Pro-inflammatory cytokines as potential predictors for intradialytic hypotension.

Background: Intradialytic hypotension (IDH) is a common complication in maintaining hemodialysis (MHD) patients. Immune activation might be part of the mechanisms. However, the association between pro-inflammatory cytokines and blood pressure (BP) has not been deeply explored. So we aim to evaluate the potential role of pro-inflammatory cytokines in IDH.
Methods: MHD patients starting hemodialysis before January 2016 were enrolled in our retrospective study. Patients' characteristics, laboratory results, and intradialytic BP were collected. IDH was defined as nadir systolic BP ≤ 90 mmHg during hemodialysis. The definition of IDH group was that those who suffered from more than one hypotensive event during one month after the enrollment (10% of dialysis treatments). Spearman correlation analysis and logistic regression were employed to explore the relationship between pro-inflammatory cytokines and IDH.
Results: Among 390 patients, 72 were identified with IDH (18.5%). High levels of serum tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were observed in the IDH group ( p  < 0.001). Both TNF-α and IL-1β positively correlated with predialysis BP ( p  < 0.01). Receiver operating characteristic curve (ROC) analysis was used to evaluate the diagnostic accuracy of serum IL-1β and TNF-α for IDH. The area under the curve of IL-1β was 0.772 (95% CI: 0.708-0.836, p  < 0.01), and that of TNF-α was 0.701 (95% CI: 0.620-0.781, p  < 0.01). After adjusting for patients' characteristics, biochemical parameters, comorbid conditions, predialysis BP, and medications, elevated TNF-α and IL-1β were still risk factors for IDH.
Conclusion: Pro-inflammatory cytokines (TNF-α and IL-1β) could be potential predictors for IDH.