Lower nocturnal SBP tied to less cardiovascular, renal damage in normotensive CKD patients

Nocturnal systolic blood pressure (SBP) is independently associated with target organ damage (TOD) in normotensive patients with chronic kidney disease (CKD), suggests a recent study.

A team of investigators determined whether nocturnal BP correlated with cardiovascular and renal damage independent of the 24-h BP in 1,166 hospitalized CKD patients not requiring dialysis. Of these, 421 had normotension and 745 were hypertensive.

The investigators assessed TOD through the left ventricular mass index (LVMI), estimated glomerular filtration rate (eGFR), and presence of proteinuria. They evaluated the associations between nocturnal BP and TOD using univariate and multivariable regression analyses.

Nocturnal SBP independently correlated with LVMI, eGFR, and proteinuria among normotensive patients (p<0.05) in multivariable-adjusted models, including the 24-h BP; on the other hand, nocturnal diastolic (D)BP was not associated with proteinuria.

Nocturnal SBP also correlated with LVMI and proteinuria, but not eGFR, in hypertensive patients; however, the investigators failed to find a link between nocturnal DBP and TOD in this cohort.

Upon further categorization into tertiles of nocturnal SBP in patients with normotension (tertile 1: <104 mm Hg; tertile 2: 104–114 mm Hg; tertile 3: ≥114 mm Hg), multivariate analysis revealed an independent association between tertile 3 and TOD.

“Targeting a nocturnal ambulatory SBP to <114 mm Hg or even <104 mm Hg may help prevent TOD in patients with CKD,” the investigators said.