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Vitamin D3 Supplementation to Prevent Respiratory Tract Infections

Vitamin D3 Supplementation to Prevent Respiratory Tract Infections, Including Covid-19, in Hospital Workers: a Pragmatic Study

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04596657
Enrollment
877
Registered
2020-10-22
Start date
2020-10-27
Completion date
2023-10-19
Last updated
2023-12-08

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

Conditions

Covid19, Flu Like Illness, Respiratory Tract Infections

Brief summary

The Cooper vitamin D3 study is a randomized study investigating whether daily vitamin D3 supplementation can prevent respiratory tract infections, influenza-like illness and covid-19 in hospital workers.

Detailed description

Influenza-like illness and covid-19 were added to this summary because the protocol uses respiratory tract infections and influenza-like illness interchangeably. Influenza-like illness is more accurate. Protocol amendments: Protocol title was amended to include covid-19. Minimum age was changed from 52 to 18, expanding the sample size. Exclusion criteria re vitamin D intake was changed from \>5000 to \>=5000 IU.

Interventions

DIETARY_SUPPLEMENTVitamin D supplementation

Daily vitamin D3 supplementation (5000 IU)

Sponsors

Won Sook Chung Foundation
CollaboratorUNKNOWN
The Cooper Health System
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

* Hospital worker * Age 18 years or older

Exclusion criteria

* History of hypercalcemia * History of nephrolithiasis * History of intolerance to vitamin D3 supplements * Use of calcium at a dose \> 600 mg/day (individuals using a dose greater than 600 mg of calcium per day will be asked to limit the amount to 600 mg unless they have been directed by their physician to be taking more than 600 mg/day of calcium. If the latter is true the potential subject will be excluded from the study.) * Use of vitamin D at a daily dose \> 5000 IU\* * Use of aluminum-containing phosphate binders in patients with renal failure * Use of calcipotriene * Use of digoxin * Use of thiazide diuretics if using: * hydrochlorothiazide at a daily dose \> 37.5 mg * indapamide at a daily dose \> 1.25 mg * chlorthalidone at a daily dose \> 12.5 mg * metolazone at a daily dose \> 2.5 mg * methyclothiazide at a daily dose \> 2.5 mg * chlorothiazide at a daily dose \> 250 mg * metolazone at a daily dose \> 0.5 mg * bendroflumethiazide at a daily dose \> 2.5 mg * polythiazide at a daily dose \> 1 mg * hydroflumethiazide at a daily dose \> 25 mg * Conditions that are associated with a risk of modified vitamin D metabolism * Known allergy to wool * Current enrollment in another study * Life expectancy \<1 month at time of screening * Cognitive impairment precluding the ability to provide informed consent * Pregnant or trying to become pregnant * Employee is team member on the present study * If potential participants are found to be using vitamin D supplementation upon screening at a daily dose ≤5000 IU/day, they will be eligible for participation by switching to the study dose. If potential participants are taking a multiple vitamin or calcium supplement and there is less than or equal to 800 IU vitamin D in it, they can continue the multivitamin or calcium supplement along with taking the study vitamin D3. Total vitamin D cannot exceed 5,800 IU per day combined between any supplements that contain vitamin D. Use of vitamin D at a daily dose \> 5000 IU at the direction of a physician will be an exclusion criterion. If a potential subject uses over-the-counter vitamin D not directed by a physician at a daily dose \> 5000 IU they will be eligible to participate by switching to the lower study dose.

Design outcomes

Primary

MeasureTime frameDescription
Influenza-like illness9 monthsIncidence of influenza-like illness

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026