Metabolism and Thyroid Hormone Changes During Exposure to Cold Temperatures

NCT00521729 | Completed

• 2 other identifiers: 07020207-DK-0202
• Study Type: interventional
• Target: 160
• Locations: 1 country
• Sites: 1

Brief Summary

This study will examine how body metabolism adjusts to small changes in environmental temperature and how it may be related to weight loss. Healthy, non-obese individuals between 18 and 60 years of age may be eligible for this study. The study consists of one screening visit and one 5-day admission to the NIH Clinical Center for the following procedures: Diet: Participants follow a proscribed diet consisting of 50% carbohydrates, 20% protein and 30% fat. DEXA scan to measure body fat. Subjects lie on a table above a source of X-rays while a very small dose of X-rays is passed through the body. Air displacement plethysmography (Bod-Pod) to study fat composition: Subjects sit in a small booth for 10 minutes wearing a swim suit and breathing normally through a tube. This test measures the person s weight and volume precisely. Metabolic room: Subjects stay 12 hours in a specialized room designed to measure the amount of oxygen breathed in and the amount of carbon dioxide breathed out. The room contains a private toilet and sink, treadmill, bed, desk, window, telephone and computer with television and internet access. While in this room, subjects undergo the following:

• Continuous heart rate monitor: Subjects wear an EKG monitor to analyze heart rate variability.
• Spontaneous movements: Subjects wear portable accelerometers at the hip and wrist to measure spontaneous physical movements.
• Continuous temperature monitor: Subjects swallow a small capsule that transmits internal body temperature via miniature, wireless sensors. Adhesive patches placed on the skin monitor external body temperature.
• Blood and urine collections: Subjects collect all of their urine during the 12 hours they are in the metabolic room. Blood samples are taken at specified intervals through a catheter that has been placed in a vein.
• Microdialysis: A small needle is placed into fat tissue just under the skin on the abdomen. A solution containing a minimal amount of ethanol is infused and samples of fluid are collected every 20 minutes as it leaves the fat pad. This helps determine the metabolism level. This procedure starts 30 minutes before entering the metabolic room and continues until the subject leaves the room. Fat tissue biopsy: A small piece of fat tissue is withdrawn through a needle from under the skin on the abdomen. The sample is used to study fat tissue size and ability to store sugar.

Conditions

Obesity

Keywords

Thyroid; Thermoregulation; Catecholamines; Energy Expenditure; Obesity; Healthy Volunteer; HV

Outcome Measures

Primary Outcomes (1)

• Changes in energy expenditure and in thyroid hormone levels

Secondary Outcomes (1)

• Changes in spontaneous physical activity and in thermic effect of food

Interventions

Exposure to Cold Temperature PROCEDURE

Eligibility Criteria

• Age: 18 Years - 60 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Age greater than or equal to18
• Written informed consent
• (for SDH study only: \<60 years old, documented SDH mutation without clinical evidence of pheochromocytoma or biochemical evidence of excess of catecholamines. The assessment will be performed within the context of the 00-CH-0093 protocol, P.I. Karel Pacak).

You may not qualify if:

• Hypo- or hyper-thyroid (history or TSH greater than 5.0 and less than 0.4 miU/L)
• Blood pressure greater than 140/90 mmHg or current antihypertensive therapy
• History of cardiovascular disease
• BMI less than or equal to 20 or greater than or equal to 35 Kg/m(2)
• Diabetes mellitus (fasting serum glucose X greater than 126 mg/dL)
• Hypercholesterolemia (serum levels greater than or equal to 240 mg/dL), hypertriglyceridemia (plasma levels greater than or equal to 220 mg/dL) and/or use of antilipemic therapy
• Liver disease or ALT serum level greater than two fold the upper laboratory reference limit
• Iron deficiency (Ferritin less than 40 ng/mL males, and less than 20 ng/mL females)
• Renal insufficiency or estimated creatinine clearance less than or equal to 50 mL/min (MDRD equation)
• Claustrophobia
• History of illicit drug or alcohol abuse within the last 5 years; current use of drugs (by history) or alcohol (CAGE greater than 3)
• Psychiatric conditions or behavior that would be incompatible with safe and successful participation in this study
• Current use of medications/dietary supplements/alternative therapies known to alter thyroid function
• Current use of antiplatelet or anticoagulants
• Allergy to lidocaine

Sponsors & Collaborators

• National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK): lead

Study Sites (1)

National Institutes of Health Clinical Center, 9000 Rockville Pike

Bethesda, Maryland, 20892, United States

Location

Related Publications (4)

• Hill JO. Understanding and addressing the epidemic of obesity: an energy balance perspective. Endocr Rev. 2006 Dec;27(7):750-61. doi: 10.1210/er.2006-0032. Epub 2006 Nov 22.

  PMID: 17122359 BACKGROUND

• Rosen ED, Spiegelman BM. Adipocytes as regulators of energy balance and glucose homeostasis. Nature. 2006 Dec 14;444(7121):847-53. doi: 10.1038/nature05483.

  PMID: 17167472 BACKGROUND

• Katzmarzyk PT, Leonard WR. Climatic influences on human body size and proportions: ecological adaptations and secular trends. Am J Phys Anthropol. 1998 Aug;106(4):483-503. doi: 10.1002/(SICI)1096-8644(199808)106:43.0.CO;2-K.

  PMID: 9712477 BACKGROUND

• Celi FS, Brychta RJ, Linderman JD, Butler PW, Alberobello AT, Smith S, Courville AB, Lai EW, Costello R, Skarulis MC, Csako G, Remaley A, Pacak K, Chen KY. Minimal changes in environmental temperature result in a significant increase in energy expenditure and changes in the hormonal homeostasis in healthy adults. Eur J Endocrinol. 2010 Dec;163(6):863-72. doi: 10.1530/EJE-10-0627. Epub 2010 Sep 8.

  PMID: 20826525 DERIVED

MeSH Terms

Conditions

Obesity; Thyroid Diseases

Condition Hierarchy (Ancestors)

Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Endocrine System Diseases

Study Officials

• Kong Y Chen, Ph.D.

  National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Purpose: OTHER
• Intervention Model: CROSSOVER
• Sponsor Type: NIH

Study Record Dates

• First Submitted: August 25, 2007
• First Posted: August 28, 2007
• Study Start: August 24, 2007
• Primary Completion: January 12, 2015
• Study Completion: June 26, 2018
• Last Updated: December 16, 2019

Record last verified: 2018-06-26

Locations

US (1)