Association between elevated serum parathyroid hormone and QTc interval prolongation in chronic kidney disease patients.

PURPOSE: Heart rate-corrected (QTc) interval prolongation is frequently linked to fatal arrhythmias and sudden cardiac death in chronic kidney disease (CKD) patients. In this cross-sectional study, we assessed the prevalence of prolonged QTc intervals and identified clinical factors associated with them across different stages of kidney failure.

METHODS

723 patients with CKD stages 2-5 who had electrocardiogram records available were analyzed retrospectively. QTc intervals were calculated by correcting the QT intervals for all patients included in the study. QTc interval prolongation defined as a QTc interval ˃ 440 ms was assessed for its prevalence and its association with various clinical factors.

RESULTS

A total of 723 patients with CKD stages 2-5 were finally included in this study, among which 420 (58.1%) were male. The average age of the participants was 48.2 ± 14.6 years old. In patients with CKD stages 2-4, the prevalence of QTc interval prolongation was 26%, 24.1%, and 37.8%, respectively. Among patients with CKD stage 5, those not on dialysis had a prevalence of 63%, while those undergoing dialysis had a prevalence of 74.3%. Multivariate logistic regression analysis revealed that elevated levels of parathyroid hormone (PTH) were significantly associated with an increased risk of QTc intervals prolongation in CKD patients (aOR = 1.384, 95% CI 1.173-1.632; P < 0.001). This suggests that higher PTH levels may contribute to QTc interval prolongation in this population. The patients were then grouped by CKD stages. Elevated PTH levels were independently associated with an increased risk of QTc interval prolongation specifically in CKD stages 4 and 5 patients who were not on dialysis. After adjusting for potential confounders, this association remained significant (CKD stage 4: aOR = 2.571, 95% CI 1.030-6.416; P < 0.001; CKD stage 5, non-dialysis: aOR = 1.333, 95% CI 1.063-1.671; P < 0.001).

CONCLUSION

In patients with CKD, the prevalence of QTc prolongation increases with advancing CKD stages. Specially, among patients with CKD stage 4 and stage 5 who were not on dialysis, elevated PTH levels were independently associated with an increased risk of QTc interval prolongation.