Abstract
Background: In chronic kidney disease(CKD), renal dysfunction is associated with a loss of nocturnal blood pressure(BP) reduction. However, it remains unclear about the circadian rhythm of BP in CKD with hypoalbuminemia resulting from urinary protein excretion. We evaluated the relationship between the circadian BP rhythm and serum albumin level(S-Alb).
Methods: Non-diabetic CKD patients without progressive renal dysfunction(serum creatinine level<1.5mg/dl) were divided into two groups, based on S-Alb: nephrotic syndrome(NS) group(less than 3.0g/dl; n=30) and Hypoalbuminemia group(3.0 to 4.0g/dl; n=32). Age and sex-matched normal subjects with normal albumin level(more than 4.0g/dl; n=32) were enrolled as Control group. Ambulatory 24-hour BP monitoring was conducted in all subjects.
Results: There were no significant differences in 24-hour BP among three groups. However, sleeping/waking mean BP ratios were significantly increased gradually in the Control, Hypoalbuminemia and NS groups, in that order(0.85±0.07, 0.91±0.08, 0.96±0.08, respectively; p<0.05 for respective two groups). A significant reverse correlation was observed between S-Alb and sleeping/waking ratio of mean BP(r=−0.58; p<0.001).
Conclusion: In non-diabetic CKD patients, loss of nocturnal BP reduction occurred even in the early stage, correlating with S-Alb.
