A longitudinal study published in December 2022 compared disease progression after the loss of walking in 86 boys with DMD with or without steroid therapy (prednisone or deflazacort). Participants aged 3-18 years had lost their ability to walk either before or during the study. Muscle, lung and heart function were assessed every six months for three years:
- Treatment with deflazacort or prednisone slowed the decline in predicted forced vital capacity in participants (+3.23 points and +3.73 points per year, respectively), although the difference was significant only for deflazacort.
- At the cardiac level, the left ventricular ejection fraction measured throughout the study decreased more slowly in the treated groups compared to the control group (prednisone and deflazacort: +2.67 units/year).
- Participants treated with deflazacort had a slower decline in PUL scores compared to the control group (+4.0 points/year) but also to the prednisone group (+1.5 points/year).
- At the age of 15 years, 85% of the participants treated with deflazacort retained the gesture of putting the hand to the mouth compared to 83% of the prednisone group and 78% of the control group.
- The ability to eat alone and without arm support was lost significantly later in participants treated with deflazacort (+2.6 years than the prednisone group and +2.3 years than the control group).
- The ability to roll over independently in bed was significantly better preserved in the deflazacort group (+6 years than the prednisone group and +4.6 years than the control group).
- Treated patients experienced less severe weight loss than the control group.
