Blood pressure variability in subacute stage and risk of major vascular events in ischemic stroke survivors

Long-term blood pressure variability and risk of cardiovascular diseases in populations with different blood pressure status: an ambispective cohort study

OBJECTIVE

We aimed to investigate the correlation between long-term blood pressure variability (BPV) and the risk of cardiovascular diseases (CVDs) among population with different blood pressure statuses (normotension, well-controlled hypertension, and uncontrolled hypertension).

METHODS

In this ambispective cohort study, CVD-free residents aged over 50 years were consecutively enrolled from two community health service centers (CHCs) in Tianjin, China from April 2017 to May 2017. Information on blood pressure was retrospectively extracted from electronic medical records of CHCs between January 2010 and May 2017, and the occurrence of new-onset CVDs was prospectively observed during follow-up until September 2019. Long-term variation of SBP and DBP was assessed using four indicators: SD, coefficient of variation (CV), average successive variability (ASV), and average real variability (ARV). Cox proportional hazards regression model was developed to identify the potential impact of BPV on the incidence of CVDs. The receiver operating characteristic curve (ROC) was utilized to evaluate the predictive value of BPV indicators for the occurrence of CVDs.

RESULTS

Of 1275 participants included, 412 (32.3%) experienced new CVD events during the median 7.7 years of follow-up, with an incidence density of 499/10 000 person-year in the whole cohort. Cox regression analysis revealed that almost all SBP and DBP variability indicators (except for SBP-SD) were significantly related to the risk of CVDs, especially among individuals with well-controlled hypertension. A trend toward an increased risk of CVDs across BPV quartiles was also observed. Moderate predictive abilities of BPV were observed, with the area under ROC curves ranging between 0.649 and 0.736. For SBP variability, SD had the lowest predictive ability, whereas for DBP variability, ARV had the lowest predictive ability. No significant association of CVDs with SBP-SD was found in all analyses, no matter as a continuous or categorical variable.

CONCLUSION

Elevated long-term BPV is associated with an increased risk of CVDs, especially among individuals with well-controlled hypertension. CV and ASV had higher predictive values than SD and ARV.

Relationship of Day-by-Day Blood Pressure Variability and Admission Stroke Severity in Acute Ischemic Stroke

OBJECTIVES

Research on the association between stroke severity and day-by-day blood pressure variability (BPV) in acute ischemic stroke (AIS) is rare as the majority focus on the blood pressure (BP) or the short-term BPV. Our study aims to explore the exact roles of daily BPV through the 7-day commencement on stroke severity in AIS.

METHODS

The study included 633 patients with AIS, defining AIS as the time from the beginning of symptom up to 7 days with recording BP twice a day as well as calculating the daily BPV, and then matching them to the stroke severity. The logistic regression models were used to evaluate associations between stroke severity and day-by-day BPV. We used the smooth curve fitting to identify whether there was a nonlinear association. In addition, the subgroup analyses were performed using the logistic regression.

RESULTS

According to the modified National Institutes of Health Stroke Scale score, 301 (47.5%) patients were allocated to the mild stroke group and 332 (52.5%) to the moderate-to-severe stroke group. In terms of stroke categories, we found no significant difference between BP at admission or mean BP. However, the moderate-to-severe stroke group exhibited higher daily BPV. The multiple logistic regression analysis indicated that day-by-day BPV was positively correlated to stroke severity [odds ratio (OR)=1.05, 95% CI:1.01-1.1, P =0.03 for SBP-SD; OR=1.08, 95% CI:1.01-1.15, P =0.03 for SBP-CV; OR=1.04, 95% CI:1.01-1.07, P =0.015 for SBP-SV).

CONCLUSIONS

High day-by-day BPV in AIS was associated with more severe stroke independent of BP levels.

Stroke Related Brain-Heart Crosstalk: Pathophysiology, Clinical Implications, and Underlying Mechanisms

The emergence of acute ischemic stroke (AIS) induced cardiovascular dysfunctions as a bidirectional interaction has gained paramount importance in understanding the intricate relationship between the brain and heart. Post AIS, the ensuing cardiovascular dysfunctions encompass a spectrum of complications, including heart attack, congestive heart failure, systolic or diastolic dysfunction, arrhythmias, electrocardiographic anomalies, hemodynamic instability, cardiac arrest, among others, all of which are correlated with adverse outcomes and mortality. Mounting evidence underscores the intimate crosstalk between the heart and the brain, facilitated by intricate physiological and neurohumoral complex networks. The primary pathophysiological mechanisms contributing to these severe cardiac complications involve the hypothalamic-pituitary-adrenal (HPA) axis, sympathetic and parasympathetic hyperactivity, immune and inflammatory responses, and gut dysbiosis, collectively shaping the stroke-related brain-heart axis. Ongoing research endeavors are concentrated on devising strategies to prevent AIS-induced cardiovascular dysfunctions. Notably, labetalol, nicardipine, and nitroprusside are recommended for hypertension control, while β-blockers are employed to avert chronic remodeling and address arrhythmias. However, despite these therapeutic interventions, therapeutic targets remain elusive, necessitating further investigations into this complex challenge. This review aims to delineate the state-of-the-art pathophysiological mechanisms in AIS through preclinical and clinical research, unraveling their intricate interplay within the brain-heart axis, and offering pragmatic suggestions for managing AIS-induced cardiovascular dysfunctions.

Association between High-Sensitivity C-Reactive Protein and Blood Pressure Variability in Subacute Stage of Ischemic Stroke

The determinants of blood pressure variability (BPV) are complex. We aimed to evaluate whether circulating high-sensitivity C-reactive protein (hsCRP) is associated with short-term BPV during the subacute stage of ischemic stroke. In this observational study, a consecutive series of acute ischemic stroke patients who underwent 24 h ambulator blood pressure monitoring (ABPM) during day 4 to 10 after onset were enrolled. Multivariable linear regression models were constructed to assess relationships between hsCRP and BPV. Among a total of 325 patients analyzed, the mean age was 60 years old and 72% were male. The SD, CV, ARV of 24 h SBP and DBP were more likely to be higher in patients with hsCRP ≥ 2 mg/L, and these predispositions remained unchanged in linear regression analyses after adjusting for possible confounding factors, with a dose-response relationship when patients were additionally categorized into quartiles according to hsCRP levels using the lowest quartile as a reference category. In contrast, similar results were observed for the mean of SBP but not the mean of DBP. These results indicate that hsCRP is dose-dependently associated with short-term BPV during the subacute stage of ischemic stroke. These findings suggested that patients with a higher level of hsCRP tended to have larger blood pressure fluctuations.

Daily blood pressure variability in relation to neurological functional outcomes after acute ischemic stroke

Background

Prior research has shown inconclusive findings regarding the relationship between blood pressure variability (BPV) in acute ischemic stroke (AIS) and functional outcomes. Most research has examined the connection between short-term BPV during the early 24-72 h after the occurrence of ischemic stroke and functional prognosis. We sought to determine the relationship between daily BPV at 7 days of commencement and functional outcomes during the 3 months following AIS.

Methods

Altogether, 633 patients with AIS admitted within 72 h of commencement were enrolled. AIS was defined as the time from the onset of symptoms to 7 days. Throughout this period, blood pressure (BP) was recorded twice daily (casual BP cuffs). The daily BPV, with standard deviation (SD) and coefficient of variation (CV), was calculated and matched to the functional results. The adverse outcome was characterized as a modified Rankin scale (mRS)≥3, which comprised the recurrence of stroke, clinical intracranial bleeding, and death.

Results

In total, 633 participants were included, and the incidence of adverse outcomes was 14.06% (89/633). There was a significant positive correlation between daily BPV and adverse outcomes but not between mean BP and risk. Smooth curve fitting revealed a U-shaped connection between the mean BP and adverse clinical outcomes. Multivariable logistic regression analysis showed an independent correlation between daily BPV and an adverse outcome in the top vs. bottom quartile of systolic BPV (odds ratio [OR] = 2.4, 95% confidence interval [CI]: 1.17-4.96, P = 0.018 for SD; OR = 2.4, 95% CI: 1.17-4.93, P = 0.017 for CV) during a 3-month follow-up period. Identical results have been reported for diastolic BPV.

Conclusion

Irrespective of BP level, elevated daily systolic BPV and diastolic BPV in AIS were associated with an increased risk of adverse outcomes within 3 months. We also discovered a U-shaped association between the mean BP and adverse clinical outcomes. These findings suggested that BPV should be a risk factor for adverse outcomes after ischemic stroke, which provided new insight into BP management strategy.

Day-by-Day Blood Pressure Variability in the Subacute Stage of Ischemic Stroke and Long-Term Recurrence

BACKGROUND AND PURPOSE

This study aimed to determine whether variability of day-by-day blood pressure (BP) during the subacute stage of acute ischemic stroke is predictive of long-term stroke recurrence.

METHODS

We analyzed 7665 patients (mean±SD age: 72.9±13.1 years; women: 42.4%) hospitalized for first-ever ischemic stroke in 7 stroke centers in Fukuoka, Japan, from June 2007 to November 2018. BP was measured daily during the subacute stage (4-10 days after onset). Its mean and coefficient of variation (CV) values were calculated and divided into 4 groups according to the quartiles of these BP parameters. Patients were prospectively followed up for recurrent stroke or all-cause death. The cumulative event rate was calculated with the Kaplan-Meier method. We estimated the hazard ratios and 95% confidence intervals of the events of interest after adjusting for potential confounders and mean BP values using Cox proportional hazards models. The Fine-Gray model was also used to account for the competing risk of death.

RESULTS

With a mean (±SD) follow-up duration of 3.9±3.2 years, the rates of recurrent stroke and all-cause death were 3.9 and 9.9 per 100 patient-years, respectively. The cumulative event rates of recurrent stroke and all-cause death increased with increasing CVs of systolic BP and diastolic BP. The systolic BP CV was significantly associated with an increased risk of recurrent stroke after adjusting for multiple confounders and mean BP (hazard ratio [95% CI] for fourth quartile versus first quartile, 1.26 [1.05-1.50]); the risk of recurrent stroke also increased with an increasing systolic BP CV for nonfatal strokes (1.26 [1.05-1.51]) and when death was regarded as a competing risk (1.21 [1.02-1.45]). Similar associations were observed for the diastolic BP CV.

CONCLUSIONS

Day-by-day variability of BP during the subacute stage of acute ischemic stroke was associated with an increased long-term risk of recurrent stroke.

Blood Pressure Level and Variability During Long-Term Prasugrel or Clopidogrel Medication After Stroke: PRASTRO-I

BACKGROUND AND PURPOSE

High blood pressure increases bleeding risk during treatment with antithrombotic medication. The association between blood pressure levels and the risk of recurrent stroke during long-term secondary stroke prevention with thienopyridines (particularly prasugrel) has not been well studied.

METHODS

This was a post hoc analysis of the randomized, double-blind, multicenter PRASTRO-I trial (Comparison of Prasugrel and Clopidogrel in Japanese Patients With Ischemic Stroke-I). Patients with noncardioembolic stroke were randomly assigned (1:1) to receive prasugrel 3.75 mg/day or clopidogrel 75 mg/day for 96 to 104 weeks. Risks of any ischemic or hemorrhagic stroke, combined ischemic events, and combined bleeding events were determined based on the mean level and visit-to-visit variability, including successive variation, of systolic blood pressure (SBP) throughout the observational period. These risks were also compared between quartiles of mean SBP level and successive variation of SBP.

RESULTS

A total of 3747 patients (age 62.1±8.5 years, 797 women), with a median average SBP level during the observational period of 132.5 mm Hg, were studied. All the risks of any stroke (146 events; hazard ratio, 1.318 [95% CI, 1.094-1.583] per 10-mm Hg increase), ischemic stroke (133 events, 1.219 [1.010-1.466]), hemorrhagic stroke (13 events, 3.247 [1.660-6.296]), ischemic events (142 events, 1.219 [1.020-1.466]), and bleeding events (47 events, 1.629 [1.172-2.261]) correlated with increasing mean SBP overall. Similarly, an increased risk of these events correlated with increasing successive variation of SBP (hazard ratio, 3.078 [95% CI, 2.220-4.225] per 10-mm Hg increase; 3.051 [2.179-4.262]; 3.276 [1.172-9.092]; 2.865 [2.042-4.011]; 2.764 [1.524-5.016], respectively). Event rates did not differ between the clopidogrel and prasugrel groups within each quartile of SBP or successive variation of SBP.

CONCLUSIONS

Both high mean SBP level and high visit-to-visit variability in SBP were significantly associated with the risk of recurrent stroke during long-term medication with either prasugrel or clopidogrel after stroke. Control of hypertension would be important regardless of the type of antiplatelet drugs. Registration: URL: https://www.clinicaltrials.jp; Unique identifier: JapicCTI-111582.