QTc interval prolongation in patients with systemic lupus erythematosus treated with hydroxychloroquine

The primary objective is to reveal the effect of hydroxychloroquine (HCQ) treatment on corrected QT (QTc) interval in patients with systemic lupus erythematosus (SLE). The secondary objective is to investigate factors that affect QTc prolongation. SLE patients who had electrocardiograms between 2015 and 2020 were recruited and assigned to two groups based on whether they were treated with HCQ (HCQ group) or not (control group). Change of QTc before and after HCQ administration in the HCQ group was measured and compared with the control group. Patients treated with HCQ were further divided into two groups based on presence or absence of QTc prolongation and the characteristics were compared. In total, 126 patients were recruited, of whom 42 were treated with HCQ. In the HCQ group, the mean QTc significantly increased (p