OBJECTIVES: Duchenne muscular dystrophy (DMD) is a rare, fatal, genetic neuromuscular disease that almost exclusively affects boys and is characterized by progressive muscle weakness. We aimed to develop an epidemiology model for DMD, providing country-specific prevalence estimates of the total diagnosed population and selected subpopulations.

METHODS: To estimate DMD prevalence, country-specific inputs were derived from population statistics and estimates of incidence and survival identified via literature review. Diagnosed incidence rates were applied to number of live male births, then survival curves were used to estimate prevalence of DMD overall, by age group and by ambulatory status. Survival was based on period of birth (pre‑1970, 1970–1990, post‑1990) and accounted for potential differences in median age of death by country. To assess model validity, estimated DMD prevalence was compared with the published prevalence in five studies from the UK, Italy and Japan.

RESULTS: The model provides country‑specific DMD prevalence for nine countries and has the functionality to estimate DMD prevalence in other regions. For the year 2023, the estimated total diagnosed prevalence of DMD is 2055 in the UK, 2082 in France, 2071 in Germany, 1361 in Italy, 1169 in Spain, 1003 in Canada, 5704 in Brazil, 3110 in Japan and 27,931 in China. Age-group distribution was comparable across countries, with approximately an equal partition between paediatric and adult populations. For example, in the UK, patient distribution across age groups 0–3, 4–7, 8–11, 12–17 and ≥18 years was 2%, 14%, 15%, 22% and 47%, respectively. Of the total diagnosed prevalence of DMD, the estimated proportion of ambulatory patients ranged from 31% to 37% across countries. The model‑estimated prevalence showed good alignment with published prevalence, supporting the robustness of the methodology.

CONCLUSIONS: These findings provide robust prevalence estimates that provide greater understanding of the epidemiology of DMD.