Analysis of mortality in a cohort of adult Duchenne muscular dystrophy

source: Neuromuscular Disorders

year: 2017

authors: L. Nastase, M. Desikan, S. Price, F. Crummy, J. Kahn, R. Quinlivan

Duchenne muscular dystrophy (DMD) survival has substantially improved in recent years with mean life expectancy at 29 years and a growing number surviving into fourth and fifth decades. However, despite this, premature deaths still occur and the most common reported cause is cardiomyopathy. The aim of this retrospective data collection study was to gain a better understanding of premature mortality in DMD and identify potential avoidable risk factors. We reviewed causes of death in a cohort of 83 adults with DMD followed up at our centre (mean age 22.5 ± 3.6), and analyzed the events leading to these deaths. Fourteen deaths were registered between 2012 and 2017. These deaths can be regarded as unexpected, if we consider the young age at death (mean 21.1 ± 2.5) and mean age at loss of ambulation 11.4 ± 1.9. Eleven patients (79%) were steroid naïve or had discontinued steroid treatment in childhood. Interestingly, 8/14 patients (57%) had autism or learning disability (LD). The cause of death was due to cardiomyopathy in 6 (42%) and respiratory failure in 3 (21%, all of whom had autism/LD and were non-compliant with NIV). One died from tracheostomy haemorrhage. One died from pseudo-obstruction but was also non-compliant with NIV and had LD/autism. Three (21%) died from cachexia of which two had LD/autism. These findings are in keeping with the current medical literature on mortality in DMD, but the frequency of autism/LD in our sample of patients who died prematurely was greater than would be expected for the DMD population, suggesting that this group of patients is at greater risk of premature death. Beginning a the process to familiarize these patients with NIV in the paediatric setting and considering PEG insertion at an earlier stage may help to improve outcome in this group. Multi-centre, prospective surveillance of mortality may help to clarify these data further.