PMR and GCA: diagnosis and steroid management in general practice

Polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) are closely linked inflammatory conditions of older adults, both rare under the age of 50 and peaking in the seventh decade. They share pathological features and patient demographics — women are affected roughly twice as often as men, and both conditions are more common in people of Northern European ancestry.

PMR is approximately three times more common than GCA. Around 15–20% of people with PMR develop GCA at some point, while 40–50% of people with GCA have PMR-type features. This clinical overlap makes vigilance in both directions essential: a patient presenting with PMR must be screened for GCA symptoms at every visit, and a patient with GCA should be assessed for the typical girdle features of PMR.

PMR is managed primarily in general practice, with rheumatology involvement for complex or refractory cases. GCA, by contrast, is a medical emergency — it can cause permanent blindness within hours of vascular occlusion and must be treated with high-dose steroids the same day, without waiting for specialist confirmation, when visual symptoms are present. The eTG and BSR/BHPR 2020 guidelines are the primary guideline sources used here.

A. Core clinical — the AU general-practice framework

Polymyalgia rheumatica (PMR)

Clinical features:

The cardinal presenting complaint is bilateral shoulder pain and stiffness — present in over 70% of patients — often making it impossible to raise the arms above shoulder height or get out of a low chair. Hip and pelvic-girdle pain affects approximately 50% of patients. The hallmark is morning stiffness lasting 45 minutes or more, worsening after rest and partially relieved by gentle movement. Constitutional symptoms — fatigue, low-grade fever, weight loss, depressed mood — are common accompaniments.

Examination typically shows restricted active shoulder range of motion (passive range is often better preserved), deltoid tenderness, and sometimes mild pitting oedema of the hands. Synovitis is not a prominent feature, which helps distinguish PMR from late-onset rheumatoid arthritis.

Investigations:

• ESR ≥40 mm/h (present in ~80–90% of cases) and CRP ≥10 mg/L — the inflammatory markers of choice
• CK — normal (a raised CK suggests inflammatory myopathy or statin myopathy, not PMR)
• TSH — to exclude hypothyroidism, which mimics PMR with proximal stiffness and fatigue
• RF and anti-CCP — negative (positive titres suggest rheumatoid arthritis)
• FBC — mild normocytic anaemia and thrombocytosis are common; significant cytopenias prompt reconsideration of the diagnosis
• Vitamin D — replete where deficient, particularly given upcoming steroid therapy

Diagnostic criteria:

The 2015 ACR/EULAR provisional classification criteria (Dasgupta et al.) require: age ≥50, bilateral shoulder pain, and abnormal CRP or ESR. Additional scoring items include morning stiffness exceeding 45 minutes (2 points), hip pain or restricted range of motion (1 point), absence of RF and anti-CCP (2 points), and absence of other joint involvement (1 point). A score of ≥4 points supports the PMR diagnosis; ultrasound-confirmed bursitis adds additional points.

Differential diagnosis of PMR includes late-onset rheumatoid arthritis (check RF, anti-CCP; small joint synovitis), rotator cuff disease or frozen shoulder (usually unilateral; normal inflammatory markers), hypothyroidism (check TSH; raised CK), inflammatory myopathy (proximal weakness more than pain; CK very elevated), fibromyalgia (multiple body sites, normal inflammatory markers, often younger), malignancy (paraneoplastic proximal myalgia — if markers very high, weight loss prominent, or no response to steroids, investigate thoroughly), and statin myopathy (drug history; CK raised).

Giant cell arteritis (GCA)

Clinical features:

Think GCA in any new headache in a person over 50. BSR 2020 guidance and eTG highlight the following features:

• New-onset temporal or unilateral headache (60–90%) — the most common presenting symptom
• Scalp tenderness — combing hair causes pain; pressing over the temporal artery reproduces symptoms
• Jaw claudication (~50%) — pain on chewing or prolonged talking that improves with rest; the most specific symptom of GCA
• Visual symptoms (~25%) — amaurosis fugax (transient monocular visual loss), diplopia, blurring, or sudden permanent visual loss from anterior ischaemic optic neuropathy (AION)
• Constitutional features — fever, weight loss, night sweats, fatigue
• PMR features in 40–50% of GCA patients

On examination, the temporal artery may be tender, thickened, nodular, reduced in pulsation, or non-compressible. Any new visual deficit or relative afferent pupillary defect (RAPD) warrants urgent ophthalmology review the same day.

Investigations for GCA:

• ESR typically ≥50 mm/h (present in ~90%); CRP — often more sensitive, elevated in ~98%
• Haematology — anaemia of chronic disease, thrombocytosis
• Temporal artery biopsy (TAB) — gold standard; requires a segment ≥3 cm (skip lesions mean a short segment may miss the diagnosis); positive in 30–40% of clinical GCA cases; yield is highest within 1 week of starting steroids, remains useful up to 2–4 weeks; negative TAB does not exclude clinical GCA
• Temporal and axillary artery ultrasound — the halo sign (hypoechoic ring around the vessel lumen from inflammatory oedema) has high sensitivity and specificity in experienced hands; increasingly used as a non-invasive first-line investigation
• PET-CT — detects large-vessel involvement (aorta, subclavian, iliac) in suspected large-vessel GCA variant

Key point: A normal CRP does not exclude GCA if clinical suspicion is high. Start treatment first; investigate after.

B. Treatment — prednisolone protocols and steroid-sparing agents

PMR: prednisolone starting dose and taper

First-line treatment: prednisolone 15 mg/day per BSR/BHPR 2020 and eTG. Most patients experience substantial improvement within 24–72 hours. Failure to respond meaningfully within one week should prompt reconsideration of the diagnosis — consider rheumatology referral.

Tapering protocol (individualise — use symptoms and inflammatory markers together):

Phase	Duration	Dose
Initial response	4 weeks	15 mg/day
Step 1	4 weeks	12.5 mg/day
Step 2	4–8 weeks	10 mg/day
Slow taper	4–8 weeks per step	Reduce by 1 mg every 4–8 weeks from 10 mg
Total expected duration	1–2 years	—

Relapse — return of symptoms with ESR/CRP elevation — occurs in up to 50% of patients during tapering. When relapse occurs, return to the last effective dose rather than going back to the starting dose. A slower taper is then appropriate.

Methotrexate (steroid-sparing) — consider for PMR patients with significant steroid-related side effects, relapsing disease, or expected difficulty tapering. The BSR 2020 guidelines support its conditional use. Weekly oral methotrexate 10–15 mg with folate supplementation is the standard approach.

GCA: emergency management

Same-day treatment on clinical suspicion — do not wait for biopsy results:

• No visual symptoms: prednisolone 40–60 mg/day orally (40 mg for lighter or smaller patients; 60 mg for larger or more severe presentations)
• Visual symptoms present or visual loss occurring: intravenous methylprednisolone 500–1000 mg daily for 3 consecutive days, then oral prednisolone 60 mg/day. This requires hospital admission or same-day specialist arrangement
• Aspirin 75–100 mg daily — recommended by BSR 2020 for all GCA patients to reduce the risk of ischaemic stroke and visual loss (add proton pump inhibitor if high GI risk)

GCA tapering is slower than PMR — total treatment course typically 2–3 years with relapse common in 30–50% of patients during tapering.

Tocilizumab (RoActemra) for GCA — the GiACTA trial (Stone et al. NEJM 2017) randomised 251 patients and showed subcutaneous tocilizumab 162 mg weekly achieved sustained steroid-free remission in ~56% vs ~14% with placebo at 52 weeks, with significantly lower cumulative prednisolone exposure. Under the PBS, tocilizumab is Authority Required (Telephone/Written) for relapsing or refractory GCA — specialist (rheumatologist) initiation is required. It requires regular FBC, LFTs, and lipid monitoring.

C. Steroid-related care — the six monitoring domains

Long-term prednisolone at doses required for PMR and GCA creates predictable and manageable risks. Six monitoring domains apply from the first prescription:

1. Bone health — calcium 1,200 mg and vitamin D ≥800 IU daily from day one. For prednisolone ≥7.5 mg/day expected for ≥3 months, add a bisphosphonate (alendronate or risedronate oral weekly) or denosumab under PBS Authority for steroid-induced osteoporosis. Osteoporosis Australia supports this approach. DEXA scan at baseline and at 12 months (or per clinical course). Do not wait for a fracture to initiate bone protection.

2. Blood glucose — fasting glucose or HbA1c at baseline then 3-monthly for the first year. Steroid-induced hyperglycaemia and new-onset type 2 diabetes are common, particularly in those with pre-existing insulin resistance or impaired fasting glucose. Dose adjustments for existing antidiabetic treatment may be needed at each steroid dose change.

3. Blood pressure — steroids cause fluid retention and can worsen hypertension. Check at every visit and initiate antihypertensive treatment per standard guidelines if needed. Salt restriction advice is relevant. Monitor weight gain.

4. Lipid profile — dyslipidaemia is common during long-term steroid therapy. Review lipids annually and manage per cardiovascular risk stratification.

5. Eye health — cataracts and glaucoma are recognised complications of long-term corticosteroids. Annual eye review with an optometrist or ophthalmologist is recommended for patients on prolonged therapy. GCA patients require urgent ophthalmology review at diagnosis for full assessment of visual pathway involvement.

6. Infection risk and vaccinations — complete or update all recommended vaccines before commencing high-dose immunosuppression where possible. Per RACGP immunisation guidelines and ATAGI: influenza annually; pneumococcal (Prevenar 20 plus Pneumovax 23 for those not previously vaccinated); COVID-19 per current schedule; Shingrix (recombinant zoster vaccine, non-live) for adults ≥65 or those on immunosuppression ≥18 — Shingrix is preferred over Zostavax (live attenuated) as it is safe on immunosuppression. Consider TMP-SMX 480 mg daily for Pneumocystis jirovecii pneumonia prophylaxis when prednisolone is ≥20 mg/day for 4 weeks or longer.

D. Australian operations

MBS items

For PMR and GCA management in general practice (MBS Online):

• GP consultations: items 23, 36, 44 (Level B/C/D); initial assessment commonly Level C or D
• ESR, CRP, FBC, inflammatory markers: item 73807
• DEXA bone densitometry: item 12500 (Authority for steroid-induced osteoporosis screening)
• Temporal artery biopsy (MBS item 30094): performed by vascular surgeon, plastic surgeon, or ophthalmologist
• Ultrasound temporal/axillary arteries: item 55070 or MSK ultrasound codes (specialist referral for this indication)
• GPCCMP for ongoing management: items 965/967
• 75+ Health Assessment: item 707
• ATSI Health Assessment: item 715
• Telehealth review consultations: items 91801–91828

PBS prescribing

Under the PBS and per AMH:

• Prednisolone 5 mg/25 mg tablets — General Schedule; prescribe both strengths for flexible dosing during taper
• Methotrexate (oral) — Authority Required (Streamlined) for rheumatological conditions; PMR use is off-label but accepted in practice
• Aspirin 100 mg — General Schedule
• Tocilizumab (RoActemra SC) — Authority Required (Telephone/Written) for GCA in relapsing or refractory disease; rheumatologist-initiated; approximately $1,500/month if not PBS-funded
• Calcium carbonate / vitamin D preparations — General Schedule (most combination preparations)
• Alendronate or risedronate — Authority Required (Streamlined) for steroid-induced osteoporosis when prednisolone ≥7.5 mg/day for ≥3 months and ≥1 additional risk factor (verify current PBS criteria, as they are periodically updated)
• Denosumab (Prolia) — Authority Required for steroid-induced osteoporosis
• Proton pump inhibitors (esomeprazole, pantoprazole) — General Schedule for GI protection on concurrent steroid + aspirin
• TMP-SMX (Bactrim DS) — General Schedule for Pneumocystis prophylaxis

Same-day GCA pathway

Any patient with suspected GCA and visual symptoms requires:

1. Same-day commencement of prednisolone 60 mg orally (or IV methylprednisolone 1 g if visual loss is occurring)
2. Same-day or next-day ophthalmology review for formal visual assessment
3. Rheumatology referral for temporal artery biopsy or ultrasound within 1–2 weeks
4. Clear safety netting — the patient should be advised to attend hospital immediately if visual symptoms worsen or new symptoms emerge before specialist review

E. Special populations

Older adults with multiple comorbidities

The typical PMR/GCA patient already carries several comorbidities — hypertension, type 2 diabetes, osteoporosis risk factors, and polypharmacy. Long-term prednisolone amplifies all of these risks simultaneously. A systematic approach to the six monitoring domains described above is more important, not less, in frailer patients. Consider geriatrician co-management when multiple organ systems are being monitored. Falls risk is significant — steroid myopathy, visual impairment, and postural hypotension from volume status fluctuations all contribute.

PMR-GCA overlap

Approximately 15–20% of PMR patients develop GCA during their disease course, most commonly in the first 1–2 years. At every follow-up visit for PMR, ask specifically about new headache, scalp tenderness, jaw pain on chewing, and visual symptoms. Any new onset of these symptoms in a patient already on prednisolone for PMR requires immediate dose escalation and urgent specialist review — the current PMR dose (typically 10–15 mg by the time of follow-up) is insufficient for GCA.

Corticosteroid-induced diabetes

Up to 20% of patients on long-term prednisolone for PMR or GCA develop steroid-induced hyperglycaemia requiring treatment. Post-prandial glucose elevation (particularly mid-morning) is characteristic of intermediate-acting prednisolone taken in the morning. Metformin is often first-line; insulin may be required in more severe cases. Endocrinology input is appropriate for complex cases.

ATSI populations

First Nations patients are at higher risk of type 2 diabetes and cardiovascular disease at baseline — making steroid-related metabolic side effects a higher priority concern. The 715 Health Assessment provides an appropriate framework. Closing the Gap PBS co-payment assistance reduces cost barriers to ongoing prescriptions including bisphosphonates.

When to escalate

Same-day rheumatology or ED referral: any suspected GCA with visual symptoms, jaw claudication, or diplopia — start prednisolone 60 mg immediately and arrange same-day ophthalmology.

Urgent rheumatology referral (within 1 week): new diagnosis GCA for temporal artery biopsy or ultrasound; suspected GCA with uncertain diagnosis after starting treatment; PMR failing to respond to prednisolone within 1 week.

Routine rheumatology referral: relapsing PMR requiring steroid-sparing therapy; consideration of tocilizumab for relapsing GCA; complex bone health decisions; patients in whom steroid side effects are prominent and dose reduction is proving difficult.

Ophthalmology referral: all new GCA diagnoses for baseline visual assessment; any visual symptom change; annual review for cataract and glaucoma in long-term steroid users.

What this article is and is not

This is general health information drawing on eTG, AMH, RACGP, NPS MedicineWise, and the BSR 2020 guidelines for PMR and GCA. It is not personal medical advice and does not create a doctor–patient relationship. Individual treatment decisions — including prednisolone dosing, steroid-sparing agents, bone protection prescribing, and referral pathways — are made with your GP and rheumatologist based on your specific clinical circumstances.

For AU consumer resources: HealthDirect — Polymyalgia rheumatica, Better Health Channel — Polymyalgia rheumatica, Arthritis Australia, Osteoporosis Australia.

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Sources cited

1. RACGP — Polymyalgia rheumatica and GCA resources
2. Therapeutic Guidelines (eTG) — PMR / Giant cell arteritis
3. Australian Medicines Handbook (AMH)
4. NPS MedicineWise — Corticosteroids in rheumatic disease
5. Arthritis Australia
6. Osteoporosis Australia
7. HealthDirect — Polymyalgia rheumatica
8. Better Health Channel — Polymyalgia rheumatica
9. BSR/BHPR 2020 — Polymyalgia rheumatica guidelines
10. BSR 2020 — Giant cell arteritis management guidelines
11. 2015 ACR/EULAR Provisional Classification Criteria for PMR (Dasgupta et al.)
12. Stone JH et al. GiACTA trial — tocilizumab for GCA (NEJM 2017)