What is giant cell arteritis (GCA)?

From the Guidelines

Giant cell arteritis (GCA) should be treated immediately with high-dose glucocorticoid therapy, typically 40-60 mg/day prednisone-equivalent, as recommended by the 2021 American College of Rheumatology/Vasculitis Foundation guideline 1.

Treatment Approach

The treatment approach for GCA involves initiating high-dose glucocorticoids without waiting for biopsy confirmation, as the condition can lead to vision loss if left untreated.

• The initial dose of prednisone is typically 40-60 mg daily, which is maintained for 2-4 weeks until symptoms resolve and inflammatory markers normalize.
• For patients with visual symptoms, initial treatment may include IV methylprednisolone 500-1000mg daily for 3 days.
• Tocilizumab, an IL-6 receptor antagonist, may be added as a steroid-sparing agent at 162mg subcutaneously weekly or every other week, as approved by the US Food and Drug Administration for the treatment of GCA 1.

Monitoring and Prevention

Patients require regular monitoring of symptoms, inflammatory markers (ESR, CRP), and potential steroid side effects.

• Low-dose aspirin (81mg daily) is often recommended to reduce the risk of ischemic complications.
• Calcium and vitamin D supplementation should be provided to prevent osteoporosis, a common side effect of long-term glucocorticoid use.

Importance of Prompt Treatment

GCA requires prompt treatment because the inflammation of arterial walls can lead to narrowing, reduced blood flow, and potential permanent damage to affected tissues, particularly the optic nerve.

• The 2021 American College of Rheumatology/Vasculitis Foundation guideline provides evidence-based recommendations for the evaluation and management of GCA, emphasizing the importance of prompt treatment and regular monitoring 1.

From the Research

Treatment of Giant Cell Arteritis

• The primary treatment for giant cell arteritis is corticosteroids, which remain the cornerstone of therapy 2, 3, 4, 5, 6.
• Methotrexate has been shown to be a safe alternative to corticosteroid therapy alone and is more effective in controlling the disease 2.
• The use of methotrexate can reduce the proportion of patients who experience at least one relapse and the proportion of patients who experience multiple relapses 2.
• Tocilizumab is also an approved substance for the treatment of giant cell arteritis and can be used as a GC-sparing therapy 3, 5.
• Aspirin may be beneficial in preventing cardiovascular events and is recommended during the first month of treatment or longer in case of occurrence of an ischemic complication 3, 4.
• Prevention of osteoporosis is also an important aspect of the treatment of giant cell arteritis, and patients should receive prevention with respect to usual recommendations 3.

Corticosteroid Therapy

• The initial dosage of prednisone should be chosen based on the disease severity and comorbidities to reduce drug side effects 4.
• The goal of corticosteroid therapy is to taper the dose to 15-20mg/day at 3 months, 10mg/day at 6 months, 5mg/day at 9-12 months, and withdrawal between 12 and 18 months 3.
• In cases of corticosteroid dependence or intolerance, a GC-sparing therapy should be introduced, mainly methotrexate or tocilizumab 3, 5.

GC-Sparing Therapies

• Methotrexate has a moderate corticosteroid-sparing effect but does not prevent cephalic complications, and there is no evidence of a reduced frequency of CS adverse effects with this drug 4.
• Tocilizumab has shown promising efficacy in the treatment of giant cell arteritis, but its benefit-to-risk ratio in old people is largely unknown 4, 5.
• Other GC-sparing therapies, such as hydroxychloroquine and infliximab or adalimumab, have not been shown to be effective in preventing relapses 4.