Orthostatic Changes Research Articles

Leg pain in neuropathic postural tachycardia syndrome is associated with altered muscle membrane properties

PurposeIn neuropathic postural tachycardia syndrome, peripheral sympathetic dysfunction leads to excessive venous blood pooling during orthostasis. Up to 84% of patients report leg pain and weakness in the upright position. To explore possible pathophysiological processes underlying these symptoms, the present study examined muscle excitability depending on body position in patients with neuropathic postural tachycardia syndrome and healthy subjects.MethodsIn ten patients with neuropathic postural tachycardia syndrome and ten healthy subjects, muscle excitability measurements were performed repeatedly: in the supine position, during 10 min of head-up tilt and during 6 min thereafter. Additionally, lower leg circumference was measured and subjective leg pain levels were assessed.ResultsIn patients with neuropathic postural tachycardia syndrome, muscle excitability was increased in the supine position, decreased progressively during tilt, continued to decrease after being returned to the supine position, and did not completely recover to baseline values after 6 min of supine rest. The reduction in muscle excitability during tilt was paralleled by an increase in lower leg circumference as well as leg pain levels. No such changes were observed in healthy subjects.ConclusionsThis study provides evidence for the occurrence of orthostatic changes in muscle excitability in patients with neuropathic postural tachycardia syndrome and that these may be associated with inadequate perfusion of the lower extremities. Insufficient perfusion as a consequence of blood stasis may cause misery perfusion of the muscles, which could explain the occurrence of orthostatic leg pain in neuropathic postural tachycardia syndrome.

P159 Successful treatment of sleep disordered breathing improves comorbidities in patients with nocturia

Abstract Introduction Sleep disordered breathing (SDB) has been shown to increase nocturia (waking with the need to void urine) frequency. Nocturia negatively affects sleep, autonomic dysfunction, mental health and mortality. Nocturia and these co-morbidities share central control areas in the brainstem. We hypothesised that treatment of SDB would decrease nocturia frequency and impact these co-morbidities. Methods A prospective repeated measures study with participants ≥40 years, naïve to treatment, with an AHI ≥30/hr and experiencing ≥1 episodes of nocturia was conducted. Participants undertook two months of CPAP with before and after measures of lower urinary tract symptoms (Overactive Bladder Symptom Score (OABSS) and urine volume), sleep quality (PSQI and actigraphy), autonomic dysfunction (blood pressure and orthostatic change) and wellbeing (Nocturia quality of life score (NQoL) and the Hospital anxiety and depression scores (HADS)). Results 490 diagnostic studies screened, 36 patients met criteria, and 30 participants (57% male) were recruited. 15 patients completed treatment with 55% of completed participants meeting the required compliance of >4 hours. Significant changes in OABSS (p=0.035), nocturnal voiding frequency (p=0.007), nocturnal urine volume (p=0.013) and nocturnal diuresis (p=0.013). Improvement was observed in PSQI perceived sleep quality (p=0.018) and actigraphy derived sleep efficiency (p=0.002). NQoL global score also showed significant improvement (p=0.037).No change was observed in autonomic dysfunction measurements. Conclusion With appropriate treatment of SDB an improvement was observed in nocturia frequency and associated co-morbidities in a sample of relatively healthy individuals. These results suggests that significant nocturia should prompt the assessment for and treatment of SDB.

On the nature of the eye-heart reflex

The eye-heart reflex was investigated by us in sick and healthy people in the amount of over 600 people, compared with orthostatic and clinostatic changes in the pulse, in a number of cases (about 200) replenished with the study of the Chermak reflex and refl. from the solar plexus.

Abstract P204: Sinusoidal Galvanic Stimulation Improves Orthostatic Symptoms In Patients With Postural Tachycardia.

Postural Tachycardia Syndrome (POTS) is characterized by frequent orthostatic symptoms and excessive heart rate increase (>= 30 bpm) on standing in the absence of orthostatic hypotension for more than 6 months. We and others have described a vestibulo-sympathetic reflex that can be engaged by galvanic vestibular stimulation to modulate sympathetic activity (Biaggioni et al., 2000; Kaufmann et al., 2002; Monahan & Ray, 2002; Ray & Carter, 2003, Bent, Macefield et al. 2006). We hypothesize that habituation to sinusoidal galvanic vestibular stimulation will improve orthostatic tolerance. We studied 6 patients with POTS (30.5+/6.0 years, BMI 22.8+/-2.9 kg/m 2 ) in two sessions using sinusoidal galvanic vestibular stimulation (sGVS 0.025 Hz, 2mA) or sham (0.01 mA). Stimulation was applied near mastoid process for 30 min in semi-recumbent position before orthostatic challenge. Patient were upright for a maximum of 15 minutes after each stimulation. Orthostatic change in Vanderbilt Orthostatic Symptom Score (dVOSS), orthostatic heart rate increase (dHR) and blood pressure response were recorded. Non-parametric Wilcoxon test for paired measures with significance level p<0.05 was used. sGVS stimulation reduced overall orthostatic symptom score (dVOSS sham: 32.5+/-9.3 bpm vs dVOSS sGVS: 10.5+/-5.5, p=0.03) and tended to reduce orthostatic HR increase (dHR sham: 65.83+/-11.5 vs dHR sGVS: 46.5+/-10.7 bpm, p=0.06). Blood pressure and tilt time did not change. This pilot study suggests that habituation to sinusoidal vestibular could be used to improve orthostatic symptoms and orthostatic tolerance.

Abstract P196: Exacerbation Of Postural Tachycardia Syndrome After An Oral Glucose Challenge: Role Of Incretins

Postural Tachycardia Syndrome (POTS) is characterized by excessive upright tachycardia and disabling pre-syncopal symptoms, which are exacerbated after consuming a high-carbohydrate meal. The purpose of this study is to investigate the effect of oral glucose on orthostatic hemodynamic changes and gastrointestinal hormone secretion in POTS. We studied 12 women with POTS and 13 age-matched controls, all subjects received 75-gr oral glucose and 20 mg/kg acetaminophen for nutrient absorption measurement. Hemodynamic, GI hormone secretion and acetaminophen levels were measured at different time-points up to 120-min post-ingestion and while supine and standing. POTS patients had significant upright tachycardia ( delta HR: 48.7 ± 11.2 vs. 23.3 ± 8.1 bpm, P=0.012) and norepinephrine levels (835.2 ± 368.4 vs. 356.9 ± 156.7 pg/mL, P= 0.004). After oral glucose, upright HR significantly increased in POTS (92±15.5 vs. 112± 26 bpm, P=0.002) with a concomitant decline in upright stroke volume (P=0.027); total peripheral resistance, blood pressure and cardiac output remained unaltered. Acetaminophen rate of appearance was similar between groups (P=0.707). POTS patients had increased secretion of C-peptide (P=0.001), Glucose Dependent Insulinotropic Peptide (GIP) (P=0.001), peptide YY (P=0.016) and pancreatic polypeptide (P=0.04), but not GLP-1 (p=0.658) or Glucagon (P=0.836). Only GIP had a time-dependent association with the worsening upright tachycardia and SV fall, figure. Conclusions: Oral glucose exacerbated upright tachycardia in POTS, which was associated with a decline in SV; these changes occurred while GIP, a splanchnic vasodilator, is being maximally secreted.

The associations between orthostatic blood pressure changes and extracellular volume in hemodialysis patients.

Extracellular volume (ECV) predicts mortality in hemodialysis patients, but it is difficult to assess clinically. Peridialytic blood pressure (BP) measurements can help ECV assessment. Orthostatic BP is routinely measured clinically, but its association with ECV is unknown. In a cohort of hypertensive hemodialysis patients, we measured posthemodialysis ECV/weight with bioimpedance spectroscopy and analyzed its association with post-HD orthostatic BP measurements obtained during routine care. Using linear and logistic regression, the primary outcomes were orthostatic BP change and orthostatic hypotension (OH) defined by systolic BP decrease of at least 20 mmHg or diastolic decrease of at least 10 mmHg. Model 1 controlled for sex, age, and diabetes. Model 2 additionally controlled for ultrafiltration rate and antihypertensive medications. We conducted sensitivity analysis using OH definition of systolic BP decrease of at least 30 mmHg. Among 57 participants, mean orthostatic systolic BP change was -7.30 (20) mmHg and mean ECV/weight was 0.24 (0.04) L/kg. Post-HD ECV/weight was not associated with orthostatic systolic BP change (β=8.2, p=0.6). There were 16 participants with and 41 participants without OH. The ECV/weight did not differ between these groups (0.22 [0.04] vs. 0.24 [0.05] L/Kg, p=0.09) and did not predict OH in logistic regression (OR 11, 4.04; 95% CI 0.2-671, 0.03-0.530 in the two models.) In a sensitivity analysis, ECV/weight was lower in the OH group (0.22 [0.03] vs. 0.25 [0.04] L/kg, p=0.005), but this was accompanied by differences in sex and diabetes. Using logistic regression, there was no independent association between ECV/weight with OH. Orthostatic systolic BP change after HD completion is not a reliable indicator of posthemodialysis ECV. When considering other factors associated with orthostatic BP, ECV/weight is not independently associated with OH. Although transient postdialytic differences in intravascular volume may be associated with OH, posthemodialysis OH does not necessarily indicate ECV depletion.

Cardiac sympathetic burden reflects Parkinson disease burden, regardless of high or low orthostatic blood pressure changes

Reduced uptake of 123I-meta-iodobenzylguanidine (123I-MIBG) and orthostatic hypotension (OH) are independently associated with worse clinical outcomes of Parkinson’s disease (PD). However, their interactive influence on PD has not been studied. The role of 123I-MIBG myocardial uptake, as a biomarker of PD severity, was investigated, conditional on the mediating effects of OH. A total of 227 PD patients were enrolled. Their motor and nonmotor aspects were assessed with standardized tools. Global disease burden was estimated by averaging the scaled z-scores of the assessment tools. Every patient went through 123I-MIBG scan, and OH was evaluated with the head-up tilt-test. The mediating role of orthostatic blood pressure changes (ΔBP) on the association between cardiac sympathetic denervation and disease burden was investigated. Low heart-to-mediastinum (H/M) ratio with less than 1.78 was seen in 69.6% of the patient population, and 22.9% of patients had OH. Low H/M ratio was associated with OH, and these patients had worse disease burden than subjects with normal 123I-MIBG uptake (global composite z-score: normal 123I-MIBG vs. abnormal 123I-MIBG; −0.3 ± 0.5 vs. 0.1 ± 0.7; p < 0.001). The mediation models, controlled for age and disease duration, revealed that the delayed H/M ratio and global composite score were negatively associated, irrespective of orthostatic ΔBP. Adverse relationship between cardiac sympathetic denervation and disease burden was shown without any interference from orthostatic blood pressure fluctuations. This result suggested that extracranial cardiac markers might reflect disease burden, regardless of labile blood pressure influence.

Comparison of Brachial Blood Pressure and Central Blood Pressure in Attended, Unattended, and Unattended Standing Situations.

Central systolic blood pressure (cSBP) is an independent predictor of future cardiovascular disease. Unattended brachial SBP (bSBP) can eliminate the white-coat effect. However, unattended cSBP and unattended standing cSBP have never been reported. We aimed to compare bSBP and cSBP in attended, unattended, and unattended standing situations. We also aimed to compare the white-coat effect and unattended orthostatic BP change between bSBP and cSBP. Altogether, 104 hypertensive outpatients were included (mean age: 66.0 ± 9.8 years, 41.3% male, mean body mass index: 25.0 ± 4.5). Attended bSBP/cSBP values were 127.3 ± 15.7/119.2 ± 15.0, unattended bSBP/cSBP values were 122.7 ± 15.3/114.4 ± 15.1, and unattended standing bSBP/cSBP values were 123.6 ± 15.7/114.1 ± 14.8 mmHg (correlation coefficients/coefficients of determination between bSBP and cSBP: 0.971/0.943, 0.970/0.941, and 0.964/0.929, respectively; all p < 0.001). No significant difference was observed in the white-coat effect between bSBP and cSBP (4.6 ± 5.8 vs. 4.8 ± 5.7 mmHg). Although there was no significant difference between unattended sitting SBP and unattended standing SBP in terms of both bSBP and cSBP, a numerically small but significant difference was observed in the unattended orthostatic BP change between bSBP and cSBP (0.9 ± 8.0 vs. -0.3 ± 9.0 mmHg, p = 0.002). In conclusion, significant and strong correlations were observed between bSBP and cSBP in attended, unattended, and unattended standing BP measurements. The white-coat effect on bSBP was equivalent to that on cSBP. There was a numerically small but significant difference in the unattended orthostatic BP change between bSBP and cSBP.

Clinical Epidemiology of Systolic and Diastolic Orthostatic Hypotension in Patients on Peritoneal Dialysis.

Blood pressure changes upon standing reflect a hemodynamic response, which depends on the baroreflex system and euvolemia. Dysautonomia and fluctuations in blood volume are hallmarks in kidney failure requiring replacement therapy. Orthostatic hypotension has been associated with mortality in hemodialysis patients, but neither this relationship nor the impact of changes in blood pressure has been tested in patients on peritoneal dialysis. We investigated both these relationships in a cohort of 137 PD patients. The response to orthostasis was assessed according to a standardized protocol. Twenty-five patients (18%) had systolic orthostatic hypotension, and 17 patients (12%) had diastolic hypotension. The magnitude of systolic and diastolic BP changes was inversely related to the value of the corresponding supine BP component (r = −0.16, p = 0.056 (systolic) and r = −0.25, p = 0.003 (diastolic), respectively). Orthostatic changes in diastolic, but not in systolic, BP were linearly related to the death risk (HR (1 mmHg reduction): 1.04, 95% CI 1.01–1.07, p = 0.006), and this was also true for CV death (HR: 1.08, 95% CI 1.03–1.12, p = 0.001). The strength of this association was not affected by further data adjustment (p ≤ 0.05). These findings suggest that independent of the formal diagnosis of orthostatic hypotension, even minor orthostatic reductions in diastolic BP bear an excess death risk in this population.

Preclinical predictors of arterial hypertension

Arterial hypertension (AH) remains one of the most common diseases and a leading risk factor for cardiovascular diseases (CVD) in the 21st century. It determines the importance of a search for new factors provoking an increase in blood pressure. This review focuses on studies of preclinical predictors of hypertension. Orthostatic circulatory disorders with clinical signs of cardiovascular deconditioning are risk factors for the development of hypertension and CVD, accompanied by a more rapid increase in vascular stiff ness. Such abnormalities, even minor ones without clinical manifestations, increase the risk of hypertension development in the young population. The review deals with orthostatic changes in hemodynamics and features of neurohormonal change. It has been shown that adaptive processes counteracting an increase in hydrostatic pressure contribute to a significant transient increase in vascular stiff ness. The evolution of orthostatic hemodynamic disorders from preclinical to clinical forms accelerates the process of vascular wall remodeling, leading to a spontaneous increase in its rigidity — one of the significant risk factors for hypertension and CVD. To identify preclinical predictors, a new protocol of passive orthostatic test (POT) was developed. It was standardized not by the tilt angle, but by the height of the hydrostatic column. Further research is needed to evaluate the prognostic capabilities of predictors, to reveal the pathogenetic connection of orthostatic disorders with the development of hypertension, and to remodeling the vascular wall, which causes an increase in its rigidity. It is also required to search for ways to correct preclinical orthostatic disorders in healthy young population for early prevention of hypertension.

Implications of Circadian Rhythm in Stroke Occurrence: Certainties and Possibilities.

Stroke occurrence is not randomly distributed over time but has circadian rhythmicity with the highest frequency of onset in the morning hours. This specific temporal pattern is valid for all subtypes of cerebral infarction and intracerebral hemorrhage. It also correlates with the circadian variation of some exogenous factors such as orthostatic changes, physical activity, sleep-awake cycle, as well as with endogenous factors including dipping patterns of blood pressure, or morning prothrombotic and hypofibrinolytic states with underlying cyclic changes in the autonomous system and humoral activity. Since the internal clock is responsible for these circadian biological changes, its disruption may increase the risk of stroke occurrence and influence neuronal susceptibility to injury and neurorehabilitation. This review aims to summarize the literature data on the circadian variation of cerebrovascular events according to physiological, cellular, and molecular circadian changes, to survey the available information on the chronotherapy and chronoprophylaxis of stroke and its risk factors, as well as to discuss the less reviewed impact of the circadian rhythm in stroke onset on patient outcome and functional status after stroke.

Quantitative sensory testing and norepinephrine levels in REM sleep behaviour disorder – a clue to early peripheral autonomic and sensory dysfunction?

IntroductionStudies have reported autonomic impairment in patients with idiopathic REM sleep behaviour disorder (iRBD), which is considered a prodromal stage of alpha-synucleinopathies. It is still debated whether central or peripheral pathologies are first manifestations of alpha-synucleinopathies. This study aimed to characterize autonomic and somatosensory function in iRBD patients.MethodsThis cross-sectional prospective case–control study included 17 iRBD patients (mean age 66.3 ± 9.2 years) and 16 healthy controls (HCs, 66.6 ± 11.3 years). Quantitative sensory testing, neurological and neuropsychological assessments, norepinephrine blood plasma levels, tilt table examination with orthostatic blood pressure, and heart rate variability were carried out. Longitudinal data of 10 iRBD patients, including neurological, neuropsychological, and tilt table examination, were assessed.ResultsiRBD patients more frequently presented with orthostatic dysfunction than HCs (70.6% vs. 6.3%, p < 0.0001). Supine norepinephrine plasma levels were normal, but lower in iRBD (249.59 ± 99.78 pg/ml iRBD, 354.13 ± 116.38 pg/ml HCs, p < 0.05). Quantitative sensory testing revealed impaired cold (CDT) and vibration detection thresholds (VDT) on the foot in iRBD (CDT foot iRBD − 1.24 ± 0.31, HCs − 9.89E-17 ± 0.25, VDT iRBD − 1.11 ± 0.47, HCs − 1.46E-16 ± 0.25, p < 0.05). Cold detection thresholds differed between the foot and hand among iRBD patients (foot − 1.24 ± 0.31, hand − 0.56 ± 0.25, p < 0.05). Longitudinal data revealed an increase in maximum systolic and diastolic orthostatic blood pressure changes and a decrease in the Valsalva ratio in the follow-up group (p < 0.05).ConclusionThis study revealed autonomic dysfunction with somatosensory impairment, and decreased norepinephrine levels in iRBD, which may serve as a possible prodromal marker for developing alpha-synucleinopathy.

Quantitative Assessment of the Incidence of Persistent Orthostatic Hemodynamic Changes After Celiac Plexus Neurolysis: A Prospective Case Series.

Celiac plexus neurolysis has been associated with orthostatic hypotension but has not been quantified prospectively or evaluated for persistence after the immediate postprocedural period. Our objective was to quantify persistent hemodynamic changes induced by celiac plexus neurolysis. In this case series of 16 patients with cancer, 8 (50%) had orthostatic hypotension alone, 3 (18.75%) developed an exaggerated postural heart rate increase (>30 beats per min), and 1 (6.25%) had both orthostatic hypotension and an increased heart rate. While the analgesic benefit of celiac plexus neurolysis is clear, the observed hemodynamic changes may be poorly tolerated in some individuals.

Excessive Orthostatic Changes in Blood Pressure Are Associated With Incident Heart Failure in Older Men: A Prospective Analysis From the BRHS.

[Figure: see text].

Delayed orthostatic hypotension in Parkinson\u2019s disease

Orthostatic hypotension (OH) is relatively common in the early stage of Parkinson’s disease (PD). It is divided into delayed OH and classical OH. Classical OH in PD has been investigated widely, however, the clinical implications of delayed OH in PD have seldom been studied. The purpose of this study is to characterize delayed OH in PD. A total of 285 patients with early drug-naïve PD were enrolled and divided into three groups according to orthostatic change: no-OH, delayed OH, and classical OH. The disease severity in terms of motor, non-motor, and cognitive functions was assessed. The cortical thickness of 82 patients was analyzed with brain magnetic resonance imaging. The differences among groups and linear tendency in the order of no-OH, delayed OH, and classical OH were investigated. Seventy-seven patients were re-evaluated. Initial and follow-up evaluations were explored to discern any temporal effects of orthostasis on disease severity. Sixty-four (22.5%) patients were defined as having delayed OH and 117 (41.1%) had classical OH. Between-group comparisons revealed that classical OH had the worst outcomes in motor, non-motor, cognitive, and cortical thickness, compared to the other groups. No-OH and delayed OH did not differ significantly. Linear trends across the pre-ordered OH subtypes found that clinical parameters worsened along with the orthostatic challenge. Clinical scales deteriorated and the linear gradient was maintained during the follow-up period. This study suggests that delayed OH is a mild form of classical OH in PD. PD with delayed OH has milder disease severity and progression.

ARTERIAL STIFFNESS AND ORTHOSTATIC BLOOD PRESSURE CHANGES IN HYPERTENSIVE ADULTS – RESULTS FROM SEPHAR III SURVEY

Objective: To evaluate the relationship between orthostatic hypotension (OH) and arterial stiffness in controlled and uncontrolled hypertensive adults Design and method: Eight hundred eighty-nine hypertensive subjects identified in SEPHAR III national-representative survey (aged 18 to 80 years; mean age 48.5 ± 17.5 years, 52.5%females, 81,3% treated, 30,8% controlled) were studied. BP in both sitting and at 1 and 3 minutes after standing up was measured. Arterial stiffness was assessed by PWVao measured by a sphygmomanometric method (Arteriograph). Orthostatic hypotension (OH) was defined by SBP decrease of at least 20mmHg and/or DBP decrease of at least 10mmHg at 3 minutes after standing. Results: Orthostatic Hypotension was identified in 161 subjects, representing 19% of the sample., with significantly higher prevalence among uncontrolled hypertensive subjects (21,3% vs. 10.9%, p = 0,001) In uncontrolled hypertensive subjects, the orthostatic alterations in systolic, but not in diastolic blood pressure (DBP), were inversely related to PWV, independently from age, gender, mean BP, and diabetes mellitus. In uncontrolled hypertensive subjects the greater the aortic stiffness the larger was the systolic blood pressure (SBP) decrease after assuming orthostatic position. On the contrary, no such association was found between PWV and orthostatic changes of BP in controlled hypertensive subjects. Conclusions: Our results suggest the presence of a pathophysiological association between arterial stiffening and BP postural changes in hypertensive adults. Antihypertensive drug treatment, as well as other factors that have not been evaluated in the present study, might have modulated this association.

ORTHOSTATIC BLOOD PRESSURE CHANGES AND SUBCLINICAL MARKERS OF ATHEROSCLEROSIS IN NORMOTENSIVE ADULTS. RESULTS FROM A NATIONAL-REPRESENTATIVE SURVEY

Objective: To evaluate the relationship between orthostatic upright postural blood pressure (BP) changes and subclinical markers of atherosclerosis in normotensive subjects using a simple 3-minutes standing up test. Design and method: A total of 1081 normotensive subjects enrolled in SEPHAR III national-representative survey, aged 18–80 years (42,4 ± 16.7 years, 55,3% females) underwent a simple 3 standing-up test involving BP measurement in supine position followed by BP measurements at 1 minute and 3 minutes after standing. We measured: aortic pulse wave velocity (PWVao) using a sfigmomanometric method (Arteriograph), body mass index (BMI), serum lipids, glyceated hemoglobin (HbA1c), urinary albumin-to-creatinine ratio (UACR) in morning spot urine and mean carotid intima-media thickness (IMT) by B-mode Doppler ultrasound. Orthostatic hypotension (OH) was defined by SBP decrease of at least 20mmHg and/or DBP decrease of at least 10mmHg, at 3 minutes after standing. Results: SBP and DBP increased when standing, with an average increase of SBP/DBP values when changing position of 3.7 ± 19.5 mm Hg / 9.6 ± 13.5 mm Hg at 1 minutes and 2.9 ± 19.2 mm Hg / 10.1 ± 13.2 mm Hg. Orthostatic hypotension (OH) was recoded in 130 subjects representing 12,4% of the study sample. The PWVao was significantly higher in OH subjects than in those without OH (9,12 ± 2.13m/s vs 8.08 ± 1.86m/s, p = 0,032). Stepwise regression analysis adjusted for age, sex, BMI, baseline SBP, triglycerides, HDL- cholesterol, LDL- cholesterol, fasting glucose, HbA1c, IMT, UACR and PWVao confirmed that PWVao, LDL-cholesterol and TG were independently related to orthostatic BP changes. Multiple regression analyses showed that age, baseline SBP, decrease in SBP at 3-minutes, BMI and fasting glucose were independent determinants of PWVao. Conclusions: Our results have shown that increased arterial stiffness is associated with OH during a 3- minutes standing-up test. Also, arterial stiffness may contribute to greater BP responses to postural changes from standing in normotensive subjects.

Effects of an Innovative Head-Up Tilt Protocol on Blood Pressure and Arterial Stiffness Changes.

The objective of our study was to identify blood pressure (BP) and pulse wave velocity (PWV) changes during orthostatic loading, using a new the head-up tilt test (HUTT), which incorporates the usage of a standardized hydrostatic column height. Methods: 40 healthy subjects 20–32 years performed HUTT, which was standardized to a height of the hydrostatic column at 133 cm. Exposure time was 10 min in each of 3 positions: horizontal supine 1, HUTT, and horizontal supine 2. The individual tilt up angle made it possible to set the standard value of the hydrostatic column. Hemodynamic parameters were recorded beat to beat using “Task Force Monitor 3040 i”, pulse-wave velocity (PWV) was measured with a sphygmograph–sphygmomanometer VaSera VS1500N. Results: Orthostatic loading caused a significant increase in heart rate (HR) and a decrease in stroke volume (SV) (p < 0.05) but no significant reductions in cardiac output, changes in total vascular resistance (TVR), or BP. An analysis of personalized data on systolic blood pressure (SBP) changes in tilt up position as compared to horizontal position (ΔSBP) revealed non-significant changes in this index in 48% of subjects (orthostatic normotension group), in 32% there was a significant decrease in it (orthostatic hypotension group) and in 20% there was a significant increase in it (orthostatic hypertension group). These orthostatic changes were not accompanied by any clinical symptoms and/or syncope. During HUTT, all subjects had in the PWV a significant increase of approximately 27% (p < 0.001). Conclusion: The new test protocol involving HUTT standardized to a height of hydrostatic column at 133 cm causes typical hemodynamics responses during orthostatic loading. Individual analysis of the subjects revealed subclinical orthostatic disorders (OSD) in up to 52% of the test persons. During HUTT, all test subjects showed a significant increase in PWV. The new innovative HUTT protocol can be applied in multi-center studies in healthy subjects to detect preclinical forms of orthostatic disorders under standard gravity load conditions.

Orthostatic Hypertension and Hypotension and Outcomes in CKD: The CRIC (Chronic Renal Insufficiency Cohort) Study

Rationale & ObjectiveThere are limited data about the prevalence and prognostic significance of orthostatic hypo- and hypertension in patients with chronic kidney disease. The objective of this study is to determine the prevalence of orthostatic hypo- and hypertension in a cohort of patients with chronic kidney disease and examine their association with clinical outcomes.Study DesignProspective cohort study: Chronic Renal Insufficiency Cohort (CRIC) Study.Setting & Population7 clinical centers, participants with chronic kidney disease.ExposuresOrthostatic hypotension (decline in systolic blood pressure [BP] > 20 mm Hg) and orthostatic hypertension (increase in systolic BP > 20 mm Hg) from seated to standing position.OutcomesCardiovascular and kidney outcomes and mortality.Analytical ApproachLogistic regression was used to determine factors associated with orthostatic hypo- and hypertension; Cox regression was used to examine associations with clinical outcomes.ResultsMean age of study population (n = 3,873) was 58.1 ± 11.0 years. There was a wide distribution of change in systolic BP from seated to standing (from −73.3 to +60.0 mm Hg); 180 participants (4.6%) had orthostatic hypotension and 81 (2.1%) had orthostatic hypertension. Diabetes, reduced body mass index, and β-blocker use were independently associated with orthostatic hypotension. Black race and higher body mass index were independently associated with orthostatic hypertension. After a median follow-up of 7.9 years, orthostatic hypotension was independently associated with high risk for cardiovascular (HR, 1.12; 95% CI, 1.03-1.21) but not kidney outcomes or mortality. Orthostatic hypertension was independently associated with high risk for kidney (HR, 1.51; 96% CI, 1.14-1.97) but not cardiovascular outcomes or mortality.LimitationsOrthostatic change in BP was ascertained at a single visit.ConclusionsOrthostatic hypotension was independently associated with higher risk for cardiovascular outcomes, whereas orthostatic hypertension was associated with higher risk for kidney outcomes. These findings highlight the importance of orthostatic BP measurement in practice and the need for future investigation to understand the mechanisms and potential interventions to minimize the risk associated with orthostatic changes in BP.

Increased pulse wave velocity in patients with an orthostatic blood pressure rise independent of other cardiovascular risk factors.

Positional changes in blood pressure (BP) have been shown to have effects on long-term outcomes. Although a BP drop with upright posture is frequently observed, an orthostatic rise in BP can also occur. Here, we aimed to investigate whether the phenotype of orthostatic hypertension is associated with more pronounced vascular hypertension-mediated organ damage (HMOD) and whether this is associated with other cardiovascular risk factors. In a cohort of 200 patients referred to our tertiary hypertension clinic, we prospectively assessed unattended seated automated office BP and the response to 1 min of upright posture. The difference in BP after standing up was calculated and pulse wave velocity (PWV) was assessed as a marker of vascular HMOD. Routine clinical cardiovascular risk markers were also assessed. Regression models were used to assess the association between orthostatic BP changes and pulse wave velocity. Baseline characteristics and clinic cardiovascular risk factors were similar between orthostatic BP response groups. A U-shaped association was evident between PWV and orthostatic BP changes with elevated PWV in patients with either a fall or a rise in BP in response to upright posture. The regression models remained significant after adjusting for other cardiovascular risk factors, including 24 h ambulatory BP. Both an orthostatic BP drop and rise were associated with elevated PWV. Although standing BP is commonly measured in elderly hypertensive patients to exclude significant orthostatic hypotension, this simple measurement may provide an additional independent risk factor for vascular HMOD at any age.