Methods

A case–control study was conducted through interviews based on a structured questionnaire to investigate the frequency of COVID-19 incidence in 254 eligible patients with RA or SpA about whom 45% were under treatment with one type of TNF-α blockers including infliximab, adalimumab, and etanercept at least for 3 months during the COVID-19 pandemic. Interviews were carried out twice, at the beginning and the end of the study (June–December 2020). Patients with COVID-19 during the study or before that were considered as cases. The control group was patients without COVID-19 experience. Data were analyzed using descriptive statistics, and logistic regression was used to determine the relationships between COVID-19 incidence and independent variables.

Results

A small percentage of patients treated with TNF-α blockers (5.22%, 6/115) experienced COVID-19, while a large percentage of patients with COVID-19 did not receive TNF-α blockers (27.34%, 38/139). According to odds ratio, adalimumab, infliximab, and etanercept decreased significantly the risk of developing COVID-19 up to 96.8, 95, and 80.3%(p< 0.05), respectively. Therefore, TNF-α blockers could probably decrease the chances of the COVID-19 incidence in patients with RA or SpA.

Conclusions

A direct and positive correlation between the use of TNF-α blockers and a reduction in the incidence of COVID-19 could suggest the prophylactic role of these drugs in preventing COVID-19 in patients with RA and SpA.