Optimizing Vitamin D Status in Children With Wheeze / Asthma (OPTIVIT)
Condition: Asthmatic Crisis; Wheezing
MeSH terms: Status Asthmaticus; Respiratory Sounds
Study type: Interventional

Summary: 
      Vitamin D deficiency is highly prevalent in the UK. Research shows that vitamin D enhances
      the immune system and may help protect against chest infections that can cause wheezing
      illness or worsen asthma symptoms. The Department of Health recommends a dose of 10
      micrograms of vitamin D/day to prevent severe vitamin D deficiency in children. However, many
      studies have reported that this dose is not enough to raise plasma 25(OH)D concentration to
      the levels most likely to prevent against worsening of asthma symptoms. Such studies suggest
      that 25 micrograms of vitamin D/day. This dose is safe but its effects on vitamin D blood
      levels have not yet been specifically tested in children with asthma/wheeze. This study is
      designed to determine the optimal oral daily vitamin D supplementation dose to treat vitamin
      D deficiency in children with asthma or preschool wheeze. Over the 6-month course of the
      study, participants will meet with the study team four times in clinic or in their own home
      and will be contacted by telephone five times. Children will be asked to give a drop of blood
      via a fingerprick to test their vitamin D level and a sample of nasal epithelial lining fluid
      for measurement of inflammatory markers on three separate occasions.
    

Detailed description: 
      The study is designed to compare the efficacy of a daily oral vitamin D3 supplementation dose
      of 10 micrograms (400 IU) for 3 months vs a daily oral vitamin D3 supplementation dose of 25
      micrograms (1,000 IU) for an additional 3 months in correcting vitamin D deficiency in
      children with asthma or preschool wheezing illness.

      Identification procedures

      A member of the patient's usual care team will identify potentially eligible participants
      from patient records at participating sites. Identified individuals will be contacted by
      post, giving a brief explanation of the study and asking them to contact a member of the
      research team if they wish to find out more. A member of the research team will explain the
      study to them and ask them if they would like to receive the study participant information
      sheet (PIS). The PIS will be posted to patients expressing an interest in the study; those
      who subsequently confirm their interest in participation will be re-contacted by the study
      team, and offered a screening appointment at a study site. Additionally, posters advertising
      the study and providing contact details for the study team will be displayed in appropriate
      public places, such as hospital out-patient departments and General Practitioner (GP)
      surgeries, where potentially eligible participants are likely to see them; advertisements for
      the study may also be placed in the press, and circulated on email within Queen Mary,
      University of London. Potentially eligible children who fulfill eligibility criteria and give
      their assent (if aged ≥7 years) and have consent from their parent/legal guardian will be
      enrolled in the study.

      Study visits

      Visit 1 - Screening:

      Once the child and their parent/legal guardian decide to take part in the study and sign the
      agreement forms (assent and consent form), the investigators will record details of
      children's sociodemographic status, ethnicity, age and sex. The investigators will measure
      children's body weight and height, and ask children aged >= 5 years to fill in a
      questionnaire to assess their level of asthma symptom control. The investigators will then
      collect a drop of each child's blood with a finger-prick to measure his/her vitamin D level
      and a sample of fluid from one nostril of each child with a small (5 x 25 mm) strip of
      absorbent material to measure his/her inflammatory status. The investigators will apply a
      numbing cream or spray to each child's finger before the fingerprick to minimise discomfort.

      Telephone contact T1:

      The investigators will telephone children's parents/legal guardians to let them know the
      results of their child's baseline vitamin D test. If this is normal (75 nmol/L or more), then
      the child does not need a vitamin D supplement: the parent / guardian will be reassured, and
      the child will not be able to take part in this study. If the level is low, then the
      investigators will arrange to meet with the child and his/her parent/guardian a second time.

      Visit 2 - (1 week later):

      At this visit, the investigators will show children's parents/legal guardians how to give
      their child the study drops each day and also supply them with a bottle of vitamin D drops
      for their child to take every day at a dose of 6 drops (400 IU; 10 μg) per day. The
      investigators will also give them a diary where they can record the doses their child takes
      every day and note down details of unplanned visits to a doctor/nurse due to wheezing illness
      or worsening of asthma symptoms during the study.

      Telephone contact T2 - (One week after Visit 2):

      The investigators will telephone parents/legal guardians as arranged to check if their child
      is taking the study drops and to see how they are getting on. The investigators will also
      check if their child has made any unplanned visits to a doctor or a nurse due to wheezing
      illness or worsening of asthma symptoms since the last study visit.

      Telephone contact T3 - (Three weeks after telephone call T2):

      In this telephone call, the investigators will make the same checks as those in telephone
      contact T2.

      Visit 3 - (Month 3):

      In this visit, the investigators will perform the same tests as those in study visit 1. The
      investigators will take back the bottle with the remaining vitamin D liquid and the completed
      study diary, and provide a new diary and bottle with study drops.

      Telephone contact T4 - (One week after Visit 3):

      In this telephone call, the investigators will do the same checks as those in telephone call
      T2. The investigators will also let parents/legal guardians know results of their child's
      second vitamin D test. Based on this result, the investigators will decide if their child
      needs to increase the dose to 15 drops (1,000 IU; 25 μg) per day for a further 3 months or to
      continue with 6 drops (400 IU; 10 μg) per day for a further 3 months or to stop vitamin D
      supplementation.

      Telephone contact T5 - (Three weeks after telephone call T4):

      In this telephone call, the investigators will make the same checks as those in telephone
      contact T2.

      Visit 4 - FINAL VISIT - (Month 6):

      In this study visit, the investigators will perform the same tests as those in study visit 1.
      The investigators will ask parents/legal guardians to complete a final questionnaire about
      their child's experience in the study. The investigators will take back the bottle with the
      remaining study drops and the completed study diary. Once enrolment to the study and analysis
      of all study data is complete, the investigators will write to participants' parents/legal
      guardians to tell them about our final findings, including results of their child's final
      vitamin D test.

      Additional procedures throughout the study:

      Participants' parents/legal guardians will be asked to report the daily supplementation doses
      their child takes and record details of unplanned healthcare visits to a GP/nurse due to
      wheezing illness or worsening of asthma symptoms during the study.

      If a participant reports symptoms of raised blood calcium level during the study nausea,
      vomiting or feeling generally unwell), an urgent check of his/her corrected blood calcium
      level will be performed and an appointment with a pediatrician will be arranged if necessary.
    

Intervention name(s): Fultium-D3 drops (Internis)
Intervention type(s): Dietary Supplement
Intervention description(s): Oral daily doses of vitamin D3 (400 IU for 3 months; and 1,000 IU for an additional 3 months)
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: vitamin D