P.11.12 Pulmonary function characteristics of boys with Duchenne muscular dystrophy: Data from the CINRG longitudinal study project

The lack of well-characterized outcome measures in both ambulatory and non-ambulatory individuals with Duchenne Muscular Dystrophy limits the ability to show effectiveness during therapeutic clinical trials. The objective of this study is to determine whether changes in pulmonary function over a one-year period would have adequate sensitivity to be used as an endpoint for clinical trials in patients with DMD. PFTs were performed as part of a CINRG longitudinal study that included 341 individuals with confirmed DMD (ages 6 −28 years) in 20 centers from 10 countries. PFTs included forced vital capacity (FVC) and percent-predicted FVC (%FVC), forced expiratory volume in 1 s (FEV1) and %FEV1, peak expiratory flow rate (PEFR) and %PEFR, maximum inspiratory pressure (MIP) and %MIP, maximum expiratory pressure (MEP) and %MEP, peak cough flow (PCF) and %PCF. Significance was accepted at p 19. Over a one-year period, there were significant increases in the FVC, FEV1, and PEFR in each age group for children Pulmonary function testing reflects growth-associated increases in the absolute pulmonary capacity of younger boys with DMD as well as changes in the relative PFT performance when normalized using percent-predicted equations over a one-year period. These data suggest that percent predicted FVCs have the capacity to show change over time and will be useful outcome measures for clinical trials with DMD.