Seasonal Variations in Serum 25-hydroxy Vitamin-D Levels in a Swedish Cohort

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT02136407

Enrollment

615

Registered

2014-05-13

Start date

2009-10-31

Completion date

2010-09-30

Last updated

2014-05-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Vitamin-D Insufficiency

Keywords

Vitamin D, vitamin D deficiency, parathyroid hormone

Brief summary

The purpose of this study was to study seasonal inter-individual and intra-individual variations in S-25(OH)D and to explore parameters associated with S-25-OHD in healthy Swedish adults.

Detailed description

Serum was collected during 12 months and analysed for 25(OH)D in 540 healthy blood donors. The blood donors answered questionnaires concerning vitamin D supplements, smoking, physical activity, sunbed use and holidays in sunny locations. Repeated serum samples were also collected from thrombocyte donors to study the intra-individual variations in S-25(OH)D.

Interventions

None listed

Study design

Observational model

COHORT

Time perspective

CROSS_SECTIONAL

Eligibility

Sex/Gender

ALL

Age

16 Years to 75 Years

Healthy volunteers

Yes

Inclusion criteria

* healthy at the time of donating blood

Exclusion criteria

* unhealthy

Design outcomes

Primary

Measure	Time frame
Inter-individual and intra-individual varations in serum 25-hydroxy vitamin-D during different seasons.	Group1:Blood donors, single test, 25(OH)vit D at inclusion . Group 2: thrombocyte donors: multiple tests, serum 25(OH)vit D during 8 months.

Countries

Sweden

Outcome results