The median estimated age of death in patients with Duchenne muscular dystrophy (DMD) is just under 24 years, with elevated mortality rates in non-Hispanic Black patients compared to non-Hispanic White patients, according to a study recently published in Neuromuscular Disorders.
Since 2004, the study has analyzed and longitudinally followed 526 male patients born between 1982 and 1999 with a diagnosis of DMD in the United States, to estimate the median age of death using the Muscular Dystrophy Surveillance, Tracking, and Research Network (MD STARnet) methodology.
The study also evaluated the relationship between all-cause mortality and race, cough assist machines, glucocorticoids, scoliosis surgery, cardiac medications, and bilevel positive airway pressure (BiPAP) in patients with DMD.
The authors observed that patients who used glucocorticoids had lower hazard mortality compared to patients who did not use glucocorticoids. In fact, after ambulation loss, patients who used glucocorticoids or cough assist machines or had undergone scoliosis surgery had prolonged survival rates, results comparable with the 2018 Care Considerations. Moreover, no clear associations were found between all-cause mortality and the use of cardiac medications or BiPAP.
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“We observed that in any given year starting at age 10 years, controlling for other factors, individuals who were currently using glucocorticoids were 83% less likely to die than individuals who were not currently using glucocorticoids,” the authors wrote. “Similarly, in any given year after loss of ambulation, individuals who were currently using glucocorticoids were 77% less likely to die.”
Regarding the difference in mortality between non-Hispanic White patients and non-Hispanic Black patients, the authors pointed out that it may be due to several inconsistencies in care, such as the fact that Black patients use less overall health care, primary care, and outpatients services compared with White patients, according to previous studies. Additionally, Black patients have both elevated emergency department usage as well as hospitalizations, compared with White patients.
Another factor in the mortality difference between the groups may be unmeasured clinical and social determinants of health.
There is no established cure for DMD, but several treatments and interventions work on slowing the progression of the disease and delaying the development of comorbidities. Understanding the survival rates and how these treatments and interventions may affect these estimates could help improve the care of patients with DMD.
Paramsothy P, Wang Y, Cai B et al. Selected clinical and demographic factors and all-cause mortality among individuals with Duchenne muscular dystrophy in the Muscular Dystrophy Surveillance, Tracking, and Research Network. Neuromuscul Disord. Published online April 30, 2022. doi:10.1016/j.nmd.2022.04.008