Low on-treatment diastolic blood pressure and cardiovascular outcome: A post-hoc analysis using NHLBI SPRINT Research Materials

Abstract

Recent studies including the SPRINT trial have shown beneficial effects of intensive systolic blood pressure reduction over the standard approach. The awareness of the J-curve for diastolic blood pressure (DBP) causes some uncertainty regarding the net clinical effects of blood pressure reduction. The current analysis was performed to investigate effects of low on-treatment DBP on cardiovascular risk in the SPRINT population. The primary composite outcome was the occurrence of myocardial infarction, acute coronary syndrome not resulting in myocardial infarction, stroke, acute decompensated heart failure or death from cardiovascular causes. The prevalence of primary outcomes was significantly higher in subjects within low DBP in both standard (44–67 mmHg [10.8%] vs 67–73 mmHg [6.7%] vs 73–78 mmHg [5.1%] vs 78–83 mmHg [4.4%] vs 83–113 mmHg [4.3%], p < 0.001) and intensive treatment (38–61 mmHg [6.7%] vs 61–66 mmHg [4.1%] vs 66–70 mmHg [4.5%] vs 70–74 mmHg [2.7%] vs 74–113 mmHg [3.4%], p < 0.001) arms. After adjusting for covariates, low DBP showed no significant effects on cardiovascular risk. Therefore, while reaching blood pressure targets, low DBP should not be a matter of concern.

Not afraid of low diastolic blood pressure anymore?

“…Ongoing analysis of SPRINT findings has indicated that the increased cardiovascular risk in for participants with a low DBP may be explained by factors other than simply the DBP, such as higher age and higher prevalence of cardiovascular or chronic kidney disease. This suggests that a low DBP is not an independent risk factor for cardiovascular events [3,4]. This also seems to be the case in other studies of subjects with high cardiovascular risk [5].…”

Unsolved Problem: (Isolated) Systolic Hypertension with Diastolic Blood Pressure below the Safety Margin

“…It was optimal for investigating the relationship between low dBP and mortality risk because all patients had both HTN and stable (chronic) CAD. J-curve association was found between dBP and primary outcome; patients with a dBP < 75 mm Hg had a higher risk of acute MI and death [33,39]. The primary outcome was twice as prevalent with a dBP < 70 mm Hg and 4 times as prevalent with a dBP < 60 mm Hg [13].…”

“…The target dBP was ≤90 mm Hg in 6,264 patients, ≤85 mm Hg also in 6,264 patients, and ≤80 mm Hg in 6,262 patients. In these arms, no significant difference was found in total and cardiovascular (CV) mortality, MI, and stroke risk [32,33]. Nevertheless, there is a confirmation of J-curve between major adverse CV events (MACE) and dBP using additional data about MI (all plus the silent ones) [34].…”

“…For example, if in-treatment dBP fell to < 55 mm Hg, the risk was 68% higher (p = 0.006) than with a dBP of 55-90 mm Hg regardless of prior CVD. Sobieraj et al [33] published an analysis of 8,890 patients from the SPRINT trial database. They reported a J-shaped curve regarding in-treatment dBP in hypertensive patients with prior CVD.…”

Use of advanced statistical techniques to predict all-cause mortality in the Systolic Blood Pressure Intervention Trial

“…Sobieraj et al. examining the SPRINT database reported that there were adverse effects or a J curve low on-treatment diastolic blood pressure on cardiovascular risk in the SPRINT population and that after adjusting for covariates, low diastolic blood pressure showed no significant effects on cardiovascular risk [ 19 , 20 , 21 ]. These authors did not report on all-cause mortality.…”