Duchenne Muscular Dystrophy (DMD) is an X-linked recessive neuromuscular disease. This fatal disease affects approximately 1:3,500 to 6,000 live male births [1] and 1:50,000,000 live female births [2], [3].
That's because the gene responsible for the protein dystrophin — where the mutation occurs — is located on the X chromosome, one of the two sex chromosomes in humans. Females have two X chromosomes, while males have one X and one Y chromosome.
The average lifespan for Duchenne muscular dystrophy is 18 to 25 years. With early treatment, it can reach 30 years. But recent technological advances have made it possible to improve treatment.
Most carrier females (about 80-90%) have no problems with their skeletal muscles. Some have mild muscle weakness, fatigue (a tired feeling), or cramping in their muscles. Rarely, a carrier has symptoms that are as severe as those of a male with muscular dystrophy.
Female carriers of DMD mutations do not usually have symptoms. Symptoms vary, but may include muscle pain and cramps with physical exertion, severe muscle weakness and dilatation of the heart.
This special MDA report takes a look at the issues that arise for expectant mothers with muscle disease and finds that, with proper care and planning, these women are usually — although not always — able to have successful pregnancies and give birth to healthy children.
Duchenne muscular dystrophy is the most common type of muscular dystrophy. The life expectancy for this type is around the ages of 16 to the early 20s. Becker muscular dystrophy has a higher life expectancy, usually into the 30s or 40s.
In group 2, fat embolism, cardiac arrhythmia and adrenal insufficiency were also potential contributing factors. Conclusions: The main cause of death in DMD in our population remains cardio-respiratory failure. Four patients (19%) died in their teenage years in the absence of severe cardiorespiratory failure.
Polymyositis is sometimes mistaken for muscular dystrophy, so careful diagnosis is important. Some of the tests for polymyositis include: Medical history – people with other connective tissue diseases, such as scleroderma, are at greater risk of polymyositis.
Approximately 70% (2 out of 3) of children born with Duchenne have inherited the genetic mutation from their mother who is a carrier. However, approximately 30% (1 out of 3) of children born with Duchenne have a genetic change that started new in them and was not inherited from their mother.
The muscular dystrophies (MD) are a group of inherited genetic conditions that gradually cause the muscles to weaken, leading to an increasing level of disability. MD is a progressive condition, which means it gets worse over time.
Most carrier females (about 80-90%) have no problems with their skeletal muscles. Some have mild muscle weakness, fatigue (a tired feeling), pain or cramping in their muscles. Rarely, a carrier has symptoms that are as severe as those of a male with muscular dystrophy.
Muscular dystrophy occurs in both sexes and in all ages and races. However, the most common variety, Duchenne, usually occurs in young boys. People with a family history of muscular dystrophy are at higher risk of developing the disease or passing it on to their children.
Until recently, children with Duchenne muscular dystrophy (DMD) did not often live beyond their teens. However, improvements in cardiac and respiratory care mean that life expectancy is increasing, with many DMD patients reaching their 30s, and some living into their 40s and 50s.
It is common knowledge that oculopharyngeal muscular dystrophy (OPMD) is a late-onset disease, since the age at onset is always beyond 50 years, whereas late-onset Pompe disease starts at age 12 months since this subtype is distinguished from the infantile onset Pompe disease.
Signs of the late ambulatory stage appear during the late childhood or adolescence. As the disease progresses, muscle weakness and wasting (atrophy) start to affect the lower legs, forearms, neck, and trunk.
CMDs are a group of disorders that involve more than only muscles; other body structures including the brain, eyes, and heart may be affected.
We also asked people about where they experience pain most frequently. People responded that they most frequently felt pain in the lower back and legs. Back pain was reported in 66% of people with MMD and 74% of people with FSHD. Leg pain was reported in 60% of people with MMD and 72% of people with FSHD.
Life expectancy for muscular dystrophy depends on the type. Some children with severe muscular dystrophy may die in infancy or childhood, while adults who have forms that progress slowly can live a normal lifespan.
In most cases, muscular dystrophy (MD) runs in families. It usually develops after inheriting a faulty gene from one or both parents. MD is caused by mutations (alterations) in the genes responsible for healthy muscle structure and function.
Once the new mutation has been passed to a son or daughter, he or she can pass it to the next generation. A man with BMD can't pass the flawed gene to his sons because he gives a son a Y chromosome, not an X. But he'll certainly pass it to his daughters, because each daughter inherits her father's only X chromosome.