Determinants of Early Cystic Fibrosis Lung Disease
Condition: Cystic Fibrosis in Children
MeSH terms: Cystic Fibrosis; Lung Diseases; Pulmonary Fibrosis; Fibrosis
Study type: Observational

Summary: 
      The overall objective of this study is to determine the impact early nutritional and
      respiratory indices have on early CF lung disease. This knowledge will guide clinical
      management of infants with CF, who are now primarily diagnosed through newborn screening.
    

Detailed description: 
      The overall objective of this study is to determine the impact early nutritional and
      respiratory indices have on early CF lung disease. This knowledge will guide clinical
      management of infants with CF, who are now primarily diagnosed through newborn screening. We
      hypothesize that respiratory and nutritional indices during the first year of life are
      critical determinants of lung function in infants and preschoolers with CF.

      Aim #1 - To examine the relationship between nutritional status (weight-for-age (WFA) and
      weight-for-length (WFL)) at 6 months of age and lung function at 1-2 years of age in infants
      with CF.

      Hypothesis: Infants with CF with poor nutritional status at 6 months of age will have worse
      lung function, as assessed through the raised volume rapid thoracoabdominal compression
      technique and plethysmography, compared to those with better nutritional indices, defined as
      improved weight-for-age and weight-for-length.

      Aim #2 - To examine the relationship between nutritional status (WFA and WFL) in infants with
      CF at 12 months of age and the lung clearance index (LCI) at 3-5 years of age.

      Hypothesis: Infants with CF with poor nutritional indices at 12 months of age will have a
      higher (worse) LCI at 3-5 years of age compared to those with better nutritional status.

      Aim #3 - To delineate the relationship between passive tidal breathing lung function testing
      in infants with CF at 4-8 weeks of age and subsequent lung function at 6-12 months of age.

      Hypothesis: Abnormalities in passive tidal breathing lung function testing will be associated
      with abnormal infant pulmonary function testing obtained via the raised volume rapid
      thoracoabdominal compression technique and plethysmography at 6-12 months of age.
    

Intervention name(s): Infant PFT; Lung Clearance Index; Passive tidal breathing
Intervention type(s): Diagnostic Test; Diagnostic Test; Diagnostic Test
Intervention description(s): Assessed through the raised volume rapid thoracoabdominal compression technique and plethysmography; The Lung Clearance Index is derived from the Multiple Breath Washout test. It is the cumulative exhaled volume (the volume of gas needed to wash out resident gas mixture out of the lungs) divided by the FRC. The FRC is the amount of air left in the lungs after normal exhalation.; During quiet sleep, tidal breathing flow-volume curves are obtained. The tPEF/tE is calculated by taking the time it takes to reach peak expiratory flow divided by the total peak expiratory time.
Observational model: Cohort
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Infants and preschoolers with cystic fibrosis diagnosed by newborn screen.
      
Keywords: Nutritional Status; Infant Pulmonary Function Testing; Lung Clearance Index; Multiple Breath Washout