The difference between nocturnal dipping status and morning blood pressure surge for target organ damage in patients with chronic kidney disease

Abstract

The authors aimed to investigate the epidemiology of morning blood pressure (BP) surge (MBPS) in chronic kidney disease (CKD) patients, and the interaction effect between MBPS and dipping status for target organ damage (TOD). A total of 823 non-dialysis CKD patients were enrolled in this cross-sectional study. Subjects were grouped according to their systolic BP morning surge and dipping status, assessed by 24-hour ambulatory BP monitoring. Patients with elevated MBPS had the highest quartile of MBPS (≥26.89 mm Hg). Non-dipping pattern was defined as a decline in the nocturnal systolic BP of <10%. The factorial-designed analysis of variance indicated that there was no statistically significant interaction effect for TOD between MBPS and dipping status (P > .05). There was a statistically significant association between MBPS and the non-dipping pattern (OR 0.17, 95% CI 0.12-0.25; OR 0.92, 95% CI 0.91-0.93). Multiple linear regression analyses showed that excessive MBPS is an independent risk factor for poor renal function, independent of a non-dipping pattern, and BP level, whereas the non-dipping pattern was an important risk factor for left ventricular hypertrophy. Special attention should be paid to synchronous control of MBPS and nocturnal BP in CKD patients in clinical practice.

Keywords: ambulatory blood pressure monitoring; chronic kidney disease; morning blood pressure surge; non-dipping pattern; target organ damage.

FIGURE 1

Comparison of the prevalence of elevated morning blood pressure surge in different CKD stages. CKD, chronic kidney disease

FIGURE 2

Comparison of target organ damage in four groups (by Bonferroni method [six comparisons]). ^*Comparison with the non‐MBPS and dipping pattern groups (P < .05). ^#Comparison with the non‐MBPS and non‐dipping pattern groups (P < .05). LVH, left ventricular hypertrophy; MBPS, morning blood pressure surge