Thyroid function analysis in COVID-19: A retrospective study from a single center

Determining the frequency of thyroid involvement in chest CT scans of COVID-19 patients and its correlation with the severity of lung involvement and survival of patients in 2020

Introduction

This study aimed to determine the frequency of thyroid gland involvement in chest CT scans of patients with COVID-19 admitted to university-affiliated hospitals and assess its relationship with the severity of lung involvement and patient survival in 2020.

Material and methods

In this retrospective cross-sectional study, 1000 PCR-positive patients with COVID-19 who were referred to University-affiliated Hospital in 2020 and had chest CT performed within 72 hours of admission to the hospital were examined. The data was collected by patient file information and CT findings recorded in the PACS system, including thyroid involvement, the severity of lung involvement, and findings related to the death and recovery of patients.

Results

The mean age of the examined patients was 56 years. 525 people (52.5%) were men, and 475 (47.5%) were women. 14% had severe pulmonary involvement, and 9.3% had very severe involvement. Moreover, 15.9 percent of them had deceased. 19.7% had focal thyroid involvement, 14% had diffuse involvement, and 66.3% were healthy subjects. Male gender and older age showed a significant relationship with thyroid gland involvement. The severity of lung involvement, the death rate in patients, and hospitalization in ICU were also significantly related to thyroid gland involvement in patients with COVID.

Discussion and conclusion

This study highlights the importance of considering thyroid-gland involvement in the comprehensive management of COVID-19 patients. Routine screening and monitoring of thyroid-function may facilitate earlier detection and appropriate management of thyroid-related complications, potentially improving clinical outcomes. This study suggests that in COVID-19 infection the monitoring of thyroid function is prudent, particularly in cases of more serious disease.

Role of PCSK9 inhibition during the inflammatory stage of SARS-COV-2: an updated review

The potential role of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition in the management of COVID-19 and other medical conditions has emerged as an intriguing area of research. PCSK9 is primarily known for its impact on cholesterol metabolism, but recent studies have unveiled its involvement in various physiological processes, including inflammation, immune regulation, and thrombosis. In this abstract, the authors review the rationale and potential implications of PCSK9 inhibition during the inflammatory stage of SARS-CoV-2 infection. Severe cases of COVID-19 are characterized by an uncontrolled inflammatory response, often referred to as the cytokine storm, which can lead to widespread tissue damage and organ failure. Preclinical studies suggest that PCSK9 inhibition could dampen this inflammatory cascade by reducing the production of pro-inflammatory cytokines. Additionally, PCSK9 inhibition may protect against acute respiratory distress syndrome (ARDS) through its effects on lung injury and inflammation. COVID-19 has been linked to an increased risk of cardiovascular complications, especially in patients with pre-existing cardiovascular conditions or dyslipidemia. PCSK9 inhibitors are known for their ability to lower low-density lipoprotein (LDL) cholesterol levels by enhancing the recycling of LDL receptors in the liver. By reducing LDL cholesterol, PCSK9 inhibition might protect blood vessels from further damage and lower the risk of atherosclerotic plaque formation. Moreover, PCSK9 inhibitors have shown potential antithrombotic effects in preclinical studies, making them a potential avenue to mitigate the increased risk of coagulation disorders and thrombotic events observed in COVID-19. While the potential implications of PCSK9 inhibition are promising, safety considerations and possible risks need careful evaluation. Hypocholesterolemia, drug interactions, and long-term safety are some of the key concerns that should be addressed. Clinical trials are needed to establish the efficacy and safety of PCSK9 inhibitors in COVID-19 patients and to determine the optimal timing and dosing for treatment. Future research opportunities encompass investigating the immune response, evaluating long-term safety, exploring combination therapy possibilities, and advancing personalized medicine approaches. Collaborative efforts from researchers, clinicians, and policymakers are essential to fully harness the therapeutic potential of PCSK9 inhibition and translate these findings into meaningful clinical outcomes.

The prevalence of thyroid disorders in COVID-19 patients: a systematic review and meta-analysis

OBJECTIVES

To conduct a systematic review and meta-analysis to evaluate the prevalence of thyroid disorders in COVID-19 patients.

DATA SOURCES

Scopus, PubMed, ISI Web of Science, and Google Scholar databases were used in this review. We also consider the results of grey literature.

STUDY SELECTIONS

Cohort, cross-sectional, and case-control studies were included.

DATA EXTRACTION AND SYNTHESIS

The required data were extracted by the first author of the article and reviewed by the second author. The Pooled prevalence of outcomes of interest was applied using the meta-prop method with a pooled estimate after Freeman-Tukey Double Arcsine Transformation to stabilize the variances.

OUTCOMES AND MEASURED

The different thyroid disorders were the main outcomes of this study. The diseases include non-thyroidal illness syndrome, thyrotoxicosis, hypothyroidism, isolated elevated free T4, and isolated low free T4.

RESULTS

Eight articles were included in our meta-analysis(Total participants: 1654). The pooled prevalence of events hypothyroidism, isolated elevated FT4, isolated low FT4, NTIS, and thyrotoxicosis were estimated (Pooled P = 3%, 95% CI:2-5%, I2: 78%), (Pooled P = 2%, 95% CI: 0-4%, I2: 66%), (Pooled P = 1%, 95% CI: 0-1%, I2: 0%), (Pooled P = 26%, 95% CI: 10-42%, I2: 98%), and (Pooled P = 10%, 95% CI: 4-16%, I2: 89%), respectively.

CONCLUSION

Thyroid dysfunction is common in COVID-19 patients, with a high prevalence of non-thyroidal illness syndrome (NTIS) and thyrotoxicosis. Our meta-analysis found a 26% prevalence of NTIS and a 10% prevalence of thyrotoxicosis.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42022312601.

Effects of SARS-CoV-2 infection on hypothyroidism and subclinical hypothyroidism: a meta-analysis

Background

In recent years, the outbreak of COVID-19 caused by SARS-CoV-2 has been witnessed globally. However, the impact of SARS-CoV-2 infection on thyroid dysfunction and subclinical thyroid dysfunction remains unclear. Therefore, this meta-analysis aimed to assess the effects of SARS-CoV-2 infection on thyroid dysfunction and its relationship with the severity of COVID-19.

Methods

We systematically searched databases including PubMed, Willey Library, Embase, Web of Science, CNKI, Wanfang, and VIP. We focused on randomized controlled trials, case-control studies, and cohort studies published between December 2019 and August 2023, examining the association between SARS-CoV-2 infection and hypothyroidism, with a specific emphasis on the severity of the infection. The quality of the research was assessed using the Newcastle-Ottawa Scale (NOS), while statistical analysis was conducted using the meta and metafor packages in R 4.2.1 software.

Results

For the meta-analysis, a total of eight articles were identified based on strict inclusion and exclusion criteria. For the association between SARS-CoV-2 infection and hypothyroidism, three studies (266 samples) comparing TSH levels of COVID-19 and control groups showed no difference in TSH levels [SMD=-0.04,95%CI(-1.22,1.15),P=0.95]. Additionally, two studies examining TT3 (a sample of 176 cases) and two studies examining TT4 (a sample of 176 cases) also showed no difference in TT3 and TT4 between the COVID-19 group and the control group, respectively. However, when evaluating the severity of COVID-19, six studies (565 samples) showed that TSH in the severe group was significantly lower than in the mild group [SMD = -0.55, 95% CI (-0.96, -0.14)], while FT3 was also lower in the severe group [SMD = -0.96, 95% CI (-1.24, -0.67)]. No noticeable differences were observed between the severe and mild groups in their TT3, FT4, and TT4 levels.

Conclusion

SARS-CoV-2 infection may have detrimental effects on thyroid function in individuals with severe symptoms. More research is needed to confirm and explore this relationship.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO, identifier CRD42023486042.

Thyroxine changes in COVID-19 pandemic: A systematic review and meta-analysis

OBJECTIVE

COVID-19 infection may affect thyroid function. However, changes in thyroid function in COVID-19 patients have not been well described. This systematic review and meta-analysis assess thyroxine levels in COVID-19 patients, compared with non-COVID-19 pneumonia and healthy cohorts during the COVID-19 epidemic.

METHODS

A search was performed in English and Chinese databases from inception to August 1, 2022. The primary analysis assessed thyroid function in COVID-19 patients, comparing non-COVID-19 pneumonia and healthy cohorts. Secondary outcomes included different severity and prognoses of COVID-19 patients.

RESULTS

A total of 5873 patients were enrolled in the study. The pooled estimates of TSH and FT3 were significantly lower in patients with COVID-19 and non-COVID-19 pneumonia than in the healthy cohort (P < 0.001), whereas FT4 were significantly higher (P < 0.001). Patients with the non-severe COVID-19 showed significant higher in TSH levels than the severe (I² = 89.9%, P = 0.002) and FT3 (I² = 91.9%, P < 0.001). Standard mean differences (SMD) of TSH, FT3, and FT4 levels of survivors and non-survivors were 0.29 (P= 0.006), 1.11 (P < 0.001), and 0.22 (P < 0.001). For ICU patients, the survivors had significantly higher FT4 (SMD=0.47, P=0.003) and FT3 (SMD=0.51, P=0.001) than non-survivors.

CONCLUSIONS

Compared with the healthy cohort, COVID-19 patients showed decreased TSH and FT3 and increased FT4, similar to non-COVID-19 pneumonia. Thyroid function changes were related to the severity of COVID-19. Thyroxine levels have clinical significance for prognosis evaluation, especially FT3.

Menstrual abnormalities after COVID-19 vaccines: A systematic review

The objective of this systematic review is to give a comprehensive interpretation of menstrual cycle changes after the COVID-19 vaccination. Additionally, it is imperative to assess reports of menstrual changes following vaccination to dispel concerns that COVID-19 vaccines hinder the likelihood of pregnancy in the long run. A literature review was conducted using digital databases to systematically identify the studies reporting any menstrual abnormalities after the COVID-19 vaccine. Detailed patient-level study characteristics including the type of study, sample size, administered vaccines, and menstrual abnormalities were abstracted. A total of 78 138 vaccinated females were included in this review from 14 studies. Of these, 39 759 (52.05%) had some form of a menstrual problem after vaccination. Due to the lack of published research articles, preprints were also included in this review. Menorrhagia, metrorrhagia, and polymenorrhea were the most commonly observed problems and the overall study-level rate of menstrual abnormality ranged from 0.83% to 90.9%. Age, history of pregnancy, systemic side-effects of COVID-19, smoking, and second dose of COVID-19 vaccine were predictors of menstrual problems after vaccination.

Thyroid autoimmunity and SARS-CoV-2 infection: Report of a large Italian series

Since the beginning of the pandemic, numerous risk factors have been associated with SARS-CoV-2 infection and COVID-19 outcomes, such as older age, male sex, and the presence of comorbidities, such as hypertension, obesity, and diabetes. Preliminary data also suggest epidemiological association between SARS-CoV-2 infection and systemic autoimmune disease. For this reason, we investigated if patients affected by autoimmune thyroid disorders (AITD) are at risk of developing SARS-CoV-2 infection or COVID-19 disease.

From April to September 2020, we have conducted a telephone survey that included 515 consecutive unselected patients with known thyroid disorders, of which 350 were affected by AITD. All 11 definitive diagnosis of COVID-19 (def-sympt-COVID-19) belonged to the AITD group, while the rest 14 cases highly suspected for COVID-19 (suspect-sympt-COVID-19) were equally detected in both group (7 in AITD and 7 in not-AITD). The overall prevalence of symptomatic COVID-19 (def-sympt-COVID-19 + suspect-sympt-COVID-19), recorded in the 350 AITD population was statistically significant higher compared to that reported in the Italian and Tuscan general population at the same time period of the present survey (18/350 = 5.14% vs 516/100000 = 0.51% [p < 0.001; OR = 10.45, 95% CI 6.45–16.92] and vs 394/100000 = 0.39% [p < 0.001; OR = 13.70, 95% CI 8.44–22.25], respectively).

Therefore, our results suggest a higher prevalence of SARS-CoV-2 infection and COVID-19 disease in patients with AITD.

Post-acute COVID-19 syndrome and its prolonged effects: An updated systematic review

Objective

This systematic review aimed at estimating the prevalence of post-acute COVID-19 symptoms in view of published literature that studied prolonged clinical manifestations after recovery from acute COVID-19 infection.

Methods

Relevant databases were searched for extraction of articles. For data synthesis, based on the distribution of quantitative variables, they were expressed as mean ± standard deviation (SD) or median and interquartile range (IQR). Qualitative variables were presented as frequency (n) and percentages (%).

Results

Twenty-one articles qualified for the final analysis. The most common persistent clinical manifestations were fatigue (54.11%), dyspnea (24.38%), alopecia (23.21%), hyperhidrosis (23.6%), insomnia (25.98%), anxiety (17.29%), and arthralgia (16.35%). In addition to these symptoms, new-onset hypertension, diabetes, neuropsychiatric disorders, and bladder incontinence were also reported.

Conclusion

Clinical features of post-acute COVID-19 infection can manifest even after 60 days of initial infection. Multidisciplinary care along with regular follow-up must be provided to such patients.

•

Clinical features of post-acute COVID-19 infection can manifest even after 60 days of initial infection.

•

Prolonged symptoms and signs are being reported in observational studies and case reports every day. Although such symptoms are usually experienced in survivors of critical illness, the post-acute effects of COVID-19 are equally being reported in patients with mild severity of disease who do not require hospitalization.

•

Necessary future research includes stratification of these post-acute effects with gender, age, and comorbid conditions in acute, subacute, and chronic phases of the disease.

Effect of COVID-19 on lipid profile parameters and its correlation with acute phase reactants: A single-center retrospective analysis

Background and objective

The development and correlation of dyslipidemia is unknown in COVID-19. This investigation was performed to assess the pathological alterations in lipid profile and their association in COVID-19.

Methods

This was a retrospective study performed on real-world patients to assess serum levels of LDL-C, HDL, TG, TC on COVID-19 patients (mild: 319; moderate: 391; critical: 357). Age- and gender-matched controls who had their lipid profiles in the same period were included as the control group.

Results

LDL-C, HDL, TG, and TC levels were significantly lower in COVID-19 patients when compared with the control group (P < 0.001, 0.047, 0.045, <0.001, respectively). All parameters decreased gradually with COVID-19 disease severity (LDL-C: median (IQR), mild: 98 (91,134); moderate: 97 (81,113); critical: 68 (68,83); HDL: mild: 45 (37,50); moderate: 46 (41,50); critical: 40 (37,46); TG: mild: 186 (150,245); moderate: 156 (109,198); critical: 111 (98,154); TC: mild: 224 (212,238); moderate: 212 (203,213); critical: 154 (125,187)). Logistic regression demonstrated lipid profile as predictor of severity of COVID-19 disease.

Conclusion

Hypolipidemia develops in increasing frequency with severe COVID-19 disease. It inversely correlates with levels of acute-phase reactants, indicating SARS-COV-2 as the causative agent for alteration in lipid and thyroid levels.

Immunopathological changes, complications, sequelae and immunological memory in COVID-19 patients

Confirmed SARS-CoV-2-caused disease (COVID-19) cases have reached 275.65 million worldwide. Although the majority of COVID-19 patients present mild to moderate symptoms, some have severe complications including death. We first reviewed the pathogenesis on ACE2, a binding receptor of SARS-CoV-2 expressed in multiple organs, and prevalent multinucleate syncytia in the lung tissues of COVID-19 patients. Then, we evaluated the pathological, immunological changes and sequelae in the major organs. Finally, we reviewed the immunological memory after SARS-CoV-2 infection and vaccination. The binding of SARS-Cov-2 to ACE2 receptor results in reduced ACE2 protein levels, which may lead to elevated susceptibility to inflammation, cell death, organ failure, and potentially severe illness. These damages increase the risk of health problems over a long period, which result in many complications. The complications in multiple organs lead to the increased risk of long-term health problems that require additional attention. A multidisciplinary care team is necessary for further management and recovery of the COVID-19 survivors. Many COVID-19 patients will probably make antibodies against SARS-CoV-2 virus for most of their lives, and the immunity against reinfection would last for 3-61 months.

Diabetes as a potential compounding factor in COVID-19-mediated male subfertility

Recent work indicates that male fertility is compromised by SARS-CoV-2 infection. Direct effects derive from the presence of viral entry receptors (ACE2 and/or CD147) on the surface of testicular cells, such as spermatocytes, Sertoli cells, and Leydig cells. Indirect effects on testis and concentrations of male reproductive hormones derive from (1) virus-stimulated inflammation; (2) viral-induced diabetes, and (3) an interaction between diabetes and inflammation that exacerbates the deleterious effect of each perturbation. Reproductive hormones affected include testosterone, luteinizing hormone, and follicle-stimulating hormone. Reduction of male fertility is also observed with other viral infections, but the global pandemic of COVID-19 makes demographic and public health implications of reduced male fertility of major concern, especially if it occurs in the absence of serious symptoms that would otherwise encourage vaccination. Clinical documentation of COVID-19-associated male subfertility is now warranted to obtain quantitative relationships between infection severity and subfertility; mechanistic studies using animal models may reveal ways to mitigate the problem. In the meantime, the possibility of subfertility due to COVID-19 should enter considerations of vaccine hesitancy by reproductive-age males.

Menstrual abnormalities after COVID-19 vaccines: A systematic review

The objective of this systematic review is to give a comprehensive interpretation of menstrual cycle changes after the COVID-19 vaccination. Additionally, it is imperative to assess reports of menstrual changes following vaccination to dispel concerns that COVID-19 vaccines hinder the likelihood of pregnancy in the long run. A literature review was conducted using digital databases to systematically identify the studies reporting any menstrual abnormalities after the COVID-19 vaccine. Detailed patient-level study characteristics including the type of study, sample size, administered vaccines, and menstrual abnormalities were abstracted. A total of 78 138 vaccinated females were included in this review from 14 studies. Of these, 39 759 (52.05%) had some form of a menstrual problem after vaccination. Due to the lack of published research articles, preprints were also included in this review. Menorrhagia, metrorrhagia, and polymenorrhea were the most commonly observed problems and the overall study-level rate of menstrual abnormality ranged from 0.83% to 90.9%. Age, history of pregnancy, systemic side-effects of COVID-19, smoking, and second dose of COVID-19 vaccine were predictors of menstrual problems after vaccination.

Association of ABO blood group with COVID-19 severity, acute phase reactants and mortality

INTRODUCTION

Coronavirus disease 2019 (COVID-19) is the ongoing pandemic with multitude of manifestations and association of ABO blood group in South-East Asian population needs to be explored.

METHODS

It was a retrospective study of patients with COVID-19. Blood group A, B, O, and AB were identified in every participant, irrespective of their RH type and allotted groups 1, 2,3, and 4, respectively. Correlation between blood group and lab parameters was presented as histogram distributed among the four groups. Multivariate regression and logistic regression were used for inferential statistics.

RESULTS

The cohort included 1067 patients: 521 (48.8%) participants had blood group O as the prevalent blood type. Overall, 10.6% COVID-19-related mortality was observed at our center. Mortality was 13.9% in blood group A, 9.5% in group B, 10% in group C, and 10.2% in AB blood group (p = 0.412). IL-6 was elevated in blood group A (median [IQR]: 23.6 [17.5,43.8]), Procalcitonin in blood group B (median [IQR]: 0.54 [0.3,0.7]), D-dimers and CRP in group AB (median [IQR]: 21.5 [9,34]; 24 [9,49], respectively). Regarding severity of COVID-19 disease, no statistical difference was seen between the blood groups. Alteration of the acute phase reactants was not positively associated with any specific blood type.

CONCLUSION

In conclusion, this investigation did not show significant association of blood groups with severity and of COVID-19 disease and COVID-19-associated mortality.

Low FT3 is an independent marker of disease severity in patients hospitalized for COVID-19

AIM

To study the prevalence of thyroid dysfunction and its association with disease severity in hospitalized patients of coronavirus disease-19 (COVID-19).

METHODS

In this retrospective cohort study, thyroid function tests (TFT) of 236 hospitalized patients of COVID-19 along with demographic, comorbid, clinical, biochemical and disease severity records were analysed. Patients were divided into previous euthyroid or hypothyroid status to observe the effect of prior hypothyroidism on the severity of COVID-19.

RESULTS

TFT abnormalities were common. Low free T3 (FT3), high thyroid-stimulating hormone (TSH) and low TSH were seen in 56 (23.7%), 15 (6.4%) and 9 (3.8%) patients, respectively. The median levels of TSH (2.06 vs 1.26 mIU/mL, P = 0.001) and FT3 (2.94 vs 2.47 pg/mL, P < 0.001) were significantly lower in severe disease. Previous hypothyroid status (n = 43) was associated with older age, higher frequency of comorbidities, higher FT4 and lower FT3. TFT did not correlate with markers of inflammation (except lactate dehydrogenase); however, FT3 and TSH negatively correlated with outcome severity score and duration of hospital stay. Cox regression analysis showed that low FT3 was associated with severe COVID-19 (P = 0.032, HR 0.302; CI 0.101-0.904), irrespective of prior hypothyroidism.

CONCLUSIONS

Functional thyroid abnormalities (low FT3 and low TSH) are frequently seen in hospitalized patients of COVID-19. Although these abnormalities did not correlate with markers of inflammation, this study shows that low FT3 at admission independently predicts the severity of COVID-19.

Association of hypothyroidism with acute COVID-19: a systematic review

OBJECTIVE

There is an increasing body of literature on the impact of COVID-19 on the pituitary-thyroid axis. Therefore, we conducted a systematic review to assess the prevalence of hypothyroidism in patients with COVID-19.

METHODS

A literature review was conducted using LitCOVID for study selection in PubMed and MEDLINE till May 2021. All relevant original articles evaluating thyroid dysfunction were included and information regarding the prevalence of hypothyroid disease in COVID-19 was retrieved from the eligible articles.

RESULTS

Out of 32 articles, six articles qualified for the final analysis which included 1160 patients. There was significant heterogeneity among the included articles. Most of the patients had lower mean triiodothyronine (T3) and normal or low thyroid-stimulating hormone (TSH). Increased TSH ranged from 5.1% to 8% while low T3 was present in up to 28% of the patients. In these studies, the prevalence of altered thyroid hormones was significantly more in COVID-19 patients as compared to control groups. A positive correlation between low mean T3 and clinical severity of COVID-19 was reported.

CONCLUSION

This systematic review reveals a significant proportion of hypothyroidism associated with COVID-19. Therefore, routine assessment of thyroid function is warranted in hospitalized COVID-19 patients.

Case series: Rare cases of thyroid storm in COVID-19 patients

Thyroid storm is an uncommon life-threatening thyroid dysfunction which was observed for the first time among patients infected with Coronavirus 2019 (COVID-19). The diagnosis and treatment of the rare thyroid distinctions such as thyroid storm in COVID-19-infected patients should be critically considered alongside common treatments of COVID-19 infection.

Physiological Role and Use of Thyroid Hormone Metabolites - Potential Utility in COVID-19 Patients

Thyroxine and triiodothyronine (T3) are classical thyroid hormones and with relatively well-understood actions. In contrast, the physiological role of thyroid hormone metabolites, also circulating in the blood, is less well characterized. These molecules, namely, reverse triiodothyronine, 3,5-diiodothyronine, 3-iodothyronamine, tetraiodoacetic acid and triiodoacetic acid, mediate both agonistic (thyromimetic) and antagonistic actions additional to the effects of the classical thyroid hormones. Here, we provide an overview of the main factors influencing thyroid hormone action, and then go on to describe the main effects of the metabolites and their potential use in medicine. One section addresses thyroid hormone levels in corona virus disease 19 (COVID-19). It appears that i) the more potently-acting molecules T3 and triiodoacetic acid have shorter half-lives than the less potent antagonists 3-iodothyronamine and tetraiodoacetic acid; ii) reverse T3 and 3,5-diiodothyronine may serve as indicators for metabolic dysregulation and disease, and iii) Nanotetrac may be a promising candidate for treating cancer, and resmetirom and VK2809 for steatohepatitis. Further, the use of L-T3 in the treatment of severely ill COVID-19 patients is critically discussed.

The Association of Thyroid Hormone Changes with Inflammatory Status and Prognosis in COVID-19

BACKGROUND

COVID-19 infection may have multiorgan effects in addition to effects on the lungs and immune system. Recently, studies have found thyroid function abnormalities in COVID-19 cases which were interpreted as euthyroid sick syndrome (ESS) or destructive thyroiditis. Therefore, in this study, we aimed to evaluate the thyroid function status and thyroid autoimmunity in COVID-19 patients. Material and Method. 205 patients were included. The medical history and laboratory parameters at admission were collected from medical records. Serum thyroid-stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), thyroid peroxidase antibody, and thyroglobulin antibody were measured, and patients were classified according to thyroid function status.

RESULTS

34.1% of the patients were euthyroid. Length of hospitalization (p < 0.001), rate of oxygen demand (p < 0.001), and intensive care unit (ICU) admission (p=0.022) were lower, and none of the euthyroid patients died. 108 (52.6%) patients were classified to have ESS, 57 were classified as mild, and 51 were moderate. The inflammatory parameters were higher in patients with moderate ESS. In cluster analysis, a high-risk group with a lower median FT3 value (median = 2.34 ng/L; IQR = 0.86), a higher median FT4 value (median = 1.04 ng/dL; IQR = 0.33), and a lower median TSH value (median = 0.62 mIU/L; IQR = 0.59) included 8 of 9 died patients and 25 of the 31 patients that were admitted to ICU. Discussion. Length of hospitalization, oxygen demand, ICU admission, and mortality were lower in euthyroid patients. Moreover, none of the euthyroid patients died. In conclusion, evaluation of thyroid function tests during COVID-19 infection may give information about the prognosis of disease.