Standard Deviation Of Systolic Blood Pressure Research Articles

Comparative Assessment of the Effects of Hydroxyethyl Starch and Normal Saline on Severe Hypotension in Patients with Aluminum Phosphide Poisoning: A Retrospective Study.

Background Aluminum phosphide poisoning is one of the most common forms of poisoning which requires immediate and urgent treatment. Objective This study aimed to compare the efficiency of two solutions, including hydroxyethyl starch and normal saline, in treating hypotension in patients with aluminum phosphide poisoning. Methods This retrospective cohort study was conducted on 35 patients with aluminum phosphide poisoning. We reviewed the profile of 18 patients treated with hydroxyethyl starch and 17 patients treated with normal saline. Within-group and between-group differences in systolic blood pressure before and after treatment were compared using paired t-test and independent t-test, respectively. Results The mean ± standard deviation (SD) age of the subjects in the starch and normal saline groups was 27.06 ± 9.72 and 27.88 ± 9.08, respectively. The levels of blood pressure in the two groups were not significantly different before the treatment; the mean ± SD of systolic blood pressure in the starch and normal saline groups was 72.67 ± 14.49 and 68.59 ± 8.3, respectively (P=0.313). After the treatment, it was significantly increased to 94 ± 24.45 and 85.18 ± 19.9 in the starch group (P=0.001) and the normal saline group (P=0.004), respectively. However, there was no significant difference between the two groups (P=0.245). Only one person survived in each group. Conclusion According to the results of this study, although there was no significant difference between the two groups in terms of their effects on hypotension, these treatments could not prevent mortality.

Prognostic significance of day-by-day in-hospital blood pressure variability in COVID-19 patients with hypertension.

Hypertension is the most common comorbidity in patients with coronavirus disease 2019 (COVID‐19) and increases in‐hospital mortality. Day‐by‐day blood pressure (BP) variability (BPV) is associated with clinical outcomes in hypertensive patients. However, little information is available on the association of BPV with the outcomes of COVID‐19 patients with hypertension. This study aimed to demonstrate whether day‐by‐day in‐hospital BPV had prognostic significance in these patients. The authors included 702 COVID‐19 patients with hypertension from Huoshenshan Hospital (Wuhan, China), who underwent valid in‐hospital BP measurements on at least seven consecutive days. Day‐by‐day BPV was assessed by standard deviation (SD), coefficient of variation (CV), and variation independent of mean (VIM). Overall, patients with severe COVID‐19 and non‐survivors had higher BPV than moderate cases and survivors, respectively. Additionally, higher BPV was correlated with greater age and higher levels of C‐reactive protein, procalcitonin, high‐sensitive cardiac troponin I, and B‐type natriuretic peptide. In multivariable Cox regression, SD of systolic BP (SBP) was predictive of mortality [hazard ratio (HR) 1.17, 95% confidence interval (CI) 1.05–1.30] as well as acute respiratory distress syndrome (ARDS) (HR 1.09, 95% CI 1.01–1.16). Similar trends were observed for CV and VIM of SBP, but not indices of diastolic BP variability. The authors demonstrated that day‐by‐day in‐hospital SBP variability can independently predict mortality and ARDS in COVID‐19 patients with hypertension. And high BPV might be correlated with severe inflammation and myocardial injury. Further studies are needed to clarify whether early reduction of BPV will improve the prognosis of these patients.

Abstract WP134: Association Between Hyperacute Blood Pressure Variability And Hematoma Expansion In Patients With Intracerebral Hemorrhage: Secondary Analysis Of The Field Administration Of Stroke Therapy - Magnesium Database

Background: Blood pressure variability (BPV) has emerged as a significant factor associated with clinical outcomes after intracerebral hemorrhage (ICH). While hematoma expansion (HE) is also associated with clinical outcomes, the relationship between BPV and HE has not been established. In this secondary database analysis, we aim to describe the association between BPV and HE. We hypothesized that BPV was positively associated with HE. Methods: Among 1,690 enrolled in the NIH-funded Field Administration of Stroke Therapy - Magnesium (FAST-MAG) study, 268 patients sustained ICH and received repeat CT or MRI head imaging within 6 to 48 hours of arrival. BPV was calculated by standard deviation (SD) and coefficient of variation (CV) of the hyperacute, prehospital data using the systolic blood pressure (SBP) measurements taken on ED arrival, 15min-post maintenance infusion start, 1-hour post maintenance infusion start, 4-hours after ED arrival. HE was defined by hematoma volume expansion greater than 6ml. Multivariate logistic regression was used for presence of HE in quintiles of SD and CV of SBP. Results: Of the 268 patients from the FAST-MAG study who had follow up head imaging, 116 (43%) had HE. Proportions of patients with HE was not statistically significant in the higher quintiles of the SD and CV of SBP for either hyperacute or acute period. Conclusions: HE was not found to be associated with higher quintiles of BPV using SD and CV of SBP in the hyperacute or the acute period. Expanded inclusion criteria or new statistical markers for BPV incorporating temporality for SBP could help in future studies.

Abstract TMP55: Post-stroke Blood Pressure Variability In The Acute Phase Is Associated With Pre-stroke Blood Pressure Variability In Patients Undergoing Mechanical Thrombectomy

Introduction: High blood pressure variability (BPV) after endovascular thrombectomy is associated with post-stroke complications and poor neurological outcomes. However, whether BPV is an epiphenomenon of the stroke itself or causally related to the outcome remains unknown. Objective: In this study we aimed to evaluate if a relationship exists between pre-and post-stroke BPV in patients with large vessel occlusions (LVO). Methods: From our prospective stroke registry, we identified patients who had an anterior circulation LVO, underwent EVT, and had at least three blood pressure measurements recorded in the electronic medical record in the six months prior to their stroke admission. All patients had repeated time-stamped blood pressure data recorded for the first 72 hours after thrombectomy. Using the standard deviation of systolic BP, we calculated BPV for each patient and separated patients into tertiles based on their post-EVT BPV. The relationship between pre-stroke BPV and post-EVT BPV was analyzed using an ordinal logistic regression and Spearman’s rank correlation analysis. Results: Two hundred fifty-two patients were included in our analysis (mean age 70±16.2 years, mean admission NIHSS 15±7, median pre-stroke BP measurements 14.5 (IQR 5.0-55.8)). Pre-stroke BPV gradually increased for patients with higher post-EVT BPV tertiles (tertile 1 = 13.2(±5.2) mmHg, tertile 2 = 15.0(±5.5) mmHg, tertile 3 = 16.7(±7.0) mmHg, p=0.001). A positive correlation was observed between pre-stroke BPV and post-EVT BPV (p<0.001, R=0.21). After adjusting for age and admission NIHSS, pre-stroke BPV was significantly associated with post-EVT BPV tertile membership (OR 1.37, 95% CI 1.02-1.86, p=0.039). Conclusion: High pre-stroke BPV is correlated with high post-EVT BPV. Although larger, prospective studies are needed to provide definitive evidence of this relationship, our work suggests that high post-EVT BPV may be related to an underlying biological phenomenon and not merely a consequence of the stroke itself. Individuals with high BPV may benefit from more intensive blood pressure management in the acute phase after EVT.

A Deep Learning-Based Continuous Blood Pressure Measurement by Dual Photoplethysmography Signals

This study proposed a measurement platform for continuous blood pressure estimation based on dual photoplethysmography (PPG) sensors and a deep learning (DL) that can be used for continuous and rapid measurement of blood pressure and analysis of cardiovascular-related indicators. The proposed platform measured the signal changes in PPG and converted them into physiological indicators, such as pulse transit time (PTT), pulse wave velocity (PWV), perfusion index (PI) and heart rate (HR); these indicators were then fed into the DL to calculate blood pressure. The hardware of the experiment comprised 2 PPG components (i.e., Raspberry Pi 3 Model B and analog-to-digital converter [MCP3008]), which were connected using a serial peripheral interface. The DL algorithm converted the stable dual PPG signals acquired from the strictly standardized experimental process into various physiological indicators as input parameters and finally obtained the systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP). To increase the robustness of the DL model, this study input data of 100 Asian participants into the training database, including those with and without cardiovascular disease, each with a proportion of approximately 50%. The experimental results revealed that the mean absolute error and standard deviation of SBP was 0.17 ± 0.46 mmHg. The mean absolute error and standard deviation of DBP was 0.27 ± 0.52 mmHg. The mean absolute error and standard deviation of MAP was 0.16 ± 0.40 mmHg.

AMBULATORY BLOOD PRESSURE VARIABILITY IN YOUNG ADULTS WITH LONG-COVID SYNDROME.

The aim: To perform an overall assessment of BP and BP variability using ambulatory measurements in young adults with long COVID syndrome. Materials and methods: We enrolled young patients with diagnosed long-COVID syndrome (n = 58, mean age 23.07 ± 1.54 years), compared with an age-matched healthy subjects who had not suffered from COVID-19 (n = 57, mean age 22.9 ± 1.83 years). Patients with long-COVID syndrome had recovered from mild/moderate illness and none had required hospitalization. Ambulatory 24 hours blood pressure (AMBP) parameters (mean BP, daytime BP, nighttime BP, pulse pressure, nocturnal systolic BP dipping, dipper status) were measured in all participants. The variability of systolic BP (SBP) and diastolic BP (DBP) values was assessed by the following common metrics, including the average real variability (ARV), the coefficient of variation (CV), the standard deviation (SD), and the weighed SD of SBP and DBP. Results: The average values of 24-hour ambulatory blood pressure, mean BP, daytime and nighttime systolic BP, diastolic BP and pulse pressure were found to be significantly different among patients with long COVID syndrome and control group. Group analyses showed that this difference was in SBP mean values (127.1 ± 6.65 mmHg and 115.93 ± 6.24 mmHg respectively) and DBP mean values (73.31 ± 5.30 mmHg and 68.79 ± 5.5 mmHg respectively) mainly at night. PP values at daytime were almost similar among groups, but PP values at nighttime were higher in patients with long-COVID syndrome (53.8 (52.44- 55.14) mmHg and 47.14 (46.45 - 47.88) mmHg respectively). Nocturnal SBP dipping was better in control group than in patients with long-COVID syndrome ( 5.3 ± 5.68 and 3.1 ± 3.79 mmHg respectively). Only 13 (22.4%) patients with long-COVID syndrome had normal dip-per status while more than half - 38 (66.7%) in healthy subjects. The values of ARV of SBP and DBP over 24-hour, awake, and asleep time frames were found to be greater in patients with long COVID syndrome than healthy controls (p < 0.05). Conclusions: Patients with long- COVID syndrome have higher BP mean values of 24-hour ABPM particularly at nightime, significant blood pressure BP variability, which increases the risk of cardiovascular events in future. Nevertheless, the further prospective investigations is warranted to investigate the potential mechanisms and causality associations.

Association of Circulating Osteoprotegerin Level with Blood Pressure Variability in Patients with Chronic Kidney Disease.

Circulating osteoprotegerin (OPG) is a biomarker for cardiovascular complications that are closely related to chronic kidney disease (CKD). To investigate the association between circulating OPG level with long-term visit-to-visit blood pressure variability (BPV) in patients with pre-dialysis CKD, a total of 1855 subjects with CKD from stage 1 to pre-dialysis stage 5 from a prospective cohort were analyzed. Long-term visit-to-visit BPV was determined by average real variability (ARV), standard deviation (SD), and coefficient of variation (CoV) of systolic and diastolic blood pressure (SBP and DBP). ARV of SBP (Adjusted β coefficient 0.143, 95% confidence interval 0.021 to 0.264) was significantly associated with serum OPG level. Although SD and CoV of SBP were not significantly associated with serum OPG level in multivariate linear regression analyses, restricted cubic spline visualized the linear correlation of serum OPG level with all of ARV, SD, and CoV. The association between serum OPG level and DBP variability was not significant. Subgroup analyses revealed that the association of serum OPG with BPV is more prominent in the subjects with Charlson comorbidity index ≤3 and in the subjects without history of diabetes mellitus. In conclusion, circulating OPG level is potentially associated with long-term visit-to-visit BPV in patients with pre-dialysis CKD.

Within-Visit Blood Pressure Variability in an Unselected Adult Population

Abstract Background To investigate blood pressure variability among 3 successive blood pressure measurements in an unselected nationwide population in China. Methods A total of 77,549 participants were included from measurements in May 2017 in China. Blood pressure was measured 3 times consecutively with a half minute interval. Blood pressure variability was estimated with the standard deviation and coefficient of variation of the systolic and diastolic blood pressure. Results Not all participants showed a decreasing trend with increasing number of measurements. In fact, 14% of the participants showed at least 5 mm Hg increase in systolic blood pressure. The coefficient of variation of systolic and diastolic blood pressure in women was higher than in men [(4.2 ± 3.3)% vs. (4.1 ± 3.3)%, (4.7 ± 4.0)% vs. (4.6 ± 4.1)%; P &amp;lt; 0.05]. The differences were significant (P &amp;lt; 0.01) among different groups of age and blood pressure levels. Multiple linear regression analysis showed that the systolic blood pressure variability indexes were inversely associated with age but positively associated with the level of the first systolic blood pressure reading (P &amp;lt; 0.01). The systolic blood pressure standard deviation and coefficient of variation in females were higher than in males (P &amp;lt; 0.01). Conclusions Not all subjects demonstrate a decreasing trend with increasing number of blood pressure measurements. Within-visit blood pressure variability varies with age, gender, and blood pressure.

Blood Pressure After Endovascular Thrombectomy and Malignant Cerebral Edema in Large Vessel Occlusion Stroke.

Background: Elevated blood pressure (BP) can cause blood–brain barrier disruption and facilitates brain edema formation. We aimed to investigate the association of BP level after thrombectomy with the development of malignant cerebral edema (MCE) in patients treated with endovascular thrombectomy (EVT).Methods: Consecutive patients who underwent EVT for an anterior circulation ischemic stroke were enrolled from three comprehensive stroke centers. BP was measured hourly during the first 24 h after thrombectomy. MCE was defined as swelling causing a midline shift on the follow-up imaging within 5 days after EVT. Associations of various BP parameters, including mean BP, maximum BP (BPmax), and BP variability (BPV), with the development of MCE were analyzed.Results: Of the 498 patients (mean age 66.9 ± 11.7 years, male 58.2%), 97 (19.5%) patients developed MCE. Elevated mean systolic BP (SBP) (OR, 1.035; 95% CI, 1.006–1.065; P = 0.017) was associated with a higher likelihood of MCE. The best SBPmax threshold that predicted the development of MCE was 165 mmHg. Additionally, increases in BPV, as evaluated by SBP standard deviation (OR, 1.061; 95% CI, 1.003–1.123; P = 0.039), were associated with higher likelihood of MCE.Interpretation: Elevated mean SBP and BPV were associated with a higher likelihood of MCE. Having a SBPmax > 165 mm Hg was the best threshold to discriminate the development of MCE. These results suggest that continuous BP monitoring after EVT could be used as a non-invasive predictor for clinical deterioration due to MCE. Randomized clinical studies are warranted to address BP goal after thrombectomy.

Relationship between year-to-year blood pressure variability and target organ damage in the general population

Abstract Background/Introduction Visit-to-visit blood pressure variability (BPV) is a strong predictor of cardiovascular events as well as target organ damage (TOD) in hypertension. However, effects of year-to-year BPV on the development of TOD have not been investigated in the general population. Purpose The present study was designed to investigate a possible relationship between year-to-year BPV and TOD in the general population. Methods Consecutive 5542 subjects (male=3771, 58.6±10.7 yea-old) who visited our hospital for an annual physical check-up for 5 years in a row during 2008 and 2013 were enrolled. The average, standard deviation (SD), coefficient of variation (CV), and average real variability (ARV) of systolic blood pressure (SBP) were calculated using data during the period. Other baseline data were obtained in 2013; left ventricular hypertrophy (LVH; Sokolow-Lyon voltage &amp;gt;3.8 mV and/or Cornell product &amp;gt;2440 mm ms) and kidney impairment (estimated glomerular filtration rate; eGFR&amp;lt;60) were taken as TOD. Then, subjects without TOD at baseline (2013) (n=3801, male=2584, 57.4±10.4 yea-old) were followed up until 2019 (median = 5 years) and the impact of BPV on the development of TOD was investigated. Results The average, SD, CV and ARV of SBP were 123.8 mmHg, 8.04 mmHg, 6.50%, and 9.19 mmHg, respectively. At baseline, these parameters were higher in subjects with TOD than those without TOD (Table 1-A). During the follow-up of subjects without TOD at baseline, LVH and kidney impairment developed in 425 and 623 subjects (24.7 and 35.8 per 1000 person-year), respectively. In retrospective analysis, the average, SD, and ARV were higher in subjects with than without future TOD (Table 1-B). Although some indices of year-to-year BPV predicted future development of TOD in univariate Cox-hazard analysis, only the average of SBP predicted incident TOD after adjustment. Conclusions Year-to-year BPV is a marker of the incident TOD in the general population. However, these indices do not independently predict the onset of TOD and, thus, there may be unknown pathway that links TOD and BPV. Funding Acknowledgement Type of funding sources: None. Table 1. BP variability and TODTable 2. Cox-hazard analyses

Association of Blood Pressure, Its Treatment, and Treatment Efficacy With Volume of White Matter Hyperintensities in the Population-Based 1000BRAINS Study.

[Figure: see text].

Correlation Between Serum Total Bilirubin Levels and Blood Pressure Variability in Patients With Hypertension

Abstract Background To investigate the effect of serum total bilirubin levels on blood pressure and its variability in patients with hypertension. Methods This study was a retrospective observational study. A total of 189 subjects were recruited from September 2019 to March 2020. All hypertensive patients were scheduled for ambulatory blood pressure and a 24-hour dynamic electrocardiography. Standard deviations of 24-hour systolic and diastolic blood pressure were used as blood pressure variability indicators. A multiple linear regression was used to analyze the relationship between total bilirubin serum levels and blood pressure variability in hypertensive patients. Results All patients were divided into 3 groups according to tertile values of total bilirubin: low (≤12.2 µmol/l, n = 64), moderate (12.3–16.7 µmol/l, n = 64), and high (&amp;gt;16.8 µmol/l, n = 62) total bilirubin groups. Compared with low total bilirubin group, 24-hour mean systolic and diastolic blood pressure, 24-hour systolic blood pressure standard deviation, systolic blood pressure coefficient of variability, and 24-hour systolic blood pressure load were reduced in the moderate and high total bilirubin groups (all P &amp;lt; 0.05). Multiple linear regression analysis showed that female (B = −1.408, P = 0.013), age (B = 0.043, P = 0.035), diabetes (B = 2.624, P &amp;lt; 0.001), and moderate and high bilirubin grouping (B = −1.582, −3.079; both P &amp;lt; 0.05) were influencing factors of 24-hour systolic pressure standard deviation. Serum total bilirubin levels had no effect on the standard deviation of 24-hour diastolic blood pressure(P &amp;gt; 0.05). Conclusions In hypertensive patients, the total bilirubin serum level is an influencing factor for 24-hour systolic blood pressure variability.

Increased Blood Pressure Variability and the Risk of Probable Dementia or Mild Cognitive Impairment: A Post Hoc Analysis of the SPRINT MIND Trial.

BackgroundIncreased systolic blood pressure variability (BPV) is associated with stroke, cardiovascular disease, and dementia and mild cognitive impairment. However, prior studies assessing the relationship between BPV and dementia or mild cognitive impairment had infrequent measurement of blood pressure or suboptimal blood pressure control.Methods and ResultsWe performed a post hoc analysis of the SPRINT (Systolic Blood Pressure Intervention Trial) MIND (Memory and Cognition in Decreased Hypertension) trial. The primary outcome was probable dementia during follow‐up. We defined our exposure period, during which blood pressures were collected, as the first 600 days of the trial, and outcomes were ascertained during the subsequent follow‐up. BPV was measured as tertiles of systolic blood pressure standard deviation. We fit Cox proportional hazards models to our outcome. We included 8379 patients. The mean follow‐up was 3.2±1.4 years, during which 316 (3.8%) patients developed dementia. The mean number of blood pressure measurements was 7.8, and in the tertiles of BPV, the SD was 6.3±1.6, 10.3±1.1, and 16.3±3.6 mm Hg, respectively. The rate of dementia was 2.4%, 3.6%, and 5.4% by ascending tertile, respectively (P<0.001). In the Cox models, compared with the lowest tertile of BPV, the highest tertile of BPV increased the risk of dementia in both unadjusted (hazard ratio [HR], 2.36; 95% CI, 1.77–3.15) and adjusted (HR, 1.69; 95% CI, 1.25–2.28) models.ConclusionsIn a post hoc analysis of the SPRINT MIND trial, we found that higher BPV was associated with the development of probable dementia despite excellent blood pressure control. Additional research is needed to understand how to reduce BPV and if its reduction lowers the risk of cognitive impairment and dementia.

Effect of free androgen index on blood pressure variability and target organ damage in postmenopausal hypertensive women: findings from a cross-sectional study.

Objective:The present study investigated the effects of free androgen index (FAI) on ambulatory blood pressure (ABP) and target organ function in postmenopausal hypertensive women.Methods:A total of 285 postmenopausal hypertensive women (mean age 54.06 ± 3.61) were admitted to the Department of Hypertension of Lanzhou University Second Hospital between December 2018 and December 2020. According to the serum FAI level, the participants were divided into a low-FAI (<0.15) group, a medium-FAI (0.15-0.2) group, and a high-FAI (>0.2) group. The relationship of FAI with 24-hour ABP, left ventricular mass index (LVMI), and cardio-ankle vascular index (CAVI) was analyzed.Results:The LVMI, CAVI, 24-hour mean systolic blood pressure (SBP), 24-hour SBP coefficient of variation and 24-hour SBP standard deviation, 24-hour SBP average real variation (ARV), and 24-hour diastolic blood pressure (DBP) ARV in high-FAI group were significantly higher than those in low- and medium-FAI groups (P < 0.05). After adjusting for confounding factors, partial correlation analysis showed that FAI was positively correlated with LVMI (r = 0.728, P < 0.001), CAVI (left: r = 0.718, P < 0.001; right: r = 0.742, P < 0.001), 24-hour SBP ARV (r = 0.817, P < 0.001), and 24-hour DBP ARV (r = 0.747, P < 0.001). After adjusting for confounding factors, it was found that LVMI increased by 17.64 g/m2 for every 1 unit increase in FAI. CAVI also increased by 8.983 for every additional unit of FAI. In addition, the results also showed that LVMI and CAVI decreased respectively by 0.198 g/m2 and 0.009 for every 1 unit increase in sex hormone–binding globulin. Multivariable linear regression showed that FAI was an independent risk factor for 24-hour SBP ARV (OR: 20.416, 95% CI 8.143-32.688, P = 0.001) and 24-hour DBP ARV (OR: 16.539, 95% CI 0.472-32.607, P = 0.044). The results also showed that sex hormone–binding globulin was an independent factor of 24-hour SBP ARV (OR: −0.022, 95% CI −0.044 to 0.000, P = 0.048) and 24-hour DBP-ARV (OR: −0.018, 95% CI −0.029 to −0.008, P = 0.001).Conclusion:Higher serum FAI levels in postmenopausal hypertensive women indicate abnormal BP regulation and more serious target organ damage. FAI is closely related to 24-hour SBP ARV and 24-hour DBP ARV in postmenopausal hypertensive women.

Age-Specific Associations of Usual Blood Pressure Variability With Cardiovascular Disease and Mortality: 10-Year Diabetes Mellitus Cohort Study.

BackgroundThe detrimental effects of increased variability in systolic blood pressure (SBP) on cardiovascular disease (CVD) and mortality risk in patients with diabetes mellitus remains unclear. This study evaluated age‐specific association of usual SBP visit‐to‐visit variability with CVD and mortality in patients with type 2 diabetes mellitus.Methods and ResultsA retrospective cohort study investigated 155 982 patients with diabetes mellitus aged 45 to 84 years without CVD at baseline (2008–2010). Usual SBP variability was estimated using SBP SD obtained from a mixed‐effects model. Age‐specific associations (45–54, 55–64, 65–74, 75–84 years) between usual SBP variability, CVD, and mortality risk were assessed by Cox regression adjusted for patient characteristics. After a median follow‐up of 9.7 years, 49 816 events (including 34 039 CVD events and 29 211 mortalities) were identified. Elevated SBP variability was independently, positively, and log‐linearly associated with higher CVD and mortality risk among all age groups, with no evidence of any threshold effects. The excess CVD and mortality risk per 5 mm Hg increase in SBP variability within the 45 to 54 age group is >3 times higher than the 70 to 79 age group (hazard ratio, 1.66; 95% CI, 1.49–1.85 versus hazard ratio, 1.19; 95% CI, 1.15–1.23). The significant associations remained consistent among all subgroups. Patients with younger age had a higher association of SBP variability with event outcomes.ConclusionsThe findings suggest that SBP visit‐to‐visit variability was strongly associated with CVD and mortality with no evidence of a threshold effect in a population with diabetes mellitus. As well as controlling overall blood pressure levels, SBP visit‐to‐visit variability should be monitored and evaluated in routine practice, in particular for younger patients.

Impact of indoor temperature instability on diurnal and day-by-day variability of home blood pressure in winter: a nationwide Smart Wellness Housing survey in Japan

Home blood pressure (HBP) variability is an important factor for cardiovascular events. While several studies have examined the effects of individual attributes and lifestyle factors on reducing HBP variability, the effects of living environment remain unknown. We hypothesized that a stable home thermal environment contributes to reducing HBP variability. We conducted an epidemiological survey on HBP and indoor temperature in 3785 participants (2162 households) planning to have their houses retrofitted with insulation. HBP was measured twice in the morning and evening for 2 weeks in winter. Indoor temperature was recorded with each HBP observation. We calculated the morning-evening (ME) difference as an index of diurnal variability and the standard deviation (SD), coefficient of variation (CV), average real variability (ARV) and variability independent of the mean (VIM) as indices of day-by-day variability. The association between BP variability and temperature instability was analyzed using multiple linear regression models. The mean ME difference in indoor/outdoor temperature (a decrease in temperature overnight) was 3.2/1.5 °C, and the mean SD of indoor/outdoor temperature was 1.6/2.5 °C. Linear regression analyses showed that the ME difference in indoor temperature was closely correlated with the ME difference in systolic BP (0.85 mmHg/°C, p < 0.001). The SD of indoor temperature was also associated with the SD of systolic BP (0.61 mmHg/°C, p < 0.001). The CV, ARV, and VIM showed similar trends as the SD of BP. In contrast, outdoor temperature instability was not associated with either diurnal or day-by-day HBP variability. Therefore, residents should keep the indoor temperature stable to reduce BP variability.

Systolic blood pressure variability following endovascular thrombectomy and clinical outcome in acute ischemic stroke: A meta-analysis.

Blood pressure variability (BPV) has been linked with the outcome of acute ischemic stroke (AIS) after endovascular thrombectomy (EVT). However, the association of the stroke outcome with specific short-term BPV parameters is unclear. We did a systematic literature search for studies published from January 2010 to September 2020. Eligibility criteria included studies with (1) AIS patients treated with EVT with or without thrombolysis; and (2) analysis of the association between short-term systolic BPV parameter and clinical outcomes. Systolic BPV parameters included standard deviation (SD), coefficient of Variation (CoV), successive Variation (SV), and Variation independent of mean. A total of 11studies were meta-analyzed, comprising 3520 patients who underwent EVT. Lower odds of achieving good functional outcome at 3months; that is, modified Rankin Scale (mRS) score ≤2 was associated with SD (OR, 0.854; p=.02), CoV (OR, 0.572; p=.04), SV (OR 0.41; p=.00) of systolic blood pressure (SBP). Likewise, higher odds of one-point increase in mRS score was associated with SD (OR 1.42; p=.03), CoV (OR 1.464; p=.00) and SV (OR 2.605; p=.00) of SBP. However, high BPV was not associated with symptomatic intracranial hemorrhage and all-cause mortality at 90days. The association of BPV and early neurological deterioration was inconclusive. Based on the available studies, short-term systolic BPV is indicative of the clinical outcome of patients following EVT in AIS. Further research should focus on personalized blood pressure management strategies, rather than a one-size-fits-all approach.

Long-term variability of blood pressure and incidence of heart failure among individuals with Type 2 diabetes.

AimsData on the association of long‐term variability of blood pressure (BP) with incident heart failure (HF) in individuals with Type 2 diabetes are scarce. We evaluated this association in a large community‐based sample of adults with Type 2 diabetes.Methods and resultsA total of 4200 participants with Type 2 diabetes who had available BP measurements at four visits (baseline and 12, 24, and 36 months) in the Look AHEAD (Action for Health in Diabetes) study were included. Variability of systolic BP (SBP) and diastolic BP (DBP) across the four visits was assessed using four metrics. Participants free of HF during the first 36 months were followed for HF events. Cox regression was used to generate hazard ratios (HRs) and 95% confidence intervals (CIs) for HF. Of the 4200 participants, the average age was 59 years [standard deviation (SD): 6.8]; 58.5% were women. Over a median follow‐up of 6.7 years, 129 developed HF events. After adjusting for relevant confounders, the HR of incident HF for the highest vs. lowest quartile of SD of SBP was 1.77 (95% CI 1.01–3.09); the HR for the highest (vs. lowest) quartile of variability independent of the mean of SBP was 1.29 (95% CI 0.78–2.14). The adjusted HR for participants in the highest (compared with the lowest) quartile of SD of DBP was 1.61 (95% CI 1.01–2.59), and the adjusted HR for variability independent of the mean of DBP was 1.65 (95% CI 1.03–2.65).ConclusionsA greater variability in SBP and DBP is independently associated with greater risk of incident HF in individuals with Type 2 diabetes.

The Influence of Salt Loading on Glomerular Filtration Rate and Blood Pressure Variability in Healthy Young Adults

Purpose High dietary sodium (Na+) is associated with glomerular hyperfiltration in patients with hypertension. Glomerular hyperfiltration is predictive of future cardiovascular and kidney disease. High dietary Na+ is also associated with greater blood pressure variability (BPV), which is predictive of target organ damage. However, it is unclear if short-term Na+ loading influences glomerular filtration rate (GFR) and BPV in healthy young adults. Therefore, we tested the hypothesis that short-term high Na+ intake would induce glomerular hyperfiltration (GFR > 135 ml/min) and increase BPV in healthy young adults. Methods Twenty participants (12M/8F; age: 24±4 years; BMI: 23.1±0.6 kg/m2; BP: 112 ±10/64±9 mmHg; mean ± SD) participated in a double-blind, placebo-controlled, randomized, crossover study. For 10-days, we asked participants to consume a 2,300 mg/day Na+ diet and supplement with salt (3,900 mg/day of Na+) or placebo (dextrose) capsules. The conditions were separated by ≥ two weeks and we tested female participants during the placebo phase of oral contraception. Participants collected their urine for the final 24 hours of each supplementation period to assess Na+ excretion to verify diet adherence. We measured serum creatinine (Jaffe reaction) to assess estimated GFR via the CKD-EPI equation (along with sex, age and race), and serum/urine creatinine to measure creatinine clearance. We measured brachial (oscillometric) and beat-to-beat BP (photoplethysmography). We used the average real variability index and standard deviation (SD) to assess beat-to-beat systolic, diastolic and mean BPV. Our statistical analyses included paired t-tests, Wilcoxon, and Chi-squared tests. Results Compared to placebo, Na+ supplementation increased urinary Na+ excretion (placebo: 139.9±68.4 vs. Na+: 282±69.8 mmol/24 hours, p<0.001) without differences in mean arterial BP (placebo: 77±7 vs. Na+: 77±6 mmHg, p=0.64). Estimated GFR was not different between conditions (p=0.27). However, compared to placebo, creatinine clearance increased with Na+ supplementation when unadjusted (placebo: 111±33 vs. Na+: 145±24 ml/min, p<0.001) and adjusted (placebo: 106±31 vs. Na+: 137±24 ml/min/1.73m2, p<0.001) for body surface area. There was a trend for an increased prevalence of glomerular hyperfiltration in the Na+ condition compared to placebo when evaluating unadjusted (placebo: 6/20 [30%] vs. Na+: 12/20 [60%], p =0.057) but not adjusted creatinine clearance. There were no differences in measures of BPV except SD of systolic BP (placebo: 5.6±2.2 vs. Na+: 6.5±2.0 mmHg, p=0.035) was modestly increased with Na+ supplementation. Conclusion Our preliminary data suggests that compared to CKD-EPI, creatinine clearance is a more sensitive measure for detecting glomerular hyperfiltration with salt loading in healthy young adults. Moreover, salt loading doesn't increase BPV.

Reduced resting beat‐to‐beat blood pressure variability in multiple sclerosis

Multiple Sclerosis (MS) is an autoimmune disease associated with central nervous system demyelination known to impair healthy autonomic function. We have previously demonstrated individuals with MS exhibit lower resting muscle sympathetic nerve activity and impaired carotid baroreflex control of arterial blood pressure compared to controls. Recently, increased resting beat-to-beat blood pressure variability (BPV) has been shown to be a strong predictor of cardiovascular risk in other clinical populations. Taken together, the aim of the current investigation was to test the hypothesis that resting beat-to-beat BPV is increased in individuals with MS compared to matched healthy controls. In 7 patients with relapsing-remitting MS (5 females/2 males, EDSS <4) and 7 sex-, age-, and weight-matched healthy controls, beat-to-beat blood pressure (Finometer) was recorded during 10 minutes of quiet supine rest. Individuals with MS had similar resting mean blood pressure (BP) compared to healthy controls (P= 0.736), however the BP standard deviation (SD) and coefficient of variation (CV) was less in MS (BP SD; MS: 3.2 ± 0.2 vs. CON: 4.0 ± 0.2, P=0.022 and BP CV; MS: 3.8 ± 0.3 vs. CON: 4.7 ± 0.2, P=0.025). Similarly, mean resting systolic blood pressure (SBP) was not different between MS and healthy controls (P=0.207) but the SBP standard deviation and coefficient of variation was less in MS (SBP SD; MS: 4.7 ± 0.4 vs. CON: 6.6 ± 0.5, P=0.013 and SBP CV; MS: 4.3 ± 0.4 vs. CON: 5.8 ± 0.4, P=0.033). In contrast, there was no difference in the DBP standard deviation or coefficient of variation between the two groups (P= 0.321 and P=0.295; respectively). In summary, contrary to our original hypothesis, individuals with MS exhibited reduced resting beat-to-beat BPV compared to healthy controls. These preliminary findings may be related to altered autonomic function in this clinical population.