Correlation between Intradialytic Blood Pressure Variability and Cognitive Impairment in Patients on Maintenance Hemodialysis

Background: Cognitive impairment (CI) is a risk factor for death and poor prognosis in maintenance hemodialysis (MHD) patients. MHD patients are more likely to have fluctuating BP during dialysis, which may have a greater impact on CI. Our present study aimed to illustrate the correlation between intradialysis BPV and CI in MHD patients. Methods: Overall cognitive function was assessed by the Beijing version of the Montreal Cognitive Assessment (MoCA-B) scale. The patient's SBP was converted to the following 4 candidate BPV indices: standard deviation (SD), coefficient of variation (CV), average real variability (ARV), RANGE. P < 0.05 was considered statistically significant. Results: 170 patients were enrolled, with a total of 6,662 dialysis recordings and 26,580 SBP measurement recordings. The mean age of the patients was 57.99 years. The proportion of males was 58.24%, and CI prevalence was 78.24%. SBP ARV is an independent risk factor for CI (Table 1). We observed a non-linear relationship between SBP ARV and CI (Figure 1). We compared two fitting models to explore the curved associations, the p-value of the log-likelihood ratio test is 0.008. The inflection point of SBP ARV was 7.52. When SBP ARV ≥ 7.52, the risk of CI increased as the SBP ARV increased (OR: 4.10, 95 % CI1.61-10.46, P = 0.003). When SBP ARV < 7.52, there was no significant correlation between SBP ARV and CI (OR = 0.43, 95 % CI 0.15-1.26, p = 0.125). Conclusion: Intradialytic BPV was associated with CI in MHD patients. Intradialytic SBP ARV may be a better candidate for predicting CI in MHD patients, with nonlinear dose-response relationship. Funding: Government Support – Non-U.S.Table1. The results of mutivariate analysis between SBP ARV and CIFigure 1.Curve fitting between SBP ARV and CI.