Delays in diagnosis of Duchenne muscular dystrophy: An evaluation of genotypic and sociodemographic factors

Introduction: In this study we investigate associations between genotypic and sociodemographic factors and the age of diagnosis of Duchenne muscular dystrophy (DMD). Methods: Data were collected from the Duchenne Registry from 2007 to 2019, and then used to assess the impact genotype, race/ethnicity, neighborhood poverty levels, and other sociodemographics factors have on the age of diagnosis of DMD patients without a known family history, using univariate and multivariable linear regression. Results: The mean age of diagnosis was 4.43 years. Non-Caucasian patients and patients from high-poverty neighborhoods were older at diagnosis (P < .01). Increased year of birth was associated with decreasing age of diagnosis (P < .001). Specific genetic mutation subtypes were associated with later ages of symptom onset and diagnosis (P = .005). Discussion: After adjusting for genotype and year of birth, the average age of diagnosis was significantly later for traditionally at-risk patients.