Cited by 316Thyroid Disorders and TreatmentsClinical Nutrition and GastroenterologyAdrenal Hormones and Disorders

Non-Thyroidal Illness in the ICU: A Syndrome with Different Faces

Open access
Van den Berghe, Greet·2014·Thyroid®

Abstract

Background: Critically ill patients typically present with low or low-normal plasma thyroxine, low plasma triiodothyronine (T3), increased plasma reverse T3 (rT3) concentrations, in the absence of a rise in thyrotropin (TSH). This constellation is referred to as nonthyroidal illness syndrome (NTI). Although it is long known that the severity of NTI is associated with risk of poor outcomes of critical illness, the causality in this association has not been well investigated. Summary: In this narrative review, the different faces of NTI during critical illness are highlighted. Acute alterations are dominated by changes in thyroid hormone binding, peripheral thyroid hormone uptake, and alterations in the expression and activity of the type-1 and type-3 deiodinases. It was recently shown that at least part of these acute changes are brought about by concomitant macronutrient restriction, and this part appears adaptive and beneficial. However, the face of the NTI in the prolonged phase of critical illness is different, when patients are fully fed but continue to depend on intensive medical care. In that prolonged phase of illness, hypothalamic thyrotropin releasing hormone (TRH) expression is suppressed and explains reduced TSH secretion and whereby reduced thyroidal hormone release. During prolonged critical illness, and in the presence of adequate nutrition, several tissue responses could be interpreted as compensatory to low thyroid hormone availability, such as increased expression of monocarboxylate transporters, upregulation of type-2 deiodinase activity, and increased sensitivity at the receptor level. Infusing hypothalamic releasing factors in these prolonged critically ill patients can reactivate the thyroid axis and induce an anabolic response. Conclusions: It is clear that the name “NTI” during critical illness refers to a syndrome with different faces. Tolerating the early “fasting response” to critical illness and its concomitant changes in thyroid hormone parameters appears to be wise and beneficial. This thus applies to the NTI present in the majority of the patients treated in intensive care units. However, the NTI that occurs in prolonged critically ill patients appears different with regard to both its causes and consequences. Future studies should specifically target this selected population of prolonged critically ill patients, and, after excluding iatrogic drug interferences, investigate the effect on outcome of treatment with hypothalamic releasing factors in adequately powered randomized controlled trials.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1089/thy.2014.0201

Cites

66 of 66 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • These responses include increased tissue expression of monocarboxylate transporters, upregulation of type-2 deiodinase activity, and increased sensitivity at the receptor level.

    “These responses include increased tissue expression of monocarboxylate transporters, upregulation of type-2 deiodinase activity, and increased sensitivity at the receptor level [87].”

    From An update on non-thyroidal illness syndrome (2021) · cites this paper as [87]

  • Many experimental and clinical studies point to a biphasic neuroendocrine pattern in critical illness.

    “Many experimental and clinical studies pointed to a biphasic neuroendocrine pattern in critical illness as conceptualized by dr Van den Berghe and colleagues (see reviews [87, 94]).”

    From An update on non-thyroidal illness syndrome (2021) · cites this paper as [87]

  • During prolonged critical illness, several tissue responses reported from both animal and human studies could be interpreted as compensatory to low thyroid hormone availability.

    “During prolonged critical illness, several tissue responses reported from both animal and human studies could be interpreted as compensatory to low thyroid hormone availability.”

    From An update on non-thyroidal illness syndrome (2021) · cites this paper as [87]

  • In NTI syndrome and other constellations of thyroid allostasis, TSH measurement fails as a diagnostic test because the TSH set point is non-fixed.

    “In extremis, the notion of a non-fixed TSH set point is typified in the NTI syndrome and other constellations of thyroid allostasis where TSH measurement fails as a diagnostic test for that reason (117).”

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

2 of the 68 references couldn’t be matched to a known paper.

Cited by

Sorted by citations

Authors
Van den Berghe, G.
Affiliations
Clinical Division and Laboratory of Intensive Care Medicine
Venue
Thyroid®
Published
2014-10
Volume
24
Issue
10
Pages
1456-1465
ISSN
  • 1050-7256 (ISSN-L)
  • 1557-9077
OpenAlex
W2110625788
Cited by
316
References
68
Citations by year
2026: 24 · 2025: 25 · 2024: 25 · 2023: 41 · 2022: 34 · 2021: 47 · 2020: 26 · 2019: 19 · 2018: 24 · 2017: 16 · 2016: 21 · 2015: 10 · 2014: 3
FWCI
2.65
Type
journal article
Language
en
Open access
Locations
  • Thyroid (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Lirias (KU Leuven) (submittedVersion)
Funders
Vlaamse regering
Topics
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Thyroid Disorders and Treatments
  • Health Sciences › Nursing › Nutrition and Dietetics › Clinical Nutrition and Gastroenterology
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Adrenal Hormones and Disorders
Keywords
low T3 syndrome, critical illness, thyroid hormone binding, reverse T3, deiodinases, type 2 deiodinase, thyroid hormone uptake, thyroid-stimulating hormone, thyrotropin-releasing hormone, hypothalamic-pituitary-thyroid axis, monocarboxylate transporters, prolonged critical illness, intensive care unit patients
MeSH terms
Euthyroid Sick Syndromes, Humans, Intensive Care Units, Nutritional Status, Prognosis, Risk Factors, Severity of Illness Index, Stress, Physiological, Thyroid Gland, Thyroid Hormones, Time Factors, Biomarkers, Critical Illness

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review