• 1
    Adams PF, Hendershot GE, Marano MA. Current estimates from the National Health Interview Survey, 1996. National Center for Health Statistics; 1999. Vital Health Stat 10(200).
  • 2
    Shbeeb M, Uramoto KM, Gibson LE, O'Fallon WM, Gabriel SE. The epidemiology of psoriatic arthritis in Olmsted County, Minnesota, USA, 1982-1991. J Rheumatol 2000; 27: 124750.
  • 3
    Leonard DG, O'Duffy JD, Rogers RS. Prospective analysis of psoriatic arthritis in patients hospitalized for psoriasis. Mayo Clin Proc 1978; 53: 5118.
  • 4
    Salonen SH. The EUROPSO psoriasis patient study: treatment history and satisfaction reported by 17,990 members of European psoriasis patient associations. Proceedings of the Spring Symposium of the European Academy of Dermatology and Venereology. Malta; 2003.
  • 5
    Gelfand JM, Gladman, DD, Mease, P, Smith, N, Margolis, DJ, Nijsten T, et al. Epidemiology of psoriatic arthritis in the United States population. J Am Acad Dermatol. In press.
  • 6
    Boumpas DT, Illei GG, Tassiulas IO. Psoriatic arthritis. In: KlippelJH, editor. Primer on the rheumatic diseases. 12th ed. Atlanta: The Arthritis Foundation; 2001. p. 2337.
  • 7
    Gladman DD, Stafford-Brady F, Chang CH, Lewandowski K, Russell ML. Longitudinal study of clinical and radiological progression in psoriatic arthritis. J Rheumatol 1990; 17: 80912.
  • 8
    Gladman DD, Shuckett R, Russell ML, Thorne JC, Schachter RK. Psoriatic arthritis: an analysis of 220 patients. Q J Med 1987; 62: 12741.
  • 9
    Javitz HS, Ward MM, Farber E, Nail L, Vallow SG. The direct cost of care for psoriasis and psoriatic arthritis in the United States. J Am Acad Dermatol 2002; 46: 85060.
  • 10
    Jones G, Crotty M, Brooks P. Interventions for treating psoriatic arthritis. Cochrane Database Syst Rev (CD000212); 2000.
  • 11
    Kaltwasser JP, Nash P, Gladman D, Rosen CF, Behrens F, Jones P, et al. Efficacy and safety of leflunomide in the treatment of psoriatic arthritis and psoriasis: a multinational, double-blind, randomized, placebo-controlled clinical trial. Arthritis Rheum 2004; 50: 193950.
  • 12
    Partsch G, Steiner G, Leeb BF, Dunky A, Broll H, Smolen JS. Highly increased levels of tumor necrosis factor-α and other proinflammatory cytokines in psoriatic arthritis synovial fluid. J Rheumatol 1997; 24: 51823.
  • 13
    Ettehadi P, Greaves MW, Wallach D, Aderka D, Camp RD. Elevated tumor necrosis factor-α biological activity in psoriatic skin lesions. Clin Exp Immunol 1994; 96: 14651.
  • 14
    Oppenheim JJ, Ruscetti FW. Cytokines. In: StitesDP, TerrAI, ParslowTG, editors. Medical immunology. 9th ed. Stamford (CT): Prentice-Hall International, Appleton & Lange; 1999. p. 14968.
  • 15
    Moldenhauer A, Nociari M, Lam G, Salama A, Rafii S, Moore MA. Tumor necrosis factor α-stimulated endothelium: an inducer of dendritic cell development from hematopoietic progenitors and myeloid leukemic cells. Stem Cells 2004; 22: 14457.
  • 16
    Lam J, Takeshita S, Barker JE, Kanagawa O, Ross FP, Teitelbaum SL. TNF-α induces osteoclastogenesis by direct stimulation of macrophages exposed to permissive levels of RANK ligand. J Clin Invest 2000; 106: 14818.
  • 17
    Unemori EN, Hibbs MS, Amento EP. Constitutive expression of a 92-kD gelatinase (type V collagenase) by rheumatoid synovial fibroblasts and its induction in normal human fibroblasts by inflammatory cytokines. J Clin Invest 1991; 88: 165662.
  • 18
    Mease PJ, Goffe BS, Metz J, VanderStoep A, Finck B, Burge DJ. Etanercept in the treatment of psoriatic arthritis and psoriasis: a randomised trial. Lancet 2000; 356: 38590.
  • 19
    Krueger G, Callis K. Potential of tumor necrosis factor inhibitors in psoriasis and psoriatic arthritis. Arch Dermatol 2004; 140: 21825.
  • 20
    Mease PJ, Kivitz AJ, Burch FX, Siegel EL, Cohen SB, Ory P, et al. Etanercept treatment of psoriatic arthritis: safety, efficacy, and effect on disease progression. Arthritis Rheum 2004; 50: 226472.
  • 21
    Antoni CE, Kavanaugh A, Kirkham B, Tutuncu Z, Burmester GR, Schneider U, et al. Sustained benefits of infliximab therapy for dermatologic and articular manifestations of psoriatic arthritis: results from the Infliximab Multinational Psoriatic Arthritis Controlled Trial. Arthritis Rheum 2005; 52: 122736.
  • 22
    Kavanaugh A, Krueger GG, de Vlam K, Birbara C, Beutler A, Guzzo C, et al. Infliximab significantly improves joint and skin involvement in psoriatic arthritis to a substantial extent and irrespective of baseline joint involvement or MTX use: analysis of clinical response from the IMPACT2 trial [abstract]. Arthritis Rheum 2004; 50 Suppl 9: S617.
  • 23
    Mease P. TNFα therapy in psoriatic arthritis and psoriasis. Ann Rheum Dis 2004; 63: 7558.
  • 24
    Weinblatt ME, Keystone EC, Furst DE, Moreland LW, Weisman MH, Birbara CA, et al. Adalimumab, a fully human anti–tumor necrosis factor α monoclonal antibody for the treatment of rheumatoid arthritis in patients taking concomitant methotrexate: the ARMADA trial. Arthritis Rheum 2003; 48: 3545.
  • 25
    Keystone EC, Kavanaugh AF, Sharp JT, Tannenbaum H, Hua Y, Teoh LS, et al. Radiographic, clinical, and functional outcomes of treatment with adalimumab (a human anti–tumor necrosis factor monoclonal antibody) in patients with active rheumatoid arthritis receiving concomitant methotrexate therapy: a randomized, placebo-controlled, 52-week trial. Arthritis Rheum 2004; 50: 140011.
  • 26
    Van de Putte LB, Atkins C, Malaise M, Sany J, Russell AS, van Riel PL, et al. Efficacy and safety of adalimumab as monotherapy in patients with rheumatoid arthritis for whom previous disease modifying antirheumatic drug treatment has failed. Ann Rheum Dis 2004; 63: 50816.
  • 27
    Felson DT, Anderson JJ, Boers M, Bombardier C, Furst D, Goldsmith C, et al. American College of Rheumatology preliminary definition of improvement in rheumatoid arthritis. Arthritis Rheum 1995; 38: 72735.
  • 28
    Sharp JT, Young DY, Bluhm GB, Brook A, Brower AC, Corbett M, et al. How many joints in the hands and wrists should be included in a score of radiologic abnormalities used to assess rheumatoid arthritis? Arthritis Rheum 1985; 28: 132635.
  • 29
    Clegg DO, Reda DJ, Mejias E, Cannon GW, Weisman MH, Taylor T, et al. Comparison of sulfasalazine and placebo in the treatment of psoriatic arthritis: a Department of Veterans Affairs cooperative study. Arthritis Rheum 1996; 39: 201320.
  • 30
    Fries JF, Spitz PW, Young DY. The dimensions of health outcomes: the Health Assessment Questionnaire, disability and pain scales. J Rheumatol 1982; 9: 78993.
  • 31
    Ware JE Jr, Sherbourne CD. The MOS 36-item short-form health survey (SF-36). I. Conceptual framework and item selection. Med Care 1992; 30: 47383.
  • 32
    Cella D, Webster K. Linking outcomes management to quality-of-life measurement. Oncology 1997; 11: 2325.
  • 33
    Fredriksson T, Pettersson U. Severe psoriasis: oral therapy with a new retinoid. Dermatologica 1978; 157: 23844.
  • 34
    Ellis CN, Krueger GG. Treatment of chronic plaque psoriasis by selective targeting of memory effector T lymphocytes. N Engl J Med 2001; 345: 24855.
  • 35
    Finlay AY, Khan GK. Dermatology life quality index: a simple practical measure for routine clinical use. Clin Exp Dermatol 1994; 19: 2106.
  • 36
    Kosinski M, Zhao SZ, Dedhiya S, Osterhaus JT, Ware JE Jr. Determining minimally important changes in generic and disease-specific health-related quality of life questionnaires in clinical trials of rheumatoid arthritis. Arthritis Rheum 2000; 43: 147887.
  • 37
    Wollina U, Stander K, Barta U. Toxicity of methotrexate treatment in psoriasis and psoriatic arthritis: short- and long-term toxicity in 104 patients. Clin Rheumatol 2001; 20: 40610.
  • 38
    Whiting-O'Keefe QE, Fye KH, Sack KD. Methotrexate and histologic hepatic abnormalities: a meta-analysis. Am J Med 1991; 90: 7116.
  • 39
    Farr M, Kitas GD, Waterhouse L, Jubb R, Felix-Davies D, Bacon PA. Sulphasalazine in psoriatic arthritis: a double-blind placebo-controlled study. Br J Rheumatol 1990; 29: 469.
  • 40
    Ritchlin C, Anandarajaha A, Totterman S, Shao T, Kemshetti S, Badger W, et al. Preliminary data from a study of adalimumab in the treatment of psoriatic arthritis [abstract]. Ann Rheum Dis 2004; 63 Suppl 1: 403.
  • 41
    Menter MA, Gordon KB, Leonardi C, Heffernan MP, Chen DM. Adalimumab efficacy and safety results in patients with moderate to severe chronic plaque psoriasis with and without PsA [abstract]. Arthritis Rheum 2004; 50 Suppl 9: S6112.
  • 42
    Leonardi CL, Powers JL, Matheson RT, Goffe BS, Zitnik R, Wang A, et al. Etanercept as monotherapy in patients with psoriasis. N Engl J Med 2003; 349: 201422.
  • 43
    Targan SR, Hanauer SB, van Deventer SJ, Mayer L, Present DH, Braakman T, et al, and the Crohn's Disease cA 2 Study Group. A short-term study of chimeric monoclonal antibody cA2 to tumor necrosis factor α for Crohn's disease. N Engl J Med 1997; 337: 102935.
  • 44
    Sandborn WJ, Hanauer SB, Katz S, Safdi M, Wolf DG, Baerg RD, et al. Etanercept for active Crohn's disease: a randomized, double-blind, placebo-controlled trial. Gastroenterology 2001; 121: 108894.
  • 45
    Hanauer S, Lukas M, Macintosh D, Rutgeerts P, Sandborn W, Pollack P. A randomized, double-blind, placebo-controlled trial of the human anti-TNF-α monoclonal antibody adalimumab for the induction of remission in patients with moderate to severely active Crohn's disease. Gastroenterology 2004; 127: 332.
  • 46
    Strand V, Sharp JT. Radiographic data from recent randomized controlled trials in rheumatoid arthritis: what have we learned? [editorial]. Arthritis Rheum 2003; 48: 2134.
  • 47
    Keystone EC, Kavanaugh AF, Sharp JT, Spencer-Green GT, Perez JL, Sasso EH. Radiographic inhibition of structural damage sustained in patients with long-standing rheumatoid arthritis following 3 years of treatment with adalimumab (HUMIRA) plus methotrexate [abstract]. Arthritis Rheum 2004; 50 Suppl 9: S189.
  • 48
    Breedveld FC, Kavanaugh AF, Cohen SB, Pavelka K, van Vollenhoven R, Perez JL, et al. Early treatment of rheumatoid arthritis (RA) with adalimumab (HUMIRA) plus methotrexate vs. adalimumab alone or methotrexate alone: the Premier study [abstract]. Arthritis Rheum 2004; 50: 40967.
  • 49
    Klareskog L, van der Heijde D, de Jager JP, Gough A, Kalden J, Malaise M, et al. Therapeutic effect of the combination of etanercept and methotrexate compared with each treatment alone in patients with rheumatoid arthritis: double-blind randomised controlled trial. Lancet 2004; 363: 67581.
  • 50
    Cuellar ML, Espinoza LR. Methotrexate use in psoriasis and psoriatic arthritis. Rheum Dis Clin North Am 1997; 23: 797809.
  • 51
    Feletar M, Brockbank JE, Schentag CT, Lapp V, Gladman DD. Treatment of refractory psoriatic arthritis with infliximab: a 12 month observational study of 16 patients. Ann Rheum Dis 2004; 63: 15661.
  • 52
    Langley R, Leonardi C, Toth D, Hoffman R. Long-term safety and efficacy of adalimumab in the treatment of moderate to severe chronic plaque psoriasis [abstract]. J Am Acad Dermatol 2005; 52 Suppl 3: 2.