Objectives: Defining clinically relevant outcome measures for Myotonic Dystrophy type 1 (DM1) that can be valid and feasible for different phenotypes has proven problematic. The Outcome Measures for Myotonic Dystrophy (OMMYD) group proposed a battery of
functional outcomes: six-minute walk test, 30 seconds sit and stand test, timed 10 m walk test, timed 10 m walk/run test and 9-hole peg test. This however required a large-scale
investigation. Methods: A cohort of 213 patients enrolled in the natural history study
PhenoDM1 were analysed in cross-sectional analysis and subsequently 98 patients were
followed for longitudinal analysis. We aimed to assess: [1] feasibility and best practice; [2]
intra-session reliability; [3] validity; and, [4] behaviour over time, of these tests. Results:
OMMYD outcomes proved feasible as 96% of the participants completed at least one trial for all tests and more than half (n=113) performed all three trials of each test. Body Mass Index (BMI) and disease severity associate with functional capacity. There was a significant difference between the 1st and 2nd trials of each test. There was a moderate to strong
correlation between these functional outcomes and muscle strength, disease severity and patient-reported outcomes. All outcomes after one year detected a change in functional capacity except the 9-hole peg test. Conclusions: These tests can be used as a battery of outcomes or independently based on the shown overlapping psychometric features and strong cross-correlations. Due to the large and heterogeneous sample of this study, these results can serve as reference values for future studies.
Aura C. Jimenez-Moreno, Nikoletta Nikolenko, Marie Kierkegaard, Alasdair P. Blain, Jane Newman, Charlotte Massey, Dionne Moat, Jas Sodhi, Antonio Atalaia, Grainne S. Gorman, Chris Turner, Hanns Lochmüller
Disease Category: Neurology
Disease Name: Myotonic dystrophy
Age Range: Unknown
Sex: Either
Nature of Intervention:
- Consumers (patients)
- Recommendations for outcome measures (measurement/how)
- Other
A cohort of 213 patients enrolled in the natural history study PhenoDM1 were analysed in cross-sectional analysis and subsequently 98 patients were
followed for longitudinal analysis. We aimed to assess: [1] feasibility and best practice; [2] intra-session reliability; [3] validity; and, [4] behaviour over time, of these tests.