Clinical Trial: Assessment Of Vitamin D Role In The Pathogenesis Of Asthma In Vitamin D Resistent Patients

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Assessment Of Vitamin D Role In The Pathogenesis Of Asthma In Vitamin D Resistent Patients

Brief Summary:

Research Title: Evaluation of airway reactivity, allergy and inflammatory mediators in exhaled breath condensate in vitamin D resistant rickets.

Aim: To assess the effect of absence of vitamin D receptors on airway reactivity, allergy and inflammatory mediators in exhaled breath condensate in a prospective study evaluating patients with vitamin D resistant rickets and in healthy controls.

Sample size: 40 participants in the two groups. Primary end point: Airway reactivity as assessed by methacholine challenge test.

Secondary outcome parameters: All other parameters are the secondary end points.


Detailed Summary:

Research Title: Evaluation of airway reactivity, allergy and inflammatory mediators in exhaled breath condensate in vitamin D resistant rickets.

Introduction: Vitamin D seems to play a role in allergic and asthmatic reactions. Vitamin D resistant rickets patients lack vitamin D receptors and cannot absorb vitamin D.

Aim: To assess the effect of absence of vitamin D receptors on airway reactivity, allergy and inflammatory mediators in exhaled breath condensate.

Design: Prospective study evaluating these parameters in patients with vitamin D resistant rickets and in healthy controls.

Participant selection: The study group will consist of vitamin D resistant rickets patients followed and treated at the Pediatric Endocrinology Department at our hospital. The study group will be compared to an age- and sex-matched healthy control group that had a negative methacholine challenge test.

Sample size: 40 participants in the two groups. Intervention: Each subject will undergo evaluation including a respiratory questionnaire, pulmonary function tests, methacholine challenge test with determination of PC20, exhaled nitric oxide (eNO), and exhaled breath condensate (EBC). Venous blood will be analyzed for complete blood count + eosinophils, IGE levels, and Vitamin D levels. Prick skin test for inhaled allergens will be performed. All measurements will be evaluated in a single 3 hour visit, with no follow up study visits.

Primary end point: Airway reactivity as assessed by methacholine challenge test.

Secondary outcome parameters: All other parameters are the secondary end points.


Sponsor: Rambam Health Care Campus

Current Primary Outcome: Metacholine Challenge Test [ Time Frame: participants will be followed for the duration of hospital visit, an average of 3 hours ]

As assessed by methacholine challenge test with determination of PC20.


Original Primary Outcome: Metacholine Challenge Test [ Time Frame: baseline ]

As assessed by methacholine challenge test with determination of PC20.


Current Secondary Outcome:

  • IgE [ Time Frame: participants will be followed for the duration of hospital visit, an average of 3 hours ]
    in peripheral Blood count
  • CBC [ Time Frame: participants will be followed for the duration of hospital visit, an average of 3 hours ]
    in peripheral Blood count
  • Fractional Exhaled NO [ Time Frame: participants will be followed for the duration of hospital visit, an average of 3 hours ]
    determination of exhaled NO in Exhaled breath
  • skin tests for inhaled allergens [ Time Frame: participants will be followed for the duration of hospital visit, an average of 3 hours ]
  • Inhaled breath condensate [ Time Frame: participants will be followed for the duration of hospital visit, an average of 3 hours ]
  • C reactive protein [ Time Frame: participants will be followed for the duration of hospital visit, an average of 3 hours ]
    in peripheral Blood count
  • 25 OH vitamin D3 [ Time Frame: participants will be followed for the duration of hospital visit, an average of 3 hours ]
    in peripheral Blood count


Original Secondary Outcome:

  • IgE [ Time Frame: baseline ]
    in peripheral Blood count
  • CBC [ Time Frame: baseline ]
    in peripheral Blood count
  • Fractional Exhaled NO [ Time Frame: baseline ]
    determination of exhaled NO in Exhaled breath
  • skin tests for inhaled allergens [ Time Frame: baseline ]
  • Inhaled breath condensate [ Time Frame: baseline ]
  • C reactive protein [ Time Frame: baseline ]
    in peripheral Blood count
  • 25 OH vitamin D3 [ Time Frame: baseline ]
    in peripheral Blood count


Information By: Rambam Health Care Campus

Dates:
Date Received: November 9, 2011
Date Started: March 2011
Date Completion:
Last Updated: June 12, 2013
Last Verified: June 2013