Internal Medicine Rheumatology

Polymyalgia Rheumatica (PMR)

Polymyalgia Rheumatica (PMR)
In Polymyalgia Rheumatica (PMR) neck stifness and pain in the shoulders, hips, and proximal musculature is common.

Introduction – Polymyalgia Rheumatica (PMR)

Polymyalgia Rheumatica (PMR) is a clinical syndrome in the elderly characterized by headache and stiffness in the neck, shoulders and pelvic girdle area, often in association with general malaise symptoms. The disease rarely affects people under 60 years of age and the incidence increases with age.

It is still disputed what the pathoanatomical correlate is to the clinical syndrome PMR. Studies using ultrasound and PET imaging indicate the presence of synovitis in the central major joints, and vasculitis of the aorta and its larger branches.

PMR and temporal arteritis (TA) sometimes occur together and it is well known that the diseases are associated with each other. In the PMR/TA population, 45% have only PMR symptoms, 38% express TA symptoms and 17% have mixed symptomatology. The link between the two diseases is not fully established.

Symptoms – Polymyalgia Rheumatica (PMR)

Subacute onset of inflammation-related general symptoms sometimes preceded by influenza-like symptoms:

  • Tiredness
  • Malaise
  • Anorexia
  • Weight loss
  • Low-grade fever

In addition, in PMR:

  • Pain with a prominent element of stiffness in the proximal musculature, usually symmetric affecting the shoulders and pelvic girdle, upper arms, and thighs.
  • Clear daily rhythm with symptom culmination during the late-night and early morning
  • Activity limitation due to pain can occur, especially in the mornings. More uncommon – passive movement restriction.
  • Normal muscle strength.
  • Limping due to claudication may indicate giant cell arteritis in large vessels.

Clinical findings

Often no significant deviations in physical examination, musculature not atrophic. Sometimes, local tenderness may be present.

Differential diagnoses – Polymyalgia Rheumatica (PMR)

DiagnosisExcluded By
Tension myalgiasPhysical examination of muscles
Cervical SpondylosisNeurological examination of the upper extremities
HyperparathyroidismS-Calcium, S-Albumin
PolymyositisMedical history; weakness usually more prominent than pain, S-CK
New onset of rheumatoid arthritis in the elderlyCareful joint examination, especially the joints of the fingers and toes
DepressionMedical history
Paramalign myalgias, myelomaMedical history, physical examination, be observant regarding classical PMR symptoms, protein fractionation, atypical response to cortisone medication, difficulties in reducing cortisone dose
Low-virulence general infection, eg endocarditisCardiac examination, blood culture, echocardiography
Herpes zoster in prodromal stageDermatomal proliferation, exanthema within a few days
Myopathy with proximal weaknessMedical History (usually not pain), muscle strength, check for muscle atrophies

The following findings indicate a diagnosis other than PMR:

  • No or minimal morning stiffness
  • No or minimal aggravation of the symptoms in movement
  • Diffuse widespread pain
  • Fever with/without wheezing
  • Arthritis of the wrist, MCP, MTP or PIP joint
  • Non-tender lymphadenopathy
  • Cytopenia in the CBC
  • Monoclonal bands in protein fractionation
  • Elevated transaminases with CK increase
  • Skin or hair pathologies
  • Pulmonary symptoms
  • High ANA titers
  • Unexplained hematuria
  • Lack of effect after therapy with prednisolone 12.5-20 mg/day after 4-5 days

Diagnostics – Polymyalgia Rheumatica (PMR)

  • There is no specific blood test.
  • Medical History and physical examination as above, palpate the temporal and carotid arteries and auscultate the carotids. Blood pressure in both arms, lateral difference may indicate arteritis or other stenosis in the distal vessels arising from the aortic arch.
  • SR (or CRP). Note, however, that SR can be normal at the onset of disease and later rise within a few weeks. PMR patients may have normal SR, according to the literature in about 10% of cases.
  • CK and B-glucose to exclude polymyositis and to diagnose previously unknown diabetes prior to steroid therapy, respectively.
  • Chest X-ray considering the possibility of TB, which must be excluded before long-term steroid therapy.
  • Consider administering a test dose of steroids of 12.5-15mg. At higher doses, other myalgic syndromes may also be improved. At the test dose, a marked improvement, but not necessarily complete symptom relief, should occur within 4-5 days. The dose may then be adjusted upwards.
  • Autoantibody lab tests have no value if there is no clinical suspicion of SLE or systemic vasculitis.

Otherwise, the diagnostic procedures are guided by the medical history.

Treatment – Polymyalgia Rheumatica (PMR)

Glucocorticoids are the first choice of therapy for PMR. NSAIDs may provide some relief from symptoms. However, NSAIDs are often unsuitable in the age group affected by PMR.

It is important to consider the differential diagnoses before starting treatment with glucocorticoids. About 25% of patients who are initially believed to have PMR appear to get a different diagnosis, explaining the symptoms, after some time. Be careful with the analysis and documentation of cortisone doses (<20 mg prednisolone as test dose), time for response to therapy, how comprehensive the symptom relief gets and the type of initial response to therapy.

Dosing recommendation for prednisolone variy within the country. Scientific support is available for several different approaches. First and foremost, follow the treatment recommendation at a local rheumatology clinic.

Other remarks

  • Expect a treatment duration of 1.5 – 2.5 years before a successful discontinuing of the treatment can be achieved.
  • The dose should be kept minimal and the patient should be symptom-free all the time.
  • Every-other-day dosing of prednisolone is not appropriate for PMR.
  • Steroid therapy always carries the risk of agitation, insomnia, night sweats, “stretch marks” and in the long term, osteoporosis. There is also a risk of inducing diabetes, cataract progression, and hip necrosis.
  • All patients should receive osteoporosis prophylaxis through smoking cessation, encouragement of outdoor physical activity (sunlight), calcium supplementation and vitamin D. All patients should receive prescriptions for bisphosphonate.
  • There is no lowest steroid dose without the risk of osteoporosis development and vertebral compression.
  • There is no support in studies that methotrexate or TNF-alpha inhibitors could be used in lieu of steroids, but the studies have been too small-scale.

Follow-Up – Polymyalgia Rheumatica (PMR)

  • The patient’s symptoms determine the cortisone dose. It is therefore important that the same physician maintains continuous contact with the patient in order to be able to evaluate the nuances of the clinical picture. Strive for symptom relief and minimize the steroid dose gradually.
    At each dose change:
    • Reassess medical history of recurrence symptoms
    • Physical examination – radial pulse bilaterally, blood pressure in both arms and auscultation of the carotid vessels
    • SR; glucose
  • If the patient suffers from typical symptoms with normal SR, increase the steroid dose.
  • The patient should be informed about the risk of temporal artery disease, which symptoms should be noted and that in such a situation the patient should immediately contact the health care system. In case of visual impairments – emergency department visit regardless of time of day.
  • Pay attention to steroid side effects throughout the course
  • Cortisone medication often causes SR below 10 mm. Do not forget that the current age group has normal values ​​for SR up to 30-35 mm. Thus, allow SR to reach these values ​​if the patient is symptom free. If SR rises above the reference level in a symptom-free patient, consider and assess for other causes of SR elevation and reconsider the diagnosis.
  • In case of excessive dose changes, “steroid-discontinuation pseudorheumatism” occurs, which gives PMR-identical symptoms without being indicative of recurrence. If the dose reduction been severe, consider this phenomenon when making decisions on scheduling new medical appointments.
  • Steroids have no curative effect but keep the inflammation suppressed during spontaneous healing, which in untreated cases occurs after 1.5-3 years. The expected treatment time is thus in this range.
  • Question the therapy or diagnosis if steroids are required for more than 3 years. In such cases, the patient should be referred for evaluation at the rheumatology clinic.
  • PMR has a fluctuating natural course, which means that relapse with symptom onset is common if the steroid dose is kept at a low level. In this situation, SR is of little use, as SR is normal in up to 50% of cases of recurrence. Adjust the dose to one step above the last dose that gave symptom relief.
  • The most common causes of treatment failure are premature attempts to terminate therapy, rapid dose reduction, or incorrect diagnosis.

Further Reading