Helga Radner1, Josef S Smolen, Daniel Aletaha. 1. Division of Rheumatology, Department of Internal Medicine 3, Medical University Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria. helga.radner@meduniwien.ac.at
Abstract
BACKGROUND: Physical disability is a main outcome in rheumatoid arthritis (RA) which tends to increase with comorbidities. However, the extent to which comorbidities contribute to the multifactorial process of disability has not been investigated. OBJECTIVE: To quantify the contribution of comorbidity to physical disability in patients with RA. METHODS: In a prospective cohort study, age-adjusted Charlson comorbidity index (CCI(A)), serial measurements of disease activity and functional disability (evaluated by the Health Assessment Questionnaire Disability Index, HAQ) of 380 patients with established RA seen at an outpatient clinic over 1 year (June 2007 to July 2008) were ascertained. The association between comorbidity and physical disability was assessed using analysis of variance (ANOVA) and adjusted general linear regression models. RESULTS: Four patient groups with increasing levels of comorbidity (CCI(A) 0, 1-2, 3-4 and 5-9; potential range 0-38) were defined. Mean HAQ scores were significantly different across these groups (0.67, 0.80, 1.24, 1.40, respectively; p<0.001) and also when adjusted for disease activity, gender and disease duration in the regression model (0.84, 0.88, 1.14, 1.48, respectively; p<0.001). The effects of CCI(A) on disability were similar within different strata of disease activity: namely, remission (0.26, 0.31, 0.48 and 0.88, p<0.01); low disease activity (0.83, 0.78, 0.98 and 1.36, p<0.01); and moderate to high disease activity (1.22, 1.33, 1.70 and 1.91, p<0.01), and thus were independent of disease activity. Several sensitivity analyses, including the use of the Short Form Health Survey (SF-36), confirmed these observations. CONCLUSION: Physical disability becomes worse with increasing levels of comorbidity, irrespective of disease activity.
BACKGROUND: Physical disability is a main outcome in rheumatoid arthritis (RA) which tends to increase with comorbidities. However, the extent to which comorbidities contribute to the multifactorial process of disability has not been investigated. OBJECTIVE: To quantify the contribution of comorbidity to physical disability in patients with RA. METHODS: In a prospective cohort study, age-adjusted Charlson comorbidity index (CCI(A)), serial measurements of disease activity and functional disability (evaluated by the Health Assessment Questionnaire Disability Index, HAQ) of 380 patients with established RA seen at an outpatient clinic over 1 year (June 2007 to July 2008) were ascertained. The association between comorbidity and physical disability was assessed using analysis of variance (ANOVA) and adjusted general linear regression models. RESULTS: Four patient groups with increasing levels of comorbidity (CCI(A) 0, 1-2, 3-4 and 5-9; potential range 0-38) were defined. Mean HAQ scores were significantly different across these groups (0.67, 0.80, 1.24, 1.40, respectively; p<0.001) and also when adjusted for disease activity, gender and disease duration in the regression model (0.84, 0.88, 1.14, 1.48, respectively; p<0.001). The effects of CCI(A) on disability were similar within different strata of disease activity: namely, remission (0.26, 0.31, 0.48 and 0.88, p<0.01); low disease activity (0.83, 0.78, 0.98 and 1.36, p<0.01); and moderate to high disease activity (1.22, 1.33, 1.70 and 1.91, p<0.01), and thus were independent of disease activity. Several sensitivity analyses, including the use of the Short Form Health Survey (SF-36), confirmed these observations. CONCLUSION: Physical disability becomes worse with increasing levels of comorbidity, irrespective of disease activity.
Authors: Sizheng Steven Zhao; Helga Radner; Stefan Siebert; Stephen J Duffield; Daniel Thong; David M Hughes; Robert J Moots; Daniel H Solomon; Nicola J Goodson Journal: Rheumatology (Oxford) Date: 2019-10-01 Impact factor: 7.580
Authors: William J Martin; Man Shim; Harold E Paulus; Sandeep Chaudhari; JingYuan Feng; David Elashoff; Theodore J Hahn; Veena K Ranganath Journal: J Clin Rheumatol Date: 2014-09 Impact factor: 3.517
Authors: Veena K Ranganath; Paul Maranian; David A Elashoff; Thasia Woodworth; Dinesh Khanna; Theodore Hahn; Catherine Sarkisian; Joel M Kremer; Daniel E Furst; Harold E Paulus Journal: Rheumatology (Oxford) Date: 2013-06-27 Impact factor: 7.580