Key Points
- To determine whether boys with Duchenne muscular dystrophy carrying distinct mutation types demonstrate different rates of change on the 6-minute walk test over a 12-month period.
- Assessed 191 ambulant boys with Duchenne muscular dystrophy using the 6-minute walk test at baseline and at 12-month follow-up.
- Conducted heterogeneity testing to compare functional changes across mutation types (deletions, duplications, point mutations) and specific exon-skipping categories (exons 44, 45, and 53).
- Baseline 6-minute walk distance ranged from 180 to 560.80 meters (mean 378.06, SD 74.13), while 12-month changes ranged from -325 to 175 meters (mean -10.8 meters, SD 69.2).
- Patients with duplications and those eligible for exon 44 skipping showed slightly higher baseline distances and smaller declines than other groups, but differences across mutation subgroups were not statistically significant.
- Mean 12-month changes for each mutation subgroup remained within a narrow range around the overall cohort mean of -10.8 meters.
Structured PICO
PPopulation191 ambulant boys with Duchenne muscular dystrophy (DMD)
OOutcomeChanges on the 6 minute walk test (6MWT) over a 12 month periodsurrogate
In ambulant boys with DMD, 12-month changes in 6MWT do not significantly differ by mutation type, providing important natural history data for designing clinical trials.