Influence of Baseline Diastolic Blood Pressure on the Effects of Intensive Systolic Blood Pressure Lowering on the Risk of Stroke

Intensive Blood Pressure Lowering in Individuals With Low Diastolic Blood Pressure and Elevated Troponin Levels in SPRINT

BACKGROUND

Among individuals with hypertension and low diastolic blood pressure (DBP), the optimal BP target remains controversial due to concerns that BP lowering may reduce coronary perfusion. We determined the impact of intensive BP control among individuals with elevated systolic BP who have low DBP and elevated hs-cTnT (high-sensitivity cardiac troponin T) levels.

METHODS AND RESULTS

A total of 8828 participants in SPRINT (Systolic Blood Pressure Intervention Trial) were stratified by baseline DBP. Those with low DBP (<70 mm Hg) were further stratified by elevated hs-cTnT (≥14 ng/L) at baseline. The effects of intensive versus standard BP lowering on a cardiovascular disease composite end point, all-cause death, and 1-year change in hs-cTnT were determined. The combination of low DBP/high hs-cTnT was independently associated with a higher risk for cardiovascular disease and all-cause death, as well as greater 1-year increases in hs-cTnT, compared with DBP ≥70 mm Hg. However, randomization to intensive versus standard BP lowering led to similar reductions in cardiovascular disease risk among individuals with low DBP/high hs-cTnT (hazard ratio [HR], 0.82 [95% CI, 0.57-1.19]), low DBP/low hs-cTnT (HR, 0.48 [95% CI, 0.29-0.79]), and DBP ≥70 mm Hg (HR, 0.73 [95% CI, 0.60-0.89]; P for interaction=0.20). Intensive BP lowering also led to a reduction in all-cause death that was similar across groups (P for interaction=0.57).

CONCLUSIONS

In this nonprespecified subgroup analysis of SPRINT, individuals with low DBP and elevated hs-cTnT, low DBP and nonelevated hs-cTnT, and DBP ≥70 mm Hg derived similar cardiovascular disease and mortality benefits from intensive BP lowering. These findings warrant confirmation in other studies.

Low diastolic blood pressure and adverse outcomes in inpatients with acute exacerbation of chronic obstructive pulmonary disease: A multicenter cohort study

BACKGROUND

Although intensively studied in patients with cardiovascular diseases (CVDs), the prognostic value of diastolic blood pressure (DBP) has little been elucidated in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). This study aimed to reveal the prognostic value of DBP in AECOPD patients.

METHODS

Inpatients with AECOPD were prospectively enrolled from 10 medical centers in China between September 2017 and July 2021. DBP was measured on admission. The primary outcome was all-cause in-hospital mortality; invasive mechanical ventilation and intensive care unit (ICU) admission were secondary outcomes. Least absolute shrinkage and selection operator (LASSO) and multivariable Cox regressions were used to identify independent prognostic factors and calculate the hazard ratio (HR) and 95% confidence interval (CI) for adverse outcomes.

RESULTS

Among 13,633 included patients with AECOPD, 197 (1.45%) died during their hospital stay. Multivariable Cox regression analysis showed that low DBP on admission (<70 mmHg) was associated with increased risk of in-hospital mortality (HR = 2.16, 95% CI: 1.53-3.05, Z = 4.37, P <0.01), invasive mechanical ventilation (HR = 1.65, 95% CI: 1.32-2.05, Z = 19.67, P <0.01), and ICU admission (HR = 1.45, 95% CI: 1.24-1.69, Z = 22.08, P <0.01) in the overall cohort. Similar findings were observed in subgroups with or without CVDs, except for invasive mechanical ventilation in the subgroup with CVDs. When DBP was further categorized in 5-mmHg increments from <50 mmHg to ≥100 mmHg, and 75 to <80 mmHg was taken as reference, HRs for in-hospital mortality increased almost linearly with decreased DBP in the overall cohort and subgroups of patients with CVDs; higher DBP was not associated with the risk of in-hospital mortality.

CONCLUSION

Low on-admission DBP, particularly <70 mmHg, was associated with an increased risk of adverse outcomes among inpatients with AECOPD, with or without CVDs, which may serve as a convenient predictor of poor prognosis in these patients.

CLINICAL TRIAL REGISTRATION

Chinese Clinical Trail Registry, No. ChiCTR2100044625.

Diastolic Blood Pressure and Intensive Blood Pressure Control on Cognitive Outcomes: Insights From the SPRINT MIND Trial

BACKGROUND

The potential benefits or harms of intensive systolic blood pressure (BP) control on cognitive function and cerebral blood flow in individuals with low diastolic blood pressure (DBP) remain unclear.

METHODS

We conducted a post hoc analysis of the SPRINT MIND (Systolic Blood Pressure Intervention Trial Memory and Cognition in Decreased Hypertension) that randomly assigned hypertensive participants to an intensive (<120 mm Hg; n=4278) or standard (<140 mm Hg; n=4385) systolic blood pressure target. We evaluated the effects of BP intervention on cognitive outcomes and cerebral blood flow across baseline DBP quartiles.

RESULTS

Participants in the intensive group had a lower incidence rate of probable dementia or mild cognitive impairment than those in the standard group, regardless of DBP quartiles. The hazard ratio of intensive versus standard target for probable dementia or mild cognitive impairment was 0.91 (95% CI, 0.73-1.12) in the lowest DBP quartile and 0.70 (95% CI, 0.48-1.02) in the highest DBP quartile, respectively, with an interaction P value of 0.24. Similar results were found for probable dementia (interaction P=0.06) and mild cognitive impairment (interaction P=0.80). The effect of intensive treatment on cerebral blood flow was not modified by baseline DBP either (interaction P=0.25). Even among participants within the lowest DBP quartile, intensive versus standard BP treatment resulted in an increasing trend of annualized change in cerebral blood flow (+0.26 [95% CI, -0.72 to 1.24] mL/[100 g·min]).

CONCLUSIONS

Intensive BP control did not appear to have a detrimental effect on cognitive outcomes and cerebral perfusion in patients with low baseline DBP.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT01206062.

Superior stroke prevention with angiotensin receptor blockers compared with other antihypertensive drugs

INTRODUCTION

Stroke is a major cause of death and disability and its incidence is linearly increased with the elevation of blood pressure (BP) and the advancement of age in both men and women, with its incidence being higher in older subjects, the blacks and women.

AREAS COVERED

The annual worldwide incidence of stroke is 7.6 million for subjects ≥ 20 years of age with the average direct and indirect annual costs of stroke care, is expected to be $94.3 billion between 2014 and 2015. With respect to the cause of stroke, this is multifactorial, due to atherosclerotic heart disease, inflammation, atrial fibrillation, and hypertension with the latter being the most important cause. Therefore, control of BP is the major factor for its prevention. In order to get a better perspective on the current management of stroke, a Medline search of the English literature was conducted between 2014 and 2022 and 26 pertinent papers were selected.

EXPERT OPINION

Review of data from the selected papers demonstrated that control of SSBP < 130 mmHg was better in stroke prevention than SBP 130-140 mmHg for primary and secondary strokes. Among the drugs used, angiotensin receptor blockers provided superior stroke prevention compared to angiotensin converting enzyme inhibitors and other antihypertensive drugs.

Answering Clinical Questions Using Machine Learning: Should We Look at Diastolic Blood Pressure When Tailoring Blood Pressure Control?

Background: The guidelines recommend intensive blood pressure control. Randomized trials have focused on the relevance of the systolic blood pressure (SBP) lowering, leaving the safety of the diastolic blood pressure (DBP) reduction unresolved. There are data available which show that low DBP should not stop clinicians from achieving SBP targets; however, registries and analyses of randomized trials present conflicting results. The purpose of the study was to apply machine learning (ML) algorithms to determine, whether DBP is an important risk factor to predict stroke, heart failure (HF), myocardial infarction (MI), and primary outcome in the SPRINT trial database. Methods: ML experiments were performed using decision tree, random forest, k-nearest neighbor, naive Bayesian, multi-layer perceptron, and logistic regression algorithms, including and excluding DBP as the risk factor in an unselected and selected (DBP < 70 mmHg) study population. Results: Including DBP as the risk factor did not change the performance of the machine learning models evaluated using accuracy, AUC, mean, and weighted F-measure, and was not required to make proper predictions of stroke, MI, HF, and primary outcome. Conclusions: Analyses of the SPRINT trial data using ML algorithms imply that DBP should not be treated as an independent risk factor when intensifying blood pressure control.