Duchenne muscular dystrophy (DMD) is a multiorgan genetic disease affecting the brain, cardiac and skeletal muscles. Although disease-modifying therapies have changed the natural history in DMD, long-term health outcomes continue to be suboptimal. Extant studies have shown that functional motor outcomes are influenced by social drivers. The influence of social drivers of brain health in DMD is unexplored.
A prospective observational cohort of 65 boys with DMD (ages 4-22) were assessed using age-appropriate NIH Toolbox Cognition Battery (NIHTB-CB). As part of study records, DMD variant information and residential zip-code information were collected. The latter was used to evaluate community-level disadvantage using the CDC’s Social Vulnerability Index (SVI), a geospatial measure using zip-code information.
Boys with DMD scored average on total cognition and crystallized cognition scores (n = 55, mean = 90.5, SD = 20.1; n = 56, mean = 103.2, SD = 18.9, respectively). Within the crystallized cognition scores, performance was below age-expected norms in Oral Reading Recognition (Fig. 2B). On fluid cognition, the sons scored lower than age-expected norms (n = 57, mean = 80.1, SD = 17.5). Within the fluid cognition scores, the lowest performance was detected on Flanker and processing speed. Seventeen boys (29%) were from communities of low vulnerability (SVI 1), 15 (26%) from low-to-medium vulnerability (SVI 2), 13 (22%) were from medium-to-high vulnerability (SVI 3), and 13 (22%) (SVI 4) were from high vulnerability. With increasing SVI, sons scored lower on Flanker (r = -0.20).