Anti-carbamylated protein antibodies positivity and disease activity in Hispanic patients with established rheumatoid arthritis: An observational study.

OBJECTIVES: We aimed to determine the prevalence of anti-carbamylated protein (anti-CarP) antibodies in Mexican Hispanics with established rheumatoid arthritis (RA) and to assess their relationship with disease activity. METHODS: A cohort study was conducted in 278 patients with established RA during an 18-month follow-up. We measured IgG/IgM/IgA rheumatoid factor (RF), IgG anticitrullinated protein antibodies (ACPA) and IgG/IgM/IgA anti-CarP antibodies using enzyme-linked immunosorbent assay (ELISA). For disease activity, we performed the 28-joint disease activity score with erythrocyte sedimentation rate (DAS28-ESR). Repeated measures one-way ANOVA was used to test the association between anti-CarP IgG antibody status and longitudinal DAS28-ESR scores. Patients were evaluated at baseline and at 6, 12, and 18 months during follow-up. RESULTS: Anti-CarP IgG antibodies were positive in 47.8% of patients and, accounting for all isotypes, in 9.5% of patients with negative RF and ACPA. Triple antibody positivity was present in 42.6% of patients in our sample. Anti-CarP IgG antibody positivity did not show statistically significant differences in mean DAS28-ESR when compared to anti-CarP IgG antibody negative patients at baseline, 6, 12 or 18 months. CONCLUSION: Anti-CarP IgG antibodies are not associated to a higher disease activity in Hispanic patients with established RA. Our findings suggest that the clinical value of measuring anti-CarP antibodies in RA diminishes over time.

The Impact of Osteoarthritis on the Functioning and Health Status of a Low-Income Population: An Example of a Disability Paradox.

OBJECTIVE: The aim of this study was to measure the impact of osteoarthritis on the functioning and health status of individuals living in a low-income urban community in Mexico. METHODS: We conducted a cross-sectional, community-based study from December 2014 to November 2015, using the Community Oriented Program for Control of Rheumatic Diseases methodology to identify cases of musculoskeletal disease in a sample of adults older than 18 years in Pueblo Nuevo, Apodaca, Mexico. Two rheumatologists confirmed all cases of osteoarthritis (OA) using predefined criteria. Functioning was evaluated through (a) self-report of difficulty doing personal care, work, and leisure activities; (b) the modified Stanford Health Assessment Questionnaire-Disability Index; and (c) the Timed Up and Go test. Health status was evaluated using the EuroQoL 5 Dimensions. Statistical analyses were performed using χ tests and logistic regression models. RESULTS: Four hundred thirty-nine individuals with a mean age of 45.2 years were included, and 83 cases of OA were confirmed. The presence of OA was not significantly associated with having difficulties to do personal care, work, or leisure activities, but it was significantly associated with a higher Health Assessment Questionnaire-Disability Index score, longer time to complete the Timed Up and Go, and lower health status. CONCLUSIONS: Osteoarthritis is associated with having higher disability and worse health status in the community studied. A disability paradox was detected as some individuals perceived disability for doing standard activities but did not present disability performing their real-life activities. This underlies the importance of addressing the mental dimension during the management of this population.