Confined to wheelchairs and then to bed, with stomach feeding tubes required for nutrient absorption and ventilators to keep their lungs filled with air, stricken children eventually succumb. But MD is a diverse condition. It may not strike until adulthood, and then it can vanish quickly, allowing the patient to live a normal lifespan. Some versions have a fast rate of progression, while others are slow. Some are fatal and kill early, while others allow a long life.
Men are overwhelmingly the victims.
Some other forms of MD can be carried and passed on by either gender and have an even distribution between sexes. This devastating form is responsible for nearly two-thirds of all MD cases. Death almost always occurs before the child leaves his teens. But onset usually occurs later and progresses much more slowly. Patients often live well into middle age.