Change in respiratory outcomes in adults with Duchenne muscular dystrophy in the era of corticosteroids.

OBJECTIVE

In patients with Duchenne muscular dystrophy (DMD) the effect of continued corticosteroid (CS) use into adulthood on respiratory function remains unclear. We studied if prolongation of CS into adulthood is beneficial for forced vital capacity (FVC), age at start of non-invasive ventilation (NIV), and age at start of continuous (24/24 h) ventilation.

METHODS

In this retrospective study, adult (≥18 years) DMD patients were stratified into 20 'CS-naïve' patients (never used CS or only as a child during <1 year) and 37 'continued CS' patients (continued CS until age of 18 years or older).

RESULTS

'Continued CS' patients showed at 18 years a higher FVC%pred (50.3, SD:16.4) compared to 'CS-naïve' patients (36.9, SD:13.8) (p = 0.007). Patients continuing CS beyond the age of 18 demonstrated a slower annual decline in FVC%pred of 2.9% (SE:0.5) in comparison to 3.8% (SE:0.4) in the 'CS-naïve' group, and the difference in relative annual decline in FVC%pred was significant (p = 0.012). The annual decline in FVC in absolute value in patients continuing CS was 102 ml (SE:28) slower in comparison to 'CS-naïve' patients (p < 0.001). Moreover, there was a delay in age at initiation of NIV: mean age at start of NIV was 28.3 (95%CI: 25.4-31.2) in 'continued CS' in comparison to 20.3 (95%CI: 19.0-21.6) in 'CS-naïve' patients (p < 0.001), and at start of continuous NIV 33.3 (95%CI: 31.5-35.2) in comparison to 26.0 (95%CI: 24.7-27.2) years (p < 0.001).

CONCLUSION

Our data suggest benefit of continuing CS until age 18 years and beyond on respiratory function including delayed need to start (continuous) NIV.