Longitudinal Follow-up of Brown Adipose Tissue Function and Structure

Study Overview
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Brief Summary
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In Turku PET Centre, there have been 3 positron emission tomography studies on brown adipose tissue (BAT) activity in healthy adults. BATPET was performed between 2008 and 2009. FATBAT started in 2011 and Dixon-BAT in 2012 and they are both currently ongoing. In the current study, participants of BATPET, FATBAT and Dixon-BAT studies are recruited for a follow-up study to examine associations between obesity, cardiovascular risk factors, serum metabolic profile and BAT structure at baseline and during follow-up several years later. 43 BATPET participants will be called for follow-up in 2013 with a follow-up period of 5 years and 52 FATBAT and Dixon-BAT participants in years 2014 and 2015 with a follow-up period of 3 years. The aim of this study is to examine longitudinal associations between BAT function and structure, liver adiposity and cardiovascular risk factors at baseline and during follow-up.

Official Title
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Brown Adipose Tissue: Longitudinal Follow-up of Brown Adipose Tissue Structure and Associations With Obesity and Cardiovascular Risk Factors in Healthy Participants of Baseline PET Studies (BAT-Follow-Up)

Conditions
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Obesity

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All study subjects have been screened prior to acceptance in BATPET, FATBAT and Dixon-BAT studies and no screening for inclusion is required in the current study. Exclusion Criteria: 1) Smoking 2) Blood pressure > 160/100 mmHg 3) Pregnancy or lactation 4) Medication (expected effect on study variables)

Ages Eligible for Study
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Minimum Age: 22 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Phase 1 group<br>Subjects were studied in 2009 and their follow-up is in 2014. | |
| Phase 2 group<br>Subjects were studied in 2011 and their follow-up is in 2016. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between baseline brown adipose tissue activity according to PET imaging and serum lipoprotein concentrations at follow-up 5 years later | Brown adipose tissue activity is determined with FDG-PET imaging at baseline in 43 subjects and 5 years later the subjects participate a follow-up visit where lipoprotein levels are measured in mmol/l from serum samples. Correlation between brown adipose tissue activity and serum lipoproteins are examined with Pearson's correlation. | 5 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Association between brown adipose tissue structure at baseline and at follow-up |  | 5 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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positron emission tomography, magnetic resonance imaging, brown adipose tissue, obesity, cardiovascular disease, subclinical atherosclerosis