Glucocorticoids Reduce Comorbidity Frequency in Adults With DMD, Study Finds

A study published in Neuromuscular Disorders found that treatment with glucocorticoids reduced comorbidity frequency in adults with Duchenne muscular dystrophy (DMD) and that certain anthropometric measures were associated with respiratory function and functional abilities.¹

In patients with DMD, a fatal genetic condition characterized by progressive muscle atrophy, glucocorticoid treatment is widely used and can even continue to benefit patients following loss of ambulation.² Standards of care such as glucocorticoid treatment and multidisciplinary disease management have extended life expectancy for patients with DMD, but adults with the condition often develop comorbidities due to progressive muscle impairment and long-term glucocorticoid use.¹

“The beneficial effect of continuing glucocorticoids after loss of ambulation on motor, respiratory and cardiac function in DMD has been described,” the study authors noted, “however, their effect on these comorbidities in adulthood remains to be explored.”

Doctor holding tablet reading Duchenne muscular dystrophy | Image credit: luchschenF - stock.adobe.com

While motor, cardiac, and respiratory function are consistently monitored in patients with DMD, comorbidities associated with the disease may not be routinely discussed at clinical appointments, and they may be underreported by patients. The authors also noted a study that found delayed gastrointestinal transit time did not correlate with patient-reported gastrointestinal symptoms, which demonstrated a need to closely monitor even asymptomatic patients and to identify clinical features associated with comorbidities to improve detection and treatment. 

The single-center cross-sectional study explored the frequency of disease-associated comorbidities and their associated factors, medication prescription frequency, and the association between anthropometric measures and functional abilities and respiratory function among adults with DMD.

A total of 112 adults were included in the study, with a mean age of 23.4 years at last assessment. All patients were genetically diagnosed with DMD, and 66.07% (n = 74) were on glucocorticoids after loss of ambulation, while the rest were glucocorticoid naive. Both univariate and multivariate analyses were done to identify factors correlated with dysphagia, constipation, body mass index (BMI), and weight. Associations between BMI, weight, and respiratory and motor abilities were done with regression analysis.

Regarding comorbidity frequency, 61.6% of patients (n = 69) had scoliosis, with 61.0% of those individuals (n = 42) having spinal surgery. Glucocorticoid use was found to delay time to spinal surgery. Additionally, 36.6% of patients had dysphagia, 36.6% had constipation, and 27.8% had urinary conditions.

In a univariate analysis, dysphagia and constipation were associated with age, glucocorticoid naivety, and lower respiratory and motor function. Multivariate analysis found that impaired cough ability was consistently linked with both dysphagia and constipation. Lower BMI and weight were associated with constipation, and while BMI and weight showed a positive correlation with respiratory measures, they were not associated with functional abilities.

The researchers also found that all but 1 individual were taking 1 or more medications aside from glucocorticoids, with 5 (IQR, 4-6) being the median number of medications per patient. Overall, 61.71% of patients (n = 68) were taking 5 or more medications, and the number of medications did not differ based on glucocorticoid status. Angiotensin-converting enzyme inhibitors or angiotensin II receptor antagonists, β-blockers, and vitamin D were the most common medications (90.17%, 85.71%, and 62.5% of patients, respectively).

Study limitations included its retrospective nature, which led to missing data, as well as an extended observation period that included changing standards of care over time. The long observation period could also have included a shift to more proactive care and impacted the reporting of comorbidities, the authors noted. Patient-reported symptoms and clinician reporting were also used to gauge comorbidity frequency vs systematic formal screening tools. Most individuals took glucocorticoids daily, so intermittent regimens could not be investigated, and some patients (n = 10) stopped glucocorticoid treatment prior to loss of ambulation and started again after ambulation loss and therefore could not be analyzed in distinct groups.

“In conclusion, glucocorticoids decrease the frequency of dysphagia, constipation, and spinal surgery in adults with DMD,” the authors wrote. “A weak cough is linked with dysphagia and constipation, serving as a valuable clinical indicator for assessing susceptibility to these comorbidities. The BMI and weight can influence the respiratory performance in adults with DMD.”

References

1. Schiava M, Lofra RM, Bourke JP, et al. Disease-associated comorbidities, medication records and anthropometric measures in adults with Duchenne muscular dystrophy. Neuromuscul Disord. Published online May 14, 2024. doi:10.1016/j.nmd.2024.05.007

2. McNulty R. Glucocorticoids preserve late-stage functional abilities in DMD after loss of ambulation, study finds. AJMC. April 12, 2024. Accessed May 23, 2024. https://www.ajmc.com/view/glucocorticoids-preserve-late-stage-functional-abilities-in-dmd-after-loss-of-ambulation-study-finds