The effect of cold exposure on the glycaemic and insulinaemic responses to an oral glucose load

Recruitment & Eligibility

Status: Completed

Sex: Not specified

Target Recruitment: 32

Inclusion Criteria

Inclusion Criteria of healthy population (n<=16):;Signed informed consent.
White European.
Male.
Age 18 - 40 years at the start of the study.
BMI * 20 and < 30 kg/m2.;Inclusion criteria of impaired glucose metabolism population (n<=16):;Signed informed consent.
White European.
Male or female.
Women should be postmenopausal or use hormonal contraconceptives.
Age 30 * 75 years at the start of the study.
BMI * 25 and <35 kg/m2.
Generally healthy, no medication use that interferes with metabolism. If volunteers need medication (e.g. statin drugs, NSAIDs), it will be reviewed with the dependent physician on an individual basis.
Impaired fasting glucose (5.6 mM to 6.9 mM) and/or blood glucose values 7.8-11.0 mM 2h after glucose drink consumption during OGTT in screening, based on the criteria set by the American Diabetes Association.

Exclusion Criteria

Healthy population exclusion criteria:;Smoking.
Active diseases (cardiovascular, diabetes mellitus, liver, kidney, cancer or *other).
Cold-acclimated, such as takes daily cold showers or baths, or works in a refrigerated environment, or visit of a place with cold climate (e.g. skiing holiday), within 1 month previous to the start of the study.
Unstable body weight (gain or loss > 5kg in last 3 months).
Currently undertaking a diet.
Hb <8.4 mmol/L.
Performs strenuous exercise on most days of the week.;Impaired glucose metabolism population exclusion criteria:;Smoking.
Active diseases (cardiovascular, diabetes mellitus, liver, kidney, cancer or *other).
Cold-acclimated, such as takes daily cold showers or baths, or works in a refrigerated environment, or visit of a place with cold climate (e.g. skiing holiday), within 1 month previous to the start of the study.
Unstable body weight (gain or loss > 5kg in last 3 months).
Currently undertaking a diet.
Men: Hb <8.4 mmol/L, Women: Hb <7.8 mmol/L. *
Performs strenuous exercise on most days of the week.

Study & Design

Study Type: Interventional

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
<p>The primary research parameters are the changes in glucose and insulin<br /><br>concentrations after the oral glucose tolerance test.</p><br>

Secondary Outcome Measures

Name	Time	Method
<p>Exploratory parameters:<br /><br>Energy expenditure (using indirect calorimetry)<br /><br>Shivering activity (using surface electromyography)<br /><br>Core (using a telemetric pill) and skin temperatures (using iButtons)<br /><br>Skin blood flow (using laser doppler flowmetry)<br /><br>Thermal sensation and comfort (using questionnaires)<br /><br>Blood pressure and heart rate (using automatic blood pressure cuff and a heart<br /><br>rate band)<br /><br>Plasma glucose, lactate, adrenaline and noradrenaline in response to cold<br /><br>exposure<br /><br>Plasma volume changes (using haematocrit and haemoglobin values)</p><br>