Discrepancies in clinic and ambulatory blood pressure in korean chronic kidney disease patients

Blood pressure (BP) control is considered the most important treatment for preventing chronic kidney disease (CKD) progression and associated cardiovascular complications. However, clinic BP is insufficient to diagnose hypertension (HT) and to monitor overall BP control because it does not correlate well with ambulatory blood pressure monitoring (ABPM). We enrolled 387 hypertensive CKD patients (stages G1-G4, 58.4% male with median age 61 years) from 3 hospitals in Korea. HT of clinic BP and ABPM was classified as ≥ 140/90 and ≥ 130/80 mmHg, respectively. Clinic BP control rate was 60.2%. The median 24-hour systolic blood pressures (SBPs) of CKD G3b and CKD G4 were significantly higher than those of CKD G1-2 and CKD G3a. However, the median 24-hour SBPs were not different between CKD G1-2 and CKD G3a or between CKD G3b and CKD G4. Of all patients, 5.7%, 38.0%. 42.3%, and 14.0% were extreme-dippers, dippers, non-dippers, and reverse-dippers, respectively. Non-/reverse-dippers independently correlated with higher Ca × P product, higher intact parathyroid hormone (iPTH), and lower albumin. Normal BP was 33.3%, and sustained, masked, and white-coat HT were 29.7%, 26.9%, and 10.1%, respectively. White-coat HT independently correlated with age ≥ 61 years and masked HT independently correlated with CKD G3b/G4. In conclusion, ABPM revealed a high prevalence of non-/reverse-dippers and sustained/masked HT in Korean CKD patients. Clinicians should try to obtain a CKD patient's ABPM, especially among those who are older or who have advanced CKD as well as those with abnormal Ca × P product, iPTH, and albumin.