Treatment of Psoriatic Arthritis and Rheumatoid Arthritis with Disease Modifying Drugs — Comparison of Drugs and Adverse Reactions

PHILIP S. HELLIWELL and WILLIAM J. TAYLOR for the CASPAR Study Group

ABSTRACT.

Objective. Rheumatoid arthritis (RA) and psoriatic arthritis (PsA) are chronic inflammatory diseases of the musculoskeletal system. Although it seems likely that these conditions have a different pathogenesis, the drugs used to treat them are the same. Our study used a cross-sectional clinical database to compare drug use and side-effect profile in these 2 diseases.

Methods. The CASPAR study collected data on 588 patients with PsA and 536 controls, 70% of whom had RA. Data on disease modifying drug treatments used over the whole illness were recorded, together with their outcomes, including adverse events, for RA and PsA.

Results. For both diseases methotrexate (MTX) was the most frequently used disease modifying drug (39% of patients with PsA, 30% with RA), with over 70% of patients in both diseases still taking the drug. Other drugs were used with the following frequencies in PsA and RA, respectively: sulfasalazine 22%/13%, gold salts 7%/11%, antimalarial drugs 5%/14%, corticosteroids 10%/17%, and anti-tumor necrosis factor (TNF) drugs 6%/5%. Compared to RA, cyclosporine and anti-TNF agents were less likely to be ineffective in PsA. Compared to RA, subjects with PsA were less likely to be taking MTX and more likely to be taking anti-TNF agents. Hepatotoxicity with MTX was more common in PsA, and pulmonary toxicity with MTX was found more often in RA.

Conclusion. These data provide insight into prescribing patterns of disease modifying drugs in RA and PsA in a large international cohort, together with the differential adverse events of these drugs between these diseases. (First Release Jan 15 2008; J Rheumatol 2008;35:472-6)

Key Indexing Terms:

PSORIATIC ARTHRITIS
RHEUMATOID ARTHRITIS
ADVERSE EFFECTS
DISEASE MODIFYING DRUGS
TREATMENT
ANTI-TUMOR NECROSIS FACTOR DRUGS

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From the Academic Unit of Musculoskeletal and Rehabilitation Medicine, University of Leeds, Leeds, UK; and the Rehabilitation Teaching and Research Unit, Department of Medicine, Wellington School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand.

Supported by the European League Against Rheumatism, Barnsley District NHS Trust, Groote Schuur Hospital, Cape Town, South Africa; Department of Medical Sciences, University Hospital, Uppsala, Sweden; Krembil Foundation; St. Vincent's University Hospital Radiology Department, Dublin, Ireland; Inkosi Albert Luthuli Central Hospital, Durban, South Africa; El Ayachi Hospital, Salé, Morocco; National Psoriasis Foundation, USA; The Foundation for Scientific Research of the Belgian Society of Rheumatology; and Arthritis New Zealand. Dr. Taylor was supported by a Dorothy Eden Fellowship, Arthritis New Zealand.

P.S. Helliwell, MD, PhD, Academic Unit of Musculoskeletal and Rehabilitation Medicine, University of Leeds; W.J. Taylor, MBChB, PhD, FRACP, FAFRM, Rehabilitation Teaching and Research Unit, Department of Medicine, Wellington School of Medicine and Health Sciences, University of Otago.

Address reprint requests to Dr. P. Helliwell, Academic Unit of Musculoskeletal and Rehabilitation Medicine, University of Leeds, 36 Clarendon Road, Leeds LS2 9NZ, UK. E-mail: p.helliwell@leeds.ac.uk

Accepted for publication October 24, 2007.

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