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Vitamin D DeficiencyD-tectNCT03330301

D-tecting Disease - From Exposure to Vitamin D During Critical Periods of Life

An observational study of Vitamin D Deficiency and Obesity, run by Bispebjerg Hospital at 1 site in Denmark.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

Vitamin D deficiency is common among otherwise healthy pregnant women and may have consequences for them as well as the early development and long-term health of their children. However, the importance of maternal vitamin D status has not been widely studied. Read more about this study

Who is it for?
Any age
Conditions the study is for
Vitamin D Deficiency, Obesity, Diabetes Mellitus
What is being tested?
D-tect
How many people
222,776 participants
Where
1 siteDenmark
Study dates
1 Apr 2012to 30 Sep 2016
How long will I take part?
33 Years
Phase
Observational
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages Any age
  • All sexes
  • Child, Adult, Older adult

Study population: Entire Danish population born between June1983-May1985 and September 1986-August 1988. For the part of the study using vitamin D measurements from DBS: The Danish Civil registration system was used to identify all live-born children during 1981-2002 (n = 1,360,466), and a random subcohort thereof was sampled for 25(OH)D analyses to be used across the D-tect studies (n = 3585)

Who may be able to join

  • Born in Denmark around the fortification period
  • Sufficient amount of blood from the DBS

Who cannot join

  • 1.Born outside Denmark
  • Born outside the fortification period
  • Insufficient amount of blood from the DBS or DBS not found

Trial locations and contacts

1 site in 1 country.

Denmark1 site
  • Parker Institute

    Frederiksberg, 2000

Other trials in Denmark

About this study

Vitamin D deficiency is common among otherwise healthy pregnant women and may have consequences for them as well as the early development and long-term health of their children. However, the importance of maternal vitamin D status has not been widely studied.

The present study is divided into a societal experiment (1) and a case-cohort study (2):

Read more
  1. The present study includes an in-depth examination of the influence of exposure to vitamin D early in life and during critical periods of growth for development of type 1 diabetes (T1D), type 2 diabetes, gestational diabetes, pre-eclampsia, obesity, asthma, arthritis, cancer, mental and cognitive disorders, congenital disorders, dental caries and bone fractures during child- and adulthood. The study is based on the fact that mandatory fortification of margarine with vitamin D, which initiated in 1937, was terminated in 1985. Apart from determining the influences of exposure prior to conception and during pre- and postnatal life, the investigators examined the importance of vitamin D exposure during specific seasons and trimesters, by comparing disease incidence among individuals born before and after the fortification.
  2. Additionally, a validated method was used to determine neonatal vitamin D status using stored dried blood spots (DBS) from individuals who develop the aforementioned disease entities as adults and their time and gender-matched controls.

Unparalleled, the study will help determine the effects of vitamin D exposure during critical periods in life. There are a sufficient number of individuals to verify any effects during different gestation phases and seasons of the year. The results, which will change our current understanding of the significance of vitamin D, will enable new research in related fields, including interventional research designed to assess supplementation needs for different subgroups of pregnant women. Also, other health outcomes can subsequently be studied to generate multiple new interdisciplinary health research opportunities involving vitamin D.

Being tested
D-tect
Medical subject headings
Vitamin D Deficiency, Obesity, Diabetes Mellitus, Pre-Eclampsia, Arthritis, Asthma, Fractures, Bone, Tooth Diseases

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • D-tectOther

    1. This study is based on a unique Danish social experiment that took place during a well-defined period between 1937 and December 1985, when it was mandatory to fortify all margarine with vitamin D (1.25 μg/100 g). This well-defined vitamin D fortification period makes it possible to investigate the impact of fetal exposure to extra vitamin D from food fortification on the risk of developing diseases later on. This study is possible due not only to the well-defined adjacent time window but also to the complete registration of every citizen via a civil registration number. This number can be linked, on an individual level, to Danish birth, patient and medical registries; social and ethnic registries; and clinical and other large databases
    2. Case-cohort study: vitamin D measurements from dried blood spots and the risk of diseases later on
Study groups in NCT03330301
Study groupRoleWhat they receive
Exposed1. Individuals born between June1983 and May1985 were exposed to the mandatory vitamin D margarine fortification during fetal life. 2. Cases: individuals defined as having one of the aforementioned diseases of interest from the registers
Receives: Other: D-tect
Non-exposed1. Individuals born between September1986 and August 1988 were not exposed to the mandatory vitamin D margarine fortification during fetal life. 2. Controls: cohort of matched disease-free individuals
Receives: Other: D-tect

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Obesity

    Register based

    Measured: 2012-2025

  2. Type 1 diabetes

    Register based

    Measured: 2012-2016

  3. Pre-eclampsia

    Register based

    Measured: 2012-2025

  4. Bone facture

    Register based

    Measured: 2012-2025

Secondary outcomes (6)
  1. Type 2 diabetes

    Register based

    Measured: 2014-2025

  2. Gestational diabetes

    Register based

    Measured: 2014-2025

  3. Asthma

    Register based

    Measured: 2015-2025

  4. Arthritis

    Register based

    Measured: 2018-2025

  5. Birth weight

    Register based

    Measured: 2014-2019

  6. Mental diseases

    Register based

    Measured: 2012-2025

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted6 Nov 2017
  2. Study start1 Apr 2012
  3. Primary completion30 Sep 2016
  4. Study completion30 Sep 2016

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Observational
Observational model
Ecologic or community
Time perspective
Prospective
Enrolment
222,776 participants (actual)
Target duration
33 Years
IDs, dates and publications
ClinicalTrials.gov ID
NCT03330301
Sponsor's protocol ID
0603-00453B
Acronym
D-tect
Status last verified
Nov 2017
First submitted
31 Oct 2017
Last updated
6 Nov 2017
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Publications

  • Keller A, Stougard M, Frederiksen P, Thorsteinsdottir F, Vaag A, Damm P, Jacobsen R, L Heitmann B. In utero exposure to extra vitamin D from food fortification and the risk of subsequent development of gestational diabetes: the D-tect study. Nutr J. 2018 Nov 2;17(1):100. doi: 10.1186/s12937-018-0403-5.

    PubMed 30388966

Questions about this trial

What is this clinical trial studying?

An observational study of Vitamin D Deficiency and Obesity, run by Bispebjerg Hospital at 1 site in Denmark.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 2 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 6 Nov 2017. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Denmark. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Obesity (time frame: 2012-2025). The study lists 4 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT03330301, which also lists 1 linked publication.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Nov 2017.

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