The relationship between disease activity and radiologic progression in patients with rheumatoid arthritis: a longitudinal analysis.

OBJECTIVE Radiologic progression in rheumatoid arthritis (RA) is considered the consequence of persistent inflammatory activity. To determine whether a change in disease activity is related to a change in radiologic progression in individual patients, we investigated the longitudinal relationship between inflammatory disease activity and subsequent radiologic progression. METHODS The databases of the University Medical Center Nijmegen (UMCN) cohort and the Maastricht Combination Therapy in RA (COBRA) followup study cohort were analyzed. The UMCN cohort included 185 patients with early RA who were followed up for up to 9 years. Patients were assessed every 3 months for disease activity and every 3 years for radiologic damage. The COBRA cohort included 152 patients with early RA who were followed up for up to 6 years. Patients were assessed at least every year for disease activity and every 12 months for radiologic damage. Disease activity was assessed with the Disease Activity Score (DAS) (original DAS in the UMCN cohort, DAS28 in the COBRA cohort). Radiologic damage was measured by the Sharp/van der Heijde score in both cohorts. Data were analyzed with longitudinal regression analysis (generalized estimating equations [GEE]), using autoregression for longitudinal associations and radiologic damage as the dependent variable. Time, time(2) baseline predictors for radiologic progression and their interactions with time, as well as DAS/DAS28 (actual values or interval means and interval SDs of the means) were subsequently modeled as explanatory variables. RESULTS Data analyzed by GEE showed a decrease in radiologic progression over time (regression coefficient for time(2) -1.0 [95% confidence interval -1.4, -0.6] in the UMCN cohort and -0.4 [95% confidence interval -0.8, 0.0] in the COBRA cohort). After adjustment for time effects and baseline predictors of radiologic progression and their interactions with time, a positive longitudinal relationship was indicated by autoregressive GEE between the mean interval DAS and radiologic progression in the UMCN cohort (regression coefficient 5.4 [95% confidence interval 2.1, 8.6]), and between the DAS28 and radiologic progression in the COBRA cohort (regression coefficient 1.4 [95% confidence interval 0.8, 2.0]). In the UMCN cohort, the SD of the mean interval DAS was independently longitudinally related to the radiologic progression over the same periods (regression coefficient 20.2 [95% confidence interval 7.2, 33.3]). In both cohorts, the longitudinal relationships between (fluctuations in) disease activity and radiologic progression were found selectively in rheumatoid factor (RF)-positive patients. CONCLUSION Radiologic progression is not linear in individual patients. Fluctuations in disease activity are directly related to changes in radiologic progression, which supports the hypothesis that disease activity causes radiologic damage. This relationship might only exist in RF-positive patients.

[1]  E C Coles,et al.  Relationship between time-integrated C-reactive protein levels and radiologic progression in patients with rheumatoid arthritis. , 2000, Arthritis and rheumatism.

[2]  P. Jones,et al.  Patterns of radiological progression in early rheumatoid arthritis: results of an 8 year prospective study. , 1998, The Journal of rheumatology.

[3]  S. van der Linden,et al.  Reading radiographs in chronological order, in pairs or as single films has important implications for the discriminative power of rheumatoid arthritis clinical trials. , 1999, Rheumatology.

[4]  P. Lipsky,et al.  Infliximab (chimeric anti-tumour necrosis factor α monoclonal antibody) versus placebo in rheumatoid arthritis patients receiving concomitant methotrexate: a randomised phase III trial , 1999, The Lancet.

[5]  P. Tugwell,et al.  World Health Organization and International League of Associations for Rheumatology core endpoints for symptom modifying antirheumatic drugs in rheumatoid arthritis clinical trials. , 1994, The Journal of rheumatology. Supplement.

[6]  L. Truedsson,et al.  Disease activity and joint damage progression in early rheumatoid arthritis: relation to IgG, IgA, and IgM rheumatoid factor. , 1990, Annals of the rheumatic diseases.

[7]  D A Bloch,et al.  The progression of erosion and joint space narrowing scores in rheumatoid arthritis during the first twenty-five years of disease. , 1991, Arthritis and rheumatism.

[8]  M. V. van Leeuwen,et al.  The acute-phase response in relation to radiographic progression in early rheumatoid arthritis: a prospective study during the first three years of the disease. , 1993, British journal of rheumatology.

[9]  A. Zwinderman,et al.  Radiographic damage of large joints in long-term rheumatoid arthritis and its relation to function. , 2000, Rheumatology.

[10]  D. M. van der Heijde,et al.  The course of radiologic damage during the first six years of rheumatoid arthritis. , 2000, Arthritis and rheumatism.

[11]  F. Wolfe,et al.  The level of inflammation in rheumatoid arthritis is determined early and remains stable over the longterm course of the illness. , 2001, The Journal of rheumatology.

[12]  D. M. van der Heijde,et al.  Methodological issues in radiographic scoring methods in rheumatoid arthritis. , 1999, The Journal of rheumatology.

[13]  S. van der Linden,et al.  Randomised comparison of combined step-down prednisolone, methotrexate and sulphasalazine with sulphasalazine alone in early rheumatoid arthritis , 1997, The Lancet.

[14]  K. Eberhardt,et al.  Development of radiographic damage during the first 5-6 yr of rheumatoid arthritis. A prospective follow-up study of a Swedish cohort. , 1996, British journal of rheumatology.

[15]  A. Familian,et al.  Complement activation in patients with rheumatoid arthritis mediated in part by C-reactive protein. , 2001, Arthritis and rheumatism.

[16]  M. V. van Leeuwen,et al.  Interrelationship of outcome measures and process variables in early rheumatoid arthritis. A comparison of radiologic damage, physical disability, joint counts, and acute phase reactants. , 1994, The Journal of rheumatology.

[17]  B. Dijkmans,et al.  Levels of markers of bone resorption are moderately increased in patients with inactive rheumatoid arthritis. , 2000, Rheumatology.

[18]  K Y Liang,et al.  Longitudinal data analysis for discrete and continuous outcomes. , 1986, Biometrics.

[19]  M. Leirisalo-Repo,et al.  Prognostic value of quantitative measurement of rheumatoid factor in early rheumatoid arthritis. , 1995, British journal of rheumatology.

[20]  Jos Twisk,et al.  Attrition in longitudinal studies. How to deal with missing data. , 2002, Journal of clinical epidemiology.

[21]  J. Kirwan The relationship between synovitis and erosions in rheumatoid arthritis. , 1997, British journal of rheumatology.

[22]  P. van Riel,et al.  Validation of rheumatoid arthritis improvement criteria that include simplified joint counts. , 1998, Arthritis and rheumatism.

[23]  M. A. van 't Hof,et al.  Judging disease activity in clinical practice in rheumatoid arthritis: first step in the development of a disease activity score. , 1990, Annals of the rheumatic diseases.

[24]  A. Silman,et al.  Time to first occurrence of erosions in inflammatory polyarthritis: results from a prospective community-based study. , 2001, Arthritis and rheumatism.

[25]  M. A. van 't Hof,et al.  Modified sharp method: factors influencing reproducibility and variability. , 2001, Seminars in arthritis and rheumatism.

[26]  M. V. van Leeuwen,et al.  Influence of a ceiling effect on the assessment of radiographic progression in rheumatoid arthritis during the first 6 years of disease. , 1999, The Journal of rheumatology.

[27]  M. V. van Leeuwen,et al.  Individual relationship between progression of radiological damage and the acute phase response in early rheumatoid arthritis. Towards development of a decision support system. , 1997, The Journal of rheumatology.

[28]  L. Kiemeney,et al.  The relationship between disease activity, joint destruction, and functional capacity over the course of rheumatoid arthritis. , 2001, Arthritis and rheumatism.

[29]  M. Prevoo,et al.  Modified disease activity scores that include twenty-eight-joint counts. Development and validation in a prospective longitudinal study of patients with rheumatoid arthritis. , 1995, Arthritis and rheumatism.

[30]  F. Speizer,et al.  The use of an autoregressive model for the analysis of longitudinal data in epidemiologic studies. , 1985, Statistics in medicine.

[31]  J. Twisk,et al.  Different Statistical Models to Analyze Epidemiological Observational Longitudinal Data: An Example from the Amsterdam Growth and Health Study , 1997, International journal of sports medicine.

[32]  W. Willett,et al.  Interval estimates for correlation coefficients corrected for within-person variation: implications for study design and hypothesis testing. , 1988, American journal of epidemiology.

[33]  M. Prevoo,et al.  Development and validation of the European League Against Rheumatism response criteria for rheumatoid arthritis. Comparison with the preliminary American College of Rheumatology and the World Health Organization/International League Against Rheumatism Criteria. , 1996, Arthritis and rheumatism.