Abstract: PO0860
Interpreting Home Blood Pressure Measurements in Haemodialysis: A Post Hoc Analysis of a Randomized Cross-Over Study
Session Information
- Fluid, Electrolytes, and Clinical Events with Dialysis: Getting to the "Heart" of the Matter
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Dialysis
- 701 Dialysis: Hemodialysis and Frequent Dialysis
Authors
- Sandys, Vicki K., Royal College of Surgeons in Ireland, Dublin, Ireland
- Bhat, Lavleen, Royal College of Surgeons in Ireland, Dublin, Ireland
- O'Hare, Emer Catherine, Royal College of Surgeons in Ireland, Dublin, Ireland
- O'Seaghdha, Conall M., Royal College of Surgeons in Ireland, Dublin, Ireland
- Sexton, Donal J., The University of Dublin Trinity College, Dublin, Ireland
Background
Home BP correlates better with ambulatory BP, target organ damage and mortality in dialysis patients. We aimed to determine the agreement of in-centre BP with home BP.
Methods
A post-hoc analysis of a pilot-scale, randomised two-period cross over study comparing self-monitoring of BP over 4 weeks with usual care in 41 haemodialysis patients. www.clinicaltrials.gov. NCT0340349. Dialysis clinic BP and home BP (using A&D model UA-651BLE device) were averaged over 2 weeks. Agreement was determined using kappa statistics and Bland Altman plots. BP variability was analysed using average real variability (ARV). Mixed effects models for repeated measures with a moving average window of 2 weeks were used to examine associations with BP and ARV.
Results
33 out of 41 participants had sufficient home BP measurements for inclusion (mean age 52 +/- 13 years, 65% male). Post-dialysis SBP had moderate agreement with home SBP measurements (K = 0.6) compared with pre-dialysis SBP measurements (K = 0.4). The mean bias between home SBP and post SBP measurements was -4.15 mmHg (95% CI 23.5 to -31.8 mmHg) (Figure 1). Home SBP ARV (16 +/- 6) was as high as pre SBP ARV (14 +/-5) and post SBP ARV (13 +/-5). In univariate analysis only calcium channel blockers were consistently associated with pre-dialysis (P= 0.02), post-dialysis and home SBP (both P<0.001).
Conclusion
Post-dialysis SBP demonstrates moderate agreement with home BP when two week BP averages are used. Home BP measurements are as variable as clinic BP measurements and isolated measurements may lack interpretability. Averaging the home BP over two weeks may improve the utility of home BP monitoring.
Figure 1: An illustrative BP profile for one study participant a) All home BP raw data compared to in-centre data b) Averaged home BP data on non-dialysis days c) Bland Altman plot of all patients comparing home and post-dialysis BP using 2 week averaged values.
Funding
- Commercial Support – patientMpower