PT  - JOURNAL ARTICLE
AU  - Thomas R.P. Taylor
AU  - James Galloway
AU  - Rebecca Davies
AU  - Kimme Hyrich
AU  - Ruth Dobson
TI  - Demyelinating Events Following Initiation of Anti-TNFα Therapy in the British Society for Rheumatology Biologics Registry in Rheumatoid Arthritis
AID  - 10.1212/NXI.0000000000000992
DP  - 2021 May 01
TA  - Neurology - Neuroimmunology Neuroinflammation
PG  - e992
VI  - 8
IP  - 3
4099  - http://nn.neurology.org/content/8/3/e992.short
4100  - http://nn.neurology.org/content/8/3/e992.full
SO  - Neurol Neuroimmunol Neuroinflamm2021 May 01; 8
AB  - Objective To establish the incidence of demyelination in patients who have received anti–tumor necrosis factor alpha (anti-TNFα) therapy, through analysis of adverse events reported in a prospective cohort of patients receiving biological therapies.Methods A cohort study was performed on prospectively acquired data via the British Society for Rheumatology Biologics Register in Rheumatoid Arthritis. All potential demyelinating events during follow-up were extracted and classified as definite, probable, or possible blinded to treatment data. The point of starting an anti-TNF therapy in individuals with no prior reported demyelination was the time of exposure. Crude rates of demyelination and standardized incident rates (SIRs) compared with the general UK population were calculated.Results Thirty-five individuals with demyelinating events were identified from a total pool of 13,489. The median age at study entry was 44 years, and the median disease duration was 8 years; 71% were female. Events occurred a median of 3 (interquartile range 1–5) years from the start of the first anti-TNF therapy. Twenty-six events occurred in individuals still taking anti-TNFα therapy; of the other 9, 6 were within 90 days of drug withdrawal. The raw incidence of demyelination was 19.7/100,000 patient-years (95% CI 13.7–27.3). The SIR in the whole population was 1.38 (95% CI 0.96–1.92) and 0.83 (0.51–1.26) limited to definite/probable cases.Conclusions Demyelination following anti-TNF therapy is uncommon. Patients receiving anti-TNFα therapy show a marginally increased SIR; this is lost in sensitivity analyses. Patients concerned about anti–TNFα-associated demyelination can be relatively reassured by these data.csDMARD=conventional synthetic disease-modifying antirheumatic drug; IQR=interquartile range; MS=multiple sclerosis; pyears=person-years; RA=rheumatoid arthritis; SIR=standardized incident rate; TNFα=tumor necrosis factor alpha