Disparate Estimates of Hypertension Control From Ambulatory and Clinic Blood Pressure Measurements in Hypertensive Kidney Disease.
Hypertension. 2008 Dec 1. Pogue V, Rahman M, Lipkowitz M, Toto R, Miller E, Faulkner M, Rostand S, Hiremath L, Sika M, Kendrick C, Hu B, Greene T, Appel L, Phillips RA; for the African American Study of Kidney Disease Hypertension Collaborative Research Group. Division of Nephrology, Department of Medicine, Columbia University Medical Center at Harlem Hospital, New York, NY; Division of Hypertension, Case Western Reserve University, Cleveland, Ohio; Division of Nephrology, Mount Sinai Medical School, New York, NY; Division of Nephrology, University of Texas Southwestern Medical Center, Dallas; Welch Center for Prevention, Epidemiology, and Clinical Research, Johns Hopkins University, Baltimore, Md; Department of Medicine, Meharry Medical College, Nashville, Tenn; Division of Nephrology, University of Alabama at Birmingham; Division of Nephrology Ohio State University, Columbus; Division of Nephrology, Vanderbilt University, Nashville, Tenn; Department of Biostatistics and Epidemiology, Cleveland Clinic Foundation, Ohio; Division of Clinical Epidemiology, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City; and the Heart and Vascular Center of Excellence, University of Massachusetts Medical School, Worcester.
Ambulatory blood pressure (ABP) monitoring provides unique information about day-night patterns of blood pressure (BP). The objectives of this article were to describe ABP patterns in African Americans with hypertensive kidney disease, to examine the joint distribution of clinic BP and ABP, and to determine associations of hypertensive target organ damage with clinic BP and ABP. This study is a cross-sectional analysis of baseline data from the African American Study of Kidney Disease Cohort Study. Masked hypertension was defined by elevated daytime (>/=135/85 mm Hg) or elevated nighttime (>/=120/70 mm Hg) ABP in those with controlled clinic BP (<140/90 mm Hg); nondipping was defined by a </=10% decrease in mean nighttime systolic BP; reverse dipping was defined by a higher nighttime than daytime systolic BP. Of the 617 participants (mean age: 60.2 years; 62% male; mean estimated glomerular filtration rate: 43.8 mL/min per 1.73 m(2)) with both clinic BP and ABP, 498 participants (80%) had a nondipping or reverse dipping profile. Of the 377 participants with controlled clinic BP (61%), 70% had masked hypertension. Compared with those with controlled clinic BP or white-coat hypertension, target organ damage (proteinuria and left ventricular hypertrophy) was more common in those with elevated nighttime BP, masked hypertension, or sustained hypertension
In conclusion, clinic BP provides an incomplete and potentially misleading assessment of the severity of hypertension in African Americans with hypertensive kidney disease, in large part because of increased nighttime BP. Whether lowering nighttime BP improves clinical outcomes is unknown but should be tested given the substantial burden of BP-related morbidity in this population.