How Myotonic Dystrophy Affects Your Body

Myotonic dystrophy (DM) can affect all age groups, and people living with DM often have different symptoms at different ranges of severity. DM can also affect a range of systems, so symptom management requires a more expansive approach. You’ll likely need to coordinate with a multidisciplinary team to provide comprehensive care. Here’s an article that shows the range of specialists you might work with, and what they’re focus will be.

Click on the arrows by each body system below to expand descriptions. For Medical Professionals: Each "Deep Dive" section includes specific clinical care recommendations.

Cardiovascular System

  • Heart rhythm problems (arrhythmias)
  • Enlarged heart muscle
  • Low blood pressure
  • Sudden death


  • Difficulty with thinking and problem solving
  • Emotional and behavior problems
  • Excessive daytime sleepiness
  • Nerve damage in feet and hands

Reproductive System

  • Small testes, low sperm count, low testosterone
  • Higher risk of miscarriage and stillbirth; early menopause
  • Problems with pregnancy and delivery
  • Newborn complications


  • Cataracts
  • Damage to the retina
  • Drooping eyelids (ptosis)



Immune System

  • Lower levels of antibodies in bloodstream (hypogammaglobulinemia)
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  • Higher risk of benign skin tumor (pilomatrixoma)
  • Alopecia
  • Dysplastic nevi
  • Seborrheic dermatitis

Respiratory System

  • Breathing problems in newborns
  • Frequent lung infections
  • Aspiration of food or fluids into airways
  • Inability to breathe in enough oxygen
  • Sleep apnea

Gastrointestinal System

  • Difficulty swallowing
  • Pain and bloating after meals
  • Constipation, diarrhea, irritable bowel syndrome, gastrointestinal reflux
  • Gallstones
  • Enlarged colon


  • Insulin resistance
  • Premature frontal balding in men


  • Muscle weakness (myopathy)
  • Muscle stiffness and trouble relaxing a muscle (myotonia)
  • Muscle wasting that gets worse over time (atrophy)
  • Severe muscle weakness and delayed development in newborns and infants


  • Inherited disease, autosomal-dominant mutation
  • 50% chance of passing mutated gene to each child
  • More severe with each generation ("anticipation")

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