PHILADELPHIA—Elevated systolic blood pressure (SBP) contributes substantially to rapid declines in renal function in older adults, investigators reported at Kidney Week 2011.
Dena E. Rifkin, MD, of the University of California in San Diego, and colleagues made the discovery when they studied 4,365 older adults (average age 72.2 years) participating in the Cardiovascular Health Study. The group’s mean SBP, diastolic blood pressure (DBP), and pulse pressure (PP) were 135, 71, and 65 mm Hg, respectively.
The researchers used cystatin C measurements to estimate glomerular filtration rate on three occasions over seven years of follow-up. They defined rapid decline in renal function as a lost of 3 mL/min/year or more.
Their analyses showed that each 10 mm Hg increment in SBP was associated with an added decline of 0.13 mL/min/year; each 10 mm Hg increment in PP was associated with an added decline of 0.15 mL/min/year; and each 10 mm Hg increment in DBP was associated with an added decline of 0.10 mL/min/year. In an adjusted model, SBP had the strongest association with rapid decline, with each 10 mm Hg increment in conferring a 14% increased risk of rapid decline. In models combining BP components, only SBP was independently associated with rapid decline, the researchers stated.