Evaluation of QTc and Tp-e changes in rheumatoid arthritis and ankylosing spondylitis patients treated with biological drugs

Tumor necrosis factor-α (TNF-α) antagonists bring about significant improvement in chronic inflammatory diseases such as rheumatoid arthritis (RA) and spondyloarthritis (SpA), but they may have negative myocardial effects. This study aimed to evaluate the changes in QT corrected (QTc) and T-peak to T-end (TpTe) in RA and AS patients treated with biological drugs.

This cross-sectional study included all eligible patients referred to Imam Khomeini Hospital, Urmia, Iran from March 2021 to February 2022 and were randomly divided into two groups (anti-TNF group treated with methotrexate, rituximab, etanercept, adalimumab, infliximab and control group treated with methotrexate). Electrocardiogram (ECG) was performed on all participants at baseline and 6 months after initiation of treatment, and the QT, QTd, and TpTe were calculated with standard procedures.

Of 128 patients with RA or AS, 64 patients were included in the anti-TNF group and control group, separately. There was predominance of male gender: 69 (53.9%) vs. 59 (46.1%) among all patients with mean age of 47.77 years. After 6 months (T6), the anti-TNF group already displayed a longer mean QT, QTc, and TpTe interval than control group (418.7±15.6. ms vs. 414.0±17.5 ms; p = 0.03; 461.7±25. 0 vs. 448.3±11.2, p=0.2; 71.4±6.7 vs. 70.4±7.4, p=0.6, respectively). Post treatment increases in the QT were detected exclusively in the subgroup of patients being treated with Infliximab, Etanercept, Adalimumab, Rituximab for RA, which all were significant (P= 0.002, 0.001, 0.001, 0.001, respectively). In contrast, post treatment changes in the QTc and TpTe indices were not outstanding and statistically significant.

This study demonstrated that anti-TNF drugs induce a substantial increase in QT and QTc levels, which can cause considerable risks to patients due to their asymptomatic presentation. Unlike antiTNF drugs, methotrexate does not cause significant changes in these parameters.