Arthritis & Rheumatism, Volume 62,
November 2010 Abstract Supplement
Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Atlanta, Georgia November 6-11, 2010.
Interstitial Lung Disease in Rheumatoid Arthritis: Effect on Physical Function, Disability, Mental Health and Survival over a 10-Year Period.
Rincon2, Inmaculada Del, Restrepo3, Jose Felix, Sahai2, Mrisa, Battafarano1, Daniel F., Zuniga-Montes2, L. Ricardo, Escalante2, Agustin
Interstitial lung disease (ILD) is a serious complication of rheumatoid arthritis (RA), for which there are few therapeutic options. Moreover, information about how ILD affects the outcome of RA patients is limited. We examined the effect of ILD on physical function, disability, mental health and survival in a cohort of RA patients.
Patients and Methods:
We studied patients with RA from rheumatology clinics. At the time of recruitment and yearly thereafter, medical records were reviewed thoroughly. ILD was diagnosed clinically using X-rays, CT scans, MRIs or biopsies of the lungs. At each yearly study visit, we performed tender, swollen and deformed joint counts, and measured the erythrocyte sedimentation rate (ESR). Patients also completed the SF36 questionnaire, the Center for Epidemiological Studies Depression (CESD) scale, timed tests of walking velocity over 50-feet and shirt button fastening, and a test of grip strength. We followed patients until they died, reached a censoring date, or were lost to follow-up. We compared outcome between patients with and without ILD using generalized estimating equations (GEE), adjusting for age, gender, follow-up time, the joint counts and ESR. To study the influence of ILD on survival, we plotted Kaplan Meier curves and used Cox proportional hazards to adjust for potential confounders.
We studied 779 RA patients. Sixty nine of them (8.8%) had ILD, 147 (18.9%) had other pulmonary diagnoses, and 563 patients were free of lung diseases. Mean (95% CI) of the outcome measures in patients with ILD and patients free of lung disease, adjusted for demographics, joint findings and ESR are shown in the table.
|Velocity (ft/min)||Buttons/ minute||Grip (lbs)||Physical Function (SF36)||CESD|
|ILD||178 (162, 194)||7 (6, 8)||13 (11, 14)||55 (51, 58)||15 (14, 16)|
|No Lung Dz.||204 (199, 209)||8 (7, 8)||15 (14, 16)||60 (59, 61)||16 (14, 18)|
Median observation time was 10.3 years per patient. Among ILD patients, 48 deaths occurred in 482 patient-years (9.9 deaths per 100); in patients free of lung disease, 113 deaths occurred in 5,444 person-years (2.1 per 100), hazard ratio 4.92 (3.51, 6.92). Mortality remained elevated in ILD patients, HR 3.14 (2.04, 4.85), even after adjusting for age, sex, joint findings and ESR.
We have provided detailed estimates of the influence of ILD on multiple aspects of RA outcome. ILD had a significant, independent negative impact on the physical function, disability and survival of patients with RA, but not on measures of mental health. A better understanding of the causes and pathogenesis of ILD in RA is needed to find ways to prevent and treat this complication.
To cite this abstract, please use the following information:
Rincon, Inmaculada Del, Restrepo, Jose Felix, Sahai, Mrisa, Battafarano, Daniel F., Zuniga-Montes, L. Ricardo, Escalante, Agustin; Interstitial Lung Disease in Rheumatoid Arthritis: Effect on Physical Function, Disability, Mental Health and Survival over a 10-Year Period. [abstract]. Arthritis Rheum 2010;62 Suppl 10 :1044