Visit-to-visit ultrafiltration volume variability predicts all-cause mortality in patients receiving hemodialysis

Abstract

Purpose

Little is known about the effect of visit-to-visit ultrafiltration volume (UV) variability on the outcome. In this study, we investigated the association between visit-to-visit UV variability and all-cause mortality in patients receiving hemodialysis (HD).

Methods

We consecutively enrolled patients who received maintenance HD in our center from March 2015 to March 2021. UV variability was defined using standard deviation (UVSD) and coefficient of variation (UVCV) (standard deviation divided by the mean). The relationship between UV variability and all-cause mortality was assessed using univariate and multivariate Cox proportional hazard regression models. Receiver operating characteristic curves were used to evaluate the predictive abilities of UVSD and UVCV for short-term and long-term survival rates.

Results

A total of 283 HD patients were included. The mean age was 57.54 years, and 53% were males. Follow-up was done for a median of 3.38 years (IQR 1.83–4.78). During the follow-up period, 73 patients died. Cox proportional hazards models indicated that UVSD and UVCV (higher versus lower) were positively associated with all-cause mortality (p=.003 and p<.001, respectively), while in multivariable-adjusted models, only higher UVCV remained significantly associated with all-cause mortality in patients receiving HD (HR 2.55 (95% CI 1.397–4.654), p=.002). Moreover, subgroup analyses showed that the predictive performance of UVCV was more accurate among older patients, males and patients with comorbidities.

Conclusions

Visit-to-visit UV variability, especially UVCV, is a helpful indicator for predicting all-cause mortality in patients receiving HD, especially for older patients, males and those with comorbidities.

Keywords:

• Visit-to-visit
• ultrafiltration volume
• variability
• mortality
• hemodialysis

Ethical approval

The study protocol was approved by the ethical committee of Xinqiao Hospital (approval number 2022-yan-465-01), and was in accordance with the principles of the Declaration of Helsinki. The ethical committee exempted informed consent because the medical records was obtained during previous clinical treatment in present study and the exemption would not adversely affect patients’ rights and health.

Author contributions

Q.Z. was responsible for study design, data interpretation, statistical analysis, and manuscript drafting. Q.Z., N.W., L.N., C.L., H.C., WH., M.L., and Y.W. were responsible for data collection. J.Z. and J.X were responsible for the study design, data interpretation, and manuscript revision.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data that support the findings of this study are not publicly available due to their containing information that could compromise the privacy of research participants but are available from the corresponding author.

Additional information

Funding

This work was supported by grants from the National Natural Science Foundation of China [No. 82101967].