Orthostatic blood pressure adaptations, aortic stiffness, and central hemodynamics in the general population: insights from the Malmö Offspring Study (MOS)

The relationship between physical activity, orthostatic blood pressure reactions and subclinical atherosclerosis: the Swedish CArdioPulmonary bioImage Study (SCAPIS)

An abnormal blood pressure (BP) response on standing is associated with atherosclerotic cardiovascular disease (CVD). The role of physical activity (PA) on orthostatic BP-reactions and its relation to subclinical atherosclerosis is unclear. We aimed to assess the association between PA and orthostatic BP-reactions, and whether PA modifies the relationship between orthostatic BP-reactions and subclinical atherosclerosis. A total of 5,396 middle aged subjects from the population-based SCAPIS-study were included. Associations between orthostatic BP-response and accelerometer-derived PA were studied using linear regression. Interaction analyses were performed to study modifying effects of PA on the relationship between orthostatic BP-response and subclinical coronary atherosclerosis, assessed by coronary artery calcium score (CACS). Moderate to vigorous PA (MVPA) was associated with less pronounced orthostatic systolic BP (SBP) increase but more pronounced orthostatic diastolic BP increase after adjusting for age, sex, total wear time, proportion weekend days and season (Beta per 1%-increase(mmHg):0.12; p = <0.01 and -0.06; p = 0.02, respectively). Subjects with high MVPA were less likely to have orthostatic hypertension (OHTN), but more likely to have orthostatic hypotension (OH; p = 0.002 for both). Individuals with higher CACS were more likely to have OH (p = 0.041) but not OHTN (p = 0.276). There were no interactions of PA on the association between orthostatic BP-response and CACS. In conclusion, physically active middle-aged individuals are less likely to show inappropriate SBP-increase upon standing, but more likely to have excessive SBP-decrease. PA does not modify the association between orthostatic BP-response and subclinical atherosclerosis. The relationship between PA, orthostatic BP and CVD is likely to be complex.

Effects of intensive blood pressure treatment on orthostatic hypertension: individual level meta-analysis

OBJECTIVE

To determine the effects of intensive blood pressure treatment on orthostatic hypertension.

DESIGN

Systematic review and individual participant data meta-analysis.

DATA SOURCES

MEDLINE, Embase, and Cochrane CENTRAL databases through 13 November 2023.

INCLUSION CRITERIA

Population: ≥500 adults, age ≥18 years with hypertension or elevated blood pressure; intervention: randomized trials of more intensive antihypertensive drug treatment (lower blood pressure goal or active agent) with duration ≥6 months; control: less intensive antihypertensive drug treatment (higher blood pressure goal or placebo); outcome: measured standing blood pressure.

MAIN OUTCOMES

Orthostatic hypertension, defined as an increase in systolic blood pressure ≥20 mm Hg or diastolic blood pressure ≥10 mm Hg after changing from sitting to standing.

DATA SYNTHESIS

Two investigators independently abstracted articles. Individual participant data from nine trials identified during the systematic review were appended together as a single dataset.

RESULTS

Of 31 124 participants with 315 497 standing blood pressure assessments, 9% had orthostatic hypotension (that is, a drop in blood pressure after standing of systolic ≥20 mm Hg or diastolic ≥10 mm Hg), 17% had orthostatic hypertension, and 3.2% had both a rise in systolic blood pressure and standing blood pressure ≥140 mm Hg at baseline. The effects of more intensive treatment were similar across trials with odds ratios for orthostatic hypertension ranging from 0.85 to 1.08 (I2=38.0%). During follow-up, 17% of patients assigned to more intensive treatment had orthostatic hypertension, whereas 19% of those assigned less intensive treatment had orthostatic hypertension. Compared with less intensive treatment, the risk of orthostatic hypertension was lower with more intensive blood pressure treatment (odds ratio 0.93, 95% confidence interval 0.90 to 0.96). Effects were greater among non-black versus black adults (odds ratio 0.86 v 0.97; P for interaction=0.003) and adults without diabetes versus those with diabetes (0.88 v 0.96; P for interaction=0.05) but did not differ by age ≥75 years, sex, baseline seated blood pressure ≥130/≥80 mm Hg, obesity, stage 3 kidney disease, stroke, cardiovascular disease, standing systolic blood pressure ≥140 mm Hg, or pre-randomization orthostatic hypertension (P for interactions ≥0.05).

CONCLUSIONS

In this pooled cohort of adults with elevated blood pressure or hypertension, orthostatic hypertension was common and more intensive blood pressure treatment modestly reduced the occurrence of orthostatic hypertension. These findings suggest that approaches generally used for seated hypertension may also prevent hypertension on standing.

STUDY REGISTRATION

Prospero CRD42020153753 (original proposal).

Gender Difference in Orthostatic Vascular Stiffness Increase in Young Subjects

Background/Objectives: Early detection of increased vascular stiffness in young populations may facilitate the development of more effective strategies for the primary prevention of arterial hypertension and other age-related cardiovascular diseases. To examine gender differences in orthostatic increases in vascular stiffness during the head-up tilt test (HUTT), standardized by hydrostatic column height. Materials and Methods: A total of 133 healthy adults aged 18-20 years (93 females and 40 males) were evaluated. Blood pressure and pulse wave velocity at the brachial-ankle artery site (baPWV) were measured using an ABI system 100 PWV multichannel sphygmomanometer. Orthostatic changes in arterial stiffness were assessed during a head-up tilt test (HUTT) using the Luanda protocol, which standardizes hydrostatic column height. The functional reserve coefficient (FRC) of orthostatic circulatory regulation was introduced as a measure of adaptive capacity: FRC = ΔbaPWV/baPWVb. This coefficient accounts for both structural (baPWVb) and functional (ΔbaPWV = baPWVt - baPWVb) components influencing cardiovascular system adaptation, which exhibit multidirectional changes with age. Results: Baseline baPWV (baPWVb) values in the horizontal position showed no significant differences between genders and were within normal age ranges. However, baPWV values in the upright HUTT position (baPWVt) were significantly higher in men (p = 0.0007). Dynamic biomarkers of vascular reserve, including ΔbaPWV and FRC, were also significantly elevated in men (p = 0.0009 and p = 0.0064, respectively). Conclusions: While baseline baPWVb values were comparable between genders, dynamic biomarkers of vascular reserve, such as ΔbaPWV and FRC, were significantly higher in men. Prospective studies are needed to establish optimal reference values for these dynamic biomarkers, enabling the assessment of individual trends in vascular aging and evaluating the effects of treatment, lifestyle modifications, and other preventive measures on vascular health.

Blood Pressure Regulation in Post-COVID POTS: Beyond Sinus Tachycardia

BACKGROUND

Postural orthostatic tachycardia syndrome (POTS) is a frequently diagnosed cardiovascular disorder after COVID-19 infection. POTS is characterized by the presence of excessive sinus tachycardia on standing without a fall in blood pressure (BP). We investigated the BP profile using 24-hour ambulatory BP monitoring in patients with new-onset POTS after COVID-19 compared with prepandemic population-based controls.

METHODS

We performed a case-control study in 100 patients (mean age, 40.0±12.9 years; 85% women) with verified post-COVID-19 new-onset POTS diagnosed by a positive head-up tilt testing versus 100 controls from a population-based cohort with a negative active standing test, no history of syncope, POTS, or endocrine disease (mean age, 42.3±14.0 years; 78% women). Twenty-four-hour BP profile was assessed for circadian BP variation including hypotensive systolic BP (SBP) episodes (<80, <90, and <100 mm Hg).

RESULTS

Patients with post-COVID-19 POTS had significantly higher nighttime SBP, but not daytime SBP, and more daytime SBP hypotensive episodes compared with controls. Nondipping (34% versus 19%; P<0.001) and reverse dipping patterns (9% versus 0%; P<0.001) were more frequent in post-COVID-19 POTS. In the logistic regression, patients with post-COVID-19 POTS had significantly higher mean 24-hour SBP (odds ratio, 1.08 [95% CI, 1.04-1.11]; P<0.001) and nighttime SBP (odds ratio, 1.07 [95% CI, 1.04-1.10]; P<0.001), independent of age and sex.

CONCLUSIONS

Patients with post-COVID-19 POTS demonstrate higher mean 24-hour and nighttime SBP and show disruptions of circadian BP rhythm regulation compared with population-based controls, as well as more daytime hypotensive episodes. Future studies are needed to test whether patients with post-COVID-19 POTS may benefit from tailored BP therapy.

Vascular ageing in relation to chronological and self-perceived age in the general Swedish population

Background. Aortic stiffness is a marker of vascular ageing. Non-conventional risk markers reflecting vascular ageing are largely unexplored. We aimed to investigate the relationship between self-perceived age (SPA) and self-rated health (SRH) with aortic stiffness in the general population. Methods. Cross-sectional assessment of 3760 participants from two Swedish population-based cohorts (mean age 43.5 ± 14.5 years, 53.4% women). Participants completed two self-administered questions about SPA (SPA-self referring to SPA perceived by oneself, and SPA-others referring to SPA perceived by others) graded as: younger, no difference, or older than same-aged/sex peers. SRH was graded as poor versus good. Aortic stiffness (vascular ageing) was assessed by carotid-femoral pulse wave velocity (PWV). Linear regression was performed stratified by the median age of 45 years. Results. Chronologically younger men and women ≤45 years with older SPA-others had unexpectedly lower PWV (β - 0.39, p < .001 and β - 0.40, p < .001, respectively), independently of cardiovascular risk factors and social health determinants, compared with subjects with younger SPA-others. Lower PWV was also observed in women ≤45 years with older SPA-self (β - 0.24 m/s, p = .005) compared with younger SPA-self, but not in men. A similar pattern between SPA-self, SPA-others and PWV was found in chronologically younger subjects ≤45 years reporting good SRH. On the contrary, chronologically older subjects >45 years reporting poor SRH, with older SPA-others had increased vascular ageing (PWV β 2.57, p = .03). Conclusions. Self-perceived age is a subjective cognitive variable inversely associated with vascular ageing particularly among chronologically younger adults ≤45 years.

The Importance of Orthostatic Increase in Pulse Wave Velocity in the Diagnosis of Early Vascular Aging

Background/Objectives: Vascular aging can be assessed by arterial stiffness measured through pulse wave velocity (PWV). Increased PWV predicts arterial hypertension, cardiovascular events and all-cause mortality. Detection of early signs of vascular aging remains an unmet problem. To search for the most sensitive markers for the early increase in vascular stiffness in a healthy population. Methods: One-hundred and twenty healthy subjects were divided in three equal age groups: <30 years, 30-45 years and >45 years. Head-up tilt test (HUTT) protocol was applied, providing a standardized hydrostatic column height. PWV at the brachial-ankle artery site (baPWV) was measured using a multichannel sphygmomanometer ABI System 100 PWV in three positions: in the baseline horizontal (supine) position-baPWVb; during the head tilt-up with an individual angle of inclination-baPWVt; and when returning to supine. Results: The most sensitive marker of early stiffness increase in a healthy population is the relative orthostatic increase in baPWV, ΔbaPWV/baPWVb, where ΔbaPWV = baPWVt - baPWVb. The significance of differences in this parameter between the young and elderly groups reached p = 0.000075 and p = 0.000006, respectively. Conclusions: The proposed index ΔbaPWV/baPWVb can be considered as a promising sensitive early biomarker of vascular aging and as a potential effective indicator in cardiovascular prevention. A longitudinal cohort study is needed to confirm this assumption.

The impact of nursing sustainable prevention program on heat strain among agricultural elderly workers in the context of climate change

BACKGROUND

This study assesses a geriatric nursing-led sustainable heat prevention program for elderly agricultural workers. It targets those aged 60 and above, addressing the heightened risk of heat strain in the era of climate change.

METHODS

A community-based quasi-experimental design involved 120 elderly agricultural workers, divided into intervention and control groups. The program, spanning three months, included education on hydration, rest, protective clothing, and recognition of heat-related illnesses.

RESULTS

The intervention led by geriatric nursing professionals showed significant improvements in heat strain metrics. The Heat Strain Score Index (HSSI) and the Observational-Perceptual Heat Strain Risk Assessment (OPHSRA) Index indicated increased safety levels and reduced risk categories among participants.

CONCLUSIONS

The study demonstrates the effectiveness of a geriatric nursing-led, tailored prevention program in reducing heat strain among elderly agricultural workers. It highlights the crucial role of nursing in adapting healthcare practices to the challenges posed by climate change.

TRIAL REGISTRATION

ClinicalTrials.gov, ID NCT06192069 retrospectively registered.

Assessment and management of exaggerated blood pressure response to standing and orthostatic hypertension: consensus statement by the European Society of Hypertension Working Group on Blood Pressure Monitoring and Cardiovascular Variability

Recent evidence suggests that an exaggerated blood pressure (BP) response to standing (ERTS) is associated with an increased risk of adverse outcomes, both in young and old individuals. In addition, ERTS has been shown to be an independent predictor of masked hypertension. In the vast majority of studies reporting on the prognostic value of orthostatic hypertension (OHT), the definition was based only on systolic office BP measurements. This consensus statement provides recommendations on the assessment and management of individuals with ERTS and/or OHT. ERTS is defined as an orthostatic increase in SBP at least 20 mmHg and OHT as an ERTS with standing SBP at least 140 mmHg. This statement recommends a standardized methodology to assess ERTS, by considering body and arm position, and the number and timing of BP measurements. ERTS/OHT should be confirmed in a second visit, to account for its limited reproducibility. The second assessment should evaluate BP changes from the supine to the standing posture. Ambulatory BP monitoring is recommended in most individuals with ERTS/OHT, especially if they have high-normal seated office BP. Implementation of lifestyle changes and close follow-up are recommended in individuals with ERTS/OHT and normotensive seated office BP. Whether antihypertensive treatment should be administered in the latter is unknown. Hypertensive patients with ERTS/OHT should be managed as any other hypertensive patient. Standardized standing BP measurement should be implemented in future epidemiological and interventional studies.

Plasma Metabolome Predicts Aortic Stiffness and Future Risk of Coronary Artery Disease and Mortality After 23 Years of Follow-Up in the General Population

BACKGROUND

Increased aortic stiffness (arteriosclerosis) is associated with early vascular aging independent of age and sex. The underlying mechanisms of early vascular aging remain largely unexplored in the general population. We aimed to investigate the plasma metabolomic profile in aortic stiffness (vascular aging) and associated risk of incident cardiovascular disease and mortality.

METHODS AND RESULTS

We included 6865 individuals from 2 Swedish population-based cohorts. Untargeted plasma metabolomics was performed by liquid-chromatography mass spectrometry. Aortic stiffness was assessed directly by carotid-femoral pulse wave velocity (PWV) and indirectly by augmentation index (AIx@75). A least absolute shrinkage and selection operator (LASSO) regression model was created on plasma metabolites in order to predict aortic stiffness. Associations between metabolite-predicted aortic stiffness and risk of new-onset cardiovascular disease, cardiovascular mortality, and all-cause mortality were calculated. Metabolite-predicted aortic stiffness (PWV and AIx@75) was positively associated particularly with acylcarnitines, dimethylguanidino valeric acid, glutamate, and cystine. The plasma metabolome predicted aortic stiffness (PWV and AIx@75) with good accuracy (R2=0.27 and R2=0.39, respectively). Metabolite-predicted aortic stiffness (PWV and AIx@75) was significantly correlated with age, sex, systolic blood pressure, body mass index, and low-density lipoprotein. After 23 years of follow-up, metabolite-predicted aortic stiffness (PWV and AIx@75) was significantly associated with increased risk of new-onset coronary artery disease, cardiovascular mortality, and all-cause mortality.

CONCLUSIONS

Aortic stiffness is associated particularly with altered metabolism of acylcarnitines, cystine, and dimethylguanidino valeric acid. These metabolic disturbances predict increased risk of new-onset coronary artery disease, cardiovascular mortality, and all-cause mortality after more than 23 years of follow-up in the general population.

Orthostatic hypotension is associated with higher levels of circulating endostatin

Aims

The pathophysiology of orthostatic hypotension (OH), a common clinical condition, associated with adverse outcomes, is incompletely understood. We examined the relationship between OH and circulating endostatin, an endogenous angiogenesis inhibitor with antitumour effects proposed to be involved in blood pressure (BP) regulation.

Methods and results

We compared endostatin levels in 146 patients with OH and 150 controls. A commercial chemiluminescence sandwich immunoassay was used to measure circulating levels of endostatin. Linear and multivariate logistic regressions were conducted to test the association between endostatin and OH. Endostatin levels were significantly higher in OH patients (59 024 ± 2513 pg/mL) vs. controls (44 090 ± 1978pg/mL, P < 0.001). A positive linear correlation existed between endostatin and the magnitude of systolic BP decline upon standing (P < 0.001). Using multivariate analysis, endostatin was associated with OH (adjusted odds ratio per 10% increase of endostatin in the whole study population = 1.264, 95% confidence interval 1.141-1.402), regardless of age, sex, prevalent cancer, and cardiovascular disease, as well as traditional cardiovascular risk factors.

Conclusion

Circulating endostatin is elevated in patients with OH and may serve as a potential clinical marker of increased cardiovascular risk in patients with OH. Our findings call for external validation. Further research is warranted to clarify the underlying pathophysiological mechanisms.

Accumulation of advanced glycation end products in skin and increased vascular ageing in the general population: the Malmö Offspring Study

OBJECTIVES

Advanced glycation end product (AGE) is an established risk marker for diabetic vascular disease, and associated with the degree of diabetes complications, renal failure, and atherosclerosis in middle-aged and older individuals. The relationship between AGEs and aortic stiffness has not been thoroughly examined in the younger general population. We aimed to evaluate the association between AGEs and aortic stiffness in the general population of young and middle-aged adults.

METHODS

We analysed cross-sectionally 2518 participants from a Swedish population-based cohort, the Malmö Offspring Study (mean age 41.8 ± 14.5 years, 52.2%). Advanced glycation end-products (AGEs) were measured by a well validated, noninvasive method using skin autofluorescence with AGE-Reader. Aortic stiffness was assessed by carotid-femoral pulse wave velocity (PWV) and augmentation index (Aix) was calibrated to a standard heart rate of 75 bpm at the arteria radialis using SphygmoCor. Multivariable linear regression was performed stratified by age to analyse the association between skin AGE and aortic stiffness.

RESULTS

Increased levels of AGEs were significantly associated with higher direct measurements of aortic stiffness (vascular ageing) in younger individuals (PWV β 0.55 m/s, P  < 0.001) after adjustment for traditional cardiometabolic risk factors, however, not in older individuals (PWV β 0.23 m/s, P  = 0.10). Indirect vascular ageing was also significantly associated with higher levels of AGEs in both younger (Aix β 7.78, P  < 0.001) and older individuals (Aix β 3.69, P  < 0.001).

CONCLUSION

Higher levels of skin autofluorescence-AGEs are positively associated with increased vascular ageing in younger adults from the general population, independent of cardiometabolic risk factors.

Preclinical Orthostatic Abnormalities May Predict Early Increase in Vascular Stiffness in Different Age Groups: A Pilot Study

Clinical orthostatic hypotension (OH) and hypertension (OHT) are risk factors for arterial hypertension (AH) and cardiovascular diseases (CVD) and are associated with increased vascular stiffness. Preclinical OH and OHT are poorly understood. The main objective was to investigate preclinical orthostatic abnormalities and their association with increased vascular stiffness in different age groups of adults. A specially designed head-up tilt test standardized for hydrostatic column height was used to detect them. Three age groups of clinically healthy subjects were examined. In the group of young adults up to 30 years old, a significant predominance of orthostatic normotension (ONT) and an insignificant number of subjects with preclinical OH and OHT were found. In the age group over 45 years, compared to the group under 30 years, there was a twofold decrease in the proportion of individuals with ONT and a significant increase with preclinical OH and OHT. In all age groups, there was a significant orthostatic increase in vascular stiffness (as measured by the brachial-ankle pulse wave velocity (baPWV), which was recovered to the baseline level when returning to the supine position. Overall, subjects with preclinical OH and OHT had significantly higher baPWV values compared to those with ONT (p = 0.001 and p = 0.002, respectively), with all subjects having vascular stiffness values within normal age-related values.

Orthostatic Hypertension: A Newcomer Among the Hypertension Phenotypes

The prognostic role and the clinical significance of orthostatic hypertension (OHT) remained undefined for long because data were sparse and often inconsistent. In recent years, evidence has been accumulating that OHT is associated with an increased risk of masked and sustained hypertension, hypertension-mediated organ damage, cardiovascular disease, and mortality. Most evidence came from studies in which OHT was defined using systolic blood pressure (BP) whereas the clinical relevance of diastolic OHT is still unclear. Recently, the American Autonomic Society and the Japanese Society of Hypertension defined OHT as an orthostatic systolic BP increase ≥20 mm Hg associated with a systolic BP of at least 140 mm Hg while standing. However, also smaller orthostatic BP increases have shown clinical relevance especially in people ≤45 years of age. A possible limitation of the BP response to standing is poor reproducibility. OHT concordance is better when the between-assessment interval is shorter, when OHT is evaluated using a larger number of BP readings, and if home BP measurement is used. The pathogenetic mechanisms leading to OHT are still controversial and may vary according to age. Excessive neurohumoral activation seems to be the main determinant in younger adults whereas vascular stiffness plays a more important role in older individuals. Conditions associated with higher activity of the sympathetic nervous system and/or baroreflex dysregulation, such as diabetes, essential hypertension, and aging have been found to be often associated with OHT. Measurement of orthostatic BP should be included in routine clinical practice especially in people with high-normal BP.

Utility of standing office blood pressure in detecting hypertension in healthy adults

Current guidelines recommend office blood pressures (BP) be taken in a seated position when screening for hypertension (HTN). Seated BP is known to have limited accuracy in detecting high BP, while the utility of standing BP in diagnosing HTN is unknown. We conducted a cross-sectional study to determine the incremental value of standing BP in diagnosing HTN. Seated, standing, and 24-h ambulatory BPs (ABPM) were obtained in adults without known cardiovascular disease, HTN, or BP medication use. Presence of HTN was defined by the 2017 ACC/AHA and the 2023 ESH HTN guidelines based on ABPM. Area under the receiver-operating-characteristic curve (AUROC) was used to evaluate the diagnostic accuracy of seated and standing BP. Sensitivity and specificity of standing BP was determined using cut-offs derived from Youden's Index, while sensitivity and specificity of seated BP was determined using the cut-off of 130/80 mmHg and by 140/90 mmHg. Among 125 participants (mean age 49 ± 17 years; 62% female; 24% Black), 33.6% of them had HTN. Sensitivity and specificity of seated systolic BP (SBP) was 43% and 92%, respectively. Cut-offs selected by Youden's index for standing SBP/diastolic BP (DBP) were 124/81 mmHg according to the 2017 ACC/AHA HTN guidelines, and 123.5/83.5 mmHg according to the 2023 ESH HTN guidelines. Sensitivity and specificity of standing SBP was 71% and 67%, respectively. The AUROC of standing SBP (0.81 [0.71-0.92]) was significantly higher than seated SBP (0.70 [0.49-0.91]), when HTN was defined as average 24-h SBP ≥ 125 mmHg. Moreover, the addition of standing to seated SBP (0.80 [0.68-0.92]) improved HTN detection when compared to seated SBP. These patterns were consistent for both the 2017 ACC/AHA and the 2023 ESH definitions for HTN. In summary, standing BP, alone or in combination with seated BP, outperformed seated BP alone in diagnosing HTN in adults.

Exaggerated blood pressure response to standing in young-to-middle-age subjects: prevalence and factors involved

PURPOSE

To investigate the prevalence of orthostatic hypertension and the association of the blood pressure (BP) level, supine BP decline, and white-coat effect with the orthostatic pressor response.

METHODS

We studied 1275 young-to-middle-age individuals with stage-1 hypertension. Orthostatic response was assessed three times over a 3 month period. The white-coat effect was assessed at baseline and after 3 months, and was calculated as the difference between office and average 24 h BP. In 660 participants, urinary epinephrine and norepinephrine were also measured.

RESULTS

An orthostatic systolic BP increase ≥ 20 mmHg was observed in 0.6-1.2% of the subjects during the three visits. Using the 20 mmHg cut-off, the prevalence of orthostatic hypertension was 0.6%. An orthostatic BP increase of ≥ 5 mmHg was found in 14.4% of participants. At baseline, the orthostatic response to standing showed an independent negative association with the supine BP level (p < 0.001), the supine BP change from the first to third measurement (p < 0.001), and the white-coat effect (p < 0.001). Similar results were obtained in the 1080 participants assessed at the third visit. Urinary epinephrine showed higher values in the top BP response decile (systolic BP increase ≥ 6 mmHg, p = 0.002 versus rest of the group).

CONCLUSION

An orthostatic systolic BP reaction ≥ 20 mmHg is rare in young adults. However, even lower BP increases may be clinically relevant. The BP level, the supine BP decline over repeated measurement, and the white-coat effect can influence the estimate of the BP response to standing and should be considered in clinical and pathogenetic studies.