Objective: To describe the effect of glucocorticoid treatment on age at wheelchair dependence and at dependence on part-time (<23 hrs/day) and continuous noninvasive mechanical ventilation.
Design: In this retrospective study, patients with Duchenne muscular dystrophy who received glucocorticoid therapy were compared with those who did not for ages at wheelchair dependence and when beginning part-time (nocturnal) and continuous noninvasive intermittent positive pressure ventilation (NIV). Respiratory symptoms, end-tidal carbon dioxide, oximetry, and vital capacity were noted every 4-12 mos, and NIV was initiated for symptomatic nocturnal hypoventilation. The daily NIV use increased until some required it continuously to survive.
Results: The 117 untreated patients became wheelchair-dependent at 9.7 +/- 1.3 yrs of age. Four then died from cardiac failure, and five were older than 19 yrs without using NIV. The remaining 108 began nocturnal NIV at 19.2 +/- 3.7 yrs of age. Ninety of the 108 became continuously NIV-dependent at 21.9 +/- 4.5 yrs of age, and the 17 treated with glucocorticoid therapy became wheelchair-dependent significantly later at 10.8 +/- 1.3 yrs of age (P = 0.02). Three died from cardiac failure, and three were older than 19 yrs without using NIV. The remaining 11 began nocturnal NIV at 22.9 +/- 5.3 yrs of age (P = 0.05). Eight of the 11 became continuously NIV-dependent at age 28.9 +/- 7.3 yrs (P = 0.005).
Conclusions: Intermittent glucocorticoid therapy delays wheelchair dependence and may delay ventilator dependence for patients with Duchenne muscular dystrophy.