The following is a summary of “Lessons for future clinical trials in adults with Becker muscular dystrophy: Disease progression detected by muscle magnetic resonance imaging, clinical and patient-reported outcome measures,” published in the March 2024 issue of Neurology by Wel et al.

Researchers started a retrospective study to address the gap in outcome measure evaluation for adult Becker muscular dystrophy (BMD), a disease with variable progression.

They assessed muscle MRI, patient-reported outcomes (PROs), and various clinical measures (Motor Function Measurement (MFM), muscle strength, and timed-function tests) in 21 adults diagnosed with BMD at the beginning of the study and at 9 and 18 months into the follow-up period.

The results showed a significant increase in proton density fat fraction in 10 out of 17 thigh muscles after 9 months and in all thigh and lower leg muscles after 18 months. The 32-item MFM-32 scale showed a decrease of 1.3% (P=0.017), North Star Ambulatory Assessment decreased by 1.3 points (P=0.010), and the patient-reported activity limitations scale deteriorated by 0.3 logits (P=0.018) after 9 months. After 18 months, the 6-minute walk distance decreased by 28.7 meters (P=0.042), 10-meter walking test decreased by 0.1 meters per second (P=0.032), time to climb four stairs test decreased by 0.03 meters per second (P=0.028), and Biodex peak torque measurements of quadriceps decreased by 4.6 Nm (P=0.014) and hamstrings by 5.0 Nm (P=0.019). MFM-32 domain 1 had the highest sensitivity to change, with a standardized response mean of 1.15.

Investigators concluded that whole-thigh PDFF MRI was sensitive to BMD muscle fat changes and that MFM-32 was the most responsive clinical measure.

Source: onlinelibrary.wiley.com/doi/full/10.1111/ene.16282