Kostis, William J.

Background Blood pressure ( BP ) varies over time within individual patients and across different BP measurement techniques. The effect of different BP targets on concordance between BP measurements is unknown. The goals of this analysis are to evaluate concordance between (1) clinic and ambulatory BP , (2) clinic visit‐to‐visit variability and ambulatory BP variability, and (3) first and second ambulatory BP and to evaluate whether different clinic targets affect these relationships. Methods and Results The SPRINT (Systolic Blood Pressure Intervention Trial) ambulatory BP monitoring ancillary study obtained ambulatory BP readings in 897 participants at the 27‐month follow‐up visit and obtained a second reading in 203 participants 293±84 days afterward. There was considerable lack of agreement between clinic and daytime ambulatory systolic BP with wide limits of agreement in Bland‐Altman plots of −21 to 34 mm Hg in the intensive‐treatment group and −26 to 32 mm Hg in the standard‐treatment group. Overall, there was poor agreement between clinic visit‐to‐visit variability and ambulatory BP variability with correlation coefficients for systolic and diastolic BP all <0.16. We observed a high correlation between first and second ambulatory BP ; however, the limits of agreement were wide in both the intensive group (−27 to 21 mm Hg) and the standard group (−23 to 20 mm Hg). Conclusions We found low concordance in BP and BP variability between clinic and ambulatory BP and second ambulatory BP . Results did not differ by treatment arm. These results reinforce the need for multiple BP measurements before clinical decision making.

In observational studies, left ventricular mass (LVM) and structure are strong predictors of mortality and cardiovascular events. However, the effect of hypertension treatment on LVM reduction and its relation to subsequent outcomes is unclear, particularly at lower blood pressure (BP) targets. In an ancillary study of SPRINT (Systolic Blood Pressure Intervention Trial), where participants were randomly assigned to intensive BP control (target systolic BP target <120 mm Hg) versus standard BP control (<140 mm Hg), cardiac magnetic resonance imaging was performed at baseline and 18-month follow-up to measure: LVM, volumes, ejection fraction, and native T1 mapping for myocardial fibrosis. At baseline, 337 participants were examined (age: 64±9 years, 45% women); 300 completed the 18-month exam (153 intensive control and 147 standard control). In the intensive versus standard BP control group at 18 months, there was no difference in change in LVM (mean±SE =−2.7±0.5 g versus −2.3±0.7 g; P =0.368), ejection fraction, or native T1 ( P =0.79), but there was a larger decrease in LVM/end-diastolic volume ratio (−0.04±0.01 versus −0.01±0.01; P =0.002) a measure of concentric LV remodeling. There were fewer cardiovascular events in the intensive control group, but no significant association between the reduced events and change in LVM or any other cardiac magnetic resonance imaging measure. In SPRINT-HEART, contrary to our hypothesis, there were no significant between-group differences in LVM, function, or myocardial T1 at 18-month follow-up. These results suggests that mediators other than these LV measures contribute to the improved cardiovascular outcomes with intensive BP control.

Blood pressure (BP) varies over time within individual patients and across different BP measurement techniques. The effect of different BP targets on the concordance between BP measurements is unknown. The goal of this analysis was to evaluate concordance in: 1) clinic BP and ambulatory BP, 2) clinic visit-to-visit variability and ambulatory BP variability and 3) initial and repeat ambulatory BP. We also sought to evaluate whether treatment assignment of intensive vs standard BP target affected these relationships. The Systolic Blood Pressure Intervention Trial (SPRINT) ambulatory blood pressure monitoring ancillary study obtained ambulatory BP readings in 897 SPRINT participants at the 27 month follow up visit and 203 consecutive repeat ambulatory BP readings taken an average of 9.8 months later. There was poor agreement between clinic systolic BP and daytime ambulatory systolic BP (limits of agreement in Bland-Altman plots of -21 to 34 mm Hg in the intensive treatment group and -26 to 32 mm Hg in the standard treatment group). There was poor agreement between clinic visit-to-visit variability (coefficient of variation) and ambulatory BP variability (coefficient of variation of a 24 hr ambulatory BP) with correlation coefficients for systolic BP <0.16. While there was a high correlation between ambulatory BP at 27 months and repeat ambulatory BP (r ~0.56), there was significant variability between repeat ambulatory BP assessments (limits of agreement of -27 to 21 mm Hg in the intensive group and -23 to 20 mm Hg in the standard group). In conclusion, irrespective of treatment target, we found low concordance in BP and BP variability between clinic BP and ambulatory BP, and additionally between repeat ambulatory BP assessments. These results reinforce the need for multiple guideline adherent BP measurements prior to clinical decision making.

Intensive systolic blood pressure (SBP) control improved outcomes in SPRINT (Systolic Blood Pressure Intervention Trial). Our objective was to expand on reported findings by analysis of baseline characteristics, primary outcomes, adverse events, follow-up blood pressure, and medication use differences by baseline SBP (tertile 1 [T1], <132; tertile 2 [T2], 132–145; and tertile 3 [T3], >145 mm Hg). Participants with higher baseline SBP tertile were more often women and older, had higher cardiovascular risk, and lower utilization of antihypertensive medications, statins, and aspirin. Achieved SBP in both treatment arms was slightly higher in T2 and T3 compared with T1 and fewer in the T3 groups achieved SBP targets compared with T1 and T2 groups. The primary composite outcome with intensive versus standard SBP treatment was reduced by 30% in T1, 23% in T2, and 17% in T3 with no evidence of an interaction ( P =0.77). Event rates were lower in the intensive arm, and there was no evidence that this benefit differed by SBP tertile. There was no difference in the hazard for serious adverse events in any of the 3 tertiles. Medication utilization differed across the SBP tertiles at baseline with a lesser percentage of diuretics and angiotensin-converting enzyme inhibitors/angiotensin receptor blocker drugs in the higher tertiles—a finding that reversed during the trial. The beneficial effects of intensive SBP lowering were not modified by the level of baseline SBP. Within the parameters of this population, these findings add support for clinicians to treat blood pressure to goal irrespective of baseline SBP.