P.7.8 The national Dutch dystrophinopathy patient registry

Dystrophinopathy patient registries are very useful for improvement of standard care and planning of clinical trials. The Dutch Dystrophinopathy Database contains information of Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) patients in the Netherlands. The historical incidence of DMD is estimated at 20 boys per year and unknown for BMD. DMD and BMD patients received information through patient organisations, treating physicians, the genetic test centre or a website ( www.lumc.nl/duchenne ). Included patients gave consent for registration in the national patient registry and the international TREAT-NMD database, permission to contact their physician and filled out a questionnaire about their disease course. On January 2013 the database contained disease milestones of 420 DMD and 140 BMD patients, including data from 78 deceased DMD and 16 deceased BMD males. 324 DMD and 104 BMD patients have a DNA confirmed diagnosis. The mean yearly incidence for DMD was 18 between 1980 and 2000. Given a mean life expectancy of 27 years this would suggest a prevalence of 486 DMD patients, and thus an inclusion rate in the database of 70%. The mean yearly incidence for BMD was 4 between 1960 and 2000. The mean life expectancy was 55 years suggesting a prevalence of 220 BMD patients, and thus an inclusion rate in the database of 56%. In the DNA confirmed DMD cohort mean age at diagnosis decreased from 5.6 years before 1970 to 4.0 years more recently. The mean age at loss of ambulation increased to 9.8 years and for scoliosis surgery to 14 years. Age at start of mechanical ventilation ranged from 14 to 28 years. Close collaboration during five years between patient organisations, physicians and researchers resulted in a patient registry covering three quarters of all Dutch DMD patients. The yearly update is a constant challenge, but the advantage is one national registry representative for the whole population, limiting selection bias to a minimum.