Abstract 010: Prevention of Chronic Kidney Disease: Impact of Addressing the Blood Pressure Distribution, Not Just the Tail

Abstract

Background: While much of the chronic kidney disease (CKD) literature focuses on the role of blood pressure reduction in delaying CKD progression, little is known about the benefits of modest population-wide decrements in blood pressure on incident CKD. Methods: We used multivariable linear regression to estimate incidence rate differences comparing the impact of 2 pragmatic hypothetical interventions to reduce the incidence of CKD: (1) a population-wide intervention that reduced systolic blood pressure by 1 mmHg and (2) targeted interventions that reduced the prevalence of unaware, untreated, or uncontrolled blood pressure above goal (as defined by Joint National Committee (JNC) 7 and JNC 8 thresholds) by 10%. The population comprised 15,390 participants of the Atherosclerosis Risk in Communities Study (45-64 years of age at baseline, 1987-1989). Incident CKD was ascertained from laboratory assays and abstraction of medical records. Results: Over a mean of 20 years of follow up, 3,852 incident CKD events were ascertained. After adjustment for antihypertensive use, gender, diabetes, and age a 1 mmHg decrement in SBP across the total population was associated with an estimated 11.7 and 13.4 fewer incident CKD events per 100,000 person-years (PY) in African Americans and white Americans, respectively. Among participants with blood pressure above JNC 7 goal, a 10% decrease in unaware, untreated, or uncontrolled blood pressure was associated with 3.2, 2.8 and 5.8 fewer incident CKD events per 100,000 PY in African Americans and 3.1, 0.7, and 1.0 fewer incident CKD per 100,000 PY in white Americans. Interventions targeted to the population with blood pressure above JNC 7 goal produced greater reductions in incident CKD than interventions targeted at reductions in blood pressure above JNC 8 treatment goal. Extrapolation to the US African American and white American populations age greater than 45 years (NHANES 2010) suggests that a 1 mmHg decrement in SBP could result in approximately 9,996 fewer incident CKD events annually compared to approximately 2,098, 636, and 1,598 fewer incident CKD events potentially preventable from 10% decreases in unaware, untreated, and uncontrolled blood pressure above goal. Conclusions: Modest blood pressure interventions population-wide provide an opportunity to substantially reduce the burden of incident CKD. Among the high-risk population, lowering the threshold for blood pressure treatment to JNC 7’s treatment goal could increase the impact of high-risk strategies on CKD prevention when compared to JNC 8’s treatment goal.