Polymyalgia rheumatica (PMR) is an inflammatory condition that affects persons older than 50 years of age and id characterized by pain in both shoulders with or without hip or neck pain with pronounced the morning stiffness.
Syndrome characterized by aching and stiffness of the neck, shoulders, and pelvic muscles.
It is characterized by pain and morning stiffness of the shoulder and pelvic girdles, with significant effect on quality of life and function.
PMR as an age and sex suggested prevalence rate in the US estimated at 701 per hundred thousand population aged at least 50 years.
Affects approximately 0.7% of patients older than 50 years, may occur alone or in conjunction with a giant cell arteritis.
It is the second most common inflammatory, rheumatic disease, and an older persons after rheumatoid arthritis.
Approximately 75% of patients with PMR are women.
Persons of northern European descent, have the highest incidence.
The lifetime risk of polymyalgia rheumatica is 2.4% among women and 1.7% among men.
Etiology unknown.
A diagnosis of exclusion.
A chronic inflammatory disease without universally except diagnostic criteria.
PMR does not affect life expectancy, but may affect quality of life.
No specific test for PMR exists.
Proximal muscle group pain.
Muscle biopsy normal.
Muscle strength normal as is EMG.
Similar to giant cell arthritis, but is probably a distinct entity.
Giant cell arteritis and PMR almost exclusively affect individuals aged at least 50 years and frequently have overlapping symptoms, such as fever, fatigue, weight loss, depression, and night sweats, and elevation of inflammatory markers such as erythrocyte sedimentation rate and C reactive protein.
Features of PMR occur in approximately 42% of patients with giant cell arthritis, and 3 to 46% of patients with PMR have evidence of large vessel inflammation on imaging, suggesting polymyalgia rheumatica and giant cell arthritis is a disease spectrum.
Prevalence 1 in 200 people over the age of 50 years.
Usually affects people older than 50 years of age.
Bilateral shoulder aching.
Bilateral subdeltoid bursitis is present on ultrasound in 69% of patients with PMR.
Whites affected more commonly than other races.
Females:males, 2:1.
Symptoms typically worse in the morning.
Symptoms are symmetrical.
Stiffness more pronounced after prolonged inactivity.
May have low grade fever, weight loss, fatigue, depression and rapid onset of symptoms.
Examination reveals no muscle atrophy or muscular tenderness.
Increased risk with age over 50 years, presence of giant cell arthritis.
ESR greater than 50 mm/h.
Anemia present in 50% of patients.
Chronic anemia screaming now or thrombocytosis are common
Low grade fever, fatigue and weight loss are frequently present.
PMR is included in the differential diagnosis of patients with acute onset of bilateral upper extremity pain, which is often worse following rest.
Differential diagnosis, includes osteoarthritis, or tendinopathy, giant cell arthritis, pseudogout, late onset rheumatoid arthritis, remitting seronegative symmetric synovitis with pitting edema, fibromyalgia, laid onset, spondylararthritis, myositis, or other connective tissue diseases, small and medium vessel vasculitis, infections, endocrine diseases, cancer, neurodegenerative disorders, and drug related myopathy.
DIAGNOSIS:
Diagnosis is based on presenting signs, symptoms, and laboratory results but there is no specific diagnostic test for PMR.
It is characterized by subacute or acute onset of aching pain and morning stiffness in the shoulders and neck.
Approximately 50 to 70% of patients with PMR have neck or hip girdle involvement, but peripheral joint symptoms are less frequent.
Pain in both shoulders occurs in 70 to 90% of patients.
Peripheral joint involvement is present in approximately 25% of patients typically affecting the knees or wrists with non-erosive arthritis or tenosynovitis.
Diffuse swelling of the distal extremities, mainly the hands, but occasionally the feet occurs in approximately 12% of patients.
Elevation in acute phase reactants such as C reactive protein and erythrocyte sedimentation rate, and constitutional symptoms such as fever, weight loss, and fatigue are also characteristic.
CK is normal.
Mild liver test abnormalities may occur.
Not life threatening.
Treatment:
The treatment goal for PMR is having a maintaining remission, indicating the absence of clinical symptoms and systemic inflammation.
Treatment is with corticosteroids.
Starting dose of prednisone is usually 10 to 20 mg per day.
With initiation of corticosteroids symptoms usually resolve within a few days.
A rapid response to glucocorticoids with amelioration of symptoms occurs in more than 70% within a few days and up to four weeks is observed in 40 to 96% of patients and is often considered to be diagnostic of PMR.
Requires treatment with steroids for 2-4 years.
Relapse common and the disease may reactivate with tapering of steroids.
Zero to 13% of patients may require higher initial doses of corticosteroids to control symptoms (Houston MC).
Methotrexate may be useful as a glucocorticoid agent with a dose of 10 mg per week.
Tocilizumab is considered in refractory disease, as well as sarilmab a IL-6 receptor inhibitor.
Interleukin –6 receptors block the interaction between IL-6 and its receptor, which is expressed on several immune cells, including T cells and macrophages.
Both IL-6 and these cells are enriched in the synovial and articular tissues in persons with PMR.
Prophylaxis bisphosphonates, and calcium, and vitamin D supplementation or generally utilize to decrease corticosteroid related adverse effects.
More than half of patients with PR have a relapse doing tapering of glucocorticoid therapy.
Glucocorticoid associated adverse effects are reported in the range from 3.6-to 27% of patients in some series, and as high as 58 to 91% in other series.
It is suggested that interleukin-6blockade may clinically be clinically useful in the treatment of PR.
Sarilumab shows significant advocacy in achieving sustained remission in reduction in cumulative glucocorticoid dose in patients with a relapse of PR or during glucocorticoid tapering.
Most patients require only modest doses of corticosteroids, less than 25 mg a day: A rapid response establishes the diagnosis, and the need for higher doses suggested alternative diagnosis.
Prednisone is typically tapered over many months, and relapse occurs in more than half of patients.
Among patients with active polymyalgia rheumatica despite prednisone therapy, tocilizumab, compared with placebo, results in greater percentage of patients with a CRP protein level of less than 10 with reduced prednisone requirements at 24 weeks.
Patients with elevated sedimentation rate, CRP, and interleukin-6 levels at the time of diagnosis correlate with increased risk for relapse and for a higher corticosteroid dose requirement.
Interleukin-6 has been implicated in the pathophysiology of polymyalgia rheumatica, because circulating elevated levels and increased tissue expression of IL-6 have been identified in patients.
Low ESR values, and higher hemoglobin levels are associated with better corticosteroid responses.
Women have more resistant disease, more relapses and a greater requirement for glucocorticoid drugs, and have more steroid related adverse effects, and require a longer duration of corticosteroid treatment than men.