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Effects of N-acetylcysteine on Low T3 Syndrome

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ClinicalTrials.gov Identifier: NCT01501110
Recruitment Status : Completed
First Posted : December 29, 2011
Results First Posted : March 31, 2015
Last Update Posted : March 31, 2015
Information provided by (Responsible Party):

Study Description
Brief Summary:
The propose of this study is to determine whether N-acetylcysteine is effective in reversing the changes in thyroid hormones seen in critical illness, known as the low T3 syndrome.

Condition or disease Intervention/treatment Phase
Acute Myocardial Infarction Euthyroid Sick Syndrome Ischemic Heart Disease Drug: N-acetylcysteine Phase 4

Detailed Description:

The low T3 syndrome or nonthyroidal illness is characterized by low levels of T3, normal or high normal levels of rT3, low or normal levels of T4 and inappropriately normal or low levels of TSH. These changes affect up to 75% of patients and have prognostic implications.

Interleukin-6 (IL6) seems to have a causative role in the pathogenesis of nonthyroidal illness. There is evidence that the reduction in serum T3 was inversely associated with serum IL-6, while the rT3 have a positive association. The mechanism of action of cytokines on the metabolism of thyroid hormones has not been determined and the potential role of cytokines on the deiodases has been the focus of research.

In a cell culture model study, IL-6 was able to suppress the conversion of T4 to T3 by deiodases type 1 and 2 and stimulate the inactivation of T3 by deiodase type 3, a situation similar to nonthyroidal illness. The use of N-acetylcysteine prevented this alterations, been consistent with the hypothesis that IL6 inhibits the function of the deiodases by increasing the oxygen reactive species and by consuming gluthathione or some gluthathione dependent cofactor.

Considering the absence of human studies evaluating the use of N-acetylcysteine in nonthyroidal illness, the aim of this study is to investigate whether NAC has in vivo effect on changes of thyroid hormones.

Study Design

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 83 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Participant)
Primary Purpose: Treatment
Official Title: Evaluation of the Effects of N-acetylcysteine on Thyroid Hormone Levels in the Low T3 Syndrome
Study Start Date : November 2011
Primary Completion Date : July 2013
Study Completion Date : November 2013

Resource links provided by the National Library of Medicine

U.S. FDA Resources

Arms and Interventions

Arm Intervention/treatment
Active Comparator: n-acetylcysteine
intra-venous infusion of 1200 mg of n-acetylcysteine twice a day for 48 hours.
Drug: N-acetylcysteine
in infusion of 1200 mg of n-acetylcysteine twice a day for 48 hours
Other Names:
  • NAC
  • acetylcysteine
No Intervention: no intervention
No intervention

Outcome Measures

Primary Outcome Measures :
  1. Serum T3 Levels at 48 Hours [ Time Frame: 48 hours ]

Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 80 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • diagnosis of acute myocardial infarction with less than 12 hours of evolution
  • reperfusion therapy (primary angioplasty)

Exclusion Criteria:

  • Thyroid disease
  • Chronic renal disease with renal replacement therapy
  • hepatic insufficiency
  • immunosuppression
Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01501110

Hospital de Clínicas de Porto Alegre
Porto Alegre, Rio Grande do Sul, Brazil, 90540001
Instituto de Cardiologia
Porto Alegre, Rio Grande do Sul, Brazil, 90540001
Sponsors and Collaborators
Federal University of Rio Grande do Sul
Hospital de Clinicas de Porto Alegre
Programa de pós-graduação em endocrinologia
Principal Investigator: Josi Vidart Federal University of Rio Grande do Sul
Study Director: Ana maia Federal University of Rio Grande do Sul
More Information

Additional Information:
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Josi Vidart, Principal Investigator, Federal University of Rio Grande do Sul
ClinicalTrials.gov Identifier: NCT01501110     History of Changes
Other Study ID Numbers: 110061
First Posted: December 29, 2011    Key Record Dates
Results First Posted: March 31, 2015
Last Update Posted: March 31, 2015
Last Verified: March 2015

Keywords provided by Josi Vidart, Federal University of Rio Grande do Sul:
Euthyroid Sick Syndrome
low T3 syndrome
oxidative stress
ischemic heart disease

Additional relevant MeSH terms:
Heart Diseases
Myocardial Infarction
Myocardial Ischemia
Coronary Artery Disease
Euthyroid Sick Syndromes
Pathologic Processes
Cardiovascular Diseases
Vascular Diseases
Coronary Disease
Arterial Occlusive Diseases
Thyroid Diseases
Endocrine System Diseases
Antiviral Agents
Anti-Infective Agents
Respiratory System Agents
Free Radical Scavengers
Molecular Mechanisms of Pharmacological Action
Protective Agents
Physiological Effects of Drugs