Systolic Blood Pressure Slope Research Articles

Can Peripheral Arterial Tonometry and Biomarkers Help Identify Women Who Will Have Progressively Worsening Hypertensive Disorders of Pregnancy?

This study aimed to (1) evaluate whether endothelial dysfunction, as measured by peripheral arterial tonometry (PAT) indices and biomarker (soluble fms-like tyrosine kinase-1 [sFLT], brain natriuretic peptide [BNP]) levels at 34 weeks gestation, can predict progression from nonsevere to severe hypertensive disorders of pregnancy (HDPs); and (2) develop a clinical risk model for prediction of progression from nonsevere to severe HDP. We prospectively enrolled patients with a singleton gestation carrying a nonsevere HDP diagnosis. Forty-five participants were enrolled for PAT evaluation and serum collection between 340/7 and 366/7 weeks. PAT indices (e.g., Augmentation Index normalized to a heart rate of 75 bpm [AI75]) and biomarker concentrations were assessed at enrollment. The primary outcome was progression from a nonsevere diagnosis in the late preterm period to a diagnosis of preeclampsia with severe features or superimposed preeclampsia. Statistical analyses included two-sample t-tests, Fisher's exact tests, and multivariate modeling. Thirteen subjects (30%) progressed to severe disease. No significant differences in mean PAT indices between the outcome groups were found. We found a significant difference in mean sFLT values between the two groups (p = 0.02, area under the curve [AUC] of 0.609), but not in mean BNP values. An endothelial dysfunction index (presence of fetal growth restriction, "high" AI75, and positive systolic blood pressure slope) discriminated between progression and nonprogression (p = 0.03, AUC of 0.707). sFLT level was a marker of progression from nonsevere to severe HDP. Further, a novel endothelial dysfunction index discriminated between progression and nonprogression to severe disease with good performance. · HDPs are important causes of morbidity and mortality.. · The sequelae of HDPs are not limited to pregnancy.. · Developing accurate tools to predict severe HDPs is of great clinical importance.. · Our index shows promising performance for predicting progression from nonsevere to severe HDPs..

Test-retest reliability of exercise blood pressure and the workload-indexed systolic blood pressure slope in healthy males and females.

The reliability of blood pressure (BP) measured during submaximal and maximal exercise, and confounding effects of biological sex, remain to be fully established but have implications for using exercise BP as a cardiovascular risk factor. We hypothesize that exercise BP test-retest reliability will not differ between sexes but will be higher during submaximal compared to maximal exercise. Eighty-four participants (22±5 years; 36 females) completed two maximal treadmill tests (modified Bruce protocol) separated by ≥2 days. Exercise BP was measured every 90-seconds using automated auscultation (Tango M2 monitor). Breath-by-breath oxygen uptake was analyzed. Test-retest reliability was assessed using two-way, mixed effects, consistency, single-rater intraclass correlation coefficient (ICC) analysis on the total group and separated by sex at submaximal and maximal exercise. Systolic BP during submaximal (ICC=0.65 [0.49-0.76], p<0.01) and maximal (ICC=0.66 [0.52-0.77], p<0.01) exercise both displayed substantial reliability between visits. In contrast, the SBP/MET slope showed poor submaximal (ICC=0.12 [-0.09-0.33], p=0.13) but substantial maximal (ICC=0.63 [0.48-0.75], p<0.01) exercise reliability. Females showed substantial reliability in submaximal systolic BP (ICC=0.73 [0.53-0.85], p<0.01), and peak systolic BP (ICC=0.74 [0.54-0.87], p<0.01) and SBP/MET slope (ICC=0.78 [0.60-0.88], p<0.01); the submaximal SBP/MET slope had fair reliability (ICC=0.28 [-0.06-0.56], p=0.05). Males showed moderate reliability in submaximal systolic BP (ICC=0.53 [0.26-0.72], p<0.01), and peak systolic BP (ICC=0.41 [0.15-0.62], p<0.01) and SBP/MET slope (ICC=0.48 [0.22-0.67], p<0.01); the submaximal SBP/MET slope had poor reliability (ICC=0.06 [-0.18-0.31], p=0.32). Systolic BP showed similar reliability during submaximal and maximal exercise, with females demonstrating higher reliability in exercise systolic BP compared to males.

Race- and Sex-Specific Factors Associated With Age-Related Slopes in Systolic Blood Pressure: Findings From the CARDIA Study.

Although blood pressure (BP) increases throughout young adulthood for most individuals, the age-related slope is not uniform. This study aimed to assess associations of demographic, clinical, behavioral, psychosocial, and neighborhood characteristics with age-related BP slope among 4 race-sex groups who participated in the Coronary Artery Risk Development in Young Adults study. Individuals (n=3554) aged 18 to 30 years were included in this analysis if they had normal BP at baseline and ≥2 BP measurements during the years 1985/1986 to 2015/2016. Associations of exposure variables with systolic BP slope were assessed using multivariate linear models. Over a mean follow-up of ~30 years, greater decade increases in systolic BP were estimated among Black than White participants (mean difference between Black females and White females: 3.0 mm Hg/decade; between Black males and White males: 4.7 mm Hg/decade). The exposure risk factors associated with greater increases in systolic BP throughout adulthood varied by race and sex. None of these factors were associated with increases in systolic BP in all race-sex groups. Parent history of high BP was associated with a steeper positive slope among Black females (effect size per decade: 1.1 [95% CI, 0.6-1.6]; P<0.01), Black males (0.6 [95% CI, 0.02-1.2]; P<0.05), and White females (0.6 [95% CI, 0.2-1.0]; P<0.01). Other risk factors were associated with greater age-related yearly increases in systolic BP among 1 or 2 of the 4 race-sex groups or were not statistically significant. Culturally tailored BP reduction approach should be considered in conjunction with primordial prevention, to moderate increases in BP throughout adulthood.

Abstract P349: Predictive Value of Long-Term Systolic Blood Pressure Variability for the Development of Type 2 Diabetes Mellitus

Background: Better identification of high-risk individuals of type 2 diabetes mellitus (T2DM) for focused delivery of preventive measures requires risk prediction models using novel predictors. We evaluated the predictive value of long-term variability of systolic blood pressure (SBPV), which was recently reported to be associated with T2DM incidence, if added to a model with conventional T2DM predictors in a Japanese cohort study. Methods: A cohort of 3017 Japanese individuals (2446 male, 571 female) ages 36-65 years were followed from 2007 to 2019. Root-mean-square error (RMSE) and slope of systolic blood pressure (SBP) change regressed on year were calculated per individual using SBP values obtained consecutively from 2003 to 2007 to represent SBPV. An initial Cox model included age, sex, smoking status, regular exercise, family history of diabetes, body mass index (BMI), baseline SBP, blood levels of triglycerides (TG), high-density lipoprotein cholesterol (HDLC) and fasting blood glucose (FBG), and backward elimination was used for variable selection. The c-statistics, net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were used to compare the performance of prediction models without (Model 1) and with SBPV (Model 2). Results: During 9.8-year (median) follow-up, 135 developed T2DM. We confirmed that RMSE was significantly associated with T2DM incidence independent of other variables used in a conventional model. Backwards elimination procedure selected BMI, TG, HDLC, FBG, SBP RMSE, and SBP slope for the final model (Table 1). Although the c-indices were not statistically different between Model 1 (0.77) and Model 2 (0.78) as well as the NRI (7.1%), the IDI was statistically significant (0.8%, p&lt;0.05). Conclusions: The present study revealed that long-term variability of SBP slightly improved the predictive value of T2DM if added to a conventional prediction model.

Life-course blood pressure trajectories and incident diabetes: A longitudinal cohort in a Chinese population.

Blood pressure levels are correlated with diabetes among middle-aged or older adults. However, longitudinal trajectories of blood pressure during young adulthood and their impact on diabetes have been insufficiently studied. The longitudinal cohort consisted of 4,625 adults who had blood pressure and body mass index (BMI) repeatedly measured five to nine times during 18-60 years of age. Distinct systolic blood pressure (SBP) trajectories were identified by a group-based trajectory model. Logistic regression analyses were used to investigate the association between trajectory patterns or quartiles of area under the curve values of SBP trajectories and incident diabetes, respectively. Four distinct trajectory groups were identified for SBP: normotensive-stable (n = 761, 16.5%), prehypertension-stable (n = 2,381, 51.5%), stage I hypertension-increasing (n = 1,231, 26.6%), and stage II hypertension-increasing (n = 251, 5.4%). Compared with subjects who remained at SBP <120 mmHg in the normotensive-stable group, individuals in the prehypertension-stable trajectory exhibited a normal SBP range (<140 mmHg), and they still had a significantly higher risk of diabetes (adjusted OR = 1.82, p = 0.029). Individuals had a greater risk of diabetes in the stage I hypertension-increasing group (adjusted OR = 2.31, p = 0.006) and the highest risk in the stage II hypertension-increasing group (adjusted OR = 3.91, p < 0.001) relative to the normotensive-stable group. Furthermore, compared with the first quartile, adjusted ORs (95% CIs) of the fourth quartile of SBP incremental and total AUC were 2.50 (1.61-3.97) and 1.82 (1.15-2.94), respectively. Long-term SBP trajectory is a significant predictor for incident diabetes, which is independent of baseline SBP and body weight, attaching importance to maintaining optimal blood pressure levels and controlling changing slopes of SBP for preventing diabetes.

Long-term variability and change trend of systolic blood pressure and risk of type 2 diabetes mellitus in middle-aged Japanese individuals: findings of the Aichi Workers' Cohort Study.

Studies have reported that short-term blood pressure (BP) variability (BPV) is associated with type 2 diabetes mellitus (T2DM) incidence, but the association with long-term BPV remains unclear. The present study investigated the associations of long-term BPV as well as the time trend of BP changes over time with the incidence of T2DM. This study followed a cohort of 3017 Japanese individuals (2446 male, 571 female) aged 36-65 years from 2007 through March 31, 2019. The root-mean-square error (RMSE) and the slope of systolic BP (SBP) change regressed on year were calculated individually using SBP values obtained from 2003 to baseline (2007). A multivariable Cox proportional hazard model was applied to estimate hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) for tertiles of SBP RMSE and continuous SBP slopes adjusted for age, sex, smoking status, regular exercise, sodium intake, family history of diabetes, sleep disorder, body mass index (BMI), SBP, andfasting blood glucose (FBG) at baseline, and BMI slope from 2003 to 2007. The highest RMSE tertile compared to the lowest was associated with a significantly higher incidence of T2DM after adjusting for covariates (HR: 1.79, 95% CI: 1.15, 2.78). The slope was also significantly associated with T2DM incidence until baseline SBP and FBGwere adjusted (HR: 1.03, 95% CI: 0.99, 1.07). In conclusion, long-term SBP variability was significantly associated with an increased incidence of T2DM independent of baseline age, sex, BMI, SBP, FBG, lifestyle factors and BMI slope from 2003 until baseline.

Sympathovagal Balance And Insulin-stimulated Blood Flow Relates To Blood Pressure Dipping In Metabolic Syndrome

Blunted dips in nocturnal systolic blood pressure (SBP) are independently related to cardiovascular disease (CVD). While alterations in blood flow and sympathovagal balance have been suggested to explain dysregulated nocturnal SBP, the role of blood flow and/or sympathovagal balance is unknown in patients with metabolic syndrome (MetS). PURPOSE: We hypothesized that insulin-stimulated blood flow and heart rate recovery (HRR) as well as exaggerated SBP exercise response relates to nocturnal SBP dipping. METHODS: Twenty-eight adults with MetS (ATP III criteria) (53.2 ± 6.5y; 35.8 ± 4.5 kg/m2) were categorized as “dippers” (≥10% change in SBP; 4 M/6F) or “non-dippers” (<10%; 5 M/13F). Twenty-four hour ambulatory blood pressure monitoring was recorded to assess SBP dipping. Participants were fed isocaloric mixed meals for the 24-hr blood pressure monitoring period. A graded, incremental exercise test (VO2peak) was conducted to assess SBP and HR slope response during exercise to estimate sympathetic activity. Rate pressure product (RPP) was also calculated. HRR (peak-post-exercise) at 1 and 2 min post exercise was then used to determine parasympathetic activity. Ultrasound was performed before and after a 2-hr euglycemic hyperinsulinemic clamp (40 mU/m2/min, 90 mg/dl) to assess blood flow. Metabolic panels (e.g. estimated glomerular filtration rate (eGFR), circulating sodium and potassium) were also tested. Three-day food logs were collected in a subgroup (n = 16) to estimate habitual diet. RESULTS: There were no statistical differences in ATP III criteria, age, or eGFR between dippers and non-dippers. Additionally, there were no differences between groups in blood or dietary sodium and potassium. Although HRR and SBP slope during exercise did not differ between dippers and non-dippers, HR slope trended (7.0 ± 1.2 vs. 8.2 ± 1.7, P = 0.09). Interestingly, SBP dipping negatively correlated with HRR 1 minute after exercise (r = -0.60, P = 0.004) as well as insulin stimulated blood flow (r = 0.73, P = 0.04). Also, RPP correlated with nocturnal SBP (r = 0.49, P = 0.02). CONCLUSIONS: HRR, insulin-stimulated blood flow and RPP appear to play a role in nocturnal blood pressure dipping. Together, this work suggests that sympathovagal balance is important for blood flow related CVD risk. Funding: NIH RO1-HL130296.

Quantitative autonomic function test in differentiation of multiple system atrophy from idiopathic Parkinson disease.

Differential diagnosis of idiopathic Parkinson disease (IPD) and multiple system atrophy-Parkinson type (MSA-P) is challenging since they share clinical features with parkinsonism and autonomic dysfunction. To distinguish MSA-P from IPD when the symptoms are relatively mild, we investigated the usefulness of the quantitative fractionalized autonomic indexes and evaluated the correlations of autonomic test indexes and functional status. Thirty-six patients with parkinsonism (22 with IPD and 14 with MSA-P) in Soonchunhyang University Bucheon Hospital from February 2014 to June 2015 were prospectively enrolled in the study. We compared fractionalized autonomic indexes and composite autonomic scoring scale between patients with IPD and MSA-P with Hoehn and Yahr (H&Y) score ≤3. Parasympathetic indexes included expiratory/inspiratory ratio during deep breathing, Valsalva ratio (VR), and regression slope of systolic blood pressure (BP) in early phase II (vagal baroreflex sensitivity) during Valsalva maneuver. Sympathetic adrenergic indexes were pressure recovery time (PRT) and adrenergic baroreflex sensitivity (BRSa) (BP decrement associated with phase 3 divided by the PRT), sympathetic index 1, sympathetic index 3, early phase II mean BP drop, and pulse pressure reduction rate. Additionally, we compared the unified multiple system atrophy rating scale (UMSARS) and H&Y scores and the autonomic indexes in all patients. PRT was significantly different between the IPD and MSA-P groups (P = 0.004) despite the similar BP drop during tilt. Cut-off value of PRT was 5.5 s (sensitivity, 71.4%; specificity, 72.7%). VR (r = -0.455, P = 0.009) and BRSa (r = -0.356, P = 0.036) demonstrated a significant correlation with UMSARS and H&Y scores. Among the cardiovascular autonomic indexes, PRT can be a useful parameter in differentiating the early stage of MSA-P from that of IPD. Moreover, VR, and BRSa may be the optimal indexes in determining functional symptom severity.

Late-life blood pressure association with cerebrovascular and Alzheimer disease pathology.

To examine associations of average and change in late-life blood pressure (BP) with cerebrovascular and Alzheimer disease (AD) neuropathology in a large group of decedents followed longitudinally in vivo. This clinical-pathologic study was derived from prospective, community-based cohort studies of aging with similar design and data collection. Measurements of systolic BP (SBP) and diastolic BP (DBP) were obtained annually (mean follow-up 8 years, SD = 4.8). Postmortem neuropathologic evaluations documented diseases of aging. Using regression analyses, we examined associations of average and decline in late-life SBP, and separately in DBP, with neuropathology. In 1,288 persons (mean age at death = 88.6 years; 65% women), the mean standardized person-specific SBP across the study was 134 (SD = 13) and DBP was 71 (SD = 8) mm Hg. The odds of brain infarcts were increased for participants with a higher mean SBP. Specifically, a person with a 1 SD SBP above the mean (147 vs 134 mm Hg) would have a 46% increased odds of having one or more infarcts, and an increased odds of gross infarct (46%) and microinfarct (36%). Furthermore, a more rapidly declining SBP slope over time increased the odds of one or more infarcts. Mean DBP, not slope, was related to brain infarcts. AD pathology analyses showed an association of a higher mean SBP with higher number of tangles (p = 0.038) but not plaques or other pathology (all p > 0.06). Changes in BP were not significantly related to AD pathology. Higher average late-life SBP and DBP, and independently a faster decline in SBP, are associated with increasing number of brain infarcts, including gross and microinfarcts. We found some evidence for a relation of SBP with AD, specifically tangles. Both average and decline in BP are related to brain disease.

Abstract P357: Trajectories of Stroke Risk Factors Before Stroke Onset With a 24-year Follow-up of Japanese People Living in an Urban Area: The Suita Study

Introduction: Many studies investigated associations of stroke risk factors assessed at one point in time with stroke onset. However, few studies investigated growth curves (trajectories) of the stroke risk factors assessed at multiple points in time before stroke onset. Hypothesis: We assessed the hypothesis that people with stroke, compared with their controls, would have higher values of the stroke risk factors at multiple points in time and higher change rates by year (slopes) of those factors before stroke onset. Methods: The present study used a nested case-control design based on the Suita study that is a cohort study launched in 1989 with 15,746 community-dwelling participants in an urban city, Suita, Japan. During a 24-year follow-up, 201 cases (43.8% in women) were identified. Corresponding to the cases, 2010 controls (51.5% in women) matched by age (± 4 years) were identified by incidence density sampling. As the stroke risk factors, we included systolic blood pressure (SBP), diastolic BP (DBP), blood glucose level, body mass index, waist circumference, non-HDL cholesterol, and triglyceride assessed every two years on health check-ups. Linear mixed models were performed to investigate adjusted mean differences in the stroke risk factors between the stroke cases and the controls at 20, 15, 10, 5 years and the last assessment before stroke onset. Mean differences in slopes of the stroke risk factors before stroke onset were also investigated. Results: The linear mixed models showed that SBP and DBP were significantly higher in the cases than the controls at any points in time before stroke onset (the adjusted mean differences [95% CI] at the last assessment before stroke onset: 4.52 [1.4, 7.64] mmHg for SBP and 2.93 [1.23, 4.63] mmHg for DBP). However, slopes of SBP and DBP were not significantly different between the cases and the controls. We observed no significant difference between the cases and the controls in blood glucose level at 20 years before stroke onset (the adjusted mean difference: 2.24 [-0.26, 4.74] mg/dl). However, compared with the controls, the cases significantly had a steeper slop of blood glucose increase (the adjusted mean difference in the slope per year: 0.21 [0.02, 0.40] mg/dl; and the adjusted mean differences at 15, 10, and 5 years and the last assessment before stroke onset: 3.29 [1.31, 5.26], 4.34 [2.51, 6.16], 5.39 [3.25, 7.52], 6.44 [3.69, 9.19] mg/dl, respectively). We observed no significant differences of means and slopes in BMI, waist circumference, non-HDL cholesterol, and triglyceride between the cases and the controls. Conclusions: In conclusions, multiple assessments of the stroke risk factors on health check-ups can be useful to early identify people who will be likely to develop stroke by observing SBP and DBP at any points in time, and the trajectory of blood glucose level.

Abstract P097: Trajectories of Childhood Blood Pressure and Adult Left Ventricular Hypertrophy: The Bogalusa Heart Study

Background: Childhood blood pressure (BP) levels predict adult left ventricular hypertrophy (LVH). However, information is limited on the association between childhood BP trajectory and adult LVH. This longitudinal study aims to characterize longitudinal BP trajectories from childhood and examine the impact of level-independent childhood BP trajectories on adult LVH and remodeling patterns. Methods: The longitudinal cohort consisted of 1,154 adults (787 whites and 367 blacks) who had repeated measurements of BP 4-15 times from childhood (4-19 years) to adulthood (20-51 years) and assessment of echocardiographic LV dimensions in adulthood. Model-estimated levels and linear slopes of BP at childhood age points were calculated in one-year intervals using the growth curve parameters and their first derivatives, respectively. Results: Linear and nonlinear curve parameters differed significantly between race-sex groups. BP showed race and sex differences from age 15 years onwards. Adults with LVH had higher long-term BP levels than normal adults in race-sex groups. Linear and nonlinear slope parameters of BP differed consistently, significantly between LVH and normal groups. Level-independent linear slopes of systolic BP showed significantly negative associations (odds ratio=0.75~0.82, p=0.001~0.015) during pre-puberty period of 4-9 years but significantly positive associations (odd ratio=1.29~1.46, p=0.001~0.008) during the puberty period of 13-19 years with adult LVH, adjusting for covariates (see the figure below). These associations were consistent across race-sex groups. Of note, the association of childhood BP linear slopes with concentric LVH was significantly stronger than that with eccentric LVH during the puberty period of 12-19 years. Conclusions: These observations indicate that the impact of BP trajectories on adult LVH and geometric patterns originates in childhood. Puberty is a crucial period for the development of LVH in later life, which has implications for early prevention.

Effect of home telehealth care on blood pressure control: A public healthcare centre model

Objective This study aimed to evaluate the effectiveness of home telehealth care combined with case management by public health nurses, in improving blood pressure control in patients with hypertension. Methods This cohort study examined the data of patients with hypertension obtained from a telehealth service centre database, between July 2011– June 2012. Eligible patients were adults (≥40 years old) with both prehypertension and hypertension, living alone or in the remote suburbs of metropolitan areas. Demographic data were collected from 12 district public health centre in Taipei, Taiwan. Following enrolment, patients received an appropriate and validated home telehealth device kit for automatic blood pressure monitoring and automated modem via a telephone line or a desktop computer with Internet connection to enable data transmission between the patient’s home and telehealth service centre. Patients were instructed to upload the measured data immediately every day. The study outcomes included blood pressure and home telehealth service utilisation. Results Of the 432 patients recruited, 408 (94%) completed data collection. Linear regression analysis found an average 22.1 mm Hg reduction in systolic blood pressure after one year. The mean slope of systolic blood pressure was classified as decreased or non-decreased. An systolic blood pressure decreasing trend was observed in 52.2% patients, while 47.8% patients showed an increasing systolic blood pressure trend. Patients in the decreased systolic blood pressure group tended to be older (p = 0. 0001), with a greater proportion of hypertension alarms (p = 0. 001), improved self-blood pressure monitoring behaviour (p = 0.009) and higher self-measured blood pressure monitoring frequency (p = 0. 010). Patients in the decreased systolic blood pressure group had a higher self-measured blood pressure monitoring frequency (odds ratio = 0.95, 95% confidence interval, 0.91–0.99, p = 0. 013) than their counterparts. Conclusions Home telehealth care combined with care management by public health nurses based in public health care centre was feasible and effective for improving blood pressure control among patients with hypertension. Further studies should conduct a thorough analysis of the cost-effectiveness of this intervention. A randomised controlled trial with a longer follow-up period is required to examine the effects of the improved home telehealth device kit on the care of patients with hypertension.

Endothelial Dysfunction Predicts Systolic Blood Pressure Slope During Whole Body Maximal Exercise In Patients With Chronic Kidney Disease

Chronic kidney disease (CKD) patients have exercise intolerance and poor physical capacity that increases the risk of adverse cardiovascular events during and after physical activity. Previous studies in our lab demonstrate that CKD patients have exaggerated increases in blood pressure (BP) and sympathetic nervous system activation during handgrip exercises. However, whether CKD patients also have exaggerated increases in BP during whole‐body exercise or high intensity exercise is unknown. Furthermore, CKD patients often have endothelial dysfunction which could potentially lead to an impaired ability to vasodilate during exercise. Whether this might contribute to the augmented pressor response in CKD is also unknown. We hypothesized that CKD patients have exaggerated increases in BP during maximal whole body exercise and that endothelial dysfunction predicts a greater pressor response during exercise in these patients. 56 participants (35 CKD, 21 age‐matched controls) underwent maximal treadmill exercise using the modified Balke protocol. BP, heart rate (HR), and rate of perceived exertion were continuously monitored. Levels of mixed expired oxygen, carbon dioxide, and ventilation were recorded at rest and every 30 seconds during exercise. The peak oxygen uptake (VO2 max) was defined as the highest VO2 rate observed during maximal exercise. Endothelial function was assessed via brachial artery flow‐mediated dilation (FMD) just before and repeated 1 hour after exercise. CKD patients had significantly lower VO2 max compared to controls (21.8±1.1 ml/min/kg vs. 30.3±1.7, p&lt;0.001). There was no significant difference in maximal systolic BP (SBP), diastolic BP, or mean arterial pressure achieved during exercise between groups. However, CKD patients had a greater slope of rise in SBP (10.3 mmHg/stage vs. 7.7, p&lt;0.001). Maximum achieved HR was significantly lower in CKD versus controls (134.9±4.4 bpm vs. 150.0±3.6, p=0.011). Similar to BP response, the slope of rise in HR was significantly steeper in CKD patients (11.9 bpm/stage vs. 10.7, p=0.032). Before exercise, FMD (2.76±0.42% vs. 5.84±0.97, p=0.007), and FMD controlled for peak shear rate (FMDshear) (4.01±0.62% vs. 6.85±1.11, p=0.033) were significantly lower in CKD patients. A lower pre‐exercise FMD (p=0.039) and FMDshear (p&lt;0.001) were significantly associated with a greater slope of rise in SBP during exercise in CKD, but not in controls. There was no significant change in FMD before and after exercise in either group. CKD patients exhibit an accelerated rise in SBP and HR during whole body maximal exercise compared to controls. Further, impaired FMD predicts an accelerated SBP and HR response during exercise in CKD patients, but not in controls. These data suggest that endothelial dysfunction is associated with the exaggerated pressor response during exercise in CKD patients.Support or Funding InformationSupported by NIH HL‐098744.

Effects of urban fine particulate matter and ozone on HDL functionality

BackgroundExposures to ambient particulate matter (PM) are associated with increased morbidity and mortality. PM2.5 (<2.5 μm) and ozone exposures have been shown to associate with carotid intima media thickness in humans. Animal studies support a causal relationship between air pollution and atherosclerosis and identified adverse PM effects on HDL functionality.We aimed to determine whether brief exposures to PM2.5 and/or ozone could induce effects on HDL anti-oxidant and anti-inflammatory capacity in humans.MethodsSubjects were exposed to fine concentrated ambient fine particles (CAP) with PM2.5 targeted at 150 μg/m3, ozone targeted at 240 μg/m3 (120 ppb), PM2.5 plus ozone targeted at similar concentrations, and filtered air (FA) for 2 h, on 4 different occasions, at least two weeks apart, in a randomized, crossover study. Blood was obtained before exposures (baseline), 1 h after and 20 h after exposures. Plasma HDL anti-oxidant/anti-inflammatory capacity and paraoxonase activity were determined. HDL anti-oxidant/anti-inflammatory capacity was assessed by a cell-free fluorescent assay and expressed in units of a HDL oxidant index (HOI). Changes in HOI (ΔHOI) were calculated as the difference in HOI from baseline to 1 h after or 20 h after exposures.ResultsThere was a trend towards bigger ΔHOI between PM2.5 and FA 1 h after exposures (p = 0.18) but not 20 h after. This trend became significant (p <0.05) when baseline HOI was lower (<1.5 or <2.0), indicating decreased HDL anti-oxidant/anti-inflammatory capacity shortly after the exposures. There were no significant effects of ozone alone or in combination with PM2.5 on the change in HOI at both time points. The change in HOI due to PM2.5 showed a positive trend with particle mass concentration (p = 0.078) and significantly associated with the slope of systolic blood pressure during exposures (p = 0.005).ConclusionsBrief exposures to concentrated PM2.5 elicited swift effects on HDL anti-oxidant/anti-inflammatory functionality, which could indicate a potential mechanism for how particulate air pollution induces harmful cardiovascular effects.Electronic supplementary materialThe online version of this article (doi:10.1186/s12989-016-0139-3) contains supplementary material, which is available to authorized users.

Immediate post-isometric exercise cardiovascular responses are associated with training-induced resting systolic blood pressure reductions.

The purpose of this study was twofold: (1) to investigate the effect of 4 weeks of bilateral-leg isometric exercise training on the immediate isometric post-exercise cardiovascular responses, and (2) to ascertain whether any changes in immediate post-exercise cardiovascular responses may be associated with training-induced adaptations in resting blood pressure. Thirteen normotensive males completed both isometric exercise training (IET) and control conditions, which were separated by 6 weeks. Participants performed a total of twelve training sessions; 4 × 2-min bilateral-leg isometric exercise bouts separated by 3-min rest periods, 3 days week(-1). Four weeks of bilateral-leg IET resulted in a reduction in resting SBP (120 ± 12-115 ± 12 mmHg, p = 0.01). The intercept of the 5-min post-exercise systolic blood pressure slope was lower (p = 0.015) following the 4-week training intervention. Individual changes in immediate post-exercise response SBP were also significantly correlated with reductions in resting SBP following 4 weeks of training. There were significant differences in the slopes of the first vs. final post-exercise BRS response (p = 0.009), and the intercepts of the HRR slopes (p = 0.04) recorded during the 5-min post-exercise periods. Four weeks of IET altered immediate cardiovascular responses to an individual IET session. Altered immediate responses were also associated with training-induced reductions in resting SBP. To our knowledge, this is the first evidence suggesting that very short-term (immediate) cardiovascular responses may be important in defining chronic reductions in resting blood pressure following a period of IET.

Early Systolic Blood Pressure Changes in Incident Hemodialysis Patients Are Associated with Mortality in the First Year

Background: In incident hemodialysis (HD) patients, the relationship between early systolic blood pressure (SBP) dynamics and mortality is unknown. Methods: Baseline SBP levels were stratified into 5 categories ranging from <120 and ≥180 mm Hg. Early pre-HD SBP change was defined as the slope of pre-HD SBP from week 1 to 12 and categorized in quartiles (Q1, lowest slope). SBP slopes were computed for each patient by simple linear regression. Results: In 3,446 incident HD patients (42% females, 44% black, age 62 ± 15 years), the median pre-HD SBP slope was –1.7 (Q1) to +2.3 (Q4) mm Hg/week. In an adjusted multivariate Cox regression analysis, patients with declining SBP (slope Q1) had higher mortality compared to patients with increasing pre-HD SBP (slope Q4) at 12 months (hazard ratio 2.01, 95% confidence interval 1.35–3.01). In addition, patients with baseline pre-HD SBP <120 mm Hg showed higher mortality compared to the reference group (SBP ≥180 mm Hg) at 12 months (hazard ratio 1.89, 95% confidence interval 1.03–3.45). Conclusion: Baseline pre-HD SBP and early SBP dynamics are associated with mortality in the first year of dialysis. Patients who had low (pre-HD SBP <120 mm Hg) or declining SBP had the highest mortality rates. Particular attention is warranted in incident HD patients with low or declining SBP.

Genome-wide linkage scan for genes affecting longitudinal trends in systolic blood pressure.

Only one genome scan to date has attempted to make use of the longitudinal data available in the Framingham Heart Study, and this attempt yielded evidence of linkage to a gene for mean systolic blood pressure. We show how the additional information available in these longitudinal data can be utilized to examine linkages for not only mean systolic blood pressure (SBP), but also for its trend with age and its variability. Prior to linkage analysis, individuals treated for hypertension were adjusted to account for right-censoring of SBP. Regressions on age were fitted to obtain orthogonal measures of slope, curvature, and residual variance of SBP that were then used as dependent variables in the model-free linkage program SIBPAL. We included mean age, gender, and cohort as covariates in the analysis. To improve power, sibling pairs were weighted for informativity using weights derived from both the marker and trait. The most significant results from our analyses were found on chromosomes 12, 15, and 17 for mean SBP, and chromosome 20 for both SBP slope and curvature.

Long working hours and risk for hypertension in Japanese male white collar workers

STUDY OBJECTIVETo evaluate the association of long working hours with the risk for hypertension.DESIGNA five year prospective cohort study.SETTINGWork site in Osaka, Japan.PARTICIPANTS941 hypertension free Japanese male white collar workers...

The INTERSALT Study: background, methods, findings, and implications

The INTERSALT Study is a standardized, worldwide epidemiologic study of large sample size (n = 10079 men and women aged 20-59 y from 32 countries) that tested both within- and cross-population prior hypotheses on 24-h sodium excretion and blood pressure. For individuals, a significant, positive, independent linear relation between 24-h sodium excretion and systolic blood pressure (SBP) was found. With multivariate adjustment for underestimation, the estimated effect of a sodium intake higher by 100 mmol/d was higher SBP/DBP (diastolic blood pressure) by approximately 3-6/0-3 mm Hg. This relation prevailed for both men and women, for younger and older people, and for 8344 people without hypertension. In tests of prior cross-population hypotheses (n = 52), significant, independent relations were found between sample 24-h median urinary sodium excretion and sample median SBP and DBP, prevalence rate of hypertension, and slope of SBP and DBP from age 20 to 59 y (median sodium intake greater by 100 mmol/d was associated with a 30-y increase in SBP/DBP, i.e., at the age of 55 y compared with 25 y, of 10-11/6 mm Hg. The INTERSALT results, which agree with findings from other diverse studies, including data from clinical observations, therapeutic interventions, randomized controlled trials, animal experiments, physiologic investigations, evolutionary biology research, anthropologic research, and epidemiologic studies, support the judgment that habitual high salt intake is one of the quantitatively important, preventable mass exposures causing the unfavorable population-wide blood pressure pattern that is a major risk factor for epidemic cardiovascular disease.

Association of genetic variation with interindividual variation in ambulatory blood pressure

To determine whether genetic and non-genetic components of interindividual variation in systolic and diastolic blood pressure are constant throughout the day or are time or activity dependent. We obtained 24 h ambulatory blood pressure recordings in 263 members of 68 unrelated nuclear families (i.e. parents and their offspring) representative of the Caucasian population of Rochester, MN, USA. Using the time each patient got into bed as a reference point, we identified 198 records in which this reference point was preceded by eight consecutive active hours (out of bed) and followed by four consecutive inactive hours (in bed) in which four or more blood pressure readings taken each hour were judged to be technically satisfactory. For each hourly mean for systolic and diastolic blood pressure, we estimated total interindividual variance, variance associated with concomitant variables (generation; sex within generation strata; and age, height, weight, body mass index, and abdomen-to-hip ratio within generation and sex strata), and variance associated with additive genetic effects (i.e. the chief cause of resemblance between relatives). To assess trends in each component of interindividual blood pressure variance over the 12 h period, we estimated the slope of the linear regression line fit to the hourly estimates. For systolic blood pressure, total interindividual variance did not change significantly (slope of regression line = -0.23, P = 0.717). In contrast, total interindividual variance for diastolic blood pressure was greater during active hours than inactive hours (slope of regression line = -5.53, P < 0.001). For both systolic and diastolic blood pressure, variance associated with the concomitant variables was greater during active hours than during inactive hours (for systolic blood pressure slope of regression line = -2.98, P = 0.001; for diastolic blood pressure slope of regression line = -6.14, P < 0.001). Likewise, for both systolic and diastolic blood pressure, variance associated with additive genetic effects was also greater during active hours than during inactive hours (for systolic blood pressure slope of regression line = -1.65, P = 0.090; for diastolic blood pressure slope of regression line = -1.47, P = 0.018). This study demonstrates that components of interindividual variation in blood pressure are not constant, but are time or activity dependent.