Prevalence of Duchenne muscular dystrophy in Italy: a nationwide survey

Purpose The availability of care recommendations has improved survival and delayed the progression of clinical signs in Duchenne muscular dystrophy. The aim of the study was to perform a nationwide survey investigating the prevalence, age distribution, and functional status of Duchenne muscular dystrophyin Italy. Methods The survey was performed by collecting data from all 31 reference centers for Duchenne muscular dystrophy in Italy using a structured form. We assessed age distribution, motor function, and the need for respiratory and nutritional support to evaluate their prevalence in different age and functional subgroups. Results The estimated prevalence was 1.65/100,000 (3.4/100,000 males). There were 972 boys and adults with a confirmed diagnosis of Duchenne, of age ranging between 6 months and 48 years (mean = 16.5). Over 59% were below the age of 18 years and the remaining 41% were adults. Over 43% were ambulant and 57% non-ambulant; 14.7% were steroids naive (mean 20.6 years), 75% are currently on steroids (mean 14.6 years) with 604 on the daily regime, 126 intermittent. Nearly 73% did not require any ventilatory support, 16% had NIV <= 12 h, 9% > 12 h, and 1.4% had a tracheostomy. More than 82% did not require any nutritional support, 13% required food modification/semisolid and 4.4% had a G-tube. Conclusions: Our findings provide information to be used not only for epidemiological purposes but also for possible trial design to include older non-ambulant patients who until recently have been excluded and for whom clinical information is limited.