Quantification of longitudinal patient-reported burden of adverse drug reactions attributed to the use of TNF-α inhibitors in inflammatory rheumatic diseases: an observational prospective cohort study.

Background: There is a lack of knowledge on patient perspectives on adverse drug reactions (ADRs) attributed to the use of biologics. The aim of this study is to quantify the burden over time of ADRs attributed to TNF-α inhibitors in patients with inflammatory rheumatic diseases (IRDs) and investigate whether the burden over time differs between different types of ADRs.

Research design and methods: Data were used from the Dutch Biologic Monitor (DBM), an observational prospective cohort study for patient-reported ADRs attributed to biologics. Patients with an IRD using a TNF-α inhibitor reporting an ADR, lasting for three consecutive questionnaires, were included. Questionnaires were sent every 2 months and the burden was scored on a 5-point Likert-type scale. Burden scores were analyzed using linear mixed models.

Results: Data from 166 unique patients reporting 274 ADRs were included. The burden score decreased every month by 0.29 points (95% CI -0.34 - -0.24) on average on a 5-point Likert-type scale. The burden score for infections and infestations decreased significantly faster than the burden score for injection site reactions.

Conclusions: Patient-reported burden of ADRs attributed to the use of a TNF-α inhibitor in patients with IRDs decreased significantly over time, especially for infections and infestations.