BP Measurement in Clinical Practice: Time to SPRINT to Guideline-Recommended Protocols Paul E. Drawz1 and Joachim H. Ix2 1 Division of Renal Diseases and Hypertension, University of Minnesota, Minneapolis, Minnesota; and 2 Division of Nephrology-Hypertension, University of California, San Diego, San Diego, California ABSTRACT Hypertension is the leading chronic disease risk factor in the world and is especially important in patients with CKD, nearly 90% of whom have hypertension. Recently, in the Systolic BP Intervention Trial (SPRINT), intensive lowering of clinic systolic BP to a target ,120 mm Hg, compared with a standard BP target of ,140 mm Hg, reduced risk for cardiovascular disease and all-cause mortality. However, because BP was measured unobserved using an automated device, some investigators have questioned the ability to translate SPRINT results into routine clinical practice, in which measurement of BP is typically less standardized. In this review, we discuss the BP measurement techniques used in major observational studies and clinical trials that form the evidence base for our current approach to treating hypertension, evaluate the effect of measurement technique on BP readings, and explore how ambulatory BP data from the SPRINT trial may inform this discussion. We conclude by arguing for implementation of guideline-recommended BP measurement techniques in routine clinical practice. J Am Soc Nephrol 29: 383–388, 2018. doi: Recently, in the Systolic BP Intervention Trial (SPRINT), among hypertensive patients with and without CKD, intensive lowering of systolic BP to a target ,120 mm Hg reduced risk for cardiovascular disease (CVD) and all-cause mortality compared with a standard BP target of ,140 mm Hg. Results were similar in those with and without CKD.1 Some have questioned the ability to translate the results into clinical practice because BP was measured with an automated monitor and a protocol on the basis of recommendations from the American Heart Association (AHA), which are not done routinely in many clinical practices.2,3 The purpose of this review is to discuss the BP measurement techniques utilized in prior large observational studies and clinical trials that form the evidence base for our current approach to treating hypertension, to review the effect of nonstandardized BP measurement technique, and to describe ambulatory BP data from a subset of SPRINT participants which may inform this discussion and facilitate translation of SPRINT findings into clinical practice. SPRINT randomly assigned 9261 patients at high cardiovascular risk to intensive treatment (systolic BP target ,120 mm Hg) or standard treatment (,140 mm Hg).1 SPRINT specifically oversampled persons with CKD—2646 (30%) participants had CKD at baseline. After a median follow-up of 3.3 years, the trial was stopped early. Intensive treatment was associated with a substantial reduction in the primary cardiovascular outcome (hazard ratio [HR], 0.75; 95% confidence interval [95% CI], 0.64 to 0.89) as well as all-cause mortality (HR, 0.73; 95% CI, 0.60 to 0.90). Importantly for nephrologists, results were similar in those with and without CKD; there was a similar effect size and direction for the effect of intensive BP treatment for the primary CVD outcome in the CKD and non-CKD subgroups (interaction P value was 0.36). Likely because of lower statistical power in the CKD subset, the association of randomization to intensive BP control with CVD did not reach statistical significance in the CKD subset alone (HR, 0.81; 95% CI, 0.63 to 1.05).4 On the other hand, even within the CKD subset, intensive BP control was associated with lower risk of all-cause mortality (HR, 0.72; 95% CI, 0.53 to 0.99).4 The two previous trials evaluating different BP targets in patients with CKD, the African American Study of Kidney Disease and Hypertension (AASK) and Modification of Diet in Renal Disease (MDRD), had renal outcomes as their primary end points, and did not examine CVD events.5,6 It should be noted that SPRINT participants with CKD were at high cardiovascular risk but lower risk for progression of CKD with lower proteinuria and only mild-to-moderate decreased eGFR compared with AASK and Published online ahead of print. Publication date available at www.jasn.org. Correspondence: Dr. Paul E. Drawz, Division of Renal Diseases and Hypertension, University of Minnesota, 717 Delaware Street SE, Suite 353, Minneapolis, MN 55414. Email: draw0003@umn.edu Copyright © 2018 by the American Society of Nephrology J Am Soc Nephrol 29: 383–388, 2018 ISSN : 1046-6673/2902-383 383 MDRD participants. These aspects of the trial design are reflected in the low rates of renal events (decrease in eGFR of 50% or more or development of ESRD for patients with CKD at baseline) in SPRINT participants with CKD at baseline; only 29 of 2646 CKD participants experienced this composite end point and only 16 required dialysis.1 As mentioned in the introduction, the BP measurement protocol outlined in the SPRINT Manual of Procedures was on the basis of