Monitoring the effect of TNF-alpha inhibitors on laboratory parameters and adverse effects in different diseases: a retrospective, single-center study.

Background: The introduction of biological treatments has revolutionized the management of moderate-to-severe psoriasis. Multiple clinical trials have established the efficacy of biological agents in the treatment of moderate-to-severe psoriasis. Nevertheless, there are no clear indications for optimal monitoring intervals during treatment.

Objectives: Collect and analyze laboratory evaluation data from patients receiving biological therapy to provide a better understanding of the need for laboratory investigations before and during treatment with biological agents, and to analyze adverse events and other factors.

Design: Retrospective cohort SETTINGS: Tertiary care center in Riyadh, Saudi Arabia.

Patients and methods: Data were collected from the electronic medical records of patients attending the dermatology, rheumatology, and gastroenterology clinics from June 2014 to June 2019. The laboratory parameters of patients who have received one of the TNF-alpha inhibitors (adalimumab, etanercept, or infliximab) were collected starting at baseline and up to at least one year from treatment initiation.

Main outcome measures: The time points at which patients developed significantly abnormal laboratory results during treatment with one of the TNF-alpha inhibitors.

Sample size: 250 patients RESULTS: Most patients were treated with adalimumab (38.4%); a similar proportion (38%) with infliximab, whereas only 23.6% were treated with etanercept. The majority of the significant abnormal laboratory results occurred at baseline, 3-6 and 9-12 months. Most abnormalities were among patients using infliximab, followed by etanercept, and then adalimumab. The median number of laboratory abnormalities for dermatology patients was significantly lower than that for gastroenterology patients (P<.001), and for rheumatology patients (P=.002).

Conclusions: Because dermatology patients showed a lower median number of laboratory abnormalities than patients treated by other specialties in our study, we believe that dermatology patients require less frequent laboratory monitoring. Therefore, we recommend laboratory evaluation at baseline, after 3-6 months, 1 year from the beginning of treatment, and annually thereafter for patients using TNF-alpha inhibitor agents. However, more frequent testing might be warranted according to patient comorbidities, concomitant medications, and physician judgment.

Limitations: Single center and retrospective design.

Conflict of interest: None.