What are the treatment options for psoriasis arthritis?

Treatment of Psoriatic Arthritis

Initial Treatment Strategy

For mild peripheral arthritis, start with NSAIDs as first-line therapy for symptom control, and rapidly escalate to DMARDs (sulfasalazine or leflunomide preferred) for moderate to severe disease, with TNF inhibitors reserved for inadequate response to at least one DMARD trial. 1

Mild Disease Approach

• NSAIDs provide symptomatic relief and should be initiated for musculoskeletal symptoms, though cardiovascular and gastrointestinal risks must be considered 2
• Intra-articular glucocorticoid injections are recommended for persistently inflamed joints, avoiding injection through psoriatic plaques 1, 2
• Physical therapy should be initiated concurrently with NSAIDs 2
• Critical caveat: NSAIDs provide symptomatic relief only and do not prevent structural joint damage 1

Moderate to Severe Disease: DMARD Selection

Initiate DMARDs rapidly when patients have five or more actively inflamed joints, elevated acute phase reactants (ESR/CRP), radiographic damage progression, loss of function, or diminished quality of life. 3, 2

Preferred DMARDs (Level A Evidence):

• Sulfasalazine - first-line DMARD with Level A evidence for peripheral arthritis 1, 4
• Leflunomide - first-line DMARD with Level A evidence for peripheral arthritis 1, 4

Alternative DMARDs:

• Methotrexate (15-25 mg weekly with folic acid) - Level B evidence, preferred when significant skin involvement coexists with peripheral arthritis 1, 4
• Cyclosporine - Level B evidence, but should be limited to <12 consecutive months due to cumulative nephrotoxicity 1, 4

Important contraindication: Do not use methotrexate as first-line in patients with concomitant diabetes due to higher risk of fatty liver disease and hepatotoxicity 1

TNF Inhibitor Therapy

TNF inhibitors (adalimumab, etanercept, infliximab) should be initiated for inadequate response to at least one DMARD after an adequate trial, or immediately for patients with poor prognostic factors. 1, 2

FDA-Approved TNF Inhibitors for Psoriatic Arthritis:

• Infliximab: 5 mg/kg IV at 0,2, and 6 weeks, then every 8 weeks 5
• Adalimumab: reduces signs and symptoms of active arthritis, inhibits structural damage progression 5
• Etanercept: efficacy may be dose-dependent; higher doses (up to 100 mg weekly) may be needed for optimal benefit, particularly in patients with high BMI 3

All three TNF inhibitors are equally effective for peripheral arthritis and inhibiting radiographic progression - no head-to-head trials demonstrate superiority of one over another 1, 2

Poor Prognostic Factors Warranting Earlier TNF Inhibitor Use:

• Polyarticular disease (versus monoarticular) 3
• Elevated ESR or CRP 3
• Previous treatment failures 3
• Existing joint damage on radiographs or clinical examination 3
• Diminished quality of life (SF-36, DLQI, or PsAQoL) 3

Special Manifestations

Enthesitis Treatment Algorithm:

• Mild: NSAIDs, physical therapy, and local corticosteroids 2
• Moderate: DMARDs 2
• Severe: TNF inhibitors (infliximab and etanercept have Level A evidence) 2

Dactylitis Treatment:

• Mild: NSAIDs and local measures 1
• Resistant: DMARDs 1
• Severe/refractory: TNF inhibitors 1

Axial Disease:

• Start with NSAIDs and physiotherapy 1
• Progress to TNF inhibitors if inadequate response 1
• Consider IL-17 inhibitors if significant skin involvement 1

Skin Disease Management

For patients with moderate to severe skin disease (>5% body surface area or vulnerable areas), consider methotrexate, phototherapy, or TNF inhibitors as first-line systemic therapy. 3, 6

• Topical therapies (corticosteroids, vitamin D analogs) are appropriate for mild skin disease (<5% BSA) 6
• TNF inhibitors effectively treat both skin and joint manifestations simultaneously 3, 7
• Avoid systemic corticosteroids as monotherapy - can cause severe psoriasis flare during or after taper 3, 6

Critical Safety Monitoring

Before Initiating TNF Inhibitors:

• Test for latent tuberculosis - if positive, start TB treatment before initiating TNF inhibitor 5
• Test for hepatitis B virus - monitor HBV carriers during and several months after therapy 5
• Screen for history of serious infections, heart failure, demyelinating disease 5

During Treatment:

• Monitor all patients for active TB during treatment, even if initial test negative 5
• Watch for serious infections - discontinue TNF inhibitor if serious infection develops 5
• Monitor liver enzymes - stop therapy if jaundice or marked elevations occur 5
• Boxed warning: Increased risk of lymphoma and other malignancies, particularly hepatosplenic T-cell lymphoma in young males receiving concomitant azathioprine or 6-mercaptopurine 5

Medications to Avoid

• Gold salts, chloroquine, and hydroxychloroquine are not recommended for PsA 3
• Systemic corticosteroids should not be used chronically due to risk of post-steroid psoriasis flare 3
• Drugs that may worsen psoriasis: beta-blockers, NSAIDs (paradoxically), lithium, chloroquine, alcohol 6

Treatment Failure Definition

A patient is considered a treatment failure when, despite therapy for an appropriate duration at adequate dose, they fail to demonstrate acceptable clinical improvement, or show evidence of radiographic progression 3