Nonthyroidal illness syndrome in enterocutaneous fistulas

Total triiodothyronine level associated with disease severity for patients with emergent status

Thyroid hormones are metabolic indicators to evaluate the physical condition of emergency hospitalized patients, while the relationship between total triiodothyronine and the severity of emergency inpatients is still unclear. To explore the thyroid function levels of inpatients in emergency ward and the status of combined Nonthyroidal illness syndrome (NTIS), and to emphasize the importance of thyroid hormone examination for non-endocrinology inpatients. According to thyroid function of inpatients in emergency ward, they were divided into NTIS group and non-NTIS group, the hematological characteristics and TH levels of each group were analyzed. Based on clinical diagnoses, the hospitalized patients were divided into three major groups, namely infection group, non-infection group and impaired organ function group. Among them, infection group was further divided into sepsis group, lung infection group and local infection group, altogether five groups. The thyroid function levels and low values in each group were evaluated, and the correlation between hormone levels and inflammatory factors, nutritional indicators and the relationship with the risk of death was discussed. The inpatient rate in emergency ward complicated with NTIS was 62.29%, T3 was the most sensitive index of NTIS, followed by FT3. Compared to non-NTIS group, the NTIS group had an increased risk of death. The sepsis group and impaired organ function group had the highest rates of complicated NTIS, reaching 83.33% and 78.12% respectively. Spearman's correlation analysis implied T3/T4/FT3 levels were positively correlated with ALb and PLT (except T4), and negatively correlated with CRP, D-Dimer, IL-6 and Fer. The Receiver Operating Curve (ROC) and Area under the curve (AUC) showed T3 levels alone were strongly associated with the risk of death (AUC 0.750; 95% CI 0.673-0.828; P < 0.001). T3 is the most sensitive indicator for emergency patients, followed by FT3. The decrease of T3 level has a good predictive value for mortality risk. Thyroid function should be monitored in critically ill patients.

Thyroid allostasis in drug-free affective disorder patients

AIM

To assess the thyroid allostasis in drug-free patients with affective disorder.

METHODS

Patients with major depressive disorder or bipolar disorder as drug-free, defined as those without psychiatric drugs exposure for at least 4 months before admission, from a tertiary hospital were recruited in this cross-sectional study. The primary outcomes were "structure parameters of thyroid homeostasis", which include "thyroid's secretory capacity" (SPINA-GT), "sum step-up activity of deiodinases" (SPINA-GD), the ratio of total to free thyroxine and "thyroid homeostasis central set point" (TSH index and "thyroid feedback quantile-based index" [TFQI]), calculated by TSH and thyroid hormones measured at admission. A healthy population and non-affective psychiatric disorder (schizophrenia) from the same catchment area were recruited as two comparison groups.

RESULTS

A total of 1263 cases of major depressive disorder, 1619 cases of bipolar disorder, 1186 cases of schizophrenia, and 162 healthy controls were included in the study. Compared to healthy control, GD and ratio of total to free thyroxine were lower in affective disorders. Bipolar with mania episode had higher GT than bipolar with depressive episode and major depressive disorder (median level at 3.70 vs. 3.04 and 3.03, respectively). Compared with healthy control, schizophrenia had higher TSH index and TFQI, but no increase in these parameters in major depressive disorder and bipolar disorder.

CONCLUSION

Affective disorders have a unique profile of thyroid allostasis with impaired step-up deiodinase activity and reduced serum protein binding of thyroid hormones, but no change in thyroid homeostasis central set point. Mania episode may be associated with higher thyroid secretory capacity.

Decreased triiodothyronine (T3) as a predictor for prolonged mechanical ventilation in critically ill patients with cardiac surgery

BACKGROUND

This study aimed to examine the correlation between thyroid hormone and prolonged mechanical ventilation (MV) in adult critically ill patients having undergone cardiac surgery.

METHODS

The present study refers to a retrospective, cohort study conducted at Nanjing First Hospital from March 2019 to December 2020. Patients receiving cardiac surgery and admitting to the Cardiovascular Intensive Care Unit (CVICU) in the study period were screened for potential inclusion. Demographic information, thyroid hormone and other laboratory measurements and outcome variables were recorded for analysis. Prolonged MV was defined as the duration of MV after cardiac surgery longer than 5 days. Thyroid hormones were assessed for the prognostic significance for prolonged MV.

RESULTS

One thousand eight hundred ninety-six patients who underwent cardiac surgery were screened for potential enrollment. Overall, 118 patients were included and analyzed in this study. Patients fell to the control (n = 64) and the prolonged MV group (n = 54) by complying with the duration of MV after cardiac surgery. The median value of total triiodothyronine (TT3) and free triiodothyronine (FT3) were 1.03 nmol/L and 3.52 pmol/L in the prolonged MV group before cardiac surgery, significantly lower than 1.23 nmol/L (P = 0.005) and 3.87 pmol/L, respectively in control (P = 0.038). Multivariate logistic regression analysis indicated that TT3 before surgery (pre-op TT3) had an excellent prognostic significance for prolonged MV (OR: 0.049, P = 0.012).

CONCLUSIONS

This study concluded that decreased triiodothyronine (T3) could be common in cardiac patients with prolonged MV, and it would be further reduced after patients undergo cardiac surgery. Besides, decreased T3 before surgery could act as an effective predictor for prolonged MV after cardiac surgery.

Nonthyroidal illness syndrome in acute pancreatitis patients: an 8-year cohort study

BACKGROUND

Nonthyroidal illness syndrome (NTIS) is common in critical illness and is associated with poor prognosis. The aim of this study was to find the prevalence, charateristics, and prognosis of NTIS and its correlation with outcomes in AP patients.

METHODS

A retrospective review of AP patients with a diagnosis of NTIS from Jan 2012 to September 2020 was performed. The serum thyroidal hormone (TH) disturbances, as well as the demographic characteristics and clinical outcomes of the study patients, were collected and analyzed.

RESULTS

Over the eight years, 183 included AP patients were diagnosed as NTIS, constituting an incidence of 64.7%. Patients with NTIS were admitted with worse condition based on the higher APACHE II score, SOFA score, Balthazar's CT score, CRP and lower albumin than euthyroid patients. Also, these patients had a longer ICU duration (3, 2-10 vs 2, 0-3, days, P = 0.039) and tended to be more likely to develop infected pancreatic necrosis (IPN) (15.3% vs 6.3%, P = 0.087) and gastrointestinal fistula (6% vs 0%, P = 0.082) than euthyroid patients. Free triiodothyronine (FT3) was found the best performance in predicting death compared by other well-recognized biomarkers.

CONCLUSION

NTIS is common in AP patients within 7 days after the onset of the disease. NTIS is associated with the worse characteristics at admission and poor outcome during the course. FT3 should be investigate as a potential biomarker in the prediction of death in AP patients.

Nonthyroidal Illness Syndrome in Patients With Short-Bowel Syndrome

BACKGROUND

Nonthyroidal illness syndrome (NTIS) is prevalent in critical illness and is associated with poor outcomes. However, only few studies have focused on the relationship between NTIS and short-bowel syndrome (SBS). The aim of this study was to investigate the prevalence, etiology, and prognosis of NTIS and its correlation with clinical variables in adult patients with SBS.

METHODS

Sixty-one eligible adults diagnosed with SBS, from December 2016 to December 2018, were retrospectively identified from a prospectively maintained database. Demographic and clinical characteristics (including thyroid hormones and nutrition variables) were evaluated for each participant.

RESULTS

The prevalence of NTIS in adults with SBS was 52.5%. Patients with NTIS tended to have a longer duration of hospital stay and poor survival, but the results were not significant. A decreased, standard thyroid-stimulating hormone index and sum activity of deiodinases and an increased secretory capacity by the thyroid were observed in the NTIS group. Receiver operating characteristic curve analysis showed that insulin-like growth factor-1 (IGF-1) had better performance for distinguishing NTIS from patients with euthyroidism, with an area under the curve of 0.862 (cutoff, 101.0; sensitivity, 0.813; and specificity, 0.800).

CONCLUSIONS

NTIS is a common complication in adult patients with SBS. Patients with NTIS tend to have a worse nutrition status and poor prognosis. A potential pituitary thyrotroph dysfunction and hypodeiodination condition may play a role in the pathophysiology of NTIS in SBS. Furthermore, IGF-1 is a meaningful predictor for distinguishing NTIS from euthyroid.

Higher Prevalence of "Low T3 Syndrome" in Patients With Chronic Fatigue Syndrome: A Case-Control Study

Chronic fatigue syndrome (CFS) is a heterogeneous disease with unknown cause(s). CFS symptoms resemble a hypothyroid state, possibly secondary to chronic (low-grade) (metabolic) inflammation. We studied 98 CFS patients (21-69 years, 21 males) and 99 age- and sex-matched controls (19-65 years, 23 males). We measured parameters of thyroid function, (metabolic) inflammation, gut wall integrity and nutrients influencing thyroid function and/or inflammation. Most remarkably, CFS patients exhibited similar thyrotropin, but lower free triiodothyronine (FT3) (difference of medians 0.1%), total thyroxine (TT4) (11.9%), total triiodothyronine (TT3) (12.5%), %TT3 (4.7%), sum activity of deiodinases (14.4%), secretory capacity of the thyroid gland (14.9%), 24-h urinary iodine (27.6%), and higher % reverse T3 (rT3) (13.3%). FT3 below the reference range, consistent with the "low T3 syndrome," was found in 16/98 CFS patients vs. 7/99 controls (OR 2.56; 95% confidence interval = 1.00-6.54). Most observations persisted in two sensitivity analyses with more stringent cutoff values for body mass index, high-sensitive C-reactive protein (hsCRP), and WBC. We found possible evidence of (chronic) low-grade metabolic inflammation (ferritin and HDL-C). FT3, TT3, TT4, and rT3 correlated positively with hsCRP in CFS patients and all subjects. TT3 and TT4 were positively related to hsCRP in controls. Low circulating T3 and the apparent shift from T3 to rT3 may reflect more severely depressed tissue T3 levels. The present findings might be in line with recent metabolomic studies pointing at a hypometabolic state. They resemble a mild form of "non-thyroidal illness syndrome" and "low T3 syndrome" experienced by a subgroup of hypothyroid patients receiving T4 monotherapy. Our study needs confirmation and extension by others. If confirmed, trials with, e.g., T3 and iodide supplements might be indicated.

Thyroid Allostasis-Adaptive Responses of Thyrotropic Feedback Control to Conditions of Strain, Stress, and Developmental Programming

The hypothalamus-pituitary-thyroid feedback control is a dynamic, adaptive system. In situations of illness and deprivation of energy representing type 1 allostasis, the stress response operates to alter both its set point and peripheral transfer parameters. In contrast, type 2 allostatic load, typically effective in psychosocial stress, pregnancy, metabolic syndrome, and adaptation to cold, produces a nearly opposite phenotype of predictive plasticity. The non-thyroidal illness syndrome (NTIS) or thyroid allostasis in critical illness, tumors, uremia, and starvation (TACITUS), commonly observed in hospitalized patients, displays a historically well-studied pattern of allostatic thyroid response. This is characterized by decreased total and free thyroid hormone concentrations and varying levels of thyroid-stimulating hormone (TSH) ranging from decreased (in severe cases) to normal or even elevated (mainly in the recovery phase) TSH concentrations. An acute versus chronic stage (wasting syndrome) of TACITUS can be discerned. The two types differ in molecular mechanisms and prognosis. The acute adaptation of thyroid hormone metabolism to critical illness may prove beneficial to the organism, whereas the far more complex molecular alterations associated with chronic illness frequently lead to allostatic overload. The latter is associated with poor outcome, independently of the underlying disease. Adaptive responses of thyroid homeostasis extend to alterations in thyroid hormone concentrations during fetal life, periods of weight gain or loss, thermoregulation, physical exercise, and psychiatric diseases. The various forms of thyroid allostasis pose serious problems in differential diagnosis of thyroid disease. This review article provides an overview of physiological mechanisms as well as major diagnostic and therapeutic implications of thyroid allostasis under a variety of developmental and straining conditions.

Distinct Features of Nonthyroidal Illness in Critically Ill Patients With Infectious Diseases

Nonthyroidal illness (NTI), often observed in critically ill patients, arises through diverse alterations in the hypothalamus-pituitary-thyroid (HPT) axis. However, the causal relationship between underlying disease and NTI diversity in critically ill patients is poorly understood.The aim of this study was to examine NTI severity and adverse outcomes in critically ill patients with respect to their underlying disease(s).The medical records of 616 patients admitted to the intensive care unit (ICU) between January 2009 and October 2014 were retrospectively reviewed. Patients with known diseases or taking medications that affect thyroid function were excluded. All-cause mortality (ACM) and length of stay (LOS) in the ICU were assessed as adverse outcomes.The enrolled patients (n = 213) were divided into the following 4 groups according to the severity of NTI at the nadir of their thyroid function test (TFT): normal (n = 11, 5.2%), mild NTI (n = 113, 53.1%), moderate NTI (n = 78, 36.6%), and severe NTI (n = 11, 5.2%). There was no significant difference between the groups in terms of age and gender. NTI severity showed a significantly strong association with ACM (P < 0.0001) and a significant positive association with LOS in the ICU (P = 0.031). After adjusting for age, gender, and current medications affecting TFT, increasing NTI severity led to increased ACM (odds ratio = 3.101; 95% confidence interval = 1.711-5.618; P < 0.0001). Notably, the prevalence of moderate-to-severe NTI was markedly higher in patients with infectious disease than in those with noninfectious disease (P = 0.012). Consistent with this, serum C-reactive protein levels were higher in patients with moderate-to-severe NTI (P = 0.016).NTI severity is associated with increased ACM, LOS, and underlying infectious disease. Future studies will focus on the biological and clinical implications of infectious disease on the HPT axis.

Euthyroid Sick Syndrome

In this review, we discuss the characteristics, pathophysiology, and therapeutic implications of the euthyroid sick syndrome. Multiple mechanisms have been identified to contribute to the development of euthyroid sick syndrome, including alterations in the iodothyronine deiodinases, thyroid-stimulating hormone secretion, thyroid hormone binding to plasma protein, transport of thyroid hormone in peripheral tissues, and thyroid hormone receptor activity. The euthyroid sick syndrome appears to be a complex mix of physiologic adaptation and pathologic response to acute illness. The underlying cause for these alterations has not yet been elucidated. Treatment of the euthyroid sick syndrome with thyroid hormone to restore normal serum thyroid hormone levels in an effort to improve disease prognosis and outcomes continues to be a focus of many clinical studies, although currently available data do not provide evidence of a clear benefit of treatment.

Calculated Parameters of Thyroid Homeostasis: Emerging Tools for Differential Diagnosis and Clinical Research

Although technical problems of thyroid testing have largely been resolved by modern assay technology, biological variation remains a challenge. This applies to subclinical thyroid disease, non-thyroidal illness syndrome, and those 10% of hypothyroid patients, who report impaired quality of life, despite normal thyrotropin (TSH) concentrations under levothyroxine (L-T4) replacement. Among multiple explanations for this condition, inadequate treatment dosage and monotherapy with L-T4 in subjects with impaired deiodination have received major attention. Translation to clinical practice is difficult, however, since univariate reference ranges for TSH and thyroid hormones fail to deliver robust decision algorithms for therapeutic interventions in patients with more subtle thyroid dysfunctions. Advances in mathematical and simulative modeling of pituitary-thyroid feedback control have improved our understanding of physiological mechanisms governing the homeostatic behavior. From multiple cybernetic models developed since 1956, four examples have also been translated to applications in medical decision-making and clinical trials. Structure parameters representing fundamental properties of the processing structure include the calculated secretory capacity of the thyroid gland (SPINA-GT), sum activity of peripheral deiodinases (SPINA-GD) and Jostel's TSH index for assessment of thyrotropic pituitary function, supplemented by a recently published algorithm for reconstructing the personal set point of thyroid homeostasis. In addition, a family of integrated models (University of California-Los Angeles platform) provides advanced methods for bioequivalence studies. This perspective article delivers an overview of current clinical research on the basis of mathematical thyroid models. In addition to a summary of large clinical trials, it provides previously unpublished results of validation studies based on simulation and clinical samples.

Role of enteral nutrition in nonthyroidal illness syndrome: a retrospective observational study

BACKGROUND

The nonthyroidal illness syndrome (NTIS) is prevalent among patients with enterocutaneous fistula and is associated with poor outcomes. The present study aimed to explore the role of enteral nutrition (EN) therapy on thyroid function among patients with enterocutaneous fistula and NTIS.

METHODS

We conducted a retrospective observational study among patients with enterocutaneous fistula between January 2013 and April 2014. All enrolled patients received EN therapy. Thyroid function and other parameters were measured.

RESULTS

After administration of 4 weeks of EN therapy, NTIS was resolved in 66 patients (Group A), while it persisted in 14 patients (Group B). The overall treatment success rate was 82.50 %. There were no significant differences between groups A and B at baseline for all parameters, except for the time from admission to start of EN therapy. The logistic analysis revealed that the time from admission to start of EN therapy was a significant independent indicator for achieving resolution of NTIS in our cohort.

CONCLUSIONS

This retrospective observational cohort study demonstrated that EN therapy can aid in the resolution of NTIS among patients with enterocutaneous fistula. These findings confirm the benefit of EN in the treatment of enterocutaneous fistula.

Dynamics of albumin synthetic response to intra-abdominal abscess in patients with gastrointestinal fistula

BACKGROUND

Low serum albumin concentration is a predictor of failure of source control for intra-abdominal infection. However, data on dynamics of albumin synthesis in these patients and to what extent these changes contribute to hypoalbuminemia are relatively scarce. We investigated in a group of patients with gastrointestinal fistula the dynamic response of liver albumin synthesis to intra-abdominal abscess and how these related to hypoalbuminemia and circulating endocrine hormone profiles.

METHODS

Eight gastrointestinal fistula patients scheduled to undergo percutaneous abscess sump drainage were enrolled prospectively to measure albumin synthesis rates at different stages of the inflammatory response (immediately after diagnosis and 7 d following sump drainage when clinical signs of intra-abdominal sepsis had been eradicated). Eight age-, sex-, and body mass index-matched intestinal fistula patients were studied as control patients. Consecutive arterial blood samples were drawn during a primed-constant infusion (priming dose: 4 micromol·kg(-1), infusion rate: 6 micromol·kg(-1)·min(-1)) to determine the incorporation rate of L-[ring-(2)H5]-phenylalanine directly into plasma albumin using gas chromatography/mass spectrometry analysis.

RESULTS

Patients suffering from intra-abdominal infection had reduced plasma albumin and total plasma protein concentrations, compared with control patients. Albumin fractional synthesis rates in patients with intra-abdominal abscess were decreased, compared with those in the control group. When the source of infection was removed, albumin synthesis rates returned to control values, whereas albumin concentrations did not differ significantly from the corresponding concentrations in control subjects and patients with intra-abdominal abscess.

CONCLUSION

Despite nutritional intervention, albumin synthesis rate is decreased in intestinal fistula patients with intra-abdominal abscess; albumin synthesis returns to control values during convalescence.