Trial of Vitamin D Supplementation for the Prevention of Influenza and Other Respiratory Infections (ViDiFlu)

Study Overview
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Brief Summary
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Purpose: The study null hypothesis is that vitamin D supplementation will not influence time to acute respiratory tract infection in sheltered accommodation residents.

Detailed Description
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The study population will comprise sheltered accommodation residents and staff fulfilling eligibility criteria. Half of the sheltered accommodation schemes will be randomly allocated to 2-monthly oral bolus vitamin D supplementation (Vigantol oil) over a period of one year, and half to placebo. Participants will be followed for one year.

Official Title
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Cluster-randomised, Double-Blind, Placebo-Controlled Trial of Vitamin D Supplementation for the Prevention of Influenza and Other Respiratory Infections in Sheltered Accommodation (ViDiFlu)

Conditions
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Respiratory Tract Infections, Influenza

Intervention / Treatment
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* Dietary Supplement: Cholecalciferol (Vitamin D/Vigantol oil)
* Dietary Supplement: Miglyol oil


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Permanent resident or member of staff at sheltered accommodation unit If a woman of child-bearing potential, is sexually abstinent or has negative pregnancy test within 7 days of recruitment and agrees to use reliable form of contraception until she has completed the study Able to give written informed consent to participate Age ≥ 16 years on day of first dose of IMP Exclusion Criteria: Current diagnosis of asthma or chronic obstructive pulmonary disease Chronic upper or lower respiratory infection or other condition causing chronic cough Condition requiring treatment with vitamin D at a dose of > 10 micrograms vitamin D/day Episode of upper or lower respiratory tract infection up to 28 days before first dose of IMP Known sarcoidosis, hyperparathyroidism, nephrolithiasis, active tuberculosis, vitamin D intolerance, liver failure, renal failure, terminal illness, lymphoma or other malignancy not in remission at time of recruitment Taking benzothiadiazine derivative, cardiac glycoside, carbamazepine, phenobarbital, phenytoin, primidone or long-term immunosuppressant therapy Taking oral preparation containing > 10 micrograms vitamin D/day up to 2 months before first dose of IMP Using topical vitamin D analogue Treatment with any investigational medical product or device up to 4 months before first dose of IMP Breastfeeding, pregnant or planning a pregnancy Baseline corrected serum calcium > 2.65 mmol/L Baseline serum creatinine > 125 micromol/L Inability to complete symptom diary with / without assistance Cognitive impairment or communication problem precluding informed consent or successful completion of study evaluations

Ages Eligible for Study
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Minimum Age: 16 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Miglyol oil<br>Miglyol oil will be administered in 2-monthly oral bolus doses over a period of one year | Dietary Supplement: Miglyol oil<br>* Miglyol oil will be administered as 2-monthly oral bolus doses of Miglyol oil over a period of one year<br>|
| Active Comparator: Vigantol oil<br>Vigantol oil will be administered in 2-monthly oral bolus doses over a period of one year | Dietary Supplement: Cholecalciferol (Vitamin D/Vigantol oil)<br>* Cholecalciferol will be administered as 2-monthly oral bolus doses of Vigantol oil over a period of one year<br>* Other names: Vigantol oil;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to first respiratory tract infection (upper or lower) in sheltered accommodation residents |  | One year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to first respiratory tract infection (upper or lower) in sheltered accommodation staff |  | One year | 
| Annual rate of episodes of upper / lower respiratory infection in sheltered accommodation residents / staff |  | One year | 
| Time to unscheduled health service use for respiratory tract infection in sheltered accommodation residents / staff |  | One year | 
| Proportion of participants experiencing hypercalcaemia |  | One year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Bone Density Conservation Agents, Cholecalciferol, Communicable Diseases, Growth Substances, Housing for the Elderly, Infection, Micronutrients, Pharmacologic Actions, Physiological Effects of Drugs, Respiratory Tract Diseases, Vitamins, Respiratory Tract Infections/prevention & control*, Vitamin D