To investigate the prevalence and predictors of sustained remission (SR) in an unselected Chinese rheumatoid arthritis (RA) population.
Medical records of RA patients from 2009 to 2016 were retrospectively reviewed. Clinical remission was defined according to Disease Activity Score in 28 joints using erythrocyte sedimentation rate (DAS28-ESR), Clinical Disease Activity Index (CDAI), Simplified Disease Activity Index (SDAI), and Boolean criteria. Remission persisting for at least 6 months was regarded as SR (6-month SR). Kaplan-Meier method and Cox regression analyses were performed to plot cumulative possibility of achieving 6-month SR and to identify predictors.
Seven hundred and seventy-nine patients contributing 7958 clinic visits were included. During the follow-up period, nearly half of patients achieved 6-month SR according to DAS28-ESR (51.6%), CDAI (45.6%), SDAI (44.0%), as well as Boolean definitions (42.4%). Median time periods to 6-month SR were respectively 20.5, 28.7, 30.6, and 32.9 months based on the above criteria. Specifically, 29.4% to 41.2% of patients achieved 6-month SR at least once in the first year of follow-up, depending on instruments. Multivariate Cox regression indicated that increasing age, longer disease duration, higher baseline disease activity were independently correlated with reduced possibility of 6-month SR assessed by nearly all definitions. Conversely, male, early RA, disease-modifying antirheumatic drug-naïve and lower disease activity scores in remission measured by corresponding criteria positively contributed to SR. Importantly, treat-to-target (T2T) adherence therapy and shorter time to remission were identified as stable determinants of SR across all definitions.
Achieving 6-month SR was not uncommon in daily practice. Male, early RA, treatment-naïve, T2T application, shorter time to remission, and lower disease activity scores in remission increased the occurrence of SR, while increasing age, longer disease duration, and higher baseline disease activity reduced the chance of remission sustainability.