Abstract 066: Association Between Nocturnal Blood Pressure Dipping Magnitude And Chronic Kidney Disease Risk Among Patients With Controlled Office Blood Pressure

Abstract

Although abnormal diurnal blood pressure (BP) patterns are associated with adverse cardiorenal outcomes, their risks are yet unquantified by BP dipping magnitude. We assessed chronic kidney disease risk across nocturnal BP dipping spectrum among patients with controlled hypertension without prior advanced kidney disease. Ambulatory BP measurements were collected from 995 middle-aged patients with controlled office BP (<140/90 mmHg). The magnitude of dipping was defined as the difference between daytime and nighttime systolic BP divided by daytime systolic BP. Accordingly, patients were categorized as extreme-dipper (≥20%) dipper (10-<20%), non-dipper (0-<10%), or reverse-dipper (<0%). We cross-sectionally analyzed continuous and categorical associations of dipping with albuminuria (urine albumin-to-creatinine ratio ≥30 mg/g) and decreased estimated glomerular filtration rate (<60 ml/min/1.73m 2 ), adjusting for office/ambulatory BP, antihypertensive class, body mass index, total cholesterol, fasting glucose, socioeconomic status, and health behavior. The participants (mean age 60.2 years; 52.9% male) consisted of 13.5% (134 of 995) extreme-dippers, 43.1% (429 of 995) dippers, 34.7% (345 of 995) non-dippers, and 8.7% (87 of 995) reverse-dippers. In reference to dippers, odds ratios (95% confidence interval) for albuminuria were 1.73 (1.04-2.60) in reverse-dippers, 1.67 (1.20-2.32) in non-dippers, and 0.62 (0.38-1.04) in extreme-dippers; this reflects significantly lower risk (0.77, 0.55-0.95) per 10% dipping. Likewise, persons presenting reduced and reverse-directional dipping were at higher risk for decreased estimated glomerular filtration rate: reverse-dippers 2.02 (1.06-3.84); non-dippers 1.98 (1.07-3.08); extreme-dippers 0.69 (0.20-1.17), with lower risk (0.74, 0.22-1.02) per every 10%. In short, monitoring nocturnal BP patterns may identify chronic kidney disease risk otherwise overlooked based on office BP.