Association of systolic blood pressure variability with remote ischemic conditioning in acute ischemic stroke.

Systolic blood pressure variability (SBPV) is associated with outcome in acute ischemic stroke. Remote ischemic conditioning (RIC) has been demonstrated to be effective in stroke and may affect blood pressure. Relationship between SBPV and RIC treatment after stroke warrants investigation. A total of 1707 patients from per-protocol analysis set of RICAMIS study were included. The SBPV was calculated based on blood pressure measured at admission, Day 7, and Day 12. (I) To investigate the effect of SBPV on efficacy of RIC in stroke, patients were divided into High and Low categories in each SBPV parameter. Primary outcome was excellent functional outcome at 90 days. Compared with Control, efficacy of RIC in each category and interaction between categories were investigated. (II) To investigate the effect of RIC treatment on SBPV, SBPV parameters were compared between RIC and Control groups. Compared with Control, a higher likelihood of primary outcome in RIC was found in high category (max-min: adjusted risk difference [RD] = 7.2, 95% CI 1.2-13.1, P = 0.02; standard deviation: adjusted RD = 11.5, 95% CI 1.6-21.4, P = 0.02; coefficient of variation: adjusted RD = 11.2, 95% CI 1.4-21.0, P = 0.03). Significant interaction of RIC on outcomes were found between High and Low standard deviations (adjusted P < 0.05). No significant difference in SBPV parameters were found between treatment groups. This is the first report that Chinese patients with acute moderate ischemic stroke and presenting with higher SBPV, who were non-cardioemoblic stroke and not candidates for intravenous thrombolysis or endovascular therapy, would benefit more from RIC with respect to functional outcomes at 90 days, but 2-week RIC treatment has no effect on SBPV during hospital.

Under pressure: A systematic review of the association between blood pressure variability with depression and anxiety.

Blood pressure variability (BPV) impacts brain health by influencing brain structure and cerebrovascular pathologies, though the mechanisms are poorly understood. Changes in the cerebrovasculature may lead to late-onset depression, cognitive impairment, and dementia, however the relationship between BPV with depression and anxiety remains unclear, due to methodological differences and inconsistencies in past research. This review aims to clarify the association between BPV with depression and anxiety in adults to inform understandings of the mechanisms implicating BPV in cognitive health. A systematic search from inception through to January 2024 was performed on Embase, PubMed, PsycINFO, and Web of Science. Studies that assessed BPV quantified by beat-to-beat, 24-hour, or visit-to-visit were eligible if the standardised assessment of depression and/or anxiety were reported as a linear association, or mean differences across control and affect groups. A total of 14 articles reporting on 13 samples and N = 5055 persons met the inclusion criteria (median female proportion = 61 %, range 0 % - 76 %). A meta-analysis was not possible due to methodological heterogeneity in BPV measurements and metrics across studies. Mixed results were observed across depression studies with inconsistencies and variation in the direction, strength of association, and BPV metric. There was weak evidence from only three studies to support a linear association between systolic coefficient of variation and anxiety. Collectively, the findings contribute to understanding the association between BPV and brain health, suggesting that any relationship between BPV and brain structures critical for cognitive function are independent of depression and only modestly implicate anxiety.

Blood Pressure Variability After Non-invasive Low-level Tragus Stimulation in Acute Heart Failure.

Higher blood pressure (BP) variability (BPV) was shown to be strong predictors of poor cardiovascular outcomes in heart failure (HF). It is currently unknown if low-level tragus stimulation (LLTS) would lead to improvement in BPV in acute HF (AHF). The 22 patients with AHF (median 80 yrs, males 60%) were randomly assigned to active or sham group using an ear clip attached to the tragus (active group) or the earlobe (sham group) for 1 h daily over 5 days. In the active group, standard deviation (SD), coefficient of variation (CV) and δ in SBP were significantly decreased after LLTS (all p < 0.05). All the changes in SD, CV and δ in SBP before and after stimulation were also significantly different between active and sham groups (all p < 0.05). This proof-of-concept study demonstrates the beneficial effects of LLTS on BPV in AHF.

Potential role of blood pressure variability and plasma neurofilament light in the mechanism of comorbidity between Alzheimer's disease and cerebral small vessel disease.

INTRODUCTION: Long-term blood pressure variability (BPV) and plasma neurofilament light (pNfL) have been identified as potential biomarkers for Alzheimer's disease (AD) and cerebral small vessel disease (CSVD). However, the relationship between BPV, pNfL, and their association with the comorbidity of AD and CSVD remains unknown. METHODS: Participants with normal cognition and mild cognitive impairment from the Alzheimer's Disease Neuroimaging Initiative study were included in the data analysis. Linear mixed-effects regression models and causal mediation analyses were conducted to investigate the relationship among BPV, pNfL, comorbidity-related brain structural changes (hippocampal atrophy and white matter hyperintensities [WMH]), and cognitive function. RESULTS: BPV was associated with pNfL, volumes of hippocampus and WMH, and cognition. pNfL mediated the effects of BPV on brain structural changes and cognition. DISCUSSION: Our findings suggest a potential role of BPV and pNfL in the mechanism of comorbidity between AD and CSVD, underscoring the importance of BPV intervention in the general population. HIGHLIGHTS: Individuals with both Alzheimer's disease (AD) and cerebral small vessel disease (CSVD) pathologies had elevated blood pressure variability (BPV) and plasma neurofilament light (pNfL). The association between different components of BPV and brain structural changes may vary. BPV was associated with pNfL levels independent of average blood pressure. pNfL mediated the effects of BPV on comorbidity-related brain structural changes and cognitive performance.

Association between baseline blood pressure variability and left heart function following short-term extreme cold exposure.

Extreme cold exposure has been widely considered as a cardiac stress and may result in cardiac function decompensation. This study was to examine the risk factors that contribute to changes in cardiovascular indicators of cardiac function following extreme cold exposure and to provide valuable insights into the preservation of cardiac function and the cardiac adaptation that occur in real-world cold environment. Seventy subjects were exposed to cold outside (Mohe, mean temperature -17 to -34°C) for one day, and were monitored by a 24-h ambulatory blood pressure device and underwent echocardiography examination before and after extreme cold exposure. After exposure to extreme cold, 41 subjects exhibited an increase in ejection fraction (EF), while 29 subjects experienced a decrease. Subjects with elevated EF had lower baseline coefficients of variation (CV) in blood pressure compared to those in the EF decrease group. Additionally, the average real variability (ARV) of blood pressure was also significantly lower in the EF increase group. Multivariate regression analysis indicated that both baseline CV and ARV of blood pressure were independent risk factors for EF decrease, and both indicators proved effective for prognostic evaluation. Correlation analysis revealed a correlation between baseline blood pressure CV and ARV, as well as EF variation after exposure to extreme cold environment. Our research clearly indicated that baseline cardiovascular indicators were closely associated with the changes in EF after extreme cold exposure. Furthermore, baseline blood pressure variability could effectively predict alterations in left cardiac functions when individuals were exposed to extreme cold environment.

Postural orthostatic tachycardia syndrome in a Thai male patient.

Postural orthostatic tachycardia syndrome (POTS) is a heterogeneous autonomic disorder. All patients have exaggerated tachycardia upon standing, but the pathophysiology may be diverse. We present a young adult Thai male with a chief complaint of palpitations while in an upright posture since childhood. The patient underwent a modified Ewing test battery which included standing test, deep breathing, and Valsalva maneuver. His heart rate increased more than 30 beats per minute (bpm) during repeated active stand tests (65 to 110 bpm and 77 to 108 bpm), while upright diastolic blood pressure increased more than 10 mmHg. Normal Valsalva ratio (2.01 and 1.86) and baseline heart rate variability (HFRRI = 4030.24 ms2 and 643.92 ms2) indicated intact vagal function. High low-frequency systolic blood pressure variability (LFSBP = 20.93 mmHg2), increased systolic blood pressure overshoot in phase IV of Valsalva (42 mmHg), and increased upright diastolic blood pressure indicated a hyperadrenergic state. In conclusion, the overall autonomic profile was compatible with hyperadrenergic POTS. Thus, we confirmed the first male POTS case reported in Thailand. We demonstrated the importance of autonomic function testing with continuous measurements to confirm POTS. There is a need for further research in POTS in Thailand.

The impact of forced awakening on morning blood pressure surge.

BACKGROUND: Poor sleep quality can cause an increase in morning blood pressure surge (MBPS), an independent risk factor of cardiovascular disease (CVD) events. Awakening induced by external factors such as alarm clocks, may also contribute to increased MBPS. OBJECTIVES: To (1) compare the MBPS and sleep quality parameters between natural and forced awakenings and (2) examine the potential impact of forced awakening on MBPS, independent of sleep quality. METHODS: Thirty-two healthy adults participated in this pilot study, which included one night of natural awakening and one night of forced awakening (i.e., sleep was interrupted by an alarm after five hours). Objective and self-reported sleep quality parameters were measured using a multisensory wristband and sleep diaries, respectively, and beat-to-beat blood pressure variability was assessed using a continuous blood pressure monitor. Analyses included a paired t-test (objective 1) and linear mixed models (objective 2). RESULTS: Participants predominantly consisted of young, healthy, and highly educated Asian adults. During the night of sleep with forced awakening, significantly higher MBPS, lower objective wakefulness after sleep onset, and lower self-reported sleep latency were observed, compared to the night with natural awakening. Forced awakening was significantly associated with increased MBPS after controlling for age, sex, mean arterial pressure, and sleep quality. CONCLUSIONS: Forced awakening may significantly increase MBPS, consequently heightening the risk of CVD events. Study findings should be validated in a larger sample. Further research is also warranted to examine the impact of forced awakening on MBPS in individuals with CVD.

Long-Term Visit-to-Visit Blood Pressure Variability and Cognitive Decline Among Patients With Hypertension: A Pooled Analysis of 3 National Prospective Cohorts.

BACKGROUND: A limited number of studies investigated the association between blood pressure variability (BPV) and cognitive impairment in patients with hypertension. This study aimed to identify the longitudinal association between BPV and cognitive decline and the role of blood pressure (BP) control in this association. METHODS AND RESULTS: Participants with hypertension from the HRS (Health and Retirement Study), the ELSA (English Longitudinal Study of Ageing), and the CHARLS (China Health and Retirement Longitudinal Study) were included. Variation independent of the mean (VIM) was adopted to measure BPV. Cognitive function was measured by standard questionnaires, and a standardized Z score was calculated. Linear mixed-model and restricted cubic splines were adopted to explore the association between BPV and cognitive decline. The study included 4853, 1616, and 1432 eligible patients with hypertension from the HRS, ELSA, and CHARLS, respectively. After adjusting for covariates, per-SD increment of VIM of BP was significantly associated with global cognitive function decline in Z scores in both systolic BP (pooled ß, -0.045 [95% CI, -0.065 to -0.029]) and diastolic BP (pooled ß, -0.022 [95% CI, -0.040 to -0.004]) among hypertensive patients. Similar inverse associations were observed in patients with hypertension taking antihypertensive drugs and in patients with hypertension with well-controlled BP. CONCLUSIONS: High BPV was independently associated with a faster cognitive decline among patients with hypertension, even those with antihypertensive medications or well-controlled BP. Further studies are needed to confirm our results and determine whether reducing BPV can prevent or delay cognitive decline.

Gray matter volume mediates the association of long-term blood pressure variability with cognitive function in an adult population.

INTRODUCTION: We delineated the associations among long-term blood pressure variability (BPV), brain structure, and cognitive function. METHODS: We included 1254 adult participants from the Kailuan study. BPV was calculated from 2006 to 2020. Brain magnetic resonance imaging (MRI) and Montreal Cognitive Assessment (MoCA) were conducted in 2020. RESULTS: Higher systolic BPV (SBPV) and diastolic BPV (DBPV) were associated with lower total and frontal gray matter (GM) volume, and higher SBPV was associated with lower temporal GM volume. Elevated DBPV was associated with lower volume of total brain and parietal GM, and higher white matter hyperintensity (WMH) volume. Higher SBPV and DBPV were associated with lower MoCA scores. Decreased total and regional GM volume and increased WMH volume were associated with lower MoCA scores. The association between SBPV and cognitive function was mediated by total, frontal, and temporal GM volume. DISCUSSION: GM volume may play key roles in the association between SBPV and cognitive function. HIGHLIGHTS: SBPV and DBPV were negatively associated with total and regional brain volume. SBPV and DBPV were negatively associated with cognitive function. Decreased brain volume was associated with cognitive decline. GM volume mediated the negative association between SBPV and cognitive function.

Distinct effects of blood pressure parameters on Alzheimer's and vascular markers in 1,952 Asian individuals without dementia.

BACKGROUND: Risk factors for cardiovascular disease, including elevated blood pressure, are known to increase risk of Alzheimer's disease. There has been increasing awareness of the relationship between long-term blood pressure (BP) patterns and their effects on the brain. We aimed to investigate the association of repeated BP measurements with Alzheimer's and vascular disease markers. METHODS: We recruited 1,952 participants without dementia between August 2015 and February 2022. During serial clinic visits, we assessed both systolic BP (SBP) and diastolic BP (DBP), and visit-to-visit BP variability (BPV) was quantified from repeated measurements. In order to investigate the relationship of mean SBP (or DBP) with Alzheimer's and vascular markers and cognition, we performed multiple linear and logistic regression analyses after controlling for potential confounders (Model 1). Next, we investigated the relationship of with variation of SBP (or DBP) with the aforementioned variables by adding it into Model 1 (Model 2). In addition, mediation analyses were conducted to determine mediation effects of Alzheimer's and vascular makers on the relationship between BP parameters and cognitive impairment. RESULTS: High Aß uptake was associated with greater mean SBP (ß = 1.049, 95% confidence interval 1.016-1.083). High vascular burden was positively associated with mean SBP (odds ratio = 1.293, 95% CI 1.015-1.647) and mean DBP (1.390, 1.098-1.757). High tau uptake was related to greater systolic BPV (0.094, 0.001-0.187) and diastolic BPV (0.096, 0.007-0.184). High Aß uptake partially mediated the relationship between mean SBP and the Mini-Mental State Examination (MMSE) scores. Hippocampal atrophy mediated the relationship between diastolic BPV and MMSE scores. CONCLUSIONS: Each BP parameter affects Alzheimer's and vascular disease markers differently, which in turn leads to cognitive impairment. Therefore, it is necessary to appropriately control specific BP parameters to prevent the development of dementia. Furthermore, a better understanding of pathways from specific BP parameters to cognitive impairments might enable us to select the managements targeting the specific BP parameters to prevent dementia effectively.

Relationship between visit-to-visit blood pressure variability and depressive mood in Korean primary care patients.

BACKGROUND: High blood pressure variability (BPV) increases the risk of cardiovascular disease and may be better prognostic factor than blood pressure. Depressive mood is a common symptom among patients visiting primary care. This study aimed to investigate the association between depressive mood and high BPV among Korean primary care patients. METHODS: The Family Cohort Study in Primary Care (FACTS), conducted from April 2009 to November 2017, utilized a prospective cohort of Korean primary care patients, with a median follow-up period of 7.25 years. Depressive mood was assessed as a score of 21 points or more on the Korean-type Center for Epidemiologic Studies Depression scale. BP was measured at the initial visit and first and second follow-up visit. Visit-to visit SBP variability was analyzed using four metrics: intra-individual standard deviation, coefficient of variation, variation independent of mean, and average real variability. Logistic regression analysis was used to estimate the association of high BPV with depressive mood and other variables. RESULTS: Among 371 participants, 43 (11.6%) had depressive mood based on depression scores. Older age (odds ratio [OR]: 1.04, 95% confidence interval [CI]: 1.01-1.07) were associated with high SBP variability regardless of taking antihypertensive medication. Among participants taking antihypertensive medication, those with depressive mood had twice the risk of high SBP variability compared with those who did not (OR: 2.95, 95% CI: 1.06-8.20). CONCLUSIONS: Depressive mood was associated with high visit-to-visit SBP variability in primary care patients taking antihypertensive medication, potentially indicating increased cardiovascular risk. Primary care physicians should therefore closely monitor BPV in patients with depressive symptoms and provide appropriate interventions.

Effect of lidocaine on intraoperative blood pressure variability in patients undergoing major vascular surgery.

BACKGROUND: Dynamic fluctuations of arterial blood pressure known as blood pressure variability (BPV) may have short and long-term undesirable consequences. During surgical procedures blood pressure is usually measured in equal intervals allowing to assess its intraoperative variability, which significance for peri and post-operative period is still under debate. Lidocaine has positive cardiovascular effects, which may go beyond its antiarrhythmic activity. The aim of the study was to verify whether the use of intravenous lidocaine may affect intraoperative BPV in patients undergoing major vascular procedures. METHODS: We performed a post-hoc analysis of the data collected during the previous randomized clinical trial by Gajniak et al. In the original study patients undergoing elective abdominal aorta and/or iliac arteries open surgery were randomized into two groups to receive intravenous infusion of 1% lidocaine or placebo at the same infusion rate based on ideal body weight, in concomitance with general anesthesia. We analyzed systolic (SBP), diastolic (DBP) and mean arterial blood (MAP) pressure recorded in 5-minute intervals (from the first measurement before induction of general anaesthesia until the last after emergence from anaesthesia). Blood pressure variability was then calculated for SBP and MAP, and expressed as: standard deviation (SD), coefficient of variation (CV), average real variability (ARV) and coefficient of hemodynamic stability (C10%), and compared between both groups. RESULTS: All calculated indexes were comparable between groups. In the lidocaine and placebo groups systolic blood pressure SD, CV, AVR and C10% were 20.17 vs. 19.28, 16.40 vs. 15.64, 14.74 vs. 14.08 and 0.45 vs. 0.45 respectively. No differences were observed regarding type of surgery, operating and anaesthetic time, administration of vasoactive agents and intravenous fluids, including blood products. CONCLUSION: In high-risk vascular surgery performed under general anesthesia, lidocaine infusion had no effect on arterial blood pressure variability. TRIAL REGISTRATION: ClinicalTrials.gov; NCT04691726 post-hoc analysis; date of registration 31/12/2020.

Exploring the optimal lower blood pressure boundary during endovascular thrombectomy in patients with large vessel occlusion.

BACKGROUND: Current guidelines advocate for maintaining BP level below 180/105 mmHg during EVT, determining the safe lower boundary remains primarily consensus-driven by experts. This study aims to delve into the correlation between various targets of lower boundary for systolic and diastolic BP (SBP and DBP) during EVT and 3-month functional outcomes. METHODS: A cohort study was conducted across two EVT-capable centers, enrolling patients with large artery occlusion undergoing EVT within 8 h of stroke onset. Mean BP values during EVT were meticulously recorded, and logistic regression models were utilized to evaluate the correlation between outcomes and diverse lower boundary targets for SBP and DBP. Additionally, logistic regression models investigated the relationship between periprocedural BP variability and subsequent outcomes. RESULTS: Among the 201 patients included, having a SBP higher than 130 or 140 mmHg showed an independent association with increased good functional outcomes at 3 months (adjusted odds ratio, aOR 2.80, 95% Cis, 1.26-6.39 for 140 mmHg; aOR 2.34, 95% Cis, 1.03-5.56 for 130 mmHg). Additionally, an SBP exceeding 130 mmHg was correlated with decreased 3-month mortality (aOR, 0.24, 95% CI 0.07-0.74). No significant relationship was observed between DBP and functional outcomes. Patients with higher periprocedural SBP coefficient variance exhibited a decreased rate of good functional outcomes at 3 months (aOR, 0.42, 95% CI, 0.18-0.96). CONCLUSIONS: A SBP range above 130-140 mmHg could potentially serve as a safe lower boundary during EVT, while minimizing BP fluctuations may correlate with improved post-EVT functional outcomes.

Association between long-term visit-to-visit blood pressure variability and depression among Chinese middle-aged and older adults.

BACKGROUND: Whether there is a longitudinal association between long-term blood pressure variability (BPV) and subsequent depression among Chinese adults remains inconclusive. METHODS: This study utilized data from a nationwide cohort of the China Health and Retirement Longitudinal Study, which included participants aged > 45 years without prevalent psychiatric or memory-related diseases. The intra-individual coefficient of variation (CV) and standard deviation (SD) across 3 visits from 2011 to 2015 were used to examine the long-term variability in systolic BP (SBP) and diastolic BP (DBP). The depressive symptoms were examined using the 10-item Center for Epidemiologic Studies Depression Scale (CES-D-10), and moderate-to-severe depression was defined as CES-D-10 ≥ 15. RESULTS: A total of 5,249 participants (mean age: 61.4 ± 8.1 years, 46.5% were men) were included in the current analysis. Individuals in the highest quartile of both BP CV and SD were independently correlated with a higher total CES-D-10 score compared to those in the lowest quartile after multivariable adjustment. 1,070 participants (20.4%) had moderate-to-severe depression during the 3-year follow-up period. Participants in the Q4 of SBP and DBP CV had 1.23-fold higher odds (95% CI: 1.01, 1.49) and 1.20-fold higher odds (95% CI: 1.01, 1.41) of moderate-to-severe depression compared to those in Q1. Subgroup analyses revealed that men with higher BP CVs had a greater risk of severe depressive symptoms (p for SBP CV-by-sex interaction = 0.050, p for SBP CV-by-sex interaction = 0.025). CONCLUSIONS: Depression was common among Chinese middle-aged and older adults and long-term visit-to-visit BPV was positively associated with depressive symptoms, highlighting the importance of implementing intensive prevention strategies for depression and enhancing blood pressure monitors in China.

Association between antihypertensive treatment, blood pressure variability, and stroke severity and outcomes in acute ischemic stroke.

OBJECTIVES: The management of blood pressure (BP) and the role of antihypertensive medications (AHT) in acute ischemic stroke (AIS) remain uncertain. This study aimed to investigate the impact of pre- and intra-stroke AHT use on systolic (SBP), diastolic (DBP), and blood pressure variability (BPV). MATERIALS AND METHODS: A post-hoc analysis was conducted on 228 AIS patients from the PREVISE study. All patients underwent 24-hour ambulatory blood pressure monitoring within 48 h of symptom onset. Clinical and laboratory data, as well as AHT details, were recorded. Mean BP parameters and BPV for SBP and DBP were computed. The study endpoint was 3-month mortality. RESULTS: The majority of stroke patients (84.2%) were already taking AHTs. Beta blockers and ACE inhibitors use before and after stroke were linked to higher DBP variability. Prior angiotensin receptor blockers (ARBs) and vasodilators use correlated with increased SBP variability and lower daytime SBP/DBP levels, respectively. The continuation, discontinuation, or change of AHTs after stroke onset did not significantly affect outcomes. Patients under AHTs during AIS exhibited reduced mortality, with those previously using calcium channel blockers experiencing less severe strokes, and those previously using ARBs showing better outcomes at three months. CONCLUSIONS: These findings advocate for personalized BP management in AIS, based on a patient's antihypertensive history. These insights could enhance treatment efficacy, guide research, and improve care for acute ischemic stroke patients.

Reliability of beat-to-beat blood pressure variability in older adults.

Blood pressure variability (BPV) is emerging as an important risk factor across numerous disease states, including cerebrovascular and neurodegenerative disease in older adults. However, there is no current consensus regarding specific use cases for the numerous available BPV metrics. There is also little published data supporting the ability to reliably measure BPV across metrics in older adults. BPV metrics were derived from continuous beat-to-beat blood pressure monitoring data. Two sequential 7-minute waveforms were analyzed. Absolute and relative reliability testing was performed. Differences between antihypertensive medication users and non-users on BPV metric reliability was also assessed. All sequence and dispersion based BPV metrics displayed good test-retest reliability. A measure of BP instability displayed only moderate reliability. Systolic and diastolic average real variability displayed the highest levels of reliability at ICC= .87 and .82 respectively. Additionally, systolic average real variability was the most reliable metric in both the antihypertensive use group, and the no antihypertensive use group. Beat-to-beat dispersion and sequence-based metrics of BPV can be reliably obtained from older adults using noninvasive continuous blood pressure monitoring. Average real variability may be the most reliable and specific beat-to-beat blood pressure variability metric due to its decreased susceptibility to outliers and low frequency blood pressure oscillations.

Short-term blood pressure variability and brain functional network connectivity in older adults.

Background: Blood pressure variability is increasingly linked with cerebrovascular disease and Alzheimer's disease, independent of mean blood pressure levels. Elevated blood pressure variability is also associated with attenuated cerebrovascular reactivity, which may have implications for functional hyperemia underpinning brain network connectivity. It remains unclear whether blood pressure variability is related to functional network connectivity. We examined relationships between beat-to-beat blood pressure variability and functional connectivity in brain networks vulnerable to aging and Alzheimer's disease. Methods: 53 community-dwelling older adults (mean [SD] age = 69.9 [7.5] years, 62.3% female) without history of dementia or clinical stroke underwent continuous blood pressure monitoring and resting state fMRI scan. Blood pressure variability was calculated as variability independent of mean. Functional connectivity was determined by resting state fMRI for several brain networks: default, salience, dorsal attention, fronto-parietal, and language. Multiple linear regression examined relationships between short-term blood pressure variability and functional network connectivity. Results: Elevated short-term blood pressure variability was associated with lower functional connectivity in the default network (systolic: standardized ß = -0.30 [95% CI -0.59, -0.01], p = .04). There were no significant associations between blood pressure variability and connectivity in other functional networks or between mean blood pressure and functional connectivity in any network. Discussion: Older adults with elevated short-term blood pressure variability exhibit lower resting state functional connectivity in the default network. Findings support the role of blood pressure variability in neurovascular dysfunction and Alzheimer's disease. Blood pressure variability may represent an understudied early vascular risk factor for neurovascular dysfunction relevant to Alzheimer's disease, with potential therapeutic implications.

24-Hour Blood Pressure Variability Via Ambulatory Monitoring and Risk for Probable Dementia in the SPRINT Trial.

BACKGROUND: Blood pressure variability is an emerging risk factor for dementia, independent and oftentimes beyond mean blood pressure levels. Recent evidence from interventional cohorts with rigorously controlled mean blood pressure levels suggest blood pressure variability over months to years remains a risk for dementia, but no prior studies have investigated relationships with blood pressure variability over shorter time periods. OBJECTIVES: To investigate the potential effect of ambulatory blood pressure variability on the rate of cognitive outcomes under intensive vs standard blood pressure lowering. DESIGN: Post hoc analysis of the randomized, controlled, open-label Systolic Blood Pressure Intervention Trial clinical trial. SETTING: Multisite Systolic Blood Pressure Intervention Trial. PARTICIPANTS: 793 participants at increased risk for cardiovascular disease and without history of dementia at study randomization. INTERVENTION: Standard (<140 mmHg systolic blood pressure target) vs intensive (<120 mmHg systolic blood pressure target) lowering of mean blood pressure. MEASUREMENTS: 24-hour ambulatory blood pressure monitoring 27 months after treatment randomization (standard vs intensive) and follow-up cognitive testing. Intraindividual blood pressure variability was calculated as the average real variability over 24-hour, daytime, and nighttime periods. Participants were categorized into 3 adjudicated clinical outcomes: no cognitive impairment, mild cognitive impairment, probable dementia. Cox proportional hazards models examined the potential effect of ambulatory blood pressure variability on the rate of cognitive outcomes under intensive vs standard blood pressure lowering. Associations with mean blood pressure were also explored. RESULTS: Higher systolic 24-hour blood pressure variability was associated with increased risk for probable dementia in the standard group (adjusted hazard ratio [HR]: 2.56 [95% CI 1.16, 5.62], p = 0.019) but not in the intensive group (HR: 0.54 [95% CI 0.24, 1.23], p = 0.141). Similar findings were observed with daytime systolic blood pressure variability but not nighttime blood pressure variability. Mean blood pressure was not associated with cognitive outcomes. CONCLUSIONS: Higher systolic 24-hour and daytime blood pressure variability via ambulatory monitoring is associated with risk for dementia under standard blood pressure treatment. Findings support prior evidence that blood pressure variability remains a risk for dementia despite strict control of mean blood pressure levels.

Study on blood pressure rhythm in hypertensive patients withdeficiency syndrome and a random forest model for predicting hypertension withdeficiency syndrome.

OBJECTIVE: To investigate blood pressure rhythm (BPR) in Yin deficiency syndrome of hypertension (YDSH) patients and develop a random forest model for predicting YDSH. METHODS: Our study was consistent with technical processes and specification for developing guidelines of Evidence-based Chinese medicine clinical practice (T/CACM 1032-2017). We enrolled 234 patients who had been diagnosed with primary hypertension without antihypertensive medications prior to the enrollment. All participants were divided into Yin deficiency group (YX, n = 74) and non-Yin deficiency group (NYX, n = 160). Participants were professionally grouped by three experienced chief Traditional Chinese Medicine (TCM) physicians according to four examinations (i.e., inspection, listening and smelling, inquiry and palpation). We collected data on 24 h ambulatory blood pressure monitoring (ABPM) and YDSH rating scale. We divided 24 h of a day into 12 two-hour periods [Chen-Shi (7:00-9:00), Si-Shi (9:00-11:00), Wu-Shi (11:00-13:00), Wei-Shi (13:00-15:00), Shen-Shi (15:00-17:00), You-Shi (17:00-19:00), Xu-Shi (19:00-21:00), Hai-Shi (21:00-23:00), Zi-Shi (23:00-1:00), Chou-Shi (1:00-3:00), Yin-Shi (3:00-5:00), Mao-Shi (5:00-7:00)] according to the theory of "midnight-midday ebb flow". We used random forest to build the diagnostic model of YDSH, with whether it was Yin deficiency syndrome as the outcome. RESULTS: Compared with NYX group, YX group had more female participants with older age, lower waist circumference, body mass index (BMI), diastolic blood pressure (DBP), and smoking and drinking rate (all P ＜ 0.05). The YDSH rating scores of YX group [28.5 (21.0-36.0)] were significantly higher than NYX group [13.0 (8.0-22.0)] (P < 0.001), and the typical symptoms of YX group included vexing heat in the chest, palms and soles, dizziness, dry eyes, string-like and fine pulse, soreness and weakness of lumbus and knees, palpitations, reddened cheeks, and tinnitus (all P < 0.05). The ratio of non-dipper hypertension in YX group was higher than in NYX group (56.9% vs 44.4%, P = 0.004). Compared with NYX group, 24 h DBP standard deviation (SD), nighttime DBP SD, Si-Shi DBP, Si-Shi mean arterial pressure (MAP), Hi-Shi systolic blood pressure (SBP), Hi-Shi DBP, Hi-Shi MAP, Zi-Shi SBP, Zi-Shi DBP, Zi-Shi MAP, Chou-Shi SBP SD, Chou-Shi DBP SD, Chou-Shi SBP coefficient of variation (CV) were lower in YX group (all P ＜ 0.05). Binary Logistic Regression analysis showed that the diagnosis of YDSH was positively correlated with age, heart rate, YDSH rating scores, and four TCM symptoms including vexing heat in the chest, palms and soles, string-like and fine pulse, soreness and weakness of lumbus and knees, and reddened cheeks (all P ＜ 0.05), but was negatively correlated with smoking (P﹥0.05). In addition, the diagnosis of YDSH was positively correlated with daytime SBP SD, nighttime SBP SD, nighttime SBP CV, and Hi-Shi SBP CV, but was negatively correlated with 24 h SBP CV, daytime DBP SD, nighttime DBP SD, and Hi-Shi DBP (all P ＜ 0.05). Hi-Shi SBP CV had independent and positive correlation with the diagnosis of YDSH after adjusting the variables of age, gender, course of hypertension, BMI, waist circumference, SBP, DBP, heart rate, smoking and drinking (P = 0.029). Diagnostic model of YDSH was established and verified based on the random forest. The results showed that the calculation accuracy, specificity and sensitivity were 77.3%, 77.8% and 76.9%, respectively. CONCLUSION: The BPR was significantly attenuated in YDSH patients, including lower 24 h DBP SD and nighttime DBP SD, and Hi-Shi SBP CV is independently correlated with the diagnosis of YDSH. The prediction accuracy of diagnosis model of YDSH based on the random forest was good, which could be valuable for clinicians to differentiate YDSH and non-Yin deficiency patients for more effective hypertensive treatment of TCM.

Relationship between morning blood pressure variability and cerebral microbleed burden in patients with hypertension.

Cerebral microbleeds (CMBs) can be understood as a type of target organ damage caused by hypertension. We aimed to explore the association of the CMB burden with morning blood pressure (BP) variability in patients with hypertension. We divided patients with hypertension into two groups: a group with 1-10 CMBs and a group with more than 10 CMBs. The duration, grade, medication, and control of hypertension were recorded in all patients. Morning home BP measurements were performed every 3 days for a month. A total of 791 patients were recruited. Full factor model analysis showed that higher morning home diastolic BP variability (standard deviation [SD], OR = 1.080, 95% CI: 1.024-1.140, P = .005; coefficient of variation [CV], OR = 1.076, 95% CI: 1.028-1.128, P = .002) was associated with more than 10 CMBs. Morning home systolic and diastolic blood pressure variability (SD, CV, average real variability) in more than 10 non-lobar CMBs group was significantly higher than that in 1-10 non-lobar CMBs group (P < .05).The multivariate analysis showed higher morning home diastolic blood pressure variability (SD, OR = 1.124, 95% CI: 1.031-1.224, P = .008; CV, OR = 1.099, 95% CI: 1.019-1.186, P = .015; average real variability, OR = 1.055, 95% CI: 0.995-1.120, P = .075) was associated with more than 10 non-lobar CMBs. There was no significant relationship between morning home systolic blood pressure variability and more than 10 non-lobar CMBs (P > .05). Higher morning home diastolic blood pressure variability was associated with more than 10 CMBs and more than 10 non-lobar CMBs.