Indices Of Blood Pressure Variability Research Articles

#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.

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.

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 CV 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.

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.

Retracted: Diagnostic Value of Hcy Combined with Blood Pressure Variability Index in the Severity of Hypertension Complicated with CSVD and Its Correlation with Cognitive Function and CysC Expression.

[This retracts the article DOI: 10.1155/2022/9003537.].

Quantitative identification of daily mental fatigue levels based on multimodal parameters.

Fatigue has become an important health problem in modern life; excessive mental fatigue may induce various cardiovascular diseases. Most current mental fatigue recognition is based only on specific scenarios and tasks. To improve the accuracy of daily mental fatigue recognition, this paper proposes a multimodal fatigue grading method that combines three signals of electrocardiogram (ECG), photoplethysmography (PPG), and blood pressure (BP). We collected ECG, PPG, and BP from 22 subjects during three time periods: morning, afternoon, and evening. Based on these three signals, 56 characteristic parameters were extracted from multiple dimensions, which comprehensively covered the physiological information in different fatigue states. The extracted parameters were compared with the feature optimization ability of recursive feature elimination (RFE), maximal information coefficient, and joint mutual information, and the optimum feature matrix selected was input into random forest (RF) for a three-level classification. The results showed that the accuracy of classification of fatigue using only one physiological feature was 88.88%, 92.72% using a combination of two physiological features, and 94.87% using all three physiological features. This study indicates that the fusion of multiple physiological traits contains more comprehensive information and better identifies the level of mental fatigue, and the RFE-RF model performs best in fatigue identification. The BP variability index is useful for fatigue classification.

Determinants of short-term blood pressure variability – the value of arterial stiffness

Abstract. Increased blood pressure variability is a significant parameter that affects the prognosis in patients with arterial hypertension, and is an independent predictor of cardiovascular events and mortality. The arterial elasticity is an important factor in maintaining a constant average blood pressure for adequate blood supply to inner organs against the background of dynamic blood pressure fluctuations. A decrease in the elastic properties of the arteries, and therefore, an increase in the arterial stiffness can be one of the potential mechanisms for the blood pressure variability violation. Objective. The aim of the study was to evaluate the possible relationships between arterial stiffness indicators and blood pressure variability indices in patients with hypertension based on the results of ambulatory blood pressure monitoring. Patients and methods. The results of ambulatory blood pressure monitoring of 172 patients with hypertension were analyzed. Arterial stiffness was assessed using the ambulatory arterial stiffness index - symmetric and asymmetric. SD, SDw, CV, SV, ARV, and BPVR indices were calculated to assess blood pressure variability. Analysis of the obtained results was carried out using Microsoft Excel 2010 and the STATISTICA version 10.0 software. Differences between groups were assessed by the Mann-Whitney method, correlations among blood pressure variability indices and ambulatory arterial stiffness indices were evaluated using Spearman`s rank correlation analysis. Significance was set at p ˂ 0.05. The results. Awake asymmetric ambulatory arterial stiffness index was significantly higher than asleep one, no statistically significant difference between asleep and 24-hour asymmetric ambulatory arterial stiffness index was established. The asleep symmetric ambulatory arterial stiffness index did not significantly differ from the awake one and was significantly higher than the 24-hour one. In comparison with asymmetric, for symmetric ambulatory arterial stiffness index statistically significant relationships were established for a greater number of blood pressure variability indices. In all statistically significant cases, the direction of the established relationship with arterial stiffness was only direct for the systolic blood pressure variability indices. Variability of diastolic blood pressure had a clear inverse relationship with arterial stiffness. Conclusions. The presence of pathogenetic interrelationships between arterial stiffness and blood pressure variability have been proven in the present study. The obtained results allow to state that arterial elasticity is an important component of blood pressure variability.

DETERMINANTS OF WITHIN-VISIT OFFICE BLOOD PRESSURE VARIABILITY AND INSTABILITY: EUROPEAN DATA FROM 1.053 INDIVIDUALS

Objective: Blood pressure (BP) variability is the physiological sequelae of the complex interaction of multiple neural, humoral, reflex, and behavioral factors. This analysis aimed to evaluate the determinants of BP variability and instability within a single office visit, which is routinely used for hypertension evaluation in clinical practice. Design and method: A retrospective analysis of cross-sectional data was performed, comprising adults with triplicate office BP measurements in a single office visit and 24h ambulatory BP monitoring collected within the context of prospective clinical studies in Finland, Greece, and United Kingdom. Indices of BP variability and instability included: (i) standard deviation (SD) (ii) coefficient of variation (CV) (iii) average real variability (ARV) (iv) maximum office BP (Max) (v) maximum-minimum difference (MMD) of office BP (vi) ratio of the difference between 1st-3rd measurement to the mean office BP (Relative change). White-coat effect was defined as the difference between office and daytime ambulatory BP. Results: Data from 1.053 individuals were analyzed (mean age 57.7 ± 11.3 years, males 50%, treated hypertensives 50.3%, average office BP 133.5 ± 18.7/83.5 ± 10.9 mmHg, daytime ambulatory BP 132.5 ± 14.1/80.7 ± 9.9 mmHg). All the indices of BP variability and instability were positively associated with average office BP, age, BMI, and white-coat effect, but with an inverse association between age and maximum diastolic BP (all p &lt; 0.05). In multivariable linear regression analysis systolic BP variability was mainly determined by average office systolic BP, and treatment for hypertension, while diastolic BP variability was determined by office diastolic BP and female sex (Table). Conclusions: These results suggest that the variability and instability of BP within a single office visit is mainly influenced by the BP level, female sex and the administration of antihypertensive treatment.

NIGHT-TIME BLOOD PRESSURE AND BLOOD PRESSURE VARIABILITY IN HYPERTENSIVE PATIENTS WITH OR WITHOUT INSOMNIA. A PILOT STUDY

Objective: Recent studies found that insomnia is an independent risk factor for cardiovascular diseases, particularly arterial hypertension. Among the hypertensive population, insomnia could contribute to a worse blood pressure (BP) profile. In a sample of hypertensive patients, we compared those with and without insomnia with the aim of evaluating possible differences in BP, its variability, and breathing pattern. Design and method: We conducted a case-control study on patients with and without insomnia, based on the Insomnia Severity Index (ISI) questionnaire. Patients were recruited from the general practitioner's registry and were sent an invitation e-mail. All of them had long-lasting hypertension. One-hundred-and-fifty patients replied to the ISI questionnaire. Among them, twenty people with insomnia were selected (ISI greater than or equal to 15) and matched, based on their gender and age (±3 years), to 20 controls (with ISI lower than 15). All participants underwent night-time cardiorespiratory and 24-hour blood pressure monitoring by using a new cuff-less device that can estimate beat-to-beat BP (SomnoTouch-NIBP). Results: Comparing the two groups (insomnia vs. non-insomnia), no differences were observed in BP profile and all the respiratory indices, including the apnea-hypopnea index(AHI), the number of desaturations, and peripheral oxygen saturation (SpO2) values. Even the average BP and the indices of BP variability, such as the standard deviation (SD), the pressure coefficient of variation (CV), the BP dipping, and the nocturnal BP fluctuations (NBPF), were similar between the groups. Interestingly, to obtain the same average BP control, the insomnia group required a greater number of antihypertensive drugs (2,85 ± 0,88 vs. 1,95 ± 1,00 in the non-insomnia group; p&lt;0.01). Conclusions: Patients with insomnia may need more antihypertensive medications to achieve the same average BP as patients without insomnia. Anyhow, they did not show, as expected, higher BP variability. How much beat-to-beat BP estimations are reliable compared to BP measurements by standard cuff-based devices is still under debate.

PROGNOSTIC SIGNIFICANCE OF BLOOD PRESSURE FLUCTUATIONS IN THE MORNING AND EVENING FOR CARDIOVASCULAR OUTCOMES

Objective: Independent of office blood pressure (BP) levels, home BP is associated with the occurrence of cardiovascular events. Abnormal diurnal variations in BP have been linked to cardiovascular disease (CVD). However, data on diurnal patterns of home BP, the morning and evening BP difference (MEdiff), are scarce. This study looked into the relationship between all MEdiff indices and cardiovascular outcomes. Design and method: The association was assessed using data from the International Database of Home Blood Pressure in Relation to Cardiovascular Outcome (IDHOCO), which comprised 6753 patients from five cohorts. We found 1254 patients who had taken home BP readings every morning and every evening for more than 14 days. The MEdiff over a 13-day period, omitting the first day, for each patient were used to calculate the average (MEdiff_sbp_avg), minimum (MEdiff sbp_min), and maximum (MEdiff_sbp_max) values. MEdiff is defined as morning (6AM-8AM) minus evening BP (8PM-10PM) measures. The prognostic values of these parameters were assessed using Cox proportional hazards models. Factors adjusted in the base model included age, sex, body mass index, total cholesterol, high-density lipoprotein cholesterol, smoking status, prevalence of diabetes, history of cardiovascular disease, and antihypertensive drug treatment. Results: Only MEdiff_min_sbp strongly predicted CVD (183 events; mean follow-up time of 13.4 years), but MEdiff_avg_sbp (hazard ratio: 0.906, 95% CI: 0.087-1.018 per SD), MEdiff_max_sbp (0.949, 0.846-1.064 per SD) did not. Spline regression analysis with thresholds of -17 mmHg and -4 mmHg revealed a U-curve association between MEdiff_min_sbp and the risk of CVD outcomes. Three groups were identified by MEdiff_min_sbp: lower than -17 mmHg (Low, n = 574), between -17 and -4 mmHg (medium, n = 568) and higher than -4 mmHg (high, n = 112). Compared to the low group, the high group had a significantly higher risk of CVD (1.353, 1.052-1.739), in the models with adjustment for the mean of the morning and evening SBP values, and MEdiff_avg_sbp or various BP variability indices. Conclusions: MEdiff_min_sbp was strongly associated with an increased risk of cardiovascular outcomes, suggesting that it could be a useful BP index for describing abnormal BP diurnal variations for CVD risk prediction.

KIDNEY TRANSPLANTATION AND KIDNEY DONATION DO NOT AFFECT SHORT-TERM BLOOD PRESSURE VARIABILITY

Objective: Blood pressure variability (BPV) is an independent cardiovascular risk factor in CKD. Kidney transplantation (KTx) is associated with improved BP levels for kidney transplant recipient (KTRs), without evoking significant changes in donors. The aim of this study was to assess the short- and mid-time effects of KTx and donation on short-term BPV in KTRs and their respective living kidney donors. Design and method: Forty KTRs and their respective donors were evaluated with 24-h ABPM (Mobil-O-Graph-NG) at baseline (1 month before), 3-months and 12-months after KTx. Standard-deviation (SD), weighted-SD (wSD), coefficient-of-variation (CV), average-real-variability (ARV) and variability independent of mean (VIM) for SBP/DBP were calculated with validated formulas. Results: All 24-h systolic and diastolic BPV indexes studied did not change significantly from baseline to 3-month (SBP-wSD: 12.8±3.0 vs 13.2±3.4 mmHg, p = 0.608; SBP-ARV: 10.3±2.4 vs 10.8±2.6 mmHg, p = 0.463) and 12-month evaluation (SBP-wSD 12.8±3.0 vs 12.1±2.8; p = 0.424 and SBP-ARV: 10.3±2.4 vs 10.2±2.5; p = 0.615) after kidney transplantation in the KTRs. In kidney donors, all 24-h systolic BPV indices displayed a trend towards higher values at 3 months compared to baseline, but without reaching statistical significance (SBP-wSD: 12.2±2.8 vs 13.6±4.2 mmHg, p = 0.107 and SBP-ARV: 10.1±2.1 vs 11.2±3.1 mmHg, p = 0.099), the levels of 24-h systolic SBP indices at 12-months were almost identical to baseline values. 24-h diastolic BPV indices at 3-month and 12-month evaluation were similar to baseline. Conclusions: Short-term BPV did not change significantly 3 and 12 months after kidney transplantation/donation neither in KTRs nor in living kidney donors. Longitudinal studies examining associations of BPV with adverse outcomes in these individuals are needed.

SEX DIFFERENCES IN SHORT-TERM BP VARIABILITY AMONG PATIENTS UNDERGOING PERITONEAL DIALYSIS

Objective: The present study aimed to explore potential differences in short-term blood pressure (BP) variability between men and women with end-stage kidney disease undergoing peritoneal dialysis (PD). Design and method: In this comparative study, 48 male PD patients from Northern Greece were matched for age and history of heart failure with 48 female patients in a 1:1 ratio. All patients underwent 24-hour ambulatory BP monitoring with the oscillometric device Mobil-O-Graph (IEM, Stolberg, Germany). Short-term BP variability was assessed with the calculation of standard deviation (SD), coefficient of variation (CV) and average real variability (ARV) of systolic and diastolic BP during the 24-hour, daytime and nighttime periods. Results: Age, the duration of PD therapy and the prevalence of cardiovascular comorbidities were similar in men and women. During the 24-hour period, SD (13.4±3.8 vs. 14.6±3.1 mmHg, P = 0.091), CV (0.10±0.03% vs. 0.12±0.2%, P&lt;0.05) and ARV (10.7±3.1 vs. 11.9±2.6 mmHg, P&lt;0.05) of systolic BP were significantly lower in men than in women. Similarly, the variability of diastolic BP over the 24-hour period was numerically lower in men as compared with women (SD: 10.3±2.4 vs. 10.9±2.2 mmHg, P = 0.218; CV: 0.12±0.03% vs. 0.14±0.03%, P&lt;0.05; ARV: 8.4±2.0 vs. 9.0±1.9 mmHg, P = 0.136). These sex differences in indices of short-term BP variability were consistent during both daytime and nighttime periods. Conclusions: The present study shows that among patients undergoing PD, SD, CV and ARV of systolic and diastolic BP are lower in men than in women. Longitudinal studies are needed to explore whether these sex-related differences in short-term BP variability are prognostically informative in the PD population.

DETERMINANTS OF OFFICE BLOOD PRESSURE VARIABILITY AND INSTABILITY IN CHILDREN, ADOLESCENTS AND YOUNG ADULTS

Objective: To evaluate the determinants of office blood pressure (BP) variability and instability within a single visit in young individuals. Design and method: Apparently healthy individuals aged 6-25 years referred for elevated blood pressure (BP) were subjected to triplicate office BP measurements in a single visit and 24h ambulatory BP monitoring. BP variability and instability were assessed separately for systolic and diastolic BP using: (i) standard deviation (SD) (ii) coefficient of variation (CV) (iii) average real variability (ARV) (iv) maximum office BP (Max) (v) maximum-minimum office BP difference (MMD) (vi) ratio of difference between 1st-3rd measurement to the average office BP (Relative change). White-coat effect was defined as the difference between office and daytime ambulatory BP. Results: 320 individuals were analyzed (mean age 13.6±3.6 years, 66.8% males, BMI z-score 1.12±0.96, average office BP 122.6±16.6/72.6±10.7 mmHg, 24h ambulatory BP 119.3±11.5/67.8±6.8). Based on office and 24h ambulatory BP, 21.3% of the participants had white-coat hypertension, 8.1% masked and 16.6% sustained hypertension. Age was associated with SD (r = 0.23, p&lt;0.001), CV (r = 0.11, p&lt;0.05), Max (r = 0.54, p&lt;0.001) and MMD (r = 0.23, p&lt;0.001) of office systolic BP, and Max (r = 0.29, p&lt;0.001) and ARV (r = 0.12, p&lt;0.05) of diastolic. In multivariable log-linear regression models [(independent variables: age, sex, BMI z-score, heart rate, office BP, white-coat effect (&gt; = 5/6 mmHg systolic/diastolic, 75th centile)], office BP was an independent determinant for indices of systolic BP variability and instability [SD (↓ = 0.01, p&lt;0.001), ARV (↓ = 0.01, p&lt;0.001), Max (↓ = 0.01, p&lt;0.001), MMD (↓ = 0.01, p&lt;0.001) and Relative change (↓ = 0.001, p&lt;0.05)], and for CV (↓ = -0.06, p&lt;0.001) and Max (↓ = 0.01, p&lt;0.001) of diastolic. White-coat effect was a significant determinant for CV of office systolic BP (↓ = 0.15, p&lt;0.05) and Relative change of office diastolic BP (↓ = 0.03, p&lt;0.05). Conclusions: These results suggest that in healthy children, adolescents, and young adults the indices of office BP variability and instability within the first visit seem to be determined by the level of office BP and the magnitude of the white-coat effect.

Visit-to-Visit Blood Pressure Variability and Cardiovascular Outcomes in Patients Receiving Intensive Versus Standard Blood Pressure Control: Insights From the STEP Trial.

The clinical prognostic value of visit-to-visit blood pressure (BP) variability (BPV) is debatable, and relative studies among patients receiving BP control to achieve lower BP targets are limited. We analyzed a dataset from the STEP trail (Strategy of Blood Pressure Intervention in the Elderly Hypertensive Patients) to investigate the relationship between visit-to-visit BPV and cardiovascular events in patients with hypertensive aged 60 to 80 years. Visit-to-visit BPV was defined as the coefficient of variation, SD, delta, average real variability, and variability independent of the mean of BP measured at 6-, 9-, 12-, 15-, and 18-month follow-up visits. We computed hazard ratios for the risks associated with a 1-SD increase in BPV indexes in multivariable cox regression models. Among 7678 patients from the STEP trial, after adjustment for multiple confounders, diastolic BPV indexes were significantly associated with the primary composite end point (hazard ratios ≥1.21; P≤0.029) in the standard group, while there was no association between the clinical outcomes and systolic BPV (P≥0.091). In the intensive treatment group, either systolic or diastolic BPV was no association with clinical outcomes(P≥0.30). Sensitivity analyses using an alternative method to calculate BPV based on 7 BP records generated confirmatory results. In older adults with hypertension, visit-to-visit diastolic BPV is an independent predictor of adverse health outcomes in the standard treatment group. However, BPV did not have prognostic value in the intensive treatment group. URL: https://www. gov; Unique identifier: NCT03015311.

CKD patients have augmented beat-to-beat BP variability that is not improved with 12 weeks of cycling exercise

Increased blood pressure (BP) variability is a powerful predictor of cardiovascular events and end-organ damage and is associated with sympathetic overactivity. Given the heightened cardiovascular (CV) risk in patients with chronic kidney disease (CKD), we hypothesized that patients with CKD would exhibit augmented resting beat-to-beat BP variability. Additionally, since aerobic exercise training exerts CV protective effects and has been shown to reduce resting sympathetic activity, we hypothesized that twelve weeks of aerobic exercise training would improve resting beat-to-beat BP variability in patients with CKD. In 25 sedentary patients with CKD stages III-IV [19 male/6 female, age: 62 ± 10 yr, 23 Black/2 White, systolic/diastolic BP: 130 ± 12/73 ± 9 mmHg, BMI: 31 ±7 kg/m 2 ] and 15 controls [11 male/4 female, age: 56 ± 11 yr, 13 Black/2 White, systolic/diastolic BP: 129 ± 12/83 ± 8 mmHg, BMI: 29 ± 3 kg/m 2 ], resting beat-to-beat blood pressure (finger photoplethysmography) was continuously measured for 5–10 min. Next, a subset of patients with CKD (n = 13) underwent 12 weeks of aerobic cycling exercise (spinning at 85% of maximal heart rate reserve). Exercise training was performed 45 minutes/session 3 days/week. All measurements were performed at baseline (n=40) and following the 12-week intervention (n=13). We calculated the standard deviation (SD), the coefficient of variation [CV (SD/mean)×100], and the average real variability (AVR) as indices of BP variability. Compared with controls, patients with CKD had significantly increased BP variability. The systolic SD BP (6.0 ± 2.1 vs. 3.9 ± 1.8 mmHg, P = 0.002) and the mean SD BP (3.9 ± 1 vs. 2.8 ± 1 mmHg, P = 0.006) were increased in CKD vs. Controls, but there were no differences in diastolic SD BP between groups (3.3 ± 1 vs. 2.6 ± 1 mmHg, P = 0.065). Similar results were found using AVR (Systolic AVR 2.0 ± 0.5 vs. 1.1 ± 0.5 mmHg, P &gt; 0.001 and, Mean AVR, 1.3 ± 0.5 vs. 1.0 ± 0.3 mmHg, P = 0.010 for patients with CKD and controls respectively). Contrary to our hypothesis, we observed no significant change in resting beat-to-beat BP variability after 12 weeks of exercise in patients with CKD (SD SBP 6.3 ± 2.1 vs. 5.7 ± 2.0 mmHg, P = 0.893 and, AVR 1.9 ± 0.5 vs. 1.9 ± 0.6 mmHg, P = 0.970). In summary, our data demonstrate that patients with CKD have augmented beat-to-beat BP variability, and 12 weeks of cycling exercise did not reduce resting beat-to-beat BP variability in CKD patients. This work was supported by National Institutes of Health Grants R01HL135183 and R61AT010457 (J.P). This is the full abstract presented at the American Physiology Summit 2023 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.

Associations of all-cause mortality with admission blood pressure variability during multiple hospitalizations in acute decompensated heart failure

Objective: To investigate whether admission blood pressure (BP) variability during multiple hospitalizations is associated with all-cause mortality independent of baseline BP in acute decompensated heart failure (ADHF). Methods: Patients with ADHF admitted to the Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University from September 2013 to December 2017 were retrospectively enrolled. The risk of all-cause mortality associated with indices of BP variability, including mean admission BPs, standard deviation of BP and coefficient of variation of BP during multiple hospitalizations was assessed, using Cox regression model. Results: A total of 1 006 ADHF patients (mean aged (69.3±13.5) years; 411 (40.8%) female; 670 (66.6%) with preserved ejection fraction) were enrolled. During a median follow-up of 1.54 years, 47.0% of patients died. In all ADHF patients, after adjusting for confounding factors, for every 1-standard deviation (SD) increase in SD and coefficient of variation (CV) of systolic BP, the risk of all-cause mortality increased by 10% and 11%, respectively (SD: HR, 1.10, 95%CI, 1.01-1.21, P=0.029, CV: HR, 1.11, 95%CI, 1.02-1.21, P=0.017); for every 1-SD increase in the mean of diastolic BP, the risk of all cause mortality decreased by 25% (HR, 0.75; 95%CI, 0.65-0.87; P<0.001). In ADHF patients with preserved ejection fraction, after accounted for potential confounders, higher SD and CV of admitted systolic and diastolic BP were significantly associated with higher risk of all-cause mortality, regardless of whether confounding factors were adjusted (P≤0.049); After adjusting for confounding factors, the risk of all-cause mortality increased by 18% and 19% for every 1-SD increase in SD and CV of systolic BP, while the risk of all-cause mortality increased by 11% and 15% for every 1-SD increase in SD and CV of diastolic BP. In ADHF patients with reduced ejection fraction, after adjusting for confounding factors, the higher the mean admission systolic BP during multiple hospitalizations, the lower the risk of total mortality (HR, 0.68; 95%CI, 0.47-1.00; P=0.049). Conclusions: In patients with ADHF, independent of baseline BP, BP variability during multiple hospitalizations was strong predictor of all-cause mortality.

Prediction of blood pressure variability during thrombectomy using supervised machine learning and outcomes of patients with ischemic stroke from large vessel occlusion.

Mechanical thrombectomy (MT) is the standard of care for patients with acute ischemic stroke from large vessel occlusion (AIS-LVO). The association of blood pressure variability (BPV) during MT and outcomes are unknown. We leveraged a supervised machine learning algorithm to predict patient characteristics that are associated with BPV indices. We performed a retrospective review of our comprehensive stroke center's registry of all adult patients undergoing MT between 01/01/2016 and 12/31/2019. The primary outcome was poor functional independence, defined as 90-day modified Rankin Scale (mRS) ≥ 3. We used probit analysis and multivariate logistic regressions to evaluate the association of patients' clinical factors and outcomes. We applied a machine learning algorithm (random forest, RF) to determine predictive factors for the different BPV indices during MT. Evaluation was performed with root-mean-square error (RMSE) and normalized-RMSE (nRMSE) metrics. We analyzed 375 patients with mean age (± standard deviation [SD]) of 65 (15) years. There were 234 (62%) patients with mRS ≥ 3. Univariate probit analysis demonstrated that BPV during MT was associated with poor functional independence. Multivariable logistic regression showed that age, admission National Institutes of Health Stroke Scale (NIHSS), mechanical ventilation, and thrombolysis in cerebral infarction (TICI) score (OR 0.42, 95% CI 0.17-0.98, P = 0.044) were significantly associated with outcome. RF analysis identified that the interval from last-known-well time-to-groin puncture, age, and mechanical ventilation were among important factors significantly associated with BPV. BPV during MT was associated with functional outcome in univariate probit analysis but not in multivariable regression analysis, however, NIHSS and TICI score were. RF algorithm identified risk factors influencing patients' BPV during MT. While awaiting further studies' results, clinicians should still monitor and avoid high BPV during thrombectomy while triaging AIS-LVO candidates quickly to MT.

Kidney transplantation and kidney donation do not affect short-term blood pressure variability

PurposeBlood pressure variability (BPV) is an independent cardiovascular risk factor in CKD. Kidney transplantation (KTx) is associated with improved BP levels for kidney transplant recipient (KTRs), without evoking significant changes in donors. The aim of this study was to assess the short- and mid-time effects of KTx and donation on short-term BPV in KTRs and their respective living kidney donors.Materials and MethodsForty KTRs and their respective donors were evaluated with 24-h ABPM (Mobil-O-Graph-NG) at baseline (1 month before), 3-months and 12-months after KTx. Standard-deviation (SD), weighted-SD (wSD), coefficient-of-variation (CV), average-real-variability (ARV) and variability independent of mean (VIM) for SBP/DBP were calculated with validated formulasResultsAll 24-h systolic and diastolic BPV indexes studied did not change significantly from baseline to 3-month (SBP-wSD: 12.8 ± 3.0 vs 13.2 ± 3.4 mmHg, p = 0.608; SBP-ARV: 10.3 ± 2.4 vs 10.8 ± 2.6 mmHg, p = 0.463) and 12-month evaluation (SBP-wSD 12.8 ± 3.0 vs 12.1 ± 2.8; p = 0.424 and SBP-ARV: 10.3 ± 2.4 vs 10.2 ± 2.5; p = 0.615) after kidney transplantation in the KTRs.In kidney donors, all 24-h systolic BPV indices displayed a trend towards higher values at 3 months compared to baseline, but without reaching statistical significance (SBP-wSD: 12.2 ± 2.8 vs 13.6 ± 4.2 mmHg, p = 0.107 and SBP-ARV: 10.1 ± 2.1 vs 11.2 ± 3.1 mmHg, p = 0.099), the levels of 24-h systolic SBP indices at 12-months were almost identical to baseline values. 24-h diastolic BPV indices at 3-month and 12-month evaluation were similar to baseline.ConclusionShort-term BPV did not change significantly 3 and 12 months after kidney transplantation/donation neither in KTRs nor in living kidney donors. Longitudinal studies examining associations of BPV with adverse outcomes in these individuals are needed.