Blood Pressure Variability May Be Associated With CV Events, Mortality in Patients With Nondialysis Chronic Kidney Disease

Blood pressure variability (BPV) may be associated with cardiovascular events and death but not end-stage kidney disease (ESKD) in patients with nondialysis chronic kidney disease (CKD) stages 1 to 5, according to a study published in Hypertension.

In this observational cohort study, US veterans aged ≥18 years with nondialysis CKD stages 1 to 5 and hypertension were enrolled between January 2010 and December 2016. Of 332,401 veterans who met the criteria for inclusion, 68,739 were on nondiuretic antihypertensive monotherapy and had a diuretic as second antihypertensive medication, and 263,662 participants had a nondiuretic as a second agent.

Patients were propensity-matched 1:1, resulting in 31,394 participants in each group (mean age, 72.2 years; 3.8% women). Participants were followed for up to 5 years.

The study’s primary outcome was a composite of cardiovascular events (fatal or nonfatal myocardial infarction, fatal or nonfatal ischemic stroke, or hospitalization for heart failure). Secondary outcomes included all-cause death, each component of the primary composite outcome, ESKD, and cardiovascular death (death within 31 days of a myocardial infarction, ischemic stroke, or hospitalization for heart failure). BPV was the coefficient of systolic blood pressure variation for 6 months after prescription of the second agent.

BPV was found to be associated with the primary outcome (hazard ratios compared with the first BPV quintile: second quintile, 1.79; 95% CI, 1.53-2.11; third quintile, 2.32; 95% CI, 1.99-2.71; fourth quintile, 2.60; 95% CI, 2.24-3.02; fifth quintile, 3.12; 95% CI, 2.68-3.62). Diuretics as second agents diminished associations between the fourth and fifth BPV quintiles with the primary outcome (P_interaction =.03 and .04, respectively). BPV was associated with all secondary outcomes except ESKD, and no interactions with treatment with diuretics were detected.

“We demonstrated that BPV was strongly associated with composite cardiovascular events, all-cause death, cardiovascular death, myocardial infarction, hospitalization for heart failure, and ischemic stroke in patients with prevalent nondialysis CKD stages 1-5,” noted the study authors. “There was no association between BPV and ESKD. The association of BPV with cardiovascular events was seen across all subgroups but was attenuated in individuals with diabetes. Diuretic prescription modified the association of BPV with cardiovascular events at the highest BPV quintiles.”

Study limitations include the fact that cardiovascular outcomes were solely determined from Veterans Administration data, and may not have taken into account events occurring outside the VA system.

“It is possible that BPV has a complex underlying pathophysiology mediated by factors other than extracellular volume or that high BPV is a marker of overall poor cardiovascular health,” the researchers commented. “Nonetheless, BPV remains a promising target to improve outcomes in patients with CKD, so further studies should investigate whether other classes of antihypertensive agents impact BPV and its associations with outcomes.”

Disclosures: Some of the authors reported affiliations with pharmaceutical companies. Please see the original reference for a full list of disclosures.

Reference

Gregg LP, Hedayati SS, Yang H, et al. Association of blood pressure variability and diuretics with cardiovascular events in patients with chronic kidney disease stages 1–5 [published online January 11, 2021]. Hypertension. doi: 10.1161/HYPERTENSIONAHA.120.16117