Variable Definitions
Outcomes. 1) FEV1 percent predicated (FEV1pp) (measured at admission, midpoint, discharge, hospital follow up). At admission values are typically in the clinic when decision to admit was made, midpoint was between 5-7 days after hospitalization, discharge reflects the day of discharge or 1-2 days prior, hospital follow-up was typically 4-6 weeks following discharge. We also evaluated restoring patients to their baseline FEV1pp after hospital admission for APE (discharge/baseline FEV1pp), and time to next APE compared to routine treatment. The baseline FEV1pp was the best value in the 12 months. A secondary outcome was length of hospital stay.
Steroids. Reason for steroid prescription was recorded; reasons documented included: poor improvement in FEV1pp, IgE elevation (but not ABPA diagnosis), previous positive response to steroids (FEV1pp).
Covariates. Demographic and additional clinical data collected included gender (male/female), genotype (dF508/dF508, dF508/other, other/other), length of stay, IgE values, antimicrobial treatment regimen, sputum culture data and best baseline spirometry.