Nearly 33% of patients on hemodialysis have higher blood pressure at home vs at centers
In this study, nearly one-third of patients receiving in-center hemodialysis had higher blood pressure at home than their recorded in-center, pre-dialysis BP and higher left ventricle mass index, suggesting a lack of treatment.
“Why for some patients BP is higher at home than in the office, or in this case, the dialysis unit, is not clear,” Dana C. Miskulin, MD, MA, associate professor of nephrology at Tufts University School of Medicine, and colleagues wrote. They added, “That BP is higher at home the next day than pre-dialysis is particularly striking as the pre-dialysis BP is measured at the highest degree of fluid overload in the dialytic cycle.”
Miskulin and colleagues examined whether BP measures at home are higher than those measured at dialysis centers. In this prospective cohort, researchers analyzed 97 patients on hemodialysis with hypertension who were enrolled in the Blood Pressure and Dialysis Study. Patients’ BP at home and prior to dialysis was recorded at least six times in 1 year. Left ventricular mass index (LVMI) was measured using cardiac magnetic resonance imaging. Miskulin and colleagues applied hierarchical clustering analysis by categorizing patients into three clusters based on their average and variable differences in systolic pre-dialysis and home BP.
On average, researchers took 24 BP measurements at home and at dialysis centers for each patient. The mean age of the patients was 56.7 years; 48.5% were Black, 54% had ESKD due to diabetes, 4.1% had a history of myocardial infarction, 8.3% had peripheral vascular disease and 12.4% had congestive heart failure. Patients were usually on dialysis for about 3 years prior to the study. The first cluster included 31 patients, the second had 36 patients and the third cluster had 30 patients.
The three clusters exhibited average differences between home and pre-dialysis systolic BP of 19.1 mmHg, 3.7 mmHg and -9.7 mmHg, with an increase in only the third cluster. LVMI and daytime BP monitoring were also higher in the third cluster. Intradialytic hypotension occurred less often in the third cluster than the first and second clusters. Researchers recorded slightly higher BP during dialysis and significantly higher BP after dialysis in the third cluster compared with the other clusters.
The small population size studied limited the results. Also, the patients included did not represent the general hemodialysis population, according to researchers.
“The lack of a decline in BP with dialysis may be a signal identifying a patient who will exhibit a ‘home higher’ BP pattern,” Miskulin and colleagues wrote. “The higher LVMI among patients in cluster 3, despite similar pre-dialysis BPs, indicates that home and post-dialysis BPs may better reflect the average BP load than the pre-dialysis BP. The higher LVMI in this group suggests that their high blood pressure at home is under recognized and undertreated.”