Study Results
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Basic Information
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COMPLETED
9700 participants
OBSERVATIONAL
2011-04-30
2016-08-31
Brief Summary
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Detailed Description
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The serum level of 25(OH)D, which is the metabolite used to evaluate a person's vitamin D status, is in part genetically determined and several polymorphisms with effects on serum 25(OH)D have been identified. These polymorphisms, where the minor allele frequencies vary between 16 and 40 %, appear as important for the serum 25(OH)D level as the effect of season, physical activity or vitamin D supplementation.
Vitamin D is not only vital for the skeleton, but appears to be related to a number of health outcomes, including mortality as previously demonstrated in the Tromsø study. However, as the serum level of 25(OH)D is strongly influenced by life-style factors that are also related to health outcomes, it is difficult to decide whether the relation between vitamin D and health is causal or not.
On the other hand, the polymorphisms are not influenced by life-style, and the effect of the polymorphisms will be life-long. Accordingly, they may be a better marker of vitamin D status than a single serum 25(OH)D measurement. Furthermore, there are a number of polymorphisms regarding the vitamin D receptor (VDR) that may be associated with health.
In the present study we will therefore relate the polymorphisms affecting the serum 25(OH)D level and the function of the VDR, with anthropometric and biochemical measures, mortality, diseases and risk factors for disease. DNA will be obtained from the 4th Tromsø study.
If we find the expected associations between the polymorphisms and diseases, this will further strengthen the role of vitamin D in human health, and may be important for recommendations regarding vitamin D supplementation. Considering the high prevalence of vitamin D deficiency world wide, this may potentially have huge consequences for public health.
The main purpose of the present study is the vitamin D system, but in the Tromsø study we have previously also found a number of associations between thyroid and androgen function and health. Obtaining DNA for analysis will be the major cost in the project, whereas analyses of individual polymorphisms are relatively cheap. We will therefore also include polymorphisms regarding thyroid and androgen function.
Conditions
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Keywords
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Study Design
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RETROSPECTIVE
Study Groups
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myocardial infarction
subjects with myocardial infarction in the Tromsø study end point registry
No interventions assigned to this group
type 2 diabetes
subjects with type 2 diabetes in the Tromsø study end point registry
No interventions assigned to this group
stroke
subjects with stroke in the Tromsø study end point registry
No interventions assigned to this group
fracture
subjects with fracture in the Tromsø study end point registry
No interventions assigned to this group
cancer
subjects with cancer in the Tromsø study end point registry
No interventions assigned to this group
death
subjects registered as dead in the Tromsø study end point registry
No interventions assigned to this group
aortic stenosis
subjects with aortic stenosis in the Tromsø study end point registry
No interventions assigned to this group
control group
randomly selected controls from the Tromsø study
No interventions assigned to this group
Eligibility Criteria
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Inclusion Criteria
Exclusion Criteria
30 Years
90 Years
ALL
Yes
Sponsors
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University of Tromso
OTHER
Responsible Party
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Rolf Jorde
Professor
Principal Investigators
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Rolf Jorde, Professor
Role: PRINCIPAL_INVESTIGATOR
University of Tromso
Locations
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University of Tromsø
Tromsø, Tromsø, Norway
Countries
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References
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Jorde R, Schirmer H, Wilsgaard T, Joakimsen RM, Mathiesen EB, Njolstad I, Lochen ML, Figenschau Y, Berg JP, Svartberg J, Grimnes G. Polymorphisms related to the serum 25-hydroxyvitamin D level and risk of myocardial infarction, diabetes, cancer and mortality. The Tromso Study. PLoS One. 2012;7(5):e37295. doi: 10.1371/journal.pone.0037295. Epub 2012 May 23.
Other Identifiers
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UIT-ENDO-2011-2
Identifier Type: -
Identifier Source: org_study_id