What is Polymyalgia Rheumatica?
Polymyalgia rheumatica (PMR) is a type of arthritis that causes pain and stiffness around the neck, shoulders, and hips. This condition can significantly affect a person’s everyday life, especially if they’re over the age of 50 and white, as these demographics are generally more frequently diagnosed with PMR. It’s an inflammation-related condition that can be detected by higher levels of certain markers in your blood tests called erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP).
Sometimes, people with PMR can also have a condition known as giant cell arteritis (GCA), or Horton’s disease. Some experts believe GCA is a more severe part of the same set of issues as PMR.
Understanding the complexity of PMR is important for doctors so they can manage their patients’ condition properly. Careful attention to potential long-term complications and the important connection with GCA is crucial. The aim here is to outline key aspects of PMR, including its causes and symptoms, and the most effective ways to manage it.
What Causes Polymyalgia Rheumatica?
The exact cause of Polymyalgia Rheumatica (PMR), a condition that causes muscle pain and stiffness, isn’t entirely clear. Some studies suggest that it might be due to certain genetic factors. For example, specific types of a gene called the HLA class II are often found in people with PMR. In particular, the HLA-DRB1*04 type of this gene is seen in up to 67% of cases. Variants of other genes, such as ICAM-1, RANTES, and IL-1 receptors, also seem to be involved in some cases of the disease.
Some researchers have observed that the number of people with PMR increased during times when infections like mycoplasma pneumonia and parvovirus B19 were spreading widely. This has led to the suggestion that infections might play a role in causing PMR. Similarly, the Epstein-Barr virus (EBV), a common virus that can cause infectious mononucleosis or “mono”, has also been proposed as a possible trigger for PMR. However, not all studies agree with the idea that infections are involved in causing PMR.
There are also reports of PMR being associated with a gut condition called diverticulitis, which could mean that changes in gut bacteria and chronic inflammation in the bowels might contribute to the development of this disease.
Some people have developed PMR after getting the influenza or “flu” vaccine. It’s possible that substances used to boost the effectiveness of vaccines (known as adjuvants) might trigger the immune system to react abnormally and give rise to a condition that is similar to PMR. This is referred to as autoimmune/inflammatory syndrome induced by adjuvants (ASIA).
Risk Factors and Frequency for Polymyalgia Rheumatica
Polymyalgia Rheumatica (PMR) happens most often in individuals over the age of 50. Each year, 58 to 96 out of every 100,000 people, particularly from White communities, are diagnosed with PMR. The frequency of this condition increases with age up to 80 years old.
- PMR is quite common, being the second most frequent type of inflammatory autoimmune disease after rheumatoid arthritis, especially within White communities.
- It is at least twice as prevalent as Giant Cell Arteritis (GCA) and can be found in about 50% of patients with GCA.
- PMR, however, is quite rare within Black, Asian, and Hispanic communities.
Signs and Symptoms of Polymyalgia Rheumatica
Polymyalgia rheumatica (PMR) is a condition that causes pain and stiffness in the body, most commonly in the shoulders, neck, and hips. These symptoms are usually symmetric, meaning they affect both sides of the body. The pain and stiffness tend to be worse in the morning, or after long periods of rest or inactivity. This can result in a restricted ability to move the shoulders.
People with PMR might experience symptoms in various areas like upper arms, hips, thighs, upper and lower back. The onset of symptoms is often rapid, with people noticing changes anywhere from a day to up to 2 weeks. PMR can affect daily life, interfering with simple tasks like getting out of bed, dressing, bathing, and driving. The specific cause of pain and stiffness is inflammation in and around the shoulder and hip joints, and surrounding softer structures near the upper limbs.
- Diffuse pain in shoulders, neck, and hips
- Stiffness, typically worst in the morning
- Difficulty performing daily activities
- Restricted ability to move the shoulders
- Quick onset of symptoms (from a day up to 2 weeks)
About half of patients with PMR also experience general symptoms like fatigue, feeling unwell, lack of appetite, weight loss, and low-grade fever. However, a high, persistent fever is uncommon and may indicate a different condition. Also, about a quarter of patients show signs of arthritis. Other features may include edema or swelling due to fluid buildup in the lower limbs, carpal tunnel syndrome, and inflammation of the tendon sheaths. These do not lead to deformities or rheumatoid arthritis. All these signs, including an uncommon condition called remitting seronegative symmetrical synovitis with pitting edema (RS3PE), respond well to steroid treatment.
During a physical exam, there’s usually overall tenderness in the shoulder area, which is a nonspecific sign. Because of the pain, the patient may findings they can’t move their shoulder, neck, or hip to its full range. The underlying muscle strength is usually intact, though there might be tenderness in the neck, arms, and thigh muscles.
Testing for Polymyalgia Rheumatica
Lab tests often reveal High Erythrocyte Sedimentation Rate (ESR- a blood test that checks inflammation in your body) in those suffering from PMR. Most doctors believe an ESR reading of higher than 40 mm/h is significant and suggestive of PMR. In certain patients, ESR values may be even higher. These patients are more likely to experience whole-body symptoms like fever and weight loss. However, their response to treatment and risk of relapse is similar to patients with lower ESR values. Beside ESR, C-reactive protein (CRP – a substance in the body responding to inflammation) levels are typically high in patients with PMR. In comparison, some other blood tests, like those for anemia and liver health, may show irregularities.
Medical imaging can also help diagnose PMR. Doctors often use ultrasound to judge the inflammation of the bursae, the sacks around your joints, and tendons in your shoulders and hips. Findings from ultrasounds can help determine the best course of treatment and frequency of relapses. However, MRI scans offer a more detailed view of the inflammation, making it valuable in cases where ultrasound is not clear enough. Particularly, an MRI is more sensitive in showing inflammation in the hip and pelvic region. Positron emission tomography (PET) scans can also help identify PMR by spotting the uptake of a tracer substance in affected joints.
Considering both laboratory and imaging findings, doctors may use a scoring system to verify if a patient has PMR. This system awards points for symptoms like prolonged morning stiffness, hip pain or restrictions in movement, and absence of antibodies linked to other forms of arthritis. If available, findings from an ultrasound scan can also contribute to the scoring.
There’s often an overlap between PMR and Giant Cell Arteritis (GCA), another inflammatory condition. Thus, doctors closely observe those with PMR for symptoms of GCA, which can include headache, vision problems, and scalp tenderness. If any of these symptoms appear, further imaging tests could be needed for a thorough evaluation.
Treatment Options for Polymyalgia Rheumatica
Oral glucocorticoid therapy, a type of steroid medication, is widely recognized as an effective treatment for certain conditions. According to the 2015 EULAR-ACR management guidelines, the therapy usually starts with an initial dose followed by gradual reduction. This reduction should reach 10 mg daily within 4 to 8 weeks and eventually stop altogether. Then, it’s typically taken for at least a year. If there’s a relapse or the condition returns, the dose is increased again and then gradually reduced. All these adjustments should be done considering the patient’s condition, regular check-ups, laboratory results, and any side effects.
In some cases, doctors may recommend lower doses for patients who are smaller in size, have mild symptoms, or have conditions like brittle diabetes. In such scenarios, methotrexate may be introduced early on as an additional treatment, especially for patients more likely to relapse or require a longer duration of therapy. This is also applicable for those with other conditions or medications, which can increase the chances of side effects from the glucocorticoid therapy.
Methotrexate is usually administered orally and has been shown to be an effective supplement to glucocorticoids in clinical trials. For patients who can’t take methotrexate, leflunomide or azathioprine can be considered as alternatives. Nevertheless, the guidelines recommend against using anti-TNF agents.
Tocilizumab (TCZ) is another drug that has been shown to be useful in managing conditions when they coexist with GCA. It has shown promise in some trials for those patients who do not completely respond to glucocorticoids. However, to establish its consistent benefits, more controlled trials are necessary.
For patients on long-term steroid therapy, calcium and vitamin D supplements are routinely advised to maintain bone health. Certain types of medication, called bisphosphonates, are recommended for patients who have a moderate to high risk of fractures, especially if their risk assessment score suggests so.
Continuous monitoring of patients undergoing these treatments is crucial. Follow-ups are typically scheduled every three months until the disease goes into remission and then every six months to a year to check for a potential return of the disease. Certain blood tests, CRP and ESR, are utilized to keep track of the disease’s activity.
Relapses, or the return of symptoms, can be at an increased risk if the initial dose of steroid used was high, the steroid tapering was done rapidly, or the patient has persistently high inflammatory markers. Managing these relapses can be a challenge, but generally, the original dose can be restarted or the interval between dose reductions can be prolonged to manage the condition.
What else can Polymyalgia Rheumatica be?
In considering a diagnosis for Polymyalgia Rheumatica (PMR), doctors must rule out other conditions that can cause similar symptoms. Having these tests and examinations help doctors to identify the correct illness. Here are some conditions that might mimic the signs of PMR:
- Crown dens syndrome
- Hypothyroidism (an underactive thyroid)
- Obstructive sleep apnea (a sleep disorder that causes breathing to repeatedly stop and start)
- Depression
- Viral infections such as EBV (Epstein-Barr virus), hepatitis, HIV (human immunodeficiency virus), and Parvovirus B19
- Systemic bacterial infections, including septic arthritis (joint infection)
- Cancer
- Diabetes
- Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome; a rare inflammatory arthritis condition
What to expect with Polymyalgia Rheumatica
Polymyalgia rheumatica (PMR), a type of inflammatory disorder, has a great recovery rate when it’s diagnosed quickly and treated correctly. This means if you have PMR and your doctor spots it early and starts the right treatment, you will likely recover well. Also, you should know that people with PMR do not have a higher risk of passing away compared to the general population.
Possible Complications When Diagnosed with Polymyalgia Rheumatica
People with Polymyalgia Rheumatica (PMR) have a greater chance of developing heart diseases. Various studies suggest that this increased risk ranges from 1.15 to 2.70 times. This is most likely due to premature hardening of the arteries, caused by long-term inflammation.
It’s not entirely clear if there is a link between PMR and cancer. However, one study showed that PMR patients had roughly 2.9 times greater risk of developing a type of cancer called lymphoplasmacytic lymphoma, or Waldenstrom Macroglobulinemia.
Additionally, PMR patients are more likely to develop inflammation in their joints, a condition known as inflammatory arthritis. Factors such as inflammation in the small joints, being younger, and having certain antibodies (anti-CCP) were linked to a higher risk of developing inflammatory arthritis in the case of PMR patients.
Key Points:
- PMR increases the risk of heart diseases
- PMR might be linked to certain types of cancer
- PMR patients have an increased risk of inflammatory arthritis
Preventing Polymyalgia Rheumatica
Strategies to discourage and prevent PMR (Polymyalgia Rheumatica), a condition that often affects people over 50 and causes inflammation in the body, mainly focus on recognizing symptoms early, correctly identifying the condition, and starting the right treatment as soon as possible. Actively checking symptoms in people over 50, and improving awareness about PMR, could help in recognizing the disease early. Medical professionals can also help by being aware of the symptoms and diagnostic criteria for PMR, which can speed up detection.
Regular checks for signs of inflammation, like ESR (Erythrocyte Sedimentation Rate) and CRP (C-Reactive Protein), could be helpful for early detection in older people who are experiencing muscle or joint pain. Moreover, teaching the public about habits that might affect their inflammation levels, and encouraging regular exercise and a good diet could help prevent PMR or make the symptoms less severe.
Patients should be fully informed about the risks and benefits of GC (Glucocorticoids) treatment, a medication used for PMR. Patients should also be supported to stick to their medicine plan and regular check-ups, to lower the risk of the disease coming back and possible side effects from medication. It’s also important for patients to know that taking calcium and vitamin D supplements is beneficial.
Overall, a combined approach that includes increasing public knowledge about PMR, educating healthcare providers, and actively checking symptoms might be a good way to discourage and possibly prevent PMR.
