Polymyalgia Rheumatica

Original Editors - Nicki Spencer from Bellarmine University's Pathophysiology of Complex Patient Problems project.

Top Contributors - Nicki Spencer, Naaike Verhaeghe, Claire Knott, Admin, Elaine Lonnemann, Kim Jackson, Rachael Lowe, Ines Musabyemariya, 127.0.0.1, Wendy Walker, Evan Thomas, Ina De Maeyer and WikiSysop  

    

Search Strategy

Databases used: PubMed, Web of Science, VUB Biblio ,google, Physiopedia, 

Keywords used: Polymyalgia Rheumatica, Reumatoid arthritis, Rheumatological diseases ,
Rheumatism

Definition/Description 

(2,22,11)

Polymyalgia rheumatica (PMR) is a rheumatic inflammatory disorder that has an unknown cause.[1] It causes inflammation of the large muscles of the body and can be accompanied by constitutional symptoms, such as malaise, fatigue, fever, and weight loss.[2] In patients with PMR, the synovial membranes and bursae that line and lubricate the joints become inflamed, causing pain and discomfort. Unlike in some other inflammatory diseases, there is no associated permanent damage to the joints or the muscles.[2]
Polymyalgia rheumatic is also known as muscular rheumatism. [11] PMR is a heterogeneous disease with a major impact on QOL. [22]

Clinically Relevant Anatomy

(36,23,38)

PMR is a condition that causes many (poly) painful muscles (myalgia) [36]. PMR is characterised by pain and stiffness in the shoulder and hip girdles and an elevated acute phase response [23]

Epidemiology/etiology

  (2,3,5,8,11,16,28)

In persons over the age of 50, PMR has a prevalence of approximately 700 per 100,00. Approximately 4 in 10,000 adults over the age of 60 develop PMR each year.       

PMR is mostly seen in persons over the age of 50, PMR has a prevalence of approximately 700 per 100,000.[3] Approximately 4 in 10,000 adults over the age of 60 develop PMR each year.[2]
The prevalence is gender dependent. Women are more suitable for this condition than men. Women are twice as likely than men attained. [11]
In the United States the lifetime risk of developing PMR is estimated at 2.43% for women and 1.66% for men. [28]

Although polymyalgia rheumatic occurs worldwide, the highest incidence is seen in Scandinavian countries and in people of the northern European descent. [16]
While the lowest incidence rates occur at the more southern European countries like Italy, and Spain. [28]

The disease is more common in Caucasian.
[28]

Much research is done, but there is still no clear cause for PMR. [11]
Certain characteristics of PMR suggest that an infectious disease could be an environmental factor. It has a very sudden onset and new cases occur in cycles, which could indicate an infection as the source.[8] Attention has been focused on Chlamydia, Mycoplasma, parainfluenza virus or parvovirus B19 as possible infections responsible for PMR.[5]
Inheritance of the disorder has been suggested due to findings in some genetic studies and the pattern seen in family histories.[8] The gene(s) that could be responsible for PMR have not been definitively identified. The HLA-DRB104 and HLA-DRB01 alleles have both been found to have a possible link to PMR and GCA[5] although this remains controversial[13] ,

There may be an imbalance between immunosuppressive T-regulatory (Treg) lymphocytes and proinflammatory T-helper 17 (Th17) cells in PMR and giant cell arteritis (GCA). The frequency of Treg cells circulating appears to be reduced in patients with PMR compared with aged-matched volunteers. While on the other hand TH17 cells appear to be increased. [28]

    

Characteristics/Clinical Presentation

     The onset of PMR is very sudden. Individuals can usually remember the exact time and day that symptoms began. Individuals often wake up one morning with extreme stiffness and soreness for no apparent reason
Synovitis and bursitis of the shoulder and hip are the cause of the patient's pain.[5]
PMR is characterized by pain and stiffness involving the shoulder girdle, proximal aspects of the arms, the neck, and pelvic girdle [17]
Symptoms are usually bilateral.[13]
Other constitutional symptoms are seen in 40-50% of patients and include[1] [13]
• stiffness after rising in the morning lasting 30 min or longer [13] or after resting
• weakness
• fatigue
• malaise
• low-grade fever
• sweats
• headache
• weight loss
• depression
• vision changes

The symptoms are characteristic , although several other autoimmune, infectious , endocrine, and malignant disorders can present with similar symptoms. Ruling out the other illnesses is very important[19]. For further information see : Differential Diagnosis.
Polymyalgia rheumatic isn’t a disorder that lasts forever. Most people suffer from the disease for 2-3 years. It is important to know that it can occur for a shorter or longer term. When you can’t reduce the use of medication or you keep on having physical complaints, it is not rare that there is something else going on. You might see the doctor again for another examination, because with this clinical representation he needs to determine whether you might have rheumatoid arthritis (RA) or osteoarthritis, instead of PMR. [11]

Differential Diagnosis

There are many conditions that can mimic PMR, like rheumatoid arthritis (RA) and spondyloarthropathies (SpA). Pain and swelling of the distal joints, like feet, hands and wrists should raise concern for an inflammatory arthritis. Some patients may present swelling and pitting edema of the hands and the feet, because of a tenosynovitits. The so called remitting seronegative symmetrical synovitis with pitting edema syndrome.[28]
The first step is to assess the patient’s symptoms including pain and stiffness in the shoulder of hip girdle ( or both) .Usually of at least one week’s , and more confidently of at least two week’s , duration; in the presence of acute inflammatory markers , including erythrocyte sedimentation rate or CRP. [19]

PMR must be differentiated from :

Rheumatological diseases
Polymalgia rheumatic
Rheumatoid arthritis
Spondyloarthropathy
Crystalline arthritis (calcium pyrophosphate disease and calcium hydroxyapatite disorders)
Remitting seronegative symmetric synovitis with pitting oedema syndrome
Connective tissue diseases
vasculitis (giant cell arteritis, antineutrophil cytoplasmic antibody-associated vasculitis).
Inflammatory myopathies (dermatomyositis, polymyositis )

Non-inflammatory musculoskeletal disorders
Rotator-cuff diseases (rotator cuff tears, rotator cuff tendinopathy )
Adhesive capsulitis
Degenerative joint disease (degeneratieve disc disease)
Fibromyalgia
Endocrinopathies
Thyroid diseases
Disorders of the parathyroid gland
Infections
Viral
Bacterial sepsis, endocarditis, disc space infection, septic arthritis
Mycobacterial – eg tuberculosis
Malignant diseases
Solid, Haematological
Miscellaneous disorders
Parkinsonism
Depression
Hypovitaminosis D
Drug-induced myopathy-eg, from statins

[19]

Polymyalgia rheumatica and Giant Cell Arteritis:

Giant cell arteritis (GCA) is an inflammatory vasculopathy that normally occurs in the medium and the large arteries The ones that are usually affected are the external carotid branches (e.g., temporal and occipital arteries), the ophthalmic, vertebral, distal subclavian, and axillary arteries, and the thoracic aorta. Vasculitis leads to luminal occlusion and therefor ischemic complications.
Approximately 50% of patients with giant-cell arteritis present with polymyalgia rheumatica before, at the time of, or after the diagnosis of vasculitis.
The inflammatory reaction in the arteries is complex and is effectively suppressed with glucocorticoid treatment. The arteritis leads to remodeling of the arterial wall, giving rise to the characteristic findings on imaging and clinical manifestations.[29]

Symptoms include[2]:
• headache or tenderness on one side of the head
• scalp tenderness
• pain in the jaw when chewing, which eases quickly when the jaw is rested
• tongue or throat pain
• sudden loss of vision or any other sudden visual problem in one eye
• weakness
• numbness
• deafness

Medications

     Corticosteroids

     If PMR is suspected to be the probable diagnosis for a patient, then a trial of low-dose corticosteroids (usually prednisone) is given. The response to corticosteroids is usually dramatic, and patients may report relief in symptoms after one dose. If symptoms are not better within 2-3 weeks of beginning the corticosteroid treatment, it is unlikely that the individual actually has PMR and more testing should be performed to find an appropriate diagnosis.

     If the patient has a favorable response to corticosteroids, they will continue to take a maintenance dosage for approximately 6 months to 2 years. This maintenance dosage can help control the pain and stiffness associated with PMR. Over that time period, the dosage is gradually decreased until it is no longer needed. Complete clinical remission may take up to 5 years to occur.

     Methotrexate     

     Methotrexate may be used to reduce the corticosteroid requirements of PMR.  There have been mixed results in different studies with the use of methotrexate.

Diagnostic Tests/Lab Tests/Lab Values

     PMR is a diagnosis of exclusion. There are no definitive diagnostic tests to identify PMR. Physicians will typically perform a physical exam, order blood tests, and perform imaging studies to determine if the patient’s symptoms are due to some other disorder. In some cases, an ultrasound or MRI may reveal large joint effusions and signs of bursitis or tendovagnitis in the shoulders and hips of patients with PMR. Some clinicians use an erythrocyte sedimentation rate (ESR) of higher than 30 or 40 mm/hr as diagnostic criteria; however, there have been reports of individuals diagnosed with PMR having an ESR of normal or only slightly higher than normal so this may not be an appropriate criteria.       

     There are also two sets of diagnostic criteria that have been created for PMR. The Bird/Wood criteria includes:

• Bilateral shoulder stiffness
• Duration onset < 2 weeks
• Initial ESR > 40 mm/hour
• Stiffness > 60 minutes
• Age > 65 years
• Depression and/or weight loss
• Bilateral upper arm tenderness     

     If any 3 or more of the above criteria, or greater than 1 criteria and a clinical abnormality of the temporal artery, are present in a patient then PMR is probable.  Definite PMR is characterized by probable PMR that has a positive response to corticosteroid therapy.     

     The Hunder criteria for the diagnosis of PMR includes: 

• Patient age > 50 years
• Bilateral aching and tenderness for > 1 month of neck or torso, shoulders or upper arms, and hips or thighs
• ESR > 40 mm/hour
• Exclusion of other diagnoses     

     All the above Hunder criteria must be present to have a diagnosis of definite PMR.     

     Both of the above criteria have been found to have a sensitivity of >90%.     

     If the patient also has GCA associated with their PMR, MRI angiography and positron emission tomography (PET) can identify possible vessels involved and monitor the disease course.

Etiology/Causes

     There is no clear cause for PMR; however, research has begun to suggest that it may occur due to a combination of environmental and genetic factors.

     Certain characteristics of PMR suggest that an infectious disease could be an environmental factor. It has a very sudden onset and new cases occur in cycles, which could indicate an infection as the source. Attention has been focused on Chlamydia, Mycoplasma, parainfluenza virus or parovirus B19 as possible infections responsible for PMR. 

     Inheritance of the disorder has been suggested due to findings in some genetic studies and a pattern seen in family histories. The gene(s) that could be responsible for PMR have not been definitively identified. The HLA-DRB104 and HLA-DRB01 alleles have both been found to have a possible link to PMR and GCA.

Systemic Involvement

     The systemic involvement of PMR is stated above in the Characteristics/Clinical Presentations and Co-Morbidities sections.  

Medical Management (current best evidence)

     As stated above in the Medications section, PMR is generally treated with a long course of corticosteroids.  Depending on the facility, the course of treatment will differ.  There is no consensus on the initial dosage and subsequent tapering of corticosteroids. Some suggest an initial dose of 15-20 mg/day of prednisone and then a slow tapering over several weeks or months to find a maintenance dosage.

     If the patient also has GCA, then the initial dose of prednisone is much higher (usually 1 mg/kg of body weight). GCA in the temporal artery is a serious medical condition and could result in blindness if not treated appropriately and quickly.

     Although PMR responds very well to corticosteroids, there is still concern for the adverse effects that occur with long-term steroid use.  This includes diabetes, osteoporosis, hypertension, worsening of cataracts, muscle weakness, and infection.  Patients taking corticosteroids must have their blood sugar, blood pressure, and body weight routinely checked. Due to the increased risk for osteoporosis, vitamin D and calcium supplements should be initiated when the corticosteroids are initiated.

Physical Therapy Management (current best evidence)

     There is currently no evidence for the use of physical therapy in the treatment for PMR.  However, as physical therapists, it is still important to be aware that patients may be referred to you with a primary diagnosis of PMR, or as a co-morbidity.  It is extremely important to be aware of the risk for developing GCA because, as stated above, this is a medical emergency.  See the Co-Morbidities section above for the associated signs/symptoms of GCA.

     If a patient with PMR begins to have increased complaints of muscle pain and stiffness, it is important to ask them if they are still taking their corticosteroids as prescribed. These medications must be tapered appropriately.  Patients may not be fully aware of that and may end their medications prematurely.

      Long-term corticosteroid use also leads to many side effects, such as weight gain, cataracts, mood swings, rounding of the face, difficulty sleeping, glaucoma, diabetes, easy bruising, and hypertension.  Osteoporosis and compression fractures can also be of great concern with these patients.

     Patients may also come into the clinic with a missed diagnosis of PMR.  It is important to keep the signs/symptoms and diagnostic criteria of PMR in mind so that patients get the appropriate treatment they need.

Differential Diagnosis

According to Nothnagl and Leeb, some important differential diagnoses of PMR to keep in mind include:

• Late-onset rheumatoid arthritis (LORA)
• Hypothyroidism
• Fibromyalgia
• Tumor
• Polymyositis/dermatomyositis
• Bursitis/Tendonitis
• Systemic small-vessel vasculitis
• Remitting seronegative symmetric synovitis with pitting edema

Case Reports/ Case Studies

• Polymyalgia rheumatic and exercise: a single case report on one woman [view article in EBSCOhost]
• Isolated lower extremity vasculitis in a patient with polymyalgia rheumatica [view article in EBSCOhost]

Resources

• American College of Rheumatology- http://www.rheumatology.org/practice/clinical/patients/diseases_and_conditions/polymyalgiarheumatica.asp
• National Library of Medicine - http://www.nlm.nih.gov/medlineplus/polymyalgiarheumatica.html
• National Institute of Arthritis and Musculoskeletal and Skin Diseases Information Clearinghouse - http://www.niams.nih.gov/Health_Info/Polymyalgia/default.asp
• Arthritis Foundation - http://www.arthritis.org/conditions/diseasecenter/pmr.asp

Recent Related Research (from Pubmed)

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References

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