Long-term use of steroid treatment is linked to increased weight gain in boys with Duchenne muscular dystrophy (DMD) who are unable to walk, a study shows.
Recognition of the effect of steroid therapy on patients’ weight and growth progression can have important implications on treatment management and early diagnosis of potential complications.
The study, “The effect of steroid treatment on weight in nonambulatory males with Duchenne muscular dystrophy” was published in the American Journal of Medical Genetics.
Steroids have been recommended as a treatment for patients with DMD for decades to preserve or improve muscle strength and motor function, and to prolong independent walking ability by one to three years.
Recent studies have suggested that this therapy also can help prevent or delay the development of spinal deformities, heart and respiratory problems, as well as extend survival.
However, steroid use is still controversial, with researchers and clinicians disagreeing on the optimal dosing regimen used for DMD patients.
An ongoing study, FOR-DMD trial (NCT01603407), is addressing this problem by testing different steroids and steroid dosing regimens on boys with DMD to find which increases muscle strength the most, and which causes the fewest side effects.
To explore long-term effects of steroid use in non-ambulatory DMD patients, researchers reviewed the clinical records of 392 males, from 7 to 29 years old, who were being followed by the Muscular Dystrophy Surveillance, Tracking, and Research Network (MD STARnet).
MDSTARnet is a multi-state research network effort originally funded in 2002 by the Centers for Disease Control and Prevention (CDC). There are surveillance sites in Arizona, Colorado, Iowa, western New York state, South Carolina, and the Utah-Nevada region. Georgia recently joined the network.
A total of 176 patients never had been treated with steroid agents, whereas 216 received Emflaza (deflazacort), prednisolone, or other steroid agent for more than six months. Only seven patients included in the study had started steroid treatment after ambulation loss, while 39% of steroid-treated patients discontinued the treatment about the time they became unable to walk independently.
The data revealed that non-Hispanic white males with DMD were more likely to be treated with steroids than Hispanic or non-Hispanic black DMD males. This difference probably was due to “lower acceptance of the recommended treatment by families, lower rate of steroid treatment offered to minority populations, or lack of culturally sensitive presentation of treatment options,” researchers noted.
Analysis of weight growth curves revealed that steroid treatment is associated with increased weight in non-ambulatory DMD males, often resulting in boys being overweight by the time they reach adolescence.
At younger ages the weight progression curve is similar among both steroid-treated and untreated DMD patients. However, as the non-ambulatory males got older, their weight-for-age fell off compared with the U.S. pediatric male population.
This is likely due to “progressive muscle wasting and replacement with fibrotic tissue,” researchers wrote. “As a male with DMD becomes increasingly disabled due to disease progression, excess weight gain may be a concern for its potential negative effects on health as well as the logistics of caregiving,” they added.
Recognizing this potential side effect of steroids in this population is of major importance in order to make informed decisions about treatment strategy across the lifespan of a DMD patient.
“Males with DMD and their families should be aware of the practical implications of the possible effects on weight, as well as the potential health benefits, when considering postambulatory steroid treatment,” the authors concluded.