Uncertainties in BP management in dialysis patients

Interdialytic Blood Pressure and Risk of Cardiovascular Events and Death in Hemodialysis Patients

INTRODUCTION

Normal (120-140 mm Hg) systolic peridialysis blood pressure (BP) is associated with higher mortality in hemodialysis (HD) patients.

AIM

We explored the relationship between hypertension and BP on outcomes using data collected at the interdialytic period.

METHODS

This was a single-center observational cohort study with 2672 HD patients. BP was determined at inception, in mid-week, between 2 consecutive dialysis sessions. Hypertension was defined as systolic BP ≥ 140 mm Hg and/or diastolic BP ≥ 90 mm Hg. Endpoints were major CV events and all-cause mortality.

RESULTS

During a median follow-up of 31 months, 761 patients (28%) experienced CV events and 1181 (44%) died. Hypertensive patients had lower survival free of CV than normotensive patients (P = 0.031). No difference occurred in the incidence of death between groups. Compared with the reference category of SBP ≥ 171 mmHg, the incidence of cardiovascular events was reduced in patients with SBP 101-110 (HR 0.647, 95% CI 0.455 to 0.920), 111-120 (HR 0.663, 95%CI 0.492 to 0.894), 121-130 (HR 0.747, 95%CI 0.569 to 0.981), and 131-140 (HR 0.757, 95%CI 0.596 to 0.962). On multivariate analysis, systolic and diastolic BP were not independent predictors of CV events or death. Normal interdialytic BP was not associated with mortality or CV events, and hypertension predicted an increased probability of CV complications.

CONCLUSIONS

Interdialytic BP may be preferred to guide treatment decisions, and HD patients should be treated according to guidelines for the general population until specific BP targets for this population are identified.

Management of hypertension in patients with diabetic kidney disease: Summary of the Joint Association of British Clinical Diabetologists and UK Kidney Association (ABCD-UKKA) Guideline 2021

Diabetic kidney disease (DKD) accounts for >40% cases of chronic kidney disease (CKD) globally. Hypertension is a major risk factor for progression of DKD and the high incidence of cardiovascular disease and mortality in these people. Meticulous management of hypertension is therefore crucial to slow down the progression of DKD and reduce cardiovascular risk. Randomized controlled trial evidence differs in type 1 and type 2 diabetes and in different stages of DKD in terms of target blood pressure (BP). Renin-angiotensin blocking agents reduce progression of DKD and cardiovascular events in both type 1 and type 2 diabetes, albeit differently according to the stage of CKD. There is emerging evidence for the benefit of sodium glucose cotransporter 2, nonsteroidal selective mineralocorticoid antagonists, and endothelin-A receptor antagonists in slowing progression and reducing cardiovascular events in DKD. This UK guideline, developed jointly by diabetologists and nephrologists, has reviewed all available current evidence regarding the management of hypertension in DKD to produce a set of comprehensive individualized recommendations for BP control and the use of antihypertensive agents according to age, type of diabetes, and stage of CKD (https://ukkidney.org/sites/renal.org/files/Management-of-hypertension-and-RAAS-blockade-in-adults-with-DKD.pdf). A succinct summary of the guideline, including an infographic, is presented here.

Association of blood pressure after peritoneal dialysis initiation with the decline rate of residual kidney function in newly-initiated peritoneal dialysis patients

Background

Lower blood pressure (BP) levels are linked to a slower decline of kidney function in patients with chronic kidney disease (CKD) without kidney replacement therapy. However, there are limited data on this relation in peritoneal dialysis (PD) patients. Here we evaluated the association of BP levels with the decline of residual kidney function (RKF) in a retrospective cohort study.

Methods

We enrolled 228 patients whose PD was initiated between 1998 and 2014. RKF was measured as the average of creatinine and urea clearance in 24-hr urine collections. We calculated the annual decline rate of RKF by determining the regression line for individual patients. RKF is thought to decline exponentially, and thus we also calculated the annual decline rate of logarithmic scale of RKF (log RKF). We categorized the patients’ BP levels at 3 months after PD initiation (BP_3M) into four groups (Optimal, Normal & High normal, Grade 1 hypertension, Grade 2 & 3 hypertension) according to the 2018 European Society of Cardiology and European Society of Hypertension Guidelines for the management of arterial hypertension.

Results

The unadjusted, age- and sex-adjusted, and multivariable-adjusted decline rate of RKF and log RKF decreased significantly with higher BP_3M levels (P for trend <0.01). Compared to those of the Optimal group, the multivariable-adjusted odds ratios (95% confidence interval) for the faster side of the median decline rate of RKF and log RKF were 4.04 (1.24–13.2) and 5.50 (1.58–19.2) in the Grade 2 and 3 hypertension group, respectively (p<0.05).

Conclusions

Higher BP levels after PD initiation are associated with a faster decline in RKF among PD patients.