Postural Change In Systolic Blood Pressure Research Articles

Association of general and abdominal adiposity with postural changes in systolic blood pressure: results from the NAKO pretest and MetScan studies

The association between anthropometric measurements and postural changes in systolic blood pressure (SBP) has not been frequently reported. This study aimed to investigate the association of body mass index (BMI) and waist circumference (WC) with postural changes in SBP in two German cross-sectional studies. Data were derived from 506 participants of the population-based German National Cohort (NAKO) pretest and from 511 participants of the convenience sample-based MetScan studies. Linear regression models were used to estimate the association between BMI and WC with the difference between standing and sitting SBP (dSBP). Odds ratios (ORs) for an increase (dSBP > 10 mmHg) or decrease (dSBP ≤ −10 mmHg) in dSBP were calculated using logistic regression. The results were pooled by meta-analysis using an inverse variance model. In pooled analysis, a 5 kg/m2 higher BMI was associated with a 1.46 mmHg (95% confidence interval (CI) 0.98–1.94) higher dSBP, while a 5 cm higher WC was associated with a 0.51 mmHg (95% CI 0.32–0.69) higher dSBP. BMI or WC were associated with a higher odds of an increase in dSBP (adjusted OR, 1.71; 95% CI 1.36–2.14 per 5 kg/m2 higher BMI and 1.22; 95% CI 1.05–1.40 per 5 cm higher WC) but with a reduced odds of a decline in dSBP (adjusted OR, 0.67; 95% CI 0.44–1.00 per 5 kg/m2 higher BMI and 0.84; 95% CI 0.72–0.99 per 5 cm higher WC). The associations between WC and dSBP were no longer statistically significant after BMI adjustments. In conclusion, higher BMI and higher WC were associated with higher postural increases in SBP; however, WC was not related to postural changes in SBP once adjusted for BMI.

Hypertension Treatment Effects on Orthostatic Hypotension and Its Relationship With Cardiovascular Disease.

Although orthostatic hypotension (OH) is often considered a contraindication to blood pressure (BP) treatment, evidence is lacking. We examined the effect of BP goal or initial medication choice on OH in AASK (African American Study of Kidney Disease and Hypertension), a 2×3 factorial trial. Blacks with chronic kidney disease attributed to hypertension were randomly assigned 1 of 2 BP goals: intensive (mean arterial pressure, ≤92 mm Hg) or standard (mean arterial pressure, 102-107 mm Hg) and 1 of 3 initial medications (ramipril, metoprolol, and amlodipine). Postural changes in systolic BP, diastolic BP, or heart rate (HR) were determined after 2 minutes and 45 seconds of standing. OH was assessed each visit and defined using the consensus definition (drop in systolic BP ≥20 mm Hg or diastolic BP ≥10 mm Hg). Median follow-up was 4 years. Outcomes were congestive heart failure, stroke, nonfatal cardiovascular disease (CVD), fatal CVD, any CVD (composite of preceding events), and all-cause mortality. There were 1094 participants (mean age, 54.5±10.7 years; 38.8% female; OH was assessed at 52 864 visits). Mean seated systolic BP, diastolic BP, and HR were 150.3±23.9 mm Hg, 95.5±14.2 mm Hg, and 72.0±12.6 bpm, respectively. A more intensive BP goal did not alter the distributions of standing BP and was not associated with OH, but metoprolol was associated with systolic OH compared with ramipril (odds ratio, 1.68; 95% CI, 1.15-2.46) and amlodipine (odds ratio, 1.94; 95% CI, 1.09-3.44). Although consensus OH was associated with stroke (HR, 5.01; 95% CI, 1.80-13.92), nonfatal CVD (HR, 2.28; 95% CI, 1.21-4.30), and any CVD event (HR, 2.12; 95% CI, 1.12-3.98), neither BP goal or medication altered this risk. Concerns about causing OH or its CVD consequences should not deter a lower BP goal among adults with chronic kidney disease attributed to hypertension.

Orthostatic Hypotension in Middle-Age and Risk of Falls.

One-third of older adults fall each year. Orthostatic hypotension (OH) has been hypothesized as an important risk factor for falls, but findings from prior studies have been inconsistent. We conducted a prospective study of the association between baseline OH (1987-1989) and risk of falls in the Atherosclerosis Risk in Communities (ARIC) Study. Falls were ascertained during follow-up via ICD-9 hospital discharge codes or Centers for Medicare & Medicaid Services claims data. OH was defined as a drop in systolic blood pressure (SBP) ≥20mm Hg or diastolic blood pressure (DBP) ≥10mm Hg within 2 minutes of moving from the supine to standing position. Changes in SBP or DBP during OH assessments were also examined as continuous variables. During a median follow-up of 23 years, there were 2,384 falls among 12,661 participants (mean age 54 years, 55% women, 26% black). OH was associated with risk of falls even after adjustment for demographic characteristics and other risk factors (hazard ratio (HR): 1.30; 95% confidence interval (CI): 1.10, 1.54; P = 0.002). Postural change in DBP was more significantly associated with risk of falls (HR 1.09 per -5mm Hg change in DBP; 95% CI: 1.05, 1.13; P < 0.001) than postural change in SBP (HR 1.03 per -5mm Hg change in SBP; 95% CI: 1.01, 1.05; P = 0.002). In a community-based, middle-aged population, OH, and in particular, postural change in DBP, were independent risk factors for falls over 2 decades of follow-up. Future studies are needed to examine OH thresholds associated with increased risk of falls.

Association between body anthropometric parameters and indices of cardiac autonomic function among apparently healthy young adults

Background: Anthropometric parameters are useful for indexing cardiovascular variables. Objectives: This study aimed at determining the association between anthropometric parameters and autonomic cardiovascular indices (ACIs) among young adults. Materials and Methods: It was a cross-sectional descriptive study involving 204 healthy young adults who were residents of Ile-Ife. The weight (kg) and height (m) were measured with health scale while body mass index and body surface area were calculated using Quetelet index and Mosteller formula, respectively. Each participant was evaluated through a battery of procedures; systolic blood pressure (SBP) response to standing, diastolic blood pressure (DBP) response to sustained handgrip (SH), resting heart rate (RHR), heart rate (HR) variability during Valsalva maneuver, deep breathing, and change of posture while the ACIs were derived as outcome of the procedures. The relationship between the anthropometry and ACI was determined by correlation. Results: Height positively correlated with SBP response to posture (r = 0.107, P = 0.128), DBP response to SH (r = 0.143, P = 0.041), and heart rate response to deep breathing (HDB) (r = 0.043, P = 0.540). Height negatively correlated with Valsalva ratio (r = −0.022, P = 0.759), 30:15 ratio (r = −0.009, P = 0.902), and RHR (−0.152, P = 0.030). Weight correlated positively with postural change in SBP (r = 0.096, P = 0.172), DBP response to SH (r = 0.091, P = 0.197), and 30:15 ratio (r = 0.005, P = 0.948). Weight negatively correlated with HR response to deep breathing (r = −0.114, P = 0.105) and RHR (r = −0.153, P = 0.029). Conclusion: Anthropometric parameters correlated weakly with most indices of cardiac autonomic function except RHR.

Effects of Patient-Controlled Abdominal Compression on Standing Systolic Blood Pressure in Adults With Orthostatic Hypotension

ObjectiveTo assess the effects of patient-controlled abdominal compression on postural changes in systolic blood pressure (SBP) associated with orthostatic hypotension (OH). Secondary variables included subject assessments of their preferences and the ease-of-use. DesignRandomized crossover trial. SettingClinical research laboratory. ParticipantsAdults with neurogenic OH (N=13). InterventionsFour maneuvers were performed: moving from supine to standing without abdominal compression; moving from supine to standing with either a conventional or an adjustable abdominal binder in place; application of subject-determined maximal tolerable abdominal compression while standing; and while still erect, subsequent reduction of abdominal compression to a level the subject believed would be tolerable for a prolonged period. Main Outcome MeasuresThe primary outcome variable included postural changes in SBP. Secondary outcome variables included subject assessments of their preferences and ease of use. ResultsBaseline median SBP in the supine position was not affected by mild (10mmHg) abdominal compression prior to rising (without abdominal compression: 146mmHg; interquartile range, 124–164mmHg; with the conventional binder: 145mmHg; interquartile range, 129–167mmHg; with the adjustable binder: 153mmHg, interquartile range, 129–160mmHg; P=.85). Standing without a binder was associated with an −57mmHg (interquartile range, −40 to −76mmHg) SBP decrease. Levels of compression of 10mmHg applied prior to rising with the conventional and adjustable binders blunted these drops to −50mmHg (interquartile range, −33 to −70mmHg; P=.03) and −46mmHg (interquartile range, −34 to −75mmHg; P=.01), respectively. Increasing compression to subject-selected maximal tolerance while standing did not provide additional benefit and was associated with drops of −53mmHg (interquartile range, −26 to −71mmHg; P=.64) and −59mmHg (interquartile range, −49 to −76mmHg; P=.52) for the conventional and adjustable binders, respectively. Subsequent reduction of compression to more tolerable levels tended to worsen OH with both the conventional (−61mmHg; interquartile range, −33 to −80mmHg; P=.64) and adjustable (−67mmHg; interquartile range, −61 to −84mmHg; P=.79) binders. Subjects reported no differences in preferences between the binders in terms of preference or ease of use. ConclusionsThese results suggest that mild (10mmHg) abdominal compression prior to rising can ameliorate OH, but further compression once standing does not result in additional benefit.

Efficacy and Safety of Aldose Reductase Inhibitor for the Treatment of Diabetic Cardiovascular Autonomic Neuropathy: Systematic Review and Meta-Analysis

BackgroundAldose reductase inhibitors (ARIs) can block the metabolism of the polyol pathway, and have been used to slow or reverse the progression of diabetic cardiovascular autonomic neuropathy (DCAN). The purpose of this study was to review the effectiveness and safety of ARIs in the treatment of DCAN as determined by five cardiac autonomic neuropathy function tests.MethodsCENTRAL, MEDLINE, EMBASE, Scopus databases (inception to May 2012) were searched to identify randomized controlled trials (RCTs) and non-randomized controlled trials (non-RCTs) investigating ARIs for the treatment of DCAN with an English-language restriction. The data were analyzed using RevMan 5.0, and the heterogeneity between the trials was evaluated using the Cochrane's Q-test as well as the I2 test. The type of model (random or fixed) used for analysis was based on heterogeneity. Weighted mean differences (WMD) with 95% confidence intervals (CI) were computed for the five cardiac automatic neuropathy function tests to evaluate the effects.ResultsTen articles met the prerequisites for this review. Analysis of the results showed that ARIs significantly improved function in at least three of the five automatic neuropathy tests, including the resting heart rate variation coefficients (WMD = 0.25, 95%CI 0.02 to 0.48, P = 0.040); the 30∶15 ratio (WMD = 0.06, 95%CI 0.01 to 0.10, P = 0.010) and the postural systolic blood pressure change (WMD = −5.94, 95%CI −7.31 to −4.57, P = 0.001). The expiration/inspiration ratio showed a marginally significant benefit (WMD = 0.05, 95%CI 0.00 to 0.09, P = 0.040). Glycaemic control was not significantly affected by ARIs. Adverse effects of ARIs except for Tolerestat were minimal.ConclusionsBased on these results, we conclude that ARIs could ameliorate cardiac automatic neuropathy especially mild or asymptomatic DCAN but need further investigation.

Orthostatic Hypotension Is Associated With Nocturnal Change in Systolic Blood Pressure

The circadian pattern of blood pressure (BP) has yet to be defined among individuals with orthostatic hypotension (OH). The objective of this study was to evaluate whether OH is associated with nocturnal change in systolic BP. In a prospective study, we evaluated patients who were referred for 24-h ambulatory blood pressure monitoring (ABPM). All subjects underwent orthostatic BP testing before recording their respective 24-h ABPM. The study includes 185 subjects, 114 males, mean age 58 ± 18 years (range 19-89). Participants were classified, based on pattern of systolic BP changes at night, as dippers (greater than 10% decrease; n = 74), nondippers (0-10% decrease; n = 77), and reverse-dippers (increase; n = 34). Nineteen patients (10.3%) had OH. Almost all participants with OH (95%) had an abnormal diurnal BP pattern, and most of them (58%) were reverse-dippers, whereas only 56% of the participants without OH had an abnormal diurnal BP variation, and only 14% were reverse-dippers (P < 0.001). Systolic BP decreased with upright posture by 12 and 2 mm Hg in the reverse-dippers and the nondippers, respectively, and increased by 2 mm Hg in the dippers (P < 0.001). Postural changes in systolic BP were inversely related to the changes between day and night BP readings(r = -0.43; P < 0.01). In a multivariate linear regression analysis, orthostatic BP change, use of ≥2 antihypertensive drugs and female sex were related to nocturnal BP changes. The decrease in BP during upright posture may be a marker of nondipping or reverse-dipping pattern of diurnal BP.

Genes controlling postural changes in blood pressure: comprehensive association analysis of ATP-sensitive potassium channel genes KCNJ8 and ABCC9

Buffering of blood pressure during change of posture such as standing is controlled largely by the baroreflex. In our population-based Victorian Family Heart Study (VFHS), we previously demonstrated that, on average, systolic blood pressure (SBP) changes very little on standing; however, interindividual variation is substantial and shows familial aggregation, with approximately 25% of the variance attributable to genetic factors. Our genomewide linkage analysis suggests a region on chromosome 12p that harbors two strong candidate genes, KCNJ8 and ABCC9, encoding the channel-forming inward rectifier subunit Kir6.1 and the ATP-sensitive binding cassette SUR2B, respectively. These are key components of smooth muscle ATP-sensitive potassium (K(ATP)) channels, important regulators of arterial tone and blood flow and central to autonomic baroreceptor control of changes in total peripheral resistance. We performed a comprehensive association analysis of 47 tag single nucleotide polymorphisms (SNPs) spanning the KCNJ8 and ABCC9 gene regions with postural change in SBP (DeltaSBP). To augment power, we took a selective genotyping approach in which we compared allele and genotype frequencies between 150 unrelated individuals with high (positive) DeltaSBP (> or = 7 mmHg) and 150 unrelated individuals with low (negative) DeltaSBP (< or = -7 mmHg) drawn from the offspring generation (18-30 yr) of the VFHS. Association analyses showed that no SNPs demonstrated statistically significant differences in genotype frequencies between groups, particularly after adjustments for multiple testing. We conclude that sequence variants in KCNJ8 and ABCC9 are unlikely to contribute to variation in DeltaSBP. Other genes in the identified chromosome 12p region warrant investigation.

Further Evidence of a Quantitative Trait Locus on Chromosome 18 Influencing Postural Change in Systolic Blood Pressure: The Hypertension Genetic Epidemiology Network (HyperGEN) Study

Postural change in systolic blood pressure (SBP) is prospectively associated with several disease outcomes including hypertension, stroke, and coronary heart disease. The objective of this study was to characterize further a possible quantitative trait locus on chromosome 18q21 influencing SBP response to a postural challenge. A prior genome scan of postural SBP response in 636 subjects of white ethnicity from 285 hypertensive sibships in the Hypertension Genetic Epidemiology Network (HyperGEN) indicated suggestive evidence for linkage on chromosome 18q21. This study included a de novo set of 452 African American pedigrees from the HyperGEN study and an expanded set of 372 white pedigrees. Variance components linkage analysis of postural SBP change was conducted using microsatellite markers on chromosome 18, and association studies were performed with a common single nucleotide polymorphism (variant 13) in the gene encoding NEDD4L, a key regulator of fine sodium reabsorption in the distal nephron. Combined analysis of all white and African American pedigrees yielded a LOD score of 4.25 at 80 cM on chromosome 18q21, with at least nominal evidence of linkage at this position in both white (LOD: 3.43) and African American (LOD: 1.14) subjects. Postural SBP response was associated with variant 13 of the NEDD4L in a subset of white subjects taking medications effective in treating sodium volume-dependent hypertension (alpha1-blockers, calcium channel blockers, and/or diuretics). These data provide further evidence for a quantitative trait locus on chromosome 18q21 influencing postural change in SBP.

Postural dysregulation in systolic blood pressure is associated with worsened scoring on neurobehavioral function tests and leukoaraiosis in the older elderly living in a community.

Postural hypotension, which occurs frequently in community-living, apparently healthy elderly adults, is usually asymptomatic. However, the relation between postural changes in blood pressure and quantitative higher cerebral function or silent brain lesions remains unclear. We examined the association of exaggerated postural changes in systolic blood pressure with cognitive and quantitative neurobehavioral functions and with brain lesions on MRI in the community-dwelling older elderly. The study population consisted of 334 community-dwelling elderly adults, aged 75 years or older (mean age, 80 years). Postural changes in systolic blood pressure (SBP) were assessed using an autosphygmomanometer (BP-203 I). By the difference between the mean of two measurements of SBP at standing and at supine position (dSBP = SBP at upright-SBP at supine position), we divided the subjects into three groups: (1) 20 subjects with postural hypotension (d-SBP < or = -20 mm Hg), (2) 29 subjects with postural hypertension (dSBP > or = 20 mm Hg), and (3) 285 subjects with postural normotension (20 < dSBP < 20 mm Hg). We defined the former two groups as the postural dysregulation group. Scores in four neurobehavioral function tests (Mini-Mental State Exam. Hasegawa Dementia Scale Revised, computer-assisted visuospatial cognitive performance score, and the Up and Go Test) and activities of daily living were compared among the three groups. Brain lesions on MRI, including number of lacunes and periventricular hyperintense lesions, were compared among 15 age- and sex-matched control subjects with postural hypotension, 15 with postural hypertension, and 30 with postural normotension. Twenty subjects (6.0%) exhibited postural hypotension and 29 (8.7%) postural hypertension. Scores in neurobehavioral functions and activities of daily living were significantly lower in the postural dysregulation group (both postural hypotension and hypertension groups) than in the postural normotension group. The postural dysregulation group exhibited significantly more advanced periventricular hyperintensities than the normotension group. Asymptomatic community dwelling elderly individuals with postural hypotension as well as those with postural hypertension had poorer scores on neurobehavioral function tests and more advanced leukoaraiosis demonstrated on MRI than those without exaggerated postural changes in SBP.

Portable infrared pupillometry using Pupilscan: relation to somatic and autonomic nerve function in diabetes mellitus.

The relationship between dynamic pupillary function and peripheral nerve function was studied in 85 randomly-selected diabetic patients and 67 age-matched normals using a portable infrared pupillometer (Pupilscan Version 5). Seven measurements were chosen to represent different components of the pupillary constriction-redilatation curve after a standardized light stimulus. Constriction latency was significantly prolonged in diabetic patients (p = 0.05), as was time to 63% redilatation (p = 0.001). Thermal thresholds at the feet weakly correlated with relative reflex amplitude (warm: r = -0.22, p = 0.05; cool: r = -0.23, p = 0.05), but vibration perception thresholds were more strongly associated with constriction and redilatation velocity (r = -0.42, p = 0.001; r = -0.28, p = 0.03). Among the cardiovascular autonomic function tests, only respiratory R-R variation correlated with constriction velocity (r = 0.47, p < 0.001), and Valsalva ratio with redilatation velocity (r = 0.25, p = 0.04), but postural systolic blood pressure change was also correlated with reflex amplitude and latency time (r = -0.42, p < 0.001; r = 0.41, p = 0.001). There were no significant associations with three measures of sweating function in the feet. Pupil measurements were abnormal in 4-11% of diabetic patients, while other neurological tests were abnormal in 8-35%, consistent with the length-dependence of diabetic neuropathy. Median coefficients of variation were 2.0-7.2% in diabetic patients.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of caffeine on postprandial blood pressure in the frail elderly

In a double-blind, random-order, cross-over study the effects of placebo and 100 mg of caffeine on postprandial sitting and erect blood pressure and heart rate were studied in 20 frail elderly subjects (mean age 84, range 75-93 years) after a standardized 400 K-calorie glucose drink. Maximal postprandial reduction in sitting systolic blood pressure occurred, at 60 minutes post-placebo, of - 11 mmHg (95% confidence interval -5 to -17 mmHg, P less than 0.01), and was attenuated by caffeine (P less than 0.05) with changes in systolic blood pressure, at 60 minutes post-drink, of 1 mmHg (95% CI -6 to 7 mmHg, not significant). Four subjects developed symptomatic postprandial hypotension after placebo which was prevented by caffeine. There were no significant changes in erect systolic blood pressure, postural systolic blood pressure change, sitting and erect, diastolic blood pressure and heart rate between treatment phases. Caffeine attenuates the postprandial fall in sitting blood pressure in frail elderly subjects and in particular prevented symptomatic blood pressure reductions in subjects with postprandial hypotension.

Intra-individual variability in postural blood pressure in the elderly.

Orthostatic hypotension, an age-related phenomenon, has been associated with hypertension and body weight variability. To evaluate the relative contributions of blood pressure elevation and abnormalities in extracellular volume regulation to orthostatic hypotension, elderly institutionalized subjects (mean age = 87 +/- 7 years), taking no cardiovascular medications, underwent measurement of body weight (n = 15) and first morning supine and standing blood pressures (n = 19), 12-13 times per subject over a 2-4 week period. There was a wide day-to-day variability in postural systolic blood pressure change (coefficient of variation = 533%) and a strong negative correlation between each day's postural change in systolic blood pressure and basal supine blood pressure (r = -0.55, P less than 0.0001). There was no association between postural blood pressure change and heart rate response or body weight changes, which were very small over the duration of the study (coefficient of variation = 0.6%). Elderly individuals have intact homeostatic mechanisms for the control of standing pressure when basal blood pressure is normal. Postural hypotension in the elderly is a variable phenomenon related to elevations in basal blood pressure.