Polymalgia Rheumatica Dr. Barb Blumenauer MD, FRCPC

Introduction Inflammatory condition associated with pain and morning stiffness in neck, shoulders and hip girdle Can be associated with Giant Cell Arteritis (GCA) Generally patients > 50 with peak incidence between 70-80 Second most common inflammatory condition (#1 RA) Female 2-3:1 Males Most common in Scandinavian and Northern European descent with high of 113 per 100,000 in Norway Rare in Asians, African-Americans and Latinos

PMR and GCA PMR 2-3 times more common than GCA Approximately 50% of GCA patients have PMR 5-30% PMR patients have GCA Etiology unknown but are HLA associations Increased interleukin 6 levels in blood of PMR patients

Signs and Symptoms Stiffness at least 30 minutes Gel phenomena Pain shoulder > hip and neck May have synovitis, bursitis, swelling, tenosynovitis or carpal tunnel syndrome Antalgic decreased range of motion actively but usually not passively (if patient can adequately relax) Subjective weakness but usually normal if can "ignore" pain during exam Systemic symptoms

Investigations Elevated ESR common often greater than 40 Elevated CRP may be more common than elevated ESR May have normocytic anemia; WBC/platelets usually normal Serology usually negative but prevalence positive RF and ANA increase with age Occasionally transaminitis Joint x-rays normal aside from normal age changes US, MRI etc can show synovitis but aren't generally done

Diagnosis: Provisional ACR/EULAR Criteria Required Criteria Additional Criteria EMS of 45 or more minutes ( 2 points) RF(-) or anti-CCP (-) (2 points) Pain or limited ROM at hip ( 1 point) Absence peripheral joint pain ( 1 point) Age 50 or above Bilateral shoulder aching Abnormal ESR or CRP Required criteria plus score of 4 or more 78% specificity and 68% sensitivity! Adding US increases specificity to 91%. However really meant for research versus diagnosis

Differential Diagnosis Main is RF(-) RA RS3PE Syndrome Multifocal local MSK disease Bone disease ( multiple myeloma, metastatic disease, osteomalacia, hyperparathyroidism etc) Drug induced myalgias/myositis i.e. statins etc Inflammatory myopathy like dermatomyositis Fibromyalgia Endocarditis Hypothyroidism Paraneoplastic syndrome ANCA associated vasculitis

RA versus PMR RA usually symmetrical with small joint involvement RA less responsive to Prednisone Up to 20 % patients diagnosed with PMR may eventually be changed to RA Often difficult to taper prednisone in RA patients without DMARD therapy PMR should have negative serology PMR non erosive The disease with the least agreement between a rheumatologist and a non rheumatologist

PMR versus Fibromyalgia 20 year olds don't get PMR No "true" EMS/ gel phenomenon i.e. fibromyalgia (FM)worse with activity, better with rest which is opposite of PMR FM usually widespread pain and usually chronic not acute Labs normal in FM Classic tender points in FM, not in PMR PMR usually pain free passive ROM PMR not tender to touch FM not overly prednisone (PDZ) responsive " takes the edge off" whereas PMR by definition exquisitely PDZ sensitive

PMR Versus Myositis Myositis presents with PAINLESS weakness PMR presents with pain and NO WEAKNESS aside from antalgic weakness Almost always elevated CPK in myositis and not in PMR Patients with PMR can get weakness secondary to steroid myopathy but it gets better with PDZ reduction whereas myositis weakness gets worse with PDZ reduction Myositis can have rash and other findings such as Gottren's plaques, mechanics hands etc Myositis can have extra-articular manifestations (lung disease etc.) and PMR does not

Rotator Cuff Tendinitis(RCT) Can mimic PMR but RCT no systemic symptoms and normal labwork When tapering PDZ consider RCT if otherwise well and inflammatory markers normal Usually positive rotator cuff impingement signs If present intra-articular steroids well settle it allowing PDZ taper

Vitamin D Deficiency Can can cause myalgias but usually diffuse without systemic symptoms, EMS, gel etc Common in Canadians especially elderly so may coexist with PMR Vitamin supplementation for all patients especially with PDZ use

Treatment Main stay treatment is PDZ Exquisitely PDZ sensitive often 10-15 mg, rarely 20 mg daily If patient not 100% settled with 20 you either have the wrong diagnosis or something else is going on Usually need treatment for 12-18 months Once settled decrease PDZ at monthly intervals or longer, usually 2.5 decrease until you reach 10 mg daily and then usually 1 mg monthly thereafter as tolerated If you can't get the patient off PDZ rethink the diagnosis – it might be RA!

PMR Treatment Continued No good evidence for any other drug reducing steroid cumulative dose, flares etc. A few studies show minimal effect of methotrexate Some evidence for anti-interleukin 6 treatment working in GCA and perhaps effect in PMR but cost prohibitive!

Don't Forget About GCA Patients need to be aware of warning symptoms of GCA and to seek immediate attention if occurs Common symptoms include scalp pain, painful scalp sores, jaw claudication, severe NEW headache and sudden visual loss Requires urgent treatment EVEN BEFORE diagnosis confirmed to prevent permanent bilateral blindness – visual loss does not settle Usually elevated ESR but could be partially treated if on PDZ for PMR Can have GCA even if temporal artery biopsy negative Beware involvement of other vessels and be aware of increased risk or aortic artery its branches developing aneurysms.

GCA Treatment PDZ 60-80 mg daily ASA 325 daily may decrease chance of blindness but beware additive risk of GI bleeding – consider PPI gastroprotection Watch for PDZ induced DM or glaucoma

Osteoporosis Prophylaxis Lose majority of bone in the first 3 months so start ASAP Can use bisphosphonate, Prolia or Forteo Parenteral administration usually more effective Vitamin D 2000 IU daily Calcium 500 mg p.o. bid with meals Baseline BMD and repeat q 6/12 or as indicated. If losing bone consider other causes of osteopenia, compliance with treatment, absorption etc and consider changing route of drug administration or class of drug

Prednisone Plea If you think patient needs PDZ for MSK disease please consider urgent rheumatology referral BUT if GCA symptoms treat ASAP pre rheumatology assessment Want to ensure patient doesn't have RA as PDZ not effective disease modifying agent and treatment patients get within the first 12 weeks of symptom onset determines how patient do forever! ( forever scarred) We have the BEST DRUGS and early treatment is abolishing damage for many patients – besides the orthopods are too busy to replace joints that could have been saved.