Inclusion body myositis (IBM) is a rare inflammatory muscle disease characterised by progressive muscle weakness and wasting.
What is Inclusion Body Myositis?
Inclusion body myositis (IBM) is an idiopathic inflammatory myopathy that primarily affects adults over the age of 50. Unlike other myopathies, IBM is both an inflammatory and degenerative disease. It involves chronic inflammation of the muscles alongside the presence of abnormal protein deposits, known as inclusion bodies, within the muscle fibres. This dual pathology makes IBM particularly challenging to treat.
Symptoms of Inclusion Body Myositis
The symptoms of IBM develop gradually, often over several years, and typically include:
Muscle Weakness
- Distal Muscle Weakness – Weakness in the muscles farthest from the center of the body, such as the hands and feet. Commonly affected areas include the finger flexors and foot extensors, leading to difficulties in gripping and foot drop.
- Proximal Muscle Weakness – Weakness in muscles closer to the trunk, such as the quadriceps and hip flexors. This can cause difficulties in rising from a seated position, climbing stairs, and walking.
Muscle Atrophy
- Wasting – Noticeable thinning and wasting of affected muscles over time.
Swallowing Difficulties
- Dysphagia – Difficulty swallowing due to weakness of the throat muscles, which can lead to choking or aspiration.
Balance and Coordination Issues
- Frequent Falls – Due to muscle weakness and atrophy, individuals with IBM may experience balance issues, increasing the risk of falls and injuries.
Fatigue
- Persistent Tiredness – Generalized fatigue and lack of energy, often accompanying muscle weakness.
Causes and Risk Factors
The exact cause of IBM is not well understood, but it is believed to result from a combination of genetic, immune system, and possibly environmental factors:
- Genetic Susceptibility – While IBM is generally not inherited in a straightforward manner, certain genetic markers may increase the risk of developing the disease.
- Autoimmunity – The immune system mistakenly attacks muscle tissue, leading to chronic inflammation and damage.
- Unknown Triggers – While no specific environmental triggers have been conclusively identified, some researchers speculate that infections or other external factors might contribute to the disease process.
Diagnosis
Diagnosing IBM involves a thorough evaluation by a healthcare professional, including:
- Symptom Inquiry – Your doctor will ask about your symptoms, their onset, progression, and any family history of muscle diseases or autoimmune disorders.
- Muscle Assessment – Examining the affected muscles for signs of weakness, atrophy, and inflammation.
- Blood Tests – To measure levels of muscle enzymes (e.g., creatine kinase), which are often elevated in muscle inflammation, and to check for specific autoantibodies.
- Muscle Activity – Measures the electrical activity of muscles to identify abnormalities indicative of myopathy.
- Tissue Sample – A small sample of muscle tissue is taken to look for characteristic features of IBM, including inflammatory cells, muscle fibre degeneration, and inclusion bodies.
- MRI – To assess muscle inflammation and damage and to help differentiate IBM from other myopathies.
Treatment Options
There is currently no cure for IBM, and treatment focuses on managing symptoms and improving quality of life. Treatment options may include:
Medications
- Anti-inflammatory Drugs – Although corticosteroids and immunosuppressive drugs are commonly used to treat other inflammatory myopathies, they are generally not effective in IBM.
- Experimental Therapies – Research is ongoing to find more effective treatments, and some patients may have the opportunity to participate in clinical trials.
Physical Therapy
- Exercise Programs – Tailored exercises to maintain and improve muscle strength, flexibility, and function. Physical therapists can design safe and effective exercise regimens for individuals with IBM.
- Occupational Therapy – Techniques to assist with daily activities, improve hand function, and maintain independence.
Supportive Devices
- Mobility Aids – Using canes, walkers, or wheelchairs to aid mobility and prevent falls.
- Braces and Splints – To support weak muscles, improve stability, and reduce the risk of injury.
Nutritional Support
- Dietary Modifications – Adjusting diet to address swallowing difficulties and ensure adequate nutrition. Speech and language therapists can provide strategies for managing dysphagia.
Managing and Living with Inclusion Body Myositis
Living with IBM involves a combination of medical treatment, lifestyle changes, and self-care strategies. Here are some tips:
- Take any prescribed medications as directed by your doctor to manage symptoms and participate in clinical trials if applicable.
- Engage in regular, low-impact exercises such as swimming, walking, or cycling to maintain muscle strength and overall health while avoiding overexertion.
- Eating a balanced diet rich in fruits, vegetables, whole grains, and lean proteins to support overall health. Special dietary considerations may be necessary to manage swallowing difficulties.
- Implement safety measures at home, such as using non-slip mats, installing grab bars, and ensuring good lighting to reduce the risk of falls and injuries.
- Joining support groups or talking to a counsellor can help manage the emotional challenges of living with a chronic disease.
- Regularly visit your healthcare provider to monitor disease progression, adjust treatment as needed, and address any new symptoms or concerns.
Inclusion body myositis is a rare and challenging autoimmune muscle disease that primarily affects older adults. While there is currently no cure, with early diagnosis and appropriate management, individuals with IBM can maintain a good quality of life.
