95th Percentile Upper Limb Z-Axis Actigraph Activity and PUL Performance in Dystrophinopathy Patients


Translational Research

Poster Number: S67


Owen Glogovsky, BS, Rare Disease Research, Han Phan, MD, Rare Disease Research, Matthew Alexander, PhD, University of Alabama at Birmingham

The actigraph wrist device is currently used to assess the activity in study participants with notable use in sleep studies (Siegel, 2019). Wearable devices have recently received approval for use as an endpoint measure in clinical trials for patients diagnosed with Duchenne muscular dystrophy (DMD). These wearable devices assess the 95th percentile stride velocity of ambulatory subjects and these results are considered a potential substitute or complement to the 6 Minute Walk Test. Wearable devices offer a promising potential as an endpoint measure due to their lower sensitivity to evaluator bias, their lower reliance on patient motivation at the day of assessment, and the availability of larger datasets that capture real world performance (EMA, 2023). Using retrospective cohort data from actigraph measurements provided by the University of Alabama Birmingham School of Medicine’s MDA clinic, we have analyzed the potential for actigraph measures to evaluate the upper limb activity of individuals diagnosed with DMD. The actigraph results of 18 ambulant and non-ambulant participants between the ages of 8 and 21 was collected beginning in 2021 and is currently ongoing. Preliminary analysis of collected data has demonstrated a strong, statistically significant negative exponential relation between 95th percentile actigraph Z-Axis activity scores and participant age (Pearson correlation= -0.93; p<<0.05). Going forward, we hope to gather prospective observational data at our clinic where we will evaluate the potential usefulness of the actigraph wrist device as a measure of upper limb performance in ambulant and non-ambulant participants with DMD. We are looking to compare the PUL performance of participants to wrist actigraph Z-axis activity measures with the intention of evaluating the relationship between these two measures in order to propose the use of wrist actigraphy as an assessment of upper limb performance.