Association between blood pressure and target organ damage in patients with chronic kidney disease and hypertension: results of the APrODiTe study

Blood pressure control is the most established practice for preventing the progression of chronic kidney disease. Evidence addressing blood pressure control status or nocturnal blood pressure dipping in Korean hypertensive patients with chronic kidney disease is scarce. We recruited 1317 hypertensive patients (chronic kidney disease stages 2-4, median age 58) from 21 centers in Korea. These patients underwent office and ambulatory blood pressure monitoring. High office and ambulatory blood pressure were defined as > 140/90 mm Hg and > 135/85 mm Hg (daytime)/ > 120/70 mm Hg (nighttime), respectively. The blood pressure control status was as follows: true controlled (19%), white-coat (4.3%), masked (33.9%) and sustained uncontrolled (42.3%) hypertension. The dipping status was as follows: extreme-dipping (14.9%), dipping (33.3%), non-dipping (34.5%) and reverse-dipping (17.3%). Masked and sustained hypertension as well as non-dipping/reverse-dipping was more apparent in proportion to renal dysfunction and the extent of proteinuria. Ageing (>= 58 years), male gender, obesity, diabetic nephropathy and proteinuria (> 300 mg g(-1) Cr or dipstick proteinuria >= 1 +) were independently associated with sustained uncontrolled hypertension. Diabetic nephropathy, old age, a history of stable angina/heart failure, advanced renal dysfunction and higher proteinuria levels were also significantly associated with non-dipping and reverse-dipping. Half of Korean chronic kidney disease patients had uncontrolled blood pressure and a non-dipping nocturnal blood pressure pattern. Future studies are warranted to assess the predictive values of ambulatory blood pressure for cardiorenal events in Korean chronic kidney disease patients.