Skip to Content

What does DM mean in medical terms?

DM is a common medical abbreviation that can stand for several different medical conditions. The most common meanings of DM in medicine are diabetes mellitus, dermatomyositis, and myotonic dystrophy. Understanding the different definitions of DM can help provide clarity when reading medical notes or reports.

Diabetes Mellitus

One of the most common meanings of DM is diabetes mellitus. Diabetes mellitus refers to a group of metabolic diseases characterized by high blood sugar levels over a prolonged period of time.

There are two main types of diabetes mellitus:

  • Type 1 diabetes – An autoimmune disease where the pancreas stops producing insulin. It often starts in childhood or young adulthood.
  • Type 2 diabetes – The body becomes resistant to insulin or doesn’t make enough insulin. It typically starts later in adulthood.

Common symptoms of diabetes mellitus include:

  • Increased thirst and frequent urination
  • Increased hunger
  • Fatigue
  • Blurred vision
  • Slow healing sores
  • Unintentional weight loss

Diabetes mellitus is diagnosed through blood tests checking glucose levels. It is a chronic condition that requires lifelong management through medications, diet, exercise and blood sugar monitoring.

Prevalence of Diabetes

Diabetes mellitus is a very common condition worldwide. According to the International Diabetes Federation, in 2021 there were approximately:

  • 537 million adults aged 20-79 years worldwide with diabetes. This represents a prevalence of 10.5%.
  • 6.7 million deaths worldwide attributed to diabetes.
  • 374 million adults with impaired glucose tolerance, which puts them at high risk of developing diabetes in the future.

The rates of diabetes have been steadily increasing over the past few decades. This is attributed to factors such as increasing rates of obesity, sedentary lifestyles and greater life expectancy.

Managing Diabetes

While there is no cure for diabetes, it can be effectively managed through:

  • Medications – Such as insulin and oral medications that lower blood glucose levels.
  • Diet – Eating a diet low in simple carbohydrates and high in fiber. Avoiding sugary foods and watching portion sizes.
  • Exercise – Regular physical activity helps lower blood glucose levels and manage weight.
  • Blood sugar monitoring – Checking blood glucose levels regularly and maintaining them within target ranges.

Good management of diabetes can prevent or delay the onset of complications like kidney disease, vision loss, nerve damage, cardiovascular disease and stroke.


Dermatomyositis (DM) is an inflammatory disease that causes muscle weakness and a distinctive skin rash. It is a type of myopathy, which refers to muscle disease.

In dermatomyositis, the immune system mistakenly attacks healthy muscle and skin cells. What triggers this abnormal immune response is unknown.

Some key features of dermatomyositis include:

  • Proximal muscle weakness – Weakness in the muscles closest to the center of the body. This includes muscles of the shoulders, upper arms, hips, thighs and neck.
  • Skin rashes – Red or purple rashes may occur on the eyelids, cheeks, back of the hands, knees, elbows, and chest.
  • Fatigue and joint pain – Patients often experience tiredness, achiness and joint pain.
  • Dysphagia – Difficulty swallowing due to muscle weakness.

In some cases, dermatomyositis can affect internal organ systems like the lungs, heart, and digestive system.

Diagnosis and Treatment

Diagnosis of dermatomyositis involves:

  • Medical history and physical examination
  • Blood tests checking muscle enzymes like creatine kinase
  • Electromyography to assess muscle electrical activity
  • MRI scans to visualize muscle inflammation
  • Biopsy of skin or muscle tissue

Treatment focuses on improving muscle strength and function. Medications used include:

  • Corticosteroids like prednisone to reduce inflammation and immune system activity
  • Immunosuppressant drugs
  • Intravenous immunoglobulin (IVIG)
  • Medications for skin rashes
  • Physical therapy

With treatment, many patients with dermatomyositis see significant improvement in symptoms and muscle strength.

Myotonic Dystrophy

Myotonic dystrophy (DM) is an inherited muscular disorder that affects the muscles and other body systems. It is the most common adult form of muscular dystrophy.

In myotonic dystrophy, the body’s cells have an abnormality in certain genes. This results in increasing inability of the muscles to relax normally (myotonia).

Symptoms of myotonic dystrophy include:

  • Muscle stiffness and prolonged muscle contractions – The muscles have difficulty relaxing after use. Handgrips and handshakes may be prolonged.
  • Muscle weakness and wasting – Usually starts in the face and feet, later affecting the hands, forearms and thighs.
  • Fatigue
  • Slurred speech and swallowing difficulties – Due to weak facial and throat muscles.
  • Cataracts – Cloudiness in the eye’s lens at an earlier than normal age.
  • Cardiac conduction defects – Abnormalities in the electrical signals that coordinate heart contractions.
  • Excessive daytime sleepiness
  • Cognitive impairment – About 40% of people affected have some degree of intellectual disability.

Myotonic dystrophy is a slowly progressing condition. The severity and age of onset varies between patients, even within the same family.

Diagnosis and Treatment

Myotonic dystrophy is diagnosed through:

  • Genetic testing – To look for the abnormality in the DMPK gene on chromosome 19.
  • Electromyography – Records the electrical signals of muscle activity.
  • Muscle biopsy

There is currently no cure for myotonic dystrophy. Treatment focuses on managing symptoms through:

  • Physical therapy – Stretching and strength training exercises
  • Speech therapy
  • Assistive devices – Such as ankle-foot orthoses, canes, wheelchairs
  • Medications – Such as anti-arrhythmic drugs for heart problems, stimulants for sleepiness
  • Surgery – Such as cataract removal or pacemaker placement if needed

Care is aimed at maximizing quality of life and independence. Genetic counseling may help families understand risks for inheriting the condition.


DM is an abbreviation that can stand for several different medical conditions – most commonly diabetes mellitus, dermatomyositis and myotonic dystrophy. Diabetes mellitus is a very prevalent metabolic disorder affecting glucose regulation. Dermatomyositis is an inflammatory disease causing muscle weakness and rashes. Myotonic dystrophy is a genetic muscular disorder that progressively worsens muscle function.

Being familiar with the different meanings of DM helps provide clarity when reading through medical records or communicating with health professionals. This allows quicker recognition of which specific medical condition is being referenced.

The context in which DM is used will make it clear which specific meaning is intended. For example, if DM is mentioned along with terms like glucose, insulin and HbA1c – it is referring to diabetes mellitus. If it is discussed along with weakness, IVIG and creatine kinase – it indicates dermatomyositis. And if DM is described together with myotonia, muscular dystrophy and cataracts – it points to myotonic dystrophy.

Having a good understanding of medical terminology like DM leads to improved communication and better patient care.