Tužil J, Mlčoch T, Závada J, et al. - Time in remission (TIR) affords a valid predictor for the outcomes of rheumatoid arthritis (RA), and represents an intuitive means of estimating unobserved disease activity (DA) between scheduled visits, its calculation only needs two consecutive DA values (https://www.medevio.cz/tir-calculator/).

• Patients from the Czech ATTRA-RA registry underwent TIR calculation using linear interpolation of the DAS28-ESR ascertained at outpatient visits.

• Since 2010, a total of 2,618 RA patients initiated anti-TNF treatment and were observed until 2020 or until treatment cessation.

• No remission (TIR = 0) in 56% of patients, sustained remission (TIR = 1) in 22%, and point remissions with 0

• Follow-up showed growth of mean TIR, and a correlation of mean TIR with DAS28-CRP, SDAI, HAQ, Patient (PGA), and physician global assessment (PhGA) was evident.

• Compared with point or sustained remission, better prediction of remission (SDAI ≤ 3.3) and non-disability (HAQ < 0.5) at 13 and 19 months was provided by TIR at 3 and 6 months.