Management of Polymyositis in Older People

What Is Polymyositis?

Polymyositis is an autoimmune disorder (the body's defense mechanism works against itself) that presents with swelling, tenderness, and weakening of the body's muscles. It is one of the subtypes of a large group of muscle disorders called myopathies. Polymyositis usually occurs due to abnormal activity of the cytotoxic T- lymphocytes cells and macrophages, which in turn causes muscle damage by acting against the muscle antigen. Polymyositis is a slowly progressing condition and occurs in older age groups. The symptoms can vary from mild to severe. The diagnostic sign of polymyositis involves mostly the truncal muscles (the neck and shoulder muscles). In a few people, hip muscles are involved, which disturbs the patient's gait and results in difficulty walking. In addition, changes in posture are observed in such patients. Patients may need a cane or wheelchair sometimes in cases of an acute flare-up of polymyositis disorder. Polymyositis mostly affects the skeletal muscles.

What Is the Prevalence of Polymyositis?

• Polymyositis can occur in people of any age. However, it most commonly affects older people in the age group of fifty to sixty years old.

• Females are more likely to be affected by polymyositis as compared to males.

What Causes Polymyositis?

Experts are unsure of the cause of polymyositis, an autoimmune illness. When the immune system unintentionally attacks the body rather than protecting it, autoimmune disorders result. Polymyositis may occur spontaneously (idiopathic) with no known etiology. Occasionally, it is brought on by drug responses or other medical issues.

The following autoimmune conditions increase a person's risk of developing polymyositis:

• Lupus Disease: An inflammatory illness brought on by tissue attacks by the immune system. The brain, heart, lungs, blood cells, joints, skin, kidneys, and heart can all be impacted by lupus (SLE).

• Rheumatoid Arthritis: A long-term inflammatory condition that affects numerous joints, especially the hands and feet.

• Scleroderma: Persistent stiffening and hardening of the connective tissues and skin.

Polymyositis can be brought on by some viral infections, including:

• COVID-19.

• Common cold.

• HIV - HIV impairs the body's defenses against infections and is the cause of AIDS.

What Are the Risk Factors for Polymyositis?

Although polymyositis can affect everyone, certain individuals are more susceptible than others, such as:

• Individuals marked as female at birth (AFAB). Those assigned male at birth (AMAB) have a one in two chance of developing polymyositis.

• Those who suffer from other autoimmune conditions.

• Those in their 30s to 60s. Although it can appear at any age, adults in this range will likely have it.

What Are the Signs and Symptoms of Polymyositis?

Signs and symptoms associated with polymyositis are:

• Muscular weakness.

• Muscle and joint pain.

• Difficulty in swallowing.

• Fever.

• Weight loss.

• Rashes around the eyes.

• Difficulty with climbing stairs, getting up from chairs, and lifting objects.

• Loss of appetite.

How Is Polymyositis Diagnosed?

A medical professional uses a physical examination and some tests to diagnose polymyositis. They will assess the weak muscles and inquire about the symptoms. The doctor will diagnose polymyositis using a few different tests. Certain tests are designed to rule out other medical disorders that may present with similar symptoms. The supplier may employ:

• Blood Tests: Check for antibodies or muscle enzymes that indicate your muscles are damaged.

• Electromyography: EMG is a technique to determine whether your muscles' electrical impulse patterns are normal.

• MRIs: Magnetic resonance imaging (MRI) is a technique that scans and creates images of immense sections of your muscle.

• Muscle Biopsy: To determine whether the muscle tissue is inflamed, your doctor will remove a tiny sample of your muscle for examination.

How Is Polymyositis Managed in Older People?

The management of polymyositis in older people depends on each individual. Therefore, it should be managed by a multispecialty team. A thorough clinical examination and diagnosis should be performed using different diagnostic tests such as electromyographic examination, biopsy, chest X-ray, mammograms, and other screening tests to rule out polymyositis. Different techniques for the management of polymyositis symptoms in adults are:

1. Pharmacological Management:

• Corticosteroids: Steroid drugs such as Prednisone or Methylprednisolone have proven efficacy in the management of symptoms of polymyositis. Prednisone is usually prescribed at the dosage of 1 milligram per kilogram each day. The only drawback with corticosteroids is that continuous or long-term drug use can lead to various adverse effects. Therefore, tapering the drug dose is needed to reduce or stop the drug. Corticosteroids reduce the swelling of joint muscles and also suppress immune system response by reducing or restricting antigen production, early production of B and T cells, and proliferation of B and T cells.

• Corticosteroid-Sparing Agents: When combined with corticosteroids, immune modulatory drugs reduce or suppress the adverse effects caused by steroids. Azathioprine and Methotrexate are the most commonly used agents that help manage the symptoms of polymyositis by restricting the proliferation of B and T lymphocyte cells. Other medications that are used are Cyclosporine and Tacrolimus. Corticosteroid-sparing agents are mostly recommended for patients who either do not respond to the corticosteroid therapy or are showing various adverse effects due to the long-term use of corticosteroids.

• Biological Drugs: Medications like Rituzumab can be used if other initial medicines fail to resolve the symptoms and flare-ups of polymyositis.

2. Non-Pharmacological Management:

• Physiotherapy: Physical therapy of the affected muscles is also important to prevent muscular atrophy. Patients with polymyositis are referred to physiotherapists for strength training exercises or activities such as range-of-motion exercises (placing the joints in the normal range of movement) under the supervision of trained therapists. These exercises help the patient keep their joints supple or flexible.

• Nutritionist: Nutrition and diet also play an important role in muscle building. A proper diet comprising protein-rich foods is recommended for patients with polymyositis, as it helps build muscle and strengthens muscles. Patients are referred to a certified nutritionist or dietician for a proper diet plan, as patients with polymyositis usually have difficulty swallowing and chewing, making their nutrition compromised.

• Speech Therapy: Speech or vocal therapies are recommended for patients who present with the weakening of the muscles of deglutition (swallowing muscles) or vocal cord muscles. Patients are referred to speech and language therapists to manage the symptoms.

3. Other Treatment Modalities:

• Intravenous Immunoglobulins (IVIG): In a few patients with refractory polymyositis, intravenous (into the vein) immunoglobulins (antibodies culled from donors) can effectively manage symptoms associated with severe forms of polymyositis, such as dysphagia (difficulty swallowing).

• Plasmapheresis: Plasmapheresis (cleansing of blood) is the oldest technique and is rarely used nowadays to manage myositis. This technique removes the antibodies and proteins produced by the immune system in the patient's blood and then reverts the cleanse and filtered blood back to the patient's body.

What Is the Prognosis of Polymyositis?

Around one in five patients usually dies of polymyositis within five years of the disease. Death due to polymyositis in older people occurs due to the following:

• Respiratory failure.

• Pneumonia.

• Malnutrition.

• Chronic muscle weakness.

The severity of your polymyositis disease determines your prognosis. Most patients react to treatment and regain some of their muscle strength. You might still feel some weakness, and your symptoms can return. Even though the illness is rarely fatal, if you do not receive the right care, you run the risk of being crippled.

What Is the Current Research Ongoing for the Treatment of Polymyositis in Older People?

• Although there is no complete cure for polymyositis, symptomatic management of the disease flare-ups can be done using combined treatment modalities.

• Various clinical trials are ongoing to understand how the immune cell acts against its muscle tissue, resulting in muscular damage in polymyositis. Understanding the basic mechanism may help researchers develop better treatment modalities for the complete and permanent cure of patients with polymyositis.

Conclusion

Polymyositis is an autoimmune disease mostly encountered in the late elderly stage. Early diagnosis by clinical and endoscopic examination of the patient should be made thoroughly for the definitive management of polymyositis. Electromyography is a mandatory diagnosis tool to rule out nerve-muscle disease. A few patients respond well and have better recovery with initial pharmacological management. However, a few patients' recovery time is quite long, even after long-term management. Long-term use of low-dose steroids is preferred for managing the disease flares in such patients. Long-term use of steroids in such patients can control polymyositis symptoms. Still, simultaneously, it also carries the risk of immune system suppression, which is a major drawback of long-term steroid use.