitary, which regulate the functioning of most endocrine glands, express angiotensin-converting enzyme 2 (ACE2), the main protein that functions as a receptor to which SARS-CoV-2 binds to enter host cells. In addition, thyroid gland is extremely sensitive to changes in body homeostasis and metabolism. Immune system cells are targets for thyroid hormones and T3 and T4 modulate specific immune responses, including cell-mediated immunity, natural killer cell activity, the antiviral action of interferon (IFN) and proliferation of T- and B-lymphocytes. However, studies show that patients with controlled hypothyroidism and hyperthyroidism do not have a higher prevalence of COVID-19, nor do they have a worse prognosis when infected with the virus. On the other hand, retrospective observational studies, prospective studies, and case reports published in the last two years reported abnormal thyroid function related to acute SARS-CoV-2 infection or even several weeks after its resolution. Indeed, a variety of thyroid disorders have been documented in COVID-19 patients, including non-thyroidal illness syndrome (NTIS), subacute thyroiditis and thyrotoxicosis. In addition, thyroid disease has already been reported as a consequence of the administration of vaccines against SARS-CoV-2. Overall, the data revealed that abnormal thyroid function may occur during and in the convalescence post-COVID condition phase. Although the cellular and molecular mechanisms are not completely understood, the evidence suggests that the "cytokine storm" is an important mediator in this context. Thus, future studies are needed to better investigate the pathophysiology of thyroid dysfunction induced by COVID-19 at both molecular and clinical levels.

T3 levels and thyroid hormone signaling

The clinical availability of tissue-specific biomarkers of thyroid hormone (TH) action constitutes a "holy grail" for the field. Scientists have investigated several TH-dependent markers, including the tissue content of triiodothyronine (T3)-the active form of TH. The study of animal models and humans indicates that the T3 content varies among different tissues, mostly due to the presence of low-affinity, high-capacity cytoplasmic T3 binding proteins. Nonetheless, given that T3 levels in the plasma and tissues are in equilibrium, T3 signaling is defined by the intracellular free T3 levels. The available techniques to assess tissue T3 are invasive and not clinically applicable. However, the tracer kinetic studies revealed that serum T3 levels can accurately predict tissue T3 content and T3 signaling in most tissues, except for the brain and pituitary gland. This is true not only for normal individuals but also for patients with hypo or hyperthyroidism-but not for patients with non-thyroidal illness syndrome. Given this direct relationship between serum and tissue T3 contents and T3 signaling in most tissues, clinicians managing patients with hypothyroidism could refocus attention on monitoring serum T3 levels. Future clinical trials should aim at correlating clinical outcomes with serum T3 levels.

Thyroid Dysfunction in Patients Admitted in Cardiac Care Unit: Prevalence, Characteristic and Hospitalization Outcomes

Introduction

Cardiovascular disease is one of the main causes of hospital admission and mortality, and thyroid dysfunction increases the risk of developing acute or exacerbation of chronic cardiac conditions. The aim of this study is to investigate the prevalence of thyroid hormone abnormality among patients in the cardiac care unit (CCU) patients and its relation to admission diagnosis, clinical, biochemical data, and hospital-related outcomes.

Methods

We conducted a retrospective cohort observational that included adult patients who were admitted to the CCU. We excluded those with known thyroid dysfunction and those who received amiodarone or IV contrast.

Results

A total of 374 patients with a mean age of 62.7+14.7 years old were included. Ischemic changes were observed in 70.6% of the patients based on the admission diagnosis. In comparison to the non-ischemic group, the ischemic group was more likely to be male (P=0.010), to be active/former smokers (P=0.011), to have diabetes (P=0.009), to have diastolic dysfunction (P=<0.001), to have undergone thrombolysis (P=<0.001), and to have been referred to a tertiary center (P=<0.001). Euthyroidism was observed in 57.8% of the patients based on the thyroid function test at admission. Compared to patients with thyroid dysfunction, those with Euthyroidism were more likely to be active/former smokers (P=0.002), to have lower heart rates (P=0.018), to not have chronic kidney disease (P=0.016), to not have heart failure (P=0.006), to have lower thyroid-stimulating hormone (TSH) levels (P=<0.001), and to have lower tricuspid regurgitation (P=0.042).

Conclusion

Thyroid dysfunction is common among patients admitted to the CCU. Non-significant positive correlations between TSH and hospitalization length, tertiary center referral, 30-day readmission, and in-hospital mortality when adjusting for potential confounders.

Low FT3: a possible marker of frailty in the elderly

Introduction

Frailty is associated with a functional decline of multiple physiological systems, of which they may be a cause or consequence. The objective of the study was to evaluate the prevalence of thyroid hormone modifications in elderly frail subjects and its relationship with frailty.

Study population and methods

An observational study was carried out at the University Hospital “Tor Vergata” in Rome among ambulatory and hospitalized patients. The study population consisted of 112 elderly subjects: 62 were hospitalized following hip fracture and 50 control subjects were outpatients. Participating patients received a multidimensional geriatric evaluation. The Survey of Health, Ageing and Retirement in Europe Frailty Instrument (SHARE-FI) was used to assess the degree of frailty. Thyroid stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) were measured to evaluate thyroid status.

Results

FT3, but not FT4, was significantly correlated with Frailty score, both in patients with hip fracture and in patients from the control group. In the entire study population, FT3 under normal limits is effective in discriminating frail/prefrail subjects from nonfrail subjects.

Discussion

The reduction in serum concentrations of FT3 is a clear manifestation of stress associated with fractures. Numerous preexisting factors, such as the fracture patients’ nutritional status, sarcopenia, disability and comorbidities, which characterize the condition of frailty and influence its pathogenesis, are strongly correlated with FT3 values, suggesting the existence of latent nonthyroidal illness syndrome (NTIS).

Conclusion

We conclude that measuring FT3 can be a useful laboratory parameter in clinical assessment, which can play an important role in identifying vulnerable elderly subjects and in quantifying the condition of frailty.

Is non-thyroidal illness syndrome a predictor for prolonged weaning in intubated chronic obstructive pulmonary disease patients?

INTRODUCTION

Non-thyroidal illness syndrome (NTIS) is considered to be associated with adverse outcomes in intensive care unit (ICU) patients. In this study, we evaluated the association between NTIS and prolonged weaning in chronic obstructive pulmonary disease (COPD) patients admitted to the ICU.

MATERIALS AND METHODS

In total, 125 patients with COPD admitted to our ICU who underwent invasive mechanical ventilation (MV) were enrolled. We collected each patient's baseline characteristics including Acute Physiology and Chronic Health Evaluation (APACHE) II score, body mass index (BMI), and thyroid hormones 24 h after ICU admission. The presence of pulmonary infection was also recorded. The primary outcome was prolonged weaning, defined as patients who failed at least three weaning attempts or required > 7 days of weaning after the first spontaneous breathing trial.

RESULTS

Of the 127 patients studied, 64 had normal thyroid function tests and 61 had NTIS. Patients with NTIS had significantly higher APACHE II scores, prolonged weaning, and pulmonary infection. Patients with NTIS had a higher risk for prolonged weaning (odds ratio, OR = 3.21; 95% CI = 1.31-7.83).The presence of pulmonary infection was also an independent risk factors for prolonged weaning.

CONCLUSIONS

NTIS may be an independent predictor for prolonged weaning in intubated COPD patients.