NCT03330301

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

  1. 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.
  2. 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.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
222,776

participants targeted

Target at P75+ for all trials

Timeline
Completed

Started Apr 2012

Longer than P75 for all trials

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

April 1, 2012

Completed
4.5 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

September 30, 2016

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

September 30, 2016

Completed
1.1 years until next milestone

First Submitted

Initial submission to the registry

October 31, 2017

Completed
6 days until next milestone

First Posted

Study publicly available on registry

November 6, 2017

Completed
Last Updated

November 6, 2017

Status Verified

November 1, 2017

Enrollment Period

4.5 years

First QC Date

October 31, 2017

Last Update Submit

November 2, 2017

Conditions

Outcome Measures

Primary Outcomes (4)

  • Obesity

    Register based

    2012-2025

  • Type 1 diabetes

    Register based

    2012-2016

  • Pre-eclampsia

    Register based

    2012-2025

  • Bone facture

    Register based

    2012-2025

Secondary Outcomes (6)

  • Type 2 diabetes

    2014-2025

  • Gestational diabetes

    2014-2025

  • Asthma

    2015-2025

  • Arthritis

    2018-2025

  • Birth weight

    2014-2019

  • +1 more secondary outcomes

Other Outcomes (4)

  • Cancers

    2018-2025

  • Mental disorders

    2018-2025

  • Dental caries

    2018-2025

  • +1 more other outcomes

Study Arms (2)

Exposed

1. 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

Other: D-tect

Non-exposed

1. 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

Other: D-tect

Interventions

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

ExposedNon-exposed

Eligibility Criteria

Sexall
Age GroupsChild (0-17), Adult (18-64), Older Adult (65+)
Sampling MethodProbability Sample
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)

You may qualify if:

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

You may not qualify if:

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

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Parker Institute

Frederiksberg, 2000, Denmark

Location

Related Publications (1)

  • 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.

Related Links

MeSH Terms

Conditions

Vitamin D DeficiencyObesityDiabetes MellitusPre-EclampsiaArthritisAsthmaFractures, BoneTooth DiseasesBirth WeightCongenital, Hereditary, and Neonatal Diseases and AbnormalitiesPregnancy ComplicationsMental DisordersNeoplasms

Interventions

Cari-D-Tect

Condition Hierarchy (Ancestors)

AvitaminosisDeficiency DiseasesMalnutritionNutrition DisordersNutritional and Metabolic DiseasesOverweightOvernutritionBody WeightSigns and SymptomsPathological Conditions, Signs and SymptomsGlucose Metabolism DisordersMetabolic DiseasesEndocrine System DiseasesHypertension, Pregnancy-InducedFemale Urogenital Diseases and Pregnancy ComplicationsUrogenital DiseasesJoint DiseasesMusculoskeletal DiseasesBronchial DiseasesRespiratory Tract DiseasesLung Diseases, ObstructiveLung DiseasesRespiratory HypersensitivityHypersensitivity, ImmediateHypersensitivityImmune System DiseasesWounds and InjuriesStomatognathic Diseases

Study Design

Study Type
observational
Observational Model
ECOLOGIC OR COMMUNITY
Time Perspective
PROSPECTIVE
Target Duration
33 Years
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Professor

Study Record Dates

First Submitted

October 31, 2017

First Posted

November 6, 2017

Study Start

April 1, 2012

Primary Completion

September 30, 2016

Study Completion

September 30, 2016

Last Updated

November 6, 2017

Record last verified: 2017-11

Data Sharing

IPD Sharing
Will not share

Locations