Indices Of Blood Pressure Variability Research Articles

Cardiovascular Precision Medicine and Remote Intervention Trial Rationale and Design

Background: It has recently been shown that excessive fluctuation in blood pressure readings for an individual over time is closely associated with poor outcomes, including increased risk of cardiovascular mortality, coronary heart disease and stroke. Fluctuations may be associated with inconsistent adherence to medical recommendations. This new marker of risk has not yet been incorporated into a monitoring and intervention strategy that seeks to reduce cardiovascular risk by identifying patients through an algorithm tied to their electronic health record (EHR). Methods: We describe the methods used in an innovative “proof of concept” trial using CP&R (Cardiovascular Precision Medicine and Remote Intervention). A blood pressure variability index is calculated for clinic patients via an EHR review. Consenting patients with excessive variability are offered a remote intervention aimed at improving adherence to medical recommendations. The outcomes include the ability to identify and engage the identified patients and the effects of the intervention on blood pressure variability using a pre–post comparison design without parallel controls. Conclusions: Our innovative approach uses a recently identified marker based on reviewing and manipulating EHR data tied to a remote intervention. This design reduces patient burden and supports equitable and targeted resource allocation, utilizing an objective criterion for behavioral risk. This study is registered under ClinicalTrials.gov Identifier: NCT05814562.

P217 MAY MEASUREMENT MONTH 2019: BLOOD PRESSURE VARIABILITY IN RELATION TO AGE AND SEX

Background and Objective: Within-visit blood pressure variability (BPV) is predictive of cardiovascular events independent of mean blood pressure (BP) levels and may serve as marker of cardiovascular aging. This study aimed to explore changes in BPV by age, and sex in May Measurement Month (MMM) 2019 survey participants. Methods: Adults (≥18 years) were surveyed opportunistically from 92 countries and up to three standardized seated BP readings were recorded. This analysis included all participants who were not taking BP-lowering medication and with complete data on age, sex, and three valid BP recordings. Three indices of BPV were compared: the standard deviation (SD), coefficient of variation (CV), and variation independent of the mean (VIM). A linear regression model was created for each index. Models were adjusted for mean BP, age, sex, and an interaction between age and sex. Age and mean BP were each included as natural cubic splines with 11 and 5 knots, respectively, to allow for flexibility with modelling relationships. Results: Data from 842,356 participants were included. The mean age was 42.9 (SD 15.9) years and 51.5% were female. Patterns of BPV from 18-90 years and by sex were consistent across BPV indices. Systolic BPV was higher in female than male participants between the ages of 30 and 80. In female participants, systolic BPV declined with age from 18-25, after which systolic BPV increased with age. In male participants, systolic BPV declined with age from 18-45, after which systolic BPV increased with age. Diastolic BPV was highest at the youngest and oldest ages, and lowest between 45 and 55 in both sexes. Conclusions: There was a highly consistent pattern amongst three commonly used indices of BPV in their relationships with age and sex. The BPV of screened adults was lower in males than females and varied non-linearly with age, with markedly higher BPV at younger and older ages, with distinct patterns of variation observed between systolic and diastolic BPV.

P087 ASSOCIATION OF INTRACRANIAL ARTERIAL STENOSIS WITH LEVEL AND VARIABILITY OF THE HOME BLOOD PRESSURE

Background and Objective: Given the close relation between intracranial arterial stenosis (ICAS) and systolic blood pressure (SBP), this study assessed whether blood pressure variability (BPV) refines risk stratification for ICAS over and beyond SBP using various BPV indexes derived from home blood pressure (BP) monitoring. Methods: In consecutively referred outpatients, all untreated for hypertension, ICAS was assessed by transcranial Doppler ultrasonography. SBP and BPV were determined from 7-day home BP recordings with triplicate readings in the morning and evening. BPV indexes included the standard deviation (SD), the coefficient of variation (CV), variability independent of the mean (VIM), and average real variability (ARV). ICAS probability was assessed with multivariable logistic models and model performance from the area under the curve (AUC). Results: Based on all home readings in 1510 patients, SBP, SD, CV, VIM, and ARV averaged 130.1 mm Hg, 8.36 mm Hg, 6.42%, 8.36, and 6.41 mm Hg. ICAS compared to non-ICAS patients had a similar CV and VIM (P≥0.09), but higher (P≤0.007) SBP, SD, and ARV by 3.9 mmHg, 0.66 mmHg, and 0.54 mmHg, respectively. ICAS was associated with SBP (P<0.001) irrespective of the time of day and with the BPV indexes independent of SBP in all morning readings (P≤0.050), but not in evening readings (P≥0.16). However, the AUC increment only reached significance for ARV in all readings and for CV, VIM, and ARV in morning readings. Conclusions: BPV derived from all-day and morning home BP readings was associated with ICAS independent of SBP but does not substantially refine ICAS risk assessment.

Abstract P381: Sex differences in association between gut microbiome and 24-hour blood pressure variability

Background: Blood pressure (BP) variability is an independent risk factor for cardiovascular disease (CVD). BP variability has been associated with cardiovascular organ damage and is a potential therapeutic target for the prevention of CVD. Recently, the gut microbiome (GM) has been shown to have a pathological role in hypertension, however, the association between GM and BP variability is poorly understood. Methods: 241 community-dwelling individuals free of symptomatic CVD from Hong Kong (113 males and 128 females, mean age 54±6 years) underwent ambulatory BP monitoring and stool microbiota shotgun sequencing. BP variability was determined as systolic/diastolic BP (SBP/DBP) coefficient of variation (CoV), nighttime dipping, and morning BP surge (MBPS). Sleep latency was estimated using 7-day Actigraphy data. Associations of BP variability with GM, and plasma and stool short-chain fatty acids (SCFAs) were analyzed under statistical models adjusting for age, sex, serum glucose and lipids, sodium intake assessed by urine analysis, menopause status, smoking, fatty liver, BP and sleep latency. Results: Women had a significantly higher 24-hour SBP ( p =0.0005) and DBP ( p =0.002) CoV than men. 24-hour SBP CoV had a negative association with GM α-diversity (Shannon and Simpson’s index: all P <0.05) and a positive association with Firmicutes/Bacteroidetes ratio ( P <0.05), suggesting gut dysbiosis in participants with higher systolic BP variability. Several GM species and SCFAs were significantly associated with the indices of BP variability in both men and women. Notably, Parabacteroides merdae had a negative association with both systolic and diastolic BP CoV (all P <0.05-0.01). Bacteroidetes dorei and Bacteroides intestinalis were reduced in women with higher SBP CoV ( P <0.05) and nondipping status ( P< 0.01), respectively. Prewaking and sleepthrough MBPS had a positive association with Faecalibacterium prausnitzii in women (all P <0.001) and plasma acetic acid levels in men ( P <0.05-0.001). Further analysis indicated that Bacteroidetes dorei may mediate SBP CoV via plasma iso-butyric acid in women (bootstrapping 95% CI: -3.6 to -0.19; P <0.05). Conclusions: This cross-sectional study suggests sex-specific associations between GM and BP variability. Most noteworthy, higher systolic BP variability was associated with a significant reduction in potentially beneficial bacterial species, primarily in women which may be explored for therapeutic potential.

Abstract 21: The Detrimental Effects of a Comorbidity of Increased Blood Pressure Variability and High Salt Diet on Cardiovascular and Neurovascular Outcomes

Recent studies have identified increased blood pressure variability (BPV) as a novel risk factor for cognitive decline, independently from absolute BP values. However, the underlying mechanisms are poorly defined. In addition, whether a high salt diet (HSD) contributes to BPV and exacerbates cognitive decline is not known. We tested the hypothesis that vascular damage resulting from blood pressure fluctuations in BPV disrupts critical mechanisms regulating cerebral blood flow (CBF), impairing perfusion and leading to neurovascular dysfunction and cognitive decline. We established a murine BPV model and evaluated the impact of BPV on systemic BP (baroreceptor reflex) and CBF regulation (myogenic and functional hyperemia (FH) responses). Mice were implanted with a cranial window for in-vivo two-photon (2P) imaging. A programmable pump infused 6-8 pulses/day of angiotensin II ((Ang II 18 µg/day) (BPV) or saline (Control) for 25 days, and cardiovascular variables were measured via DSI telemetry. Ang II pulse infusions evoked transient BP increases (Δ43±4 mmHg, MAP; P<0.01,n=8); however, did not induce hypertension in the BPV group. BPV mice displayed increased BPV index (P=0.04,n=12) and cognitive decline (novel object recognition test (P=0.01,n=10)). Telemetry data showed a decrease in bradycardic responses following chronic BPV (P=0.03, n=8). Data from 2P studies showed enhanced myogenic response in parenchymal arterioles of BPV vs Controls (P<0.01,n=9-15 runs) when BP transitions from low to high BP. We observed a blunted FH in BPV vs Control during low BP (P<0.01,n=6-7). During high BP, FH was pronounced in Controls (P<0.01,n=6-7); however, pressure-induced vascular responses were abolished in BPV mice (P<0.01,n=6-7). In separate groups of mice, the Control and BPV protocol was repeated with all mice receiving a high-salt diet (HS; 4% NaCl chow+1% NaCl drinking water: Control+HS or BPV+HS). There were no changes in 24-hr MAP in Control+HS (P>0.85, n=5). Whereas BPV+HS mice developed sustained hypertension (increased 24-hr MAP; P<0.01, n=4). These data demonstrate that BPV alters mechanisms regulating CBF and BP, contributing to cognitive decline and that HSD may exacerbate the detrimental effects of BPV on BP regulating mechanisms. Ongoing studies are examining the comorbid effects of BPV+HS on the cerebrovasculature and direct CBF changes in BPV and BPV+HS mice.

Abstract P106: Association of long term blood pressure variability and Major Cardiovascular events in patients with primary aldosteronism

Objective: Long-term blood pressure variability (BPV) is associated with an increased risk of major cardiovascular events (MACE), but it is rarely reported in patients with primary aldosteronism (PA). We aim to investigate the association between long-term BPV and cardiovascular events in patients with PA. Methods: This was a retrospective cohort study which conducted at the Hypertension Center of People’s Hospital of Xinjiang Uygur Autonomous Region from January 2006 to December 2021. The study included patients with PA aged over 30 years. The primary outcome was the incidence of major cardiovascular events during the follow-up, which extended until June 2023. The BPV index encompassed four parameters: standard deviation (SD), coefficient of variation (CV), average real variability (ARV), and maximum and minimum blood pressure difference (MMD). Multivariate analysis using logistic regression was performed, adjusting for demographic variables such as age, sex, body mass index, as well as clinical characteristics including smoking and alcohol consumption. Results: A total of 2,380 patients with PA were ultimately enrolled in this study. Access to clinic blood pressure was ensured at least three times during follow-up visits, with a minimum follow-up interval of 1 month. During a median follow-up of3.6 years, there were 124 cases of MACE. The mean age of the participants was 49.36 years, with men accounting for 1,288 cases. The average blood pressure recorded was 135 mmHg. After adjusting for confounding factors such as age, sex, smoking, alcohol consumption, BMI and cardiovascular risk factors, the systolic BPV (SD, CV, ARV) was found to be significantly associated with MACE (OR= 1.03, CI 1.02-1.05; P<0.05). In the group of mean SBP≥130mmHg, SBP variability had a significant association with MACE (OR: 1.03; CI: 1.01-1.06; P<0.05). However, no significant correlation between SBP variability and MACE in group of mean SBP <130mmHg (P>0 .05). Conclusion: Focusing on long-term systolic BP SD, CV, and ARV in patients with primary aldosteronism may help to prevent the occurrence of cardiovascular events.

Dialysate sodium and short-term blood pressure variability in patients with intradialytic hypertension: a randomized crossover study.

Increased blood pressure (BP) variability (BPV) is associated with high cardiovascular risk in hemodialysis. Patients with intradialytic hypertension (IDH) also exhibit an increased cardiovascular risk compared to hemodialysis patients without this condition. The impact of non-pharmacological BP-lowering interventions on BPV in this population remains unknown. This analysis evaluated the effect of low (137mEq/L) compared to standard (140mEq/L) dialysate sodium concentration on short-term BPV in patients with IDH. In a randomized cross-over manner, 29 IDH patients underwent 4 hemodialysis sessions with low (137mEq/L) followed by 4 sessions with standard (140mEq/L) dialysate sodium or vice versa. 48h ambulatory BP measurement was performed from the start of the 4th session on each dialysate sodium. BPV indices during the 48 h, 24 h, day-time and night-time periods were calculated. Mean 48h BP was 5.3/2.6 mmHg lower with low compared to standard dialysate sodium concentration, (p = 0.005/p = 0.007 respectively). All 48 h systolic BPV indices examined showed non-significant differences between low and standard dialysate sodium (SBP-SD: 16.99 ± 5.39 vs. 16.98 ± 4.33 mmHg, p = 0.982; SBP-wSD: 15.93 ± 5.02 vs. 16.12 ± 4.16 mmHg, p = 0.769; SBP-ARV: 11.99 ± 3.67 vs. 11.45 ± 3.35 mmHg, p = 0.392; SBP-CV: 12.36 ± 3.65 vs. 11.92 ± 3.18%, p = 0.302, with low vs. standard dialysate sodium, respectively). Diastolic BPV indices were numerically, but not statistically, lower with low dialysate sodium. Overall, significant differences were observed in some comparisons with a trend for lower BPV during day-time 2 and higher BVP during night-time 2 with low dialysate sodium. In conclusion, low dialysate sodium concentration does not affect BPV levels in patients with IDH. Future research should explore alternative interventions to reduce BP and BPV in this high-risk population.

Does a single oral administration of amiloride affect spontaneous arterial baroreflex sensitivity and blood pressure variability in healthy young adults?

Preclinical models indicate that amiloride (AMD) reduces baroreflex sensitivity and perturbs homeostatic blood pressure (BP) regulation. However, it remains unclear whether these findings translate to humans. This study investigated whether oral administration of AMD reduces spontaneous cardiac and sympathetic baroreflex sensitivity and perturbs BP regulation in healthy young humans. Heart rate (HR; electrocardiography), beat-to-beat BP (photoplethysmography), and muscle sympathetic activity (MSNA, microneurography) were continuously measured in 10 young subjects (4 females) during rest across two randomized experimental visits: 1) after 3 h of oral administration of placebo (PLA, 10 mg of methylcellulose within a gelatin capsule) and 2) after 3 h of oral administration of AMD (10 mg). Visits were separated for at least 48 h. We calculated the standard deviation and other indices of BP variability. Spontaneous cardiac baroreflex was assessed via the sequence technique and cardiac autonomic modulation through time- and frequency-domain HR variability. The sensitivity (gain) of the sympathetic baroreflex was determined via weighted linear regression analysis between MSNA and diastolic BP. AMD did not affect HR, BP, and MSNA compared with PLA. Indexes of cardiac autonomic modulation (time- and frequency-domain HR variability) and BP variability were also unchanged after AMD ingestion. Likewise, AMD did not modify the gain of both spontaneous cardiac and sympathetic arterial baroreflex. A single oral dose of AMD does not affect spontaneous arterial baroreflex sensitivity and BP variability in healthy young adults.NEW & NOTEWORTHY Preclinical models indicate that amiloride (AMD), a nonselective antagonist of the acid-sensing ion channels (ASICs), impairs baroreflex sensitivity and perturbs blood pressure regulation. We translated these findings into humans, investigating the impact of acute oral ingestion of AMD on blood pressure variability and spontaneous cardiac and sympathetic baroreflex sensitivity in healthy young humans. In contrast to preclinical evidence, AMD does not impair spontaneous arterial baroreflex sensitivity and blood pressure variability in healthy young adults.

Blood pressure variability assessed by office, home, and ambulatory measurements before and during antihypertensive drug treatment: a sub-analysis of the REVERENT randomized trial.

Blood pressure (BP) variability (BPV) can be assessed using office (OBP), home (HBP), or ambulatory BP (ABP) measurements. This analysis investigated the association and agreement between OBP, HBP, and ABP measurements for BPV assessment at baseline and 10 weeks after initiating antihypertensive drug therapy. Untreated hypertensive patients with elevated BPV were randomized to receive an angiotensin-converting enzyme inhibitor (ramipril) or a calcium channel blocker (nifedipine GITS) in a 10-week, open-label, blinded-end point study. BPV was assessed using standard deviation (SD) and coefficient of variation (CV) (reading-to-reading analyses). Data from 146 participants from three research centers (Athens/Greece; Milan/Italy; Shanghai/China) were analyzed [mean age 53 ± 10 (SD) years, male individuals 60%, baseline systolic OBP, HBP, and 24 h ABP 144 ± 9, 138 ± 10, and 143 ± 10 mmHg, respectively]. Post-treatment minus pre-treatment systolic CV difference was: OBP: 0.3%, P = 0.28; HBP: -0.2%, P = 0.20; 24 h ABP: 1.1%, P < 0.001. Home and ambulatory (not office) BPV indices presented weak-to-moderate correlation, both before and during treatment (range of coefficients 0.04-0.33). The correlation coefficient between systolic HBP and awake ABP CV was 0.21 and 0.28 before and during treatment, respectively ( P < 0.05/< 0.001, respectively). Home and ambulatory (not office) BPV indices presented slight-to-fair agreement (range 64-73%) in detecting participants with high systolic BPV (top quartile of respective distributions) both before and during treatment (kappa range 0.04-0.27). These data showed a weak-to-moderate association between out-of-office (but not office) BPV indices both before and during BP-lowering treatment, with reasonable agreement in detecting individuals with high BPV. Out-of-office BP measurements provide more similar and consistent BPV information than office measurements.

Short-Term Variability of Both Brachial and Aortic Blood Pressure is Increased in Patients with Immune-mediated Chronic Inflammation.

Blood pressure (BP) variability (BPV) has emerged as an indicator of subclinical organ damage and an independent predictor of cardiovascular disease (CVD) morbidity and mortality in high-risk populations. We aimed to assess short-term variability of both brachial and aortic BP in psoriasis, a common immune-mediated inflammatory disorder characterized by increased CVD risk. Psoriasis patients and non-psoriasis individuals had their BP assessed throughout a 24h period (Mobil-O-Graph device). Brachial and aortic BPV during the 24h and the respective daytime and nighttime periods was calculated from relevant ambulatory BP profiles. In-house software was applied to automatically calculate average real variability (ARV) of brachial and aortic systolic (bSBP, aSBP) and diastolic BP (bDPB, aDBP), and the weighted standard deviation (wSD) of 24h bSBP/aSBP. 24h pulse wave velocity (PWV) and augmentation index (AIx) were used as widely applied markers of arterial stiffness. Psoriasis patients (n = 74) presented increased ARV of 24h and daytime bSBP/aSBP, and increased ARV of 24h and daytime bDBP/aDBP, compared to controls (n = 40). PWV and AIx correlated with ARV of 24h bSBP/aSBP, daytime bSBP/aSBP, while PWV further correlated with ARV of nighttime aSBP. The observed associations with PWV, yet not AIx, with indices of BPV remained significant after adjusting for CVD risk factors. This is the first study reporting increased 24h variability of both brachial and aortic BP in psoriasis. The association of short-term BPV with arterial stiffness implies a potential role of BPV in terms of CVD risk stratification in patients with chronic immune-mediated inflammation.

Blood Pressure Variability and Plasma Biomarkers of Neuronal Injury and Alzheimer's Disease: A Clinic-Based Study of Patients with Diseases Along the Heart-Brain Axis.

Higher blood pressure variability (BPV) predisposes to cognitive decline. To investigate underlying mechanisms, we measured 24-h ambulatory BPV, nocturnal dipping and orthostatic hypotension in 518 participants with vascular cognitive impairment, carotid occlusive disease, heart failure, or reference participants. We determined cross-sectional associations between BPV indices and plasma biomarkers of neuronal injury (neurofilament light chain) and Alzheimer's disease (phosphorylated-tau-181 and Aβ42/Aβ40). None of the BPV indices were significantly associated with any of the biomarkers. Hence, in patients with diseases along the heart-brain axis, we found no evidence for an association between BPV and selected markers of neuronal injury or Alzheimer's disease.

#1488 Dialysate sodium and short-term blood pressure variability in patients with intradialytic hypertension: a randomized crossover study

Abstract Background and Aims Increased blood pressure (BP) variability (BPV) is associated with high cardiovascular risk in hemodialysis. Patients with intradialytic hypertension (IDH) also exhibited an increased cardiovascular risk than hemodialysis patients without this condition. The impact of non-pharmacological BP-lowering interventions on BPV in this population remains unknown. This analysis evaluated the effect of low (137 mEq/L) compared to standard (140 mEq/L) dialysate sodium concentration on short-term BPV in patients with IDH. Method In a randomized cross-over manner, 29 patients with IDH underwent 4 hemodialysis sessions with low (137 mEq/L) followed by 4 sessions with standard (140 mEq/L) dialysate sodium or vice versa according to randomization arm. 48-h ABPM was performed from the start of the 4th session on each dialysate sodium. BPV indices during the 48-h, 24-h, day-time and night-time periods were calculated with validated formulas. Results Mean 48-h BP was lower by 5.3/2.6 mmHg with low compared to standard dialysate sodium concentration, (p = 0.005/p = 0.007) respectively). All 48-h systolic BPV indices examined showed non-significant differences between low and standard dialysate sodium (SBP-SD: 16.99 ± 5.39 vs. 16.98 ± 4.33 mmHg; p = 0.982; SBP-wSD: 15.93 ± 5.02 vs. 16.12 ± 4.16 mmHg, p = 0.769; SBP-ARV: 11.99 ± 3.67 vs. 11.45 ± 3.35 mmHg, p = 0.392 and SBP-CV: 12.36 ± 3.65 vs. 11.92 ± 3.18%, p = 0.302, with low vs. standard dialysate sodium, respectively). Diastolic BPV indices were numerically, but not statistically, lower with low dialysate sodium. Overall, significant differences were observed in some further comparisons relevant to a trend for lower BPV during daytime 2 and higher BVP during nighttime 2 during treatment with low dialysate sodium. Conclusion Low dialysate sodium concentration does not affect BPV levels in patients with IDH. Future research should further explore alternative interventions to reduce BP and BPV in this high-risk population.

OBSTRUCTIVE SLEEP APNEA IN RELATION TO BEAT-TO-BEAT, READING-TO-READING, AND DAY-TO-DAY BLOOD PRESSURE VARIABILITY

Objective: We investigated blood pressure (BP) variability as assessed by beat-to-beat, reading-to-reading and day-to-day BP variability indices in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). Design and method: In 786 hospitalized hypertensives (mean age, 53.2 years; 42.2% women), we performed 10-minute beat-to-beat (n=705), 24-hour ambulatory (n=779), and 7-day home BP (n=445) measurements and the full overnight polysomnography. Mild, moderate and severe OSAHS were defined as an apnea-hypopnea index of 5-14, 15-29, and &gt;= 30 events per hour, respectively. BP variability indices including variability independent of the mean (VIM), average real variability (ARV), and maximum–minimum difference (MMD), were compared across the OSAHS severity groups. Results: In univariate analysis, beat-to-beat systolic VIM and MMD, reading-to-reading asleep systolic and diastolic ARV and MMD increased from patients without OSAHS, to patients with mild, moderate and severe OSAHS. This increasing trend for beat-to-beat systolic VIM and MMD remained statistically significant after adjustment for confounders (P &lt;=0.047). There was significant (P &lt;=0.039) interaction of the presence and severity of OSAHS with age and body mass index in relation to the beat-to-beat systolic VIM and MMD and with the presence of diabetes mellitus in relation to asleep systolic ARV. The association was stronger in younger (age &lt; 50 years) and obese (body mass index &gt;= 28 kg/m2) and diabetic patients. None of the day-to-day BP variability indices reached statistical significance (P&gt;=0.16). Conclusions: BP variability, in terms of beat-to-beat recordings, were higher with the more severe OSAHS, especially in younger and obese and diabetic patients.

Symptom Severity and Beat-to-Beat Blood Pressure Variability in Patients with Post-Traumatic Stress Disorder (PTSD)

Individuals with post-traumatic stress disorder (PTSD) have an elevated risk of developing cardiovascular disease. Emerging research suggests that blood pressure variability (BPV) may serve as an early indicator for increased cardiovascular disease risk. However, the relationship between post-traumatic stress symptom severity and symptom clusters, and comorbid conditions such as depression, with BPV is unclear. Purpose: The primary objective of this study was to investigate the relationship between the severity of PTSD and depression symptoms, PTSD symptom clusters, and beat-to-beat blood pressure variability (BPV) in a sample of individuals diagnosed with PTSD. We hypothesized that participants with greater PTSD symptom severity would have increased BPV. Methods: Twenty participants (mean age = 46 ± 10 yr; 70% males; 75% African American) with diagnosed PTSD were enrolled. PTSD severity and symptom clusters were assessed via the PTSD Checklist (PCL-5) and depression symptoms were assessed via Beck's Depression Inventory (BDI). Beat-to-beat blood pressure was recorded via finger photoplethysmography for a five-minute duration. BPV indices were calculated as the coeffcient of variation (CV), standard deviation (SD), and average real variability (ARV) for systolic, diastolic, and mean blood pressure. Pearson correlations were conducted to evaluate the association between symptoms and BPV outcomes. Participants were also categorized into two groups based on symptom severity. Independent t-tests were used to compare those with mild to moderate symptoms (n = 7) relative to participants with severe and extreme PTSD symptoms (n = 13). Results: PTSD symptom severity was significantly correlated with depression symptoms (r = 0.83, p &lt; 0.001). However, there were no significant correlations between BPV measures and either PTSD or depression symptoms. We did observe moderate non-significant correlations between the PTSD intrusive symptom cluster and diastolic and mean blood pressure CV (r = 0.33 and r = 0.29, p &gt; 0.05). Similar moderate correlations were observed between depression symptoms and diastolic and mean blood pressure CV (r = 0.31 and r = 0.29, p &gt; 0.05). No significant differences were observed between the two symptom severity groups in terms of systolic, diastolic, and mean blood pressure for CV, SD, and ARV (systolic CV 0.61 ± 0.17 vs. 0.62 ± 0.17 %, p &gt; 0.05, diastolic CV, 0.70 ± 0.06 vs. 0.72 ± 0.16 %, p &gt; 0.05, and mean blood pressure CV 0.63 ± 0.09 vs. 0.65 ± 0.15 %, p &gt; 0.05 for mild to moderate and severe to extreme PTSD symptoms, respectively). Conclusions: Contrary to our hypothesis, those with greater PTSD symptom severity did not have significantly greater BPV. In summary, our data demonstrate that higher PTSD symptoms are not associated with beat-to-beat BPV; however, the moderate correlations suggest that larger studies are needed to determine if PTSD intrusive symptoms and depression symptoms, are related beat-to-beat BPV indices. VA Merit I01-CX001065, and DOD PR210574. M. McGranahan is supported by NIDDK training grant TL1DK129502 and U2CDK129501. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

NON-LINEAR RELATIONSHIPS BETWEEN WITHIN-VISIT BLOOD PRESSURE VARIABILITY, MEAN BLOOD PRESSURE, SEX, AND AGE IN UNTREATED MAY MEASURMENT MONTH 2019 PARTICIPANTS

Objective: This study aimed to explore change in four commonly used measures of blood pressure variability (BPV) by mean blood pressure (BP), age, and sex in May Measurement Month (MMM) 2019 global survey participants. Design and method: We performed an observational analysis of BP readings from MMM 2019 participants. Adults (18 years and older) were surveyed via convenience sampling from 92 countries in May 2019. Each participant had three seated BP readings. Participants who reported taking antihypertensive medication or who lacked all three readings were excluded. Four indices of BPV were calculated: the standard deviation (SD), coefficient of variation (CV), absolute difference between the second and first BP readings (AR), and variation independent of the mean (VIM). A regression model was created for each index. Each model was adjusted for mean BP, age, sex, and an interaction between age and sex. Age and mean BP were each included as natural cubic splines with five knots. Results: Data from 922,259 participants were included. The mean age was 42.6 (SD 15.9) and 50.8% were female. Systolic SD and AR increased with higher mean BP up to 150 mmHg, while systolic CV and VIM decreased with higher BP across the BP range (Figure 1). Up to 90 mmHg, diastolic CV and VIM decreased with increased mean BP. All diastolic indices increased with higher mean BP above 90 mmHg. Systolic BPV was higher in females between 35 and 70 years (Figure 2), with little difference between sexes within diastolic BPV. Diastolic BPV was lowest between 40 and 50 years of age and highest in the youngest and oldest age groups. Systolic BPV was lowest between 25 and 30 years for females, and at around 45 years for males. Conclusions: All within-visit BPV indices examined showed non-linear variation with mean BP levels and age, particularly for diastolic BPV. Studies should consider non-linear effects when investigating and modelling BPV.

BLOOD PRESSURE VARIABILITY AND HISTORY OF CARDIOVASCULAR EVENTS IN MAY MEASUREMENT MONTH 2019 PARTICIPANTS

Objective: Increased blood pressure variability (BPV) is associated with negative health outcomes, but its determinants, and how best to measure it, remain unclear. We aimed to explore differences in four commonly used measures of BPV by clinical factors in the May Measurement Month (MMM) 2019 global survey. Design and method: We performed an observational analysis of BP readings from MMM 2019 survey participants. Volunteer adult (18 years or older) participants were surveyed via convenience sampling from 92 countries in May 2019. Each participant had three seated BP readings. Four indices of diastolic and systolic BPV were calculated for participants with all three BP readings: the standard deviation (SD), coefficient of variation (CV), absolute difference between the second and first BP readings (AR), and the variation independent of the mean (VIM). Factors examined included use of antihypertensive medication, being obese (body mass index greater than 29 kg/m2), and having a diagnosis of diabetes, myocardial infarction, or stroke. For each BPV index and factor, a regression model was created with the index as the outcome. Each model was adjusted for mean BP (based on the average of the second and third BP readings), age, sex, an interaction between age and sex, and antihypertensive medication use. Age and mean BP were each included as natural cubic splines with five knots. Results: Data from for 1,133,008 (75.1%) participants were included. The mean age was 45.6 (SD 16.6) and 52.0% were female. Coefficient estimates were similar for SD, VIM, and CV (Figure 1). Lower systolic and diastolic BPV were seen in participants who reported use of antihypertensive medication, and in those with a previous history of stroke, diabetes, or MI. There were small but statistically significant differences by obesity status. Conclusions: Diabetes, a history of myocardial infarction or stroke and the use of antihypertensive medication were associated with lower within-visit BPV, independent of age or sex. This may reflect underlying physiological differences between groups or differences in BPV-lowering effects resulting from different lifestyle choices or medication usage of these participants.

BLOOD PRESSURE VARIABILITY AS PREDICTOR OF CANCER THERAPY-RELATED CARDIOVASCULAR TOXICITY IN PATIENTS WITH MULTIPLE MYELOMA

Objective: Blood pressure variability (BPV) is an independent predictor of cardiovascular (CV) events and overall mortality. The potential role of BPV in defining CV risk of patients undergoing anticancer therapy with a potential cancer therapy-related cardiovascular toxicity (CTR-CVT) is currently unknown. The aims of this study were: (i) to assess the predictive value of BPV indexes for CTR-CVT development and defining the corresponding cut-off values; (ii) to identify subgroups of subjects based on BPV, through clustering analysis. Design and method: Patients with Multiple Myeloma, who were eligible to anticancer therapy with Carfilzomib, were consecutively enrolled and underwent a baseline evaluation, including office blood pressure (BP) measurement, 24h-Ambulatory Blood pressure Monitoring (ABPM), PWV, and Echocardiography. Short-term BPV was assessed through standard deviation (SD), weighted standard deviation (wSD), coefficient of variation (CoV), average real variability (ARV), and variability independent of the mean (VIM), evaluated on ABPM measurements. Results: The study population included 124 patients (50% female). During follow-up, CTR-CVT occurred in 70 subjects (56.5% of the total population), including both BP and CV events. Night-time BPV was associated to CTR-CVT, independently by BP, age, smoking, and comorbidities as diabetes and renal dysfunction (night-time systolic CoV: adjusted OR 1.11 [1.01-1.22]; night-time systolic VIM adjusted OR 1.17 [1.03-1.35]; night-time diastolic VIM adjusted OR 1.18 [1.01-1.40]). Cut-off for these BPV parameters were identified as predictor of CTR-CVT occurrence: 10.5 for night-time systolic CoV (sensibility 73%, specificity 47%); 7.8 and 6.4 for systolic and diastolic night-time VIM (sensibility 85% for both; specificity 35% and 39%, respectively). Clustering analysis identified a subgroup of subjects characterized by the highest BPV, who had a greater prevalence of events during follow-up, but no differences in other conventional CV risk factors, as BP, dyslipidaemia, diabetes, renal function, and smoking habit, as well as left ventricular mass and global longitudinal strain. Conclusions: Short-term BPV is an independent predictor of CTR-CVT in patients with Multiple Myeloma undergoing therapy with Carfilzomib. The inclusion of these indexes improves CV risk prediction in these subjects and higher BPV is a distinctive feature predicting adverse events, on top of conventional CV risk factors.

Obstructive sleep apnea in relation to beat-to-beat, reading-to-reading, and day-to-day blood pressure variability.

We investigated blood pressure (BP) variability as assessed by beat-to-beat, reading-to-reading and day-to-day BP variability indices in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). In 786 hospitalized hypertensives (mean age, 53.2 years; 42.2% women), we performed 10-min beat-to-beat (n = 705), 24-h ambulatory (n = 779), and 7-day home BP (n = 445) measurements and the full overnight polysomnography. Mild, moderate and severe OSAHS were defined as an apnea-hypopnea index of 5-14, 15-29, and ≥ 30 events per hour, respectively. BP variability indices including variability independent of the mean (VIM), average real variability (ARV), and maximum-minimum difference (MMD), were compared across the OSAHS severity groups. In univariate analysis, beat-to-beat systolic VIM and MMD, reading-to-reading asleep systolic and diastolic ARV and MMD increased from patients without OSAHS, to patients with mild, moderate and severe OSAHS. This increasing trend for beat-to-beat systolic VIM and MMD remained statistically significant after adjustment for confounders (P ≤ 0.047). There was significant (P ≤ 0.039) interaction of the presence and severity of OSAHS with age and body mass index in relation to the beat-to-beat systolic VIM and MMD and with the presence of diabetes mellitus in relation to asleep systolic ARV. The association was stronger in younger (age < 50 years) and obese (body mass index ≥ 28 kg/m²) and diabetic patients. None of the day-to-day BP variability indices reached statistical significance (P ≥ 0.16). BP variability, in terms of beat-to-beat systolic VIM and MMD and asleep reading-to-reading asleep systolic ARV, were higher with the more severe OSAHS, especially in younger and obese and diabetic patients.

Reduced resting beat-to-beat blood pressure variability in females with relapsing-remitting multiple sclerosis

BackgroundRelapsing-remitting multiple sclerosis (RRMS) is a demyelinating disease of the central nervous system and cardiovascular autonomic dysfunction has been well documented in this population. The sympathetic nervous system contributes to beat-to-beat blood pressure regulation primarily by baroreflex control of the peripheral vasculature which may be impaired in females with RRMS. Even at rest, attenuated sympathetic control of vasomotor tone may result in large and frequent blood pressure excursions (i.e., greater blood pressure variability). Therefore, the primary purpose of this investigation was to test the following hypotheses; (1) females with RRMS have augmented beat-to-beat blood pressure variability compared to healthy controls and (2) reduced sympathetic baroreflex sensitivity in females with RRMS is related to augmented blood pressure variability. MethodsElectrocardiogram and beat-to-beat blood pressure were continuously recorded during 8–10 min of supine rest in 26 females with clinically definite RRMS and 24 sex-, age- and BMI- matched healthy controls. Muscle sympathetic nerve activity (MSNA) was recorded in a subset of participants (MS, n = 15; CON, n = 14). Traditional statistical measurements of dispersions were used to index beat-to-beat blood pressure variability. Spontaneous sympathetic baroreflex sensitivity was quantified by sorting diastolic blood pressures into 3 mmHg bins and calculating MSNA burst incidence within each bin. Weighted linear regression was then used to account for the number of cardiac cycles in each bin and calculate slopes. Spontaneous cardiac baroreflex sensitivity was determined using the sequence method. ResultsGroups had similar resting mean arterial pressure (MAP), systolic blood pressure (SBP), diastolic blood pressure (DBP), MSNA burst frequency and MSNA burst incidence (All P > 0.05). The standard deviation and interquartile range of MAP, SBP and DBP were less in females with RRMS compared to healthy controls (All P < 0.05). There were no between groups differences in sympathetic baroreflex sensitivity or cardiac baroreflex sensitivity (Both P > 0.05) and baroreflex sensitivity measures were not related to any indices of blood pressure variability (Both P > 0.05). ConclusionThese data suggest that females with RRMS have reduced beat-to-beat blood pressure variability. However, this does not appear to be related to changes in sympathetic or cardiac baroreflex sensitivity.

Blood pressure variability and early neurological outcomes in acute and subacute stroke in Southwestern Uganda

BackgroundGreater blood pressure variability has detrimental effects on clinical outcome after a stroke; its effects are controversial and have not been evaluated in Sub-Saharan Africa (SSA). MethodsWe conducted a prospective study of patients with CT head confirmed ischemic and hemorrhagic strokes admitted to a tertiary hospital within 7 days of onset of unilateral neurological deficits. Blood pressure variability indices, standard deviation (SD) and coefficient of variation (CV) of systolic and diastolic blood pressure between day 0 and day 7, were calculated with a subsequent modified Rankin Scale (mRS) score on day 14 post-stroke. Linear regression was performed to determine the exponential coefficients of mortality at 14 days post- stroke. ResultsOut of 120 patients, 51.7% were female, 52.5% had ischemic stroke and the overall median age was 65 (IQR 54–80) years. Twenty (16.7%) patients died within a median survival time of 7 days, while 32 (26.7%) died by day 14 post-stroke. Patients with hemorrhagic stroke had an overall SDSBP of 16.44 mmHg while those with ischemic stroke had an overall SDSBP of 14.05 mmHg. In patients with ischemic stroke, SDSBP had adjusted coefficients of 1, p = 0.004 with C·I: 1.01–1.04 and NIHSS had adjusted coefficients of 1, p = 0.019 with C·I: 1.00–1.03 while in patients with hemorrhagic stroke, SDSBP had adjusted coefficients of 1, p = 0.045 with C·I: 1.00–1.04 and NIHSS had adjusted coefficients of 1, p ≤0.001 with C·I: 1.01–1.03. ConclusionExponential increase in Blood Pressure Variability (BPV) and stroke severity scale were independently associated with early mortality among all stroke patients in our study. We recommend future studies to evaluate whether controlling BPV among patients with stroke in Sub-Saharan Africa can reduce mortality.