Association of frequent intradialytic hypotension with the clinical outcomes of patients on hemodialysis: a prospective cohort study

Abstract

Intradialytic hypotension (IDH) is a common complication of hemodialysis (HD), but there is no consensus on its definition. In 2015, Flythe proposed a definition of IDH (Definition 1 in this study): nadir systolic blood pressure (SBP) <90 mmHg during hemodialysis for patients with pre-dialysis SBP <159 mmHg, and nadir SBP <100 mmHg during hemodialysis for patients with pre-dialysis SBP ≥160 mmHg. This prospective observational cohort study investigated the association of frequent IDH based on Definition 1 with clinical outcomes and compared Definition 1 with a commonly used definition (nadir SBP <90 mmHg during hemodialysis, Definition 2). The incidence of IDH was observed over a 3-month exposure assessment period. Patients with IDH events ≥30% were classified as ‘frequent IDH’; the others were ‘infrequent IDH’. All-cause mortality, cardiovascular mortality, and all-cause hospitalization events were followed up for 36 months. This study enrolled 163 HD patients. The incidence of IDH was 11.1% according to Definition 1 and 10.5% according to Definition 2. The Kaplan-Meier curves showed that frequent IDH patients had higher risks of all-cause mortality (p = 0.009, Definition 1; p = 0.002, Definition 2) and cardiovascular mortality (p = 0.021, Definition 1). Multivariable Cox regression analysis indicated that frequent IDH was independently associated with a higher risk of all-cause mortality (Model 1: HR = 2.553, 95%CI 1.334–4.886, p = 0.005; Model 2: HR = 2.406, 95%CI 1.253–4.621, p = 0.008). In conclusion, HD patients classified as frequent IDH are at a greater risk of all-cause mortality. This highlights the significance of acknowledging and proactively managing frequent IDH within the HD patients.

Keywords:

• Intradialytic hypotension
• hemodialysis
• all-cause mortality
• cardiovascular mortality
• all-cause hospitalization

Acknowledgments

The authors express their gratitude to the participants for their cooperation in the study.

Authors’ contributions

YW, JL, and LY conceived and designed the study. YW, TW, XZ, and JX provided data interpretation. LY and JL conducted the data analysis. YW and JL drafted and revised the manuscript. YW and JL were responsible for data collection. YW performed patient recruitment. YW and JL contributed equally to this work. All authors have reviewed and approved the manuscript for submission.

Disclosure statement

The authors declare no conflicts of interest.

Ethics approval and consent to participate

The study adhered to the Declaration of Helsinki guidelines. The Institutional Ethics Review Board of Huashan Hospital, Fudan University, approved the study protocol (IRB No. KY2016-394). Written informed consent was obtained from all participants.

Data availability statement

The datasets used and/or analyzed during the current study are available from the corresponding author upon reasonable request.

Additional information

Funding

This study was funded by grants from the Scientific Research Projects of Shanghai Municipal Health Commission (#201940271).