Cardiovascular risk assessment using pulse pressure in the first national health and nutrition examination survey (NHANES I)

Flow-mediated dilation and exercise blood pressure in healthy adolescents

OBJECTIVES

Exercise blood pressure is a robust predictor of cardiovascular disease risk. Endothelial dysfunction occurs early in development of cardiovascular disease and is associated with greater exercise blood pressure in adults. However, it is not yet clear whether endothelial function is associated with exercise blood pressure in youth. The purpose of this study was to examine the relationship between endothelial function, indexed by brachial artery flow-mediated dilation, and submaximal exercise blood pressure in healthy adolescents.

DESIGN

Cross-sectional study.

METHODS

Adolescents (N=45) completed a graded submaximal treadmill test. Blood pressure was measured during rest and each exercise stage. Ultrasound measurement of brachial artery flow-mediated dilation was completed on a separate visit. Pearson correlations and multiple regression were used to assess the unadjusted and multivariate adjusted associations between flow-mediated dilation and exercise blood pressure, respectively.

RESULTS

Lower flow-mediated dilation was associated with lower diastolic blood pressure (r=0.37, p=0.01) and greater pulse pressure (r=-0.38, p=0.01) during exercise. The significance did not change when adjusting for age, gender, fitness, or resting blood pressure. Exploratory analyses suggest that flow-mediated dilation was associated with exercise diastolic blood pressure primarily among adolescents with low resting diastolic blood pressure.

CONCLUSIONS

Studies in youth are important to understand the early pathogenesis of cardiovascular disease. Findings from this study suggest that endothelial function may play a role in regulating blood pressure responses during submaximal exercise in healthy adolescents.

Body weight telemetry is useful to reduce interdialytic weight gain in patients with end-stage renal failure on hemodialysis

Lacking compliance with liquid intake restrictions is one of the major problems in patients on hemodialysis and causes an increased mortality. In 120 patients on hemodialysis with an average interdialytic weight gain (IWG) exceeding 1.5 kg on at least 2 days during the 4 weeks preceding the intervention, the effect of telemetric body weight measurement (TBWM) on IWG, ultrafiltration rate, and blood pressure was evaluated over a period of 3 months. Patients of the telemetric group (TG) were supplied with automatic scales, which transferred the weight via telemetry on a daily basis. In the case of IWG of more than 0.75 kg/24 h, a telephonic contact was made as required, and in the case of an IWG of more than 1.5 kg, telephonic contacting was obligatory along with the advice of a liquid intake restriction to 0.5 L/day until the next dialysis. The patients of the control group (CG) received standard treatment without telemetric monitoring. We examined specific data of the second interdialytic interval (IDI2) and the average within 1 week. The average difference of IWG between TG and CG was not significant before the start of the study but 0.2 kg (p=0.027) (IDI2)/0.27kg (p=0.001) (WP) at the end of the study, respectively. The average difference in the ultrafiltration rate within 1 week was 19.0 mL/h (p=0.282) (IDI2)/8.2 mL/h (p=0.409) before the start of the study but 28.4 mL/h (p=0.122) (IDI2)/30.9 mL/h (p=0.004) at the end of the study, respectively. Thus, TBWM is a feasible method for optimizing the IWG and reducing the ultrafiltration rate.

Association between hypertension and chronic arsenic exposure in drinking water: a cross-sectional study in Bangladesh

Chronic arsenic exposure and its association with hypertension in adults are inconclusive and this cross-sectional study investigated the association. The study was conducted between January and July 2009 among 1,004 participants from 1,682 eligible women and men aged ≥30 years living in rural Bangladesh who had continuously consumed arsenic-contaminated drinking water for at least 6 months. Hypertension was defined as systolic blood pressure ≥140 mmHg (systolic hypertension) and diastolic blood pressure ≥90 mmHg (diastolic hypertension). Pulse pressure was calculated by deducting diastolic from systolic pressure and considered to be increased when the difference was ≥55 mmHg. The prevalence of hypertension was 6.6% (95% CI: 5.1-8.3%). After adjustment for other factors, no excess risk of hypertension was observed for arsenic exposure >50 μg/L or to that of arsenic exposure as quartiles or as duration. Arsenic concentration as quartiles and >50 μg/L did show a strong relationship with increased pulse pressure (adjusted OR: 3.54, 95% CI: 1.46-8.57), as did arsenic exposure for ≥10 years (adjusted OR: 5.25, 95% CI: 1.41-19.51). Arsenic as quartiles showed a dose response relationship with increased pulse pressure. Our study suggests an association between higher drinking water arsenic or duration and pulse pressure, but not hypertension.

Relation of pulse pressure to long-distance gait speed in community-dwelling older adults: findings from the LIFE-P study

Background

Reduced gait speed is associated with falls, late-life disability, hospitalization/institutionalization and cardiovascular morbidity and mortality. Aging is also accompanied by a widening of pulse pressure (PP) that contributes to ventricular-vascular uncoupling. The purpose of this study was to test the hypothesis that PP is associated with long-distance gait speed in community-dwelling older adults in the Lifestyle Interventions and Independence for Elders Pilot (LIFE-P) study.

Methods

Brachial blood pressure and 400-meter gait speed (average speed maintained over a 400-meter walk at “usual” pace) were assessed in 424 older adults between the ages of 70–89 yrs at risk for mobility disability (mean age = 77 yrs; 31% male). PP was calculated as systolic blood pressure (BP) – diastolic BP.

Results

Patients with a history of heart failure and stroke (n = 42) were excluded leaving 382 participants for final analysis. When categorized into tertiles of PP, participants within the highest PP tertile had significantly slower gait speed than those within the lowest PP tertile (p<0.05). Following stepwise multiple regression, PP was significantly and inversely associated with 400-meter gait speed (p<0.05). Other significant predictors of gait speed included: handgrip strength, body weight, age and history of diabetes mellitus (p<0.05). Mean arterial pressure, systolic BP and diastolic BP were not predictors of gait speed.

Conclusions

Pulse pressure is associated long-distance gait speed in community-dwelling older adults. Vascular senescence and altered ventricular-vascular coupling may be associated with the deterioration of mobility and physical function in older adults.

Virtual patients and sensitivity analysis of the Guyton model of blood pressure regulation: towards individualized models of whole-body physiology

Mathematical models that integrate multi-scale physiological data can offer insight into physiological and pathophysiological function, and may eventually assist in individualized predictive medicine. We present a methodology for performing systematic analyses of multi-parameter interactions in such complex, multi-scale models. Human physiology models are often based on or inspired by Arthur Guyton's whole-body circulatory regulation model. Despite the significance of this model, it has not been the subject of a systematic and comprehensive sensitivity study. Therefore, we use this model as a case study for our methodology. Our analysis of the Guyton model reveals how the multitude of model parameters combine to affect the model dynamics, and how interesting combinations of parameters may be identified. It also includes a "virtual population" from which "virtual individuals" can be chosen, on the basis of exhibiting conditions similar to those of a real-world patient. This lays the groundwork for using the Guyton model for in silico exploration of pathophysiological states and treatment strategies. The results presented here illustrate several potential uses for the entire dataset of sensitivity results and the "virtual individuals" that we have generated, which are included in the supplementary material. More generally, the presented methodology is applicable to modern, more complex multi-scale physiological models.

Cardiovascular risk in pediatric type 1 diabetes: sex-specific intima-media thickening verified by automatic contour identification and analyzing systems

OBJECTIVES

To improve screening and quantification of subclinical atherosclerosis in children and adolescents with type 1 diabetes (T1D), we investigated the distribution of cardiovascular risk factors (cRFs) and carotid intima-media thickness (cIMT) percentiles with regard to sex-specific differences.

METHODS

This cross-sectional analysis included clinical parameters, blood lipids, and B-mode ultrasound examination of the bilateral mean cIMT using an automatic contour identification procedure combined with computerized analysis.

RESULTS

A total of 270 patients were eligible for evaluation (126 females, mean age 13.7 yr; 144 males, mean age 13.8 yr). In the total group, cIMT was significantly related to sex and diabetes duration but not to age. In males, cIMT was significantly higher than in females and sex-specific cIMT percentiles were calculated. Both pulse pressure and diabetes duration in boys and low-density lipoprotein (LDL)-cholesterol, hemoglobin A1c (HbA1c), and diabetes duration in girls showed a significant association with cIMT.

CONCLUSIONS

On the basis of sex differences of cRFs and cIMT in pediatric T1D, the assessment of sex-specific IMT percentiles facilitates a differentiated interpretation of subclinical atherosclerosis. The underlying diabetes and additional cRFs seem to be more important determinants of intima-media thickening than age. To improve the comparability of IMT measurements of relevant studies, the international harmonization of IMT measurements should be aimed for.

Aortic stiffness is reduced beyond blood pressure lowering by short-term and long-term antihypertensive treatment: a meta-analysis of individual data in 294 patients

BACKGROUND

Arterial stiffness is an independent predictor of cardiovascular events and mortality in hypertensive patients. The influence of different antihypertensive drug classes on improving arterial stiffness beyond blood pressure reduction is not widely available. We aimed to determine whether the artery stiffness can be improved because of antihypertensive treatments independently of blood pressure lowering.

METHODS

We conducted a meta-analysis of individual data from 15 randomized, controlled, double-blind, parallel group trials performed in our laboratory between 1987 and 1994. The primary endpoint was the changes of carotid-femoral pulse wave velocity (PWV) after treatment in 294 patients with mild-to-moderate essential hypertension untreated. Treatments tested were placebo (n = 88), angiotensin-converting enzyme inhibitors (ACEIs) (n = 75), calcium antagonists (n = 75), beta-blocker (n = 30), and diuretic (n = 26).

RESULTS

In the short-term and long-term trials, PWV decreased significantly by -0.75 and -1.3 m/s in the active treatment group compared with by +0.17 and -0.44 m/s in the placebo group, respectively. Active treatment was independently related to the changes in PWV and explained 5 and 4% of the variance in the short-term and long-term trials, respectively. In the short-term trials, ACEIs were more effective than calcium antagonists and placebo on improving arterial stiffness. In the long-term trials, ACEI, calcium antagonists, beta-blocker, and diuretic reduced significantly PWV compared to placebo.

CONCLUSION

Our study shows that antihypertensive treatments improve the arterial stiffness beyond their effect on blood pressure.

Risk factors for four-year incidence and progression of age-related macular degeneration: the los angeles latino eye study

PURPOSE

To identify risk factors for 4-year incidence and progression of age-related macular degeneration (AMD) in adult Latinos.

DESIGN

Population-based prospective cohort study.

METHODS

Participants, aged 40 or older, from The Los Angeles Latino Eye Study (LALES) underwent standardized comprehensive ophthalmologic examinations at baseline and at 4 years of follow-up. Age-related macular degeneration was detected by grading 30-degree stereoscopic fundus photographs using the modified Wisconsin Age-Related Maculopathy Grading System. Multivariate stepwise logistic regression was used to examine the independent association of incidence and progression of AMD and baseline sociodemographic, behavioral, clinical, and ocular characteristics.

RESULTS

Multivariate analyses revealed that older age (OR per decade of age: 1.52; 95% CI: 1.29, 1.85) and higher pulse pressure (OR per 10 mm Hg: 2.54; 95% CI: 1.36, 4.76) were independently associated with the incidence of any AMD. The same factors were associated with early AMD, soft indistinct drusen, and retinal pigmentary abnormalities. Additionally, presence of clinically diagnosed diabetes mellitus was independently associated with increased retinal pigment (OR: 1.66; 95% CI: 1.01, 2.85), and male gender was associated with retinal pigment epithelial depigmentation (OR 2.50; 95% CI: 1.48, 4.23). Older age (OR per decade of age: 2.20; 95% CI: 1.82, 2.67) and current smoking (OR: 2.85; 95% CI: 1.66, 4.90) were independently associated with progression of AMD.

CONCLUSIONS

Several modifiable risk factors were associated with 4-year incidence and progression of AMD in Latinos. The results suggest that interventions aimed at reducing pulse pressure and promoting smoking cessation may reduce incidence and progression of AMD, respectively.

Localised micro-mechanical stiffening in the ageing aorta

Age-related loss of tissue elasticity is a common cause of human morbidity and arteriosclerosis (vascular stiffening) is associated with the development of both fatal strokes and heart failure. However, in the absence of appropriate micro-mechanical testing methodologies, multiple structural remodelling events have been proposed as the cause of arteriosclerosis. Therefore, using a model of ageing in female sheep aorta (young: <18 months, old: >8 years) we: (i) quantified age-related macro-mechanical stiffness, (ii) localised in situ micro-metre scale changes in acoustic wave speed (a measure of tissue stiffness) and (iii) characterised collagen and elastic fibre remodelling. With age, there was an increase in both macro-mechanical stiffness and mean microscopic wave speed (and hence stiffness; young wave speed: 1701 ± 1 m s⁻¹, old wave speed: 1710 ± 1 m s⁻¹, p < 0.001) which was localized to collagen fibril-rich regions located between large elastic lamellae. These micro-mechanical changes were associated with increases in both collagen and elastic fibre content (collagen tissue area, young: 31 ± 2%, old: 40 ± 4%, p < 0.05; elastic fibre tissue area, young: 55 ± 3%, old: 69 ± 4%, p < 0.001). Localised collagen fibrosis may therefore play a key role in mediating age-related arteriosclerosis. Furthermore, high frequency scanning acoustic microscopy is capable of co-localising micro-mechanical and micro-structural changes in ageing tissues.

[Effects of moxibustion on physiological indices and autonomic nervous symptoms in adults with prehypertension]

PURPOSE

This study was done to examine the effects of moxibustion on physiological indices, such as 24-hr blood pressure, pulse pressure, and pulse rate, and autonomic nervous symptoms among adults with prehypertension.

METHODS

Participants were adults whose systolic and diastolic blood pressures were in the prehypertension stage and were not under treatment for the condition. Both experimental and control group consisted of 13 participants who were taking classes on acupuncture and moxibustion at a private institute. The experimental group received moxibustion once a day for 15 min, at least 5 days a week for 8 weeks. The results were analyzed using χ(2)-test, t-test, Fisher's exact test, Wilcoxon rank sum test and repeated measures ANOVA with the SAS program. Bonferroni correction method was adopted for multiple comparisons.

RESULTS

No significant change was observed in the 24-hr systolic and diastolic blood pressure between the two groups. Differences in the 24-hr pulse pressure and pulse rate were also not significant. However, significant decreases in headache, symptoms of flushing and fatigue were observed in the experimental group.

CONCLUSION

The results suggest that moxibustion contributes to alleviating symptoms such as headache, flushing and fatigue associated with the autonomic nervous system among adults with prehypertension.

Metabolic syndrome and new onset diabetes after transplantation in kidney transplant recipients

BACKGROUND

Metabolic syndrome (MS) and new onset diabetes after transplant (NODAT) are common in kidney transplant patients. We studied the relationship between the two conditions and their impact on metabolic and cardiovascular risk profiles.

METHODS

All non-diabetic patients transplanted between 1999 and 2005 who were followed up to 2006 were included. MS and NODAT were determined. Kaplan-Meier survival and various regression analyses were performed to determine the clinical correlates for both conditions and their association with various cardiovascular risk factors.

RESULTS

Among 591 patients, 314 (53.1%) had MS and 90 (15.2%) developed NODAT. The two conditions were highly associated with each other as 84 patients with NODAT also had MS (14.2%). Elevated body mass index and fasting glucose levels at transplant were risk factors for both conditions, whereas weight gain after transplant was associated only with MS. African American, old age, and hypertension-related ESRD were risk factors for NODAT. Finally, the presence of MS was associated with reduced kidney function and elevated uric acid levels, whereas the presence of NODAT with elevated pulse pressure.

CONCLUSIONS

MS and NODAT are highly prevalent and significantly associated with impaired metabolic and cardiovascular risk profiles. Early identification of such conditions may facilitate targeted therapeutic intervention.

Diastolic dysfunction, cardiovascular aging, and the anesthesiologist

As the number of persons aged 65 years and older continues to increase, the anesthesiologist will more frequently encounter this demographic. Cardiovascular changes that occur in this patient population present difficult anesthetic challenges and place these patients at high risk of perioperative morbidity and mortality. The anesthesiologist should be knowledgeable about these age-related cardiovascular changes, the pathophysiology underlying them, and the appropriate perioperative management. Whether presenting for cardiac or general surgery, the anesthesiologist must identify patients with altered physiology as a result of aging or diastolic dysfunction and be prepared to modify the care plan accordingly. With a directed preoperative assessment that focuses on certain aspects of the cardiovascular system, and the assistance of powerful echocardiographic tools such as tissue Doppler, this can be achieved.

Multichannel pulsed Doppler signal processing for vascular measurements in mice

The small size, high heart rate and small tissue displacement of a mouse require small sensors that are capable of high spatial and temporal tissue displacement resolutions and multichannel data acquisition systems with high sampling rates for simultaneous measurement of high fidelity signals. We developed and evaluated an ultrasound-based mouse vascular research system (MVRS) that can be used to characterize vascular physiology in normal, transgenic, surgically altered and disease models of mice. The system consists of multiple 10/20MHz ultrasound transducers, analog electronics for Doppler displacement and velocity measurement, signal acquisition and processing electronics and personal computer based software for real-time and off-line analysis. In vitro testing of the system showed that it is capable of measuring tissue displacement as low as 0.1mum and tissue velocity (mum/s) starting from 0. The system can measure blood velocities up to 9m/s (with 10MHz Doppler at a PRF of 125kHz) and has a temporal resolution of 0.1 milliseconds. Ex vivo tracking of an excised mouse carotid artery wall using our Doppler technique and a video pixel tracking technique showed high correlation (R(2)=0.99). The system can be used to measure diameter changes, augmentation index, impedance spectra, pulse wave velocity, characteristic impedance, forward and backward waves, reflection coefficients, coronary flow reserve and cardiac motion in murine models. The system will facilitate the study of mouse vascular mechanics and arterial abnormalities resulting in significant impact on the evaluation and screening of vascular disease in mice.

Decreased pulse pressure during hemodialysis is associated with improved 6-month outcomes

Pulse pressure is a well established marker of vascular stiffness and is associated with increased mortality in hemodialysis patients. Here we sought to determine if a decrease in pulse pressure during hemodialysis was associated with improved outcomes using data from 438 hemodialysis patients enrolled in the 6-month Crit-Line Intradialytic Monitoring Benefit Study. The relationship between changes in pulse pressure during dialysis (2-week average) and the primary end point of non-access-related hospitalization and death were adjusted for demographics, comorbidities, medications, and laboratory variables. In the analyses that included both pre- and post-dialysis pulse pressure, higher pre-dialysis and lower post-dialysis pulse pressure were associated with a decreased hazard of the primary end point. Further, every 10 mm Hg decrease in pulse pressure during dialysis was associated with a 20% lower hazard of the primary end point. In separate models that included pulse pressure and the change in pulse pressure during dialysis, neither pre- nor post-dialysis pulse pressure were associated with the primary end point, but each 10 mm Hg decrease in pulse pressure during dialysis was associated with about a 20% lower hazard of the primary end point. Our study found that in prevalent dialysis subjects, a decrease in pulse pressure during dialysis was associated with improved outcomes. Further study is needed to identify how to control pulse pressure to improve outcomes.

Pulse pressure predicts mortality in elderly patients

BACKGROUND

Pulse pressure (PP) values increase with age. The impact of PP on mortality in elderly patients has not been established.

OBJECTIVES

To evaluate the effect of PP on mortality among very elderly hospitalized patients.

DESIGN

A prospective clinical study.

PARTICIPANTS AND MEASUREMENTS

The medical records of 420 inpatients aged >60 (187 males, mean age of 81.4 +/- 7 years) hospitalized in an acute geriatric ward were reviewed. Patients were followed up for a mean of 3.46 +/- 1.87 years. Mortality data were extracted from death certificates. Using relative operating characteristic (ROC) curves, we identified PP of 62.5 mmHg as a cutoff point. Subjects were categorized as having low PP (< or = 62.5 mmHg; N = 116) or high PP (>62.5 mmHg; N = 304).

MAIN RESULTS

The mortality rate was greater in patients with high PP than in those with low PP. During the follow-up, 201 patients died, 155 patients (51%) in the high PP group and 46 patients (39.7%) in the low PP group (p = 0.038). Pulse pressure was associated with all-cause mortality (HR = 1.69, 95% CI = 1.19-2.38, p = 0.003) even after controlling for gender, age, diabetes mellitus, atrial fibrillation and heart rate.

CONCLUSION

High PP is an independent predictor of mortality among elderly hospitalized patients.

Genomic susceptibility Loci for brain atrophy, ventricular volume, and leukoaraiosis in hypertensive sibships

OBJECTIVE

To localize susceptibility genes for alterations in brain structure associated with risk of stroke and dementia. We conducted genomewide linkage analyses for magnetic resonance imaging (MRI) measures of brain atrophy, ventricular, and subcortical white matter hyperintensity (leukoaraiosis) in 689 non-Hispanic white (673 sibling pairs; median age, 61 years) and 544 non-Hispanic black participants (503 sibling pairs; median age, 64 years) from sibships with at least 2 members with essential hypertension.

DESIGN, SETTING, AND PATIENTS

We determined brain, ventricular, and leukoaraiosis volumes from axial fluid-attenuated inversion recovery MRI; we calculated brain atrophy as the difference between total intracranial and brain volumes. Microsatellite markers (n = 451) distributed across the 22 autosomes were genotyped, and we used variance components methods to estimate heritability and assess evidence of genetic linkage for each MRI measure.

MAIN OUTCOME MEASURES

Brain atrophy ventricular volume, and leukoaraiosis determined from fluid-attenuated inversion recovery MRI.

RESULTS

In both races, the heritability of each MRI measure was statistically greater than 0 (P < .001), ranging in magnitude from 0.42 (for ventricular volume in blacks) to 0.69 (for brain atrophy in blacks). Based on multipoint logarithm of odds scores (MLS), the strongest evidence of genetic linkage was observed for brain atrophy on chromosomes 1 (MLS, 3.49 at 161 cM; P < .001) and 17 (MLS, 3.08 at 18 cM; P < .001) in whites; for ventricular volume on chromosome 12 (MLS, 3.67 at 49 cM; P < .001) in blacks and chromosome 10 (MLS, 2.47 at 110 cM; P < .001) in whites; and for leukoaraiosis on chromosome 11 (MLS, 2.21 at 118 cM; P < .001) in whites and chromosome 22 (MLS, 2.02 at 36 cM; P = .001) in blacks.

CONCLUSIONS

The MRI measures of structural brain injury are heritable in non-Hispanic black and white sibships ascertained through hypertensive sibling pairs. The susceptibility loci for brain atrophy, ventricular volume, and leukoaraiosis identified by linkage analyses differ among MRI measures and between races.

The pulsatile component of blood pressure – Its role in the pathogenesis of atherosclerosis

Pulse pressure (PP) is traditionally believed to increase cardiovascular risk because of an increase in afterload leading to left ventricular hypertrophy. It has also been emphasized that low diastolic blood pressure, being in part responsible for high PP, leads to an impairment of myocardial perfusion with all its adverse consequences. More recently, however, a direct role of pulsatile blood pressure changes in the pathogenesis of atherosclerosis and its complications has become better known. Experimental studies indicate that there is a cause-and-effect type of relationship between the pulsatile component of blood pressure and atherosclerotic process. A significant relationship between the parameters of the pulsatile blood pressure component and the extent of coronary atherosclerosis was also demonstrated. Currently the presence of a bidirectional link between atherosclerosis and PP is commonly postulated, meaning that an increased PP may be both a cause and an effect of atherosclerosis. This may result in a vicious circle wherein the pulsatile blood pressure component induces/enhances the development of atherosclerosis, which in its turn reduces the arterial compliance and enhances pulse wave reflection, thereby leading to an increase in PP. Currently new drug classes are being investigated, which might reduce the pulsatile blood pressure component without changing mean blood pressure level. Their clinical usefulness should become known over the next few years.

Forward and backward waves in the arterial system: impedance or wave intensity analysis?

Both impedance analysis and wave intensity analysis are used to separate measured pressure and flow waveforms into their forward and backward components. The separation is sensitive to the characteristic impedance or wave speed determined from the data. In all other aspects, the results are identical.

Pulse pressure and adverse outcomes in women: a report from the Women's Ischemia Syndrome Evaluation (WISE)

BACKGROUND

Recent data suggest that brachial pulse pressure (PP) may be a better predictor of outcome than systolic or diastolic blood pressure (SBP/DBP). We sought to investigate the relative contributions of these indices to risk for adverse outcomes in women with suspected coronary artery disease (CAD) and myocardial ischemia.

METHODS

Among 857 women referred for angiography for suspected myocardial ischemia, baseline evaluations were performed, and the women were followed for clinical outcome. Relationships between baseline characteristics, blood pressure components, and outcomes were evaluated. Separate multivariate stepwise Cox regression models for PP and SBP (expressed in 10 mm Hg increments) were constructed and included covariates significantly associated with adverse outcomes.

RESULTS

After 5.2 years (mean), univariate testing identified higher PP associated with higher risk for cardiovascular (CV) mortality and adverse CV outcomes than SBP, DBP, or mean arterial pressure (MAP). Multivariate modeling identified both PP and SBP associated with adverse CV outcomes, but only PP was significantly associated with higher CV mortality. When both PP and SBP were included in the model, only PP remained an independent predictor of adverse outcomes for CV events.

CONCLUSIONS

In women with suspected CAD and myocardial ischemia, PP is a stronger predictor of adverse outcomes than SBP, DBP, or MAP with an 18% excess mortality risk for every 10 mm Hg increase in PP. Further investigations into pathophysiologic mechanisms and specific pharmacologic approaches to modifying this novel target are warranted.

Ambulatory arterial stiffness index is increased in hypertensive childhood disease

Arterial hypertension in adults is often associated with an increased arterial stiffness, which correlates with the ambulatory arterial stiffness index (AASI) as derived from ambulatory blood pressure (BP) measurements. The purpose of this study was to demonstrate whether children with diagnosed hypertension have an increased AASI as in hypertensive adults. AASI was calculated from 185 ambulatory BP measurements of 114 hypertensive and 71 normotensive, healthy children. Hypertensive children had higher AASI values compared with their normotensive healthy counterparts (0.370 +/- 0.120 versus 0.204 +/- 0.199, p < 0.0001). Children with longer duration of hypertension or a history of primary or secondary aortic coarctation displayed even more elevated AASI values. A receiver operator curve derived cut-off of AASI set at 0.301 distinguished (p < 0.0001) hypertensive from normotensive children with an odds ratio of 8.2, a sensitivity of 81%, and a specificity of 65%. Moreover, AASI correlated with pulse and systolic BP. In conclusion, AASI is elevated in hypertensive children and correlates with the duration and the origin of hypertension in childhood.

Arterial stiffness and inflammatory response to psychophysiological stress

The processes through which psychological stress influences cardiovascular disease are poorly understood, but may involve activation of hemodynamic, neuroendocrine and inflammatory responses. We assessed the relationship between carotid arterial stiffness and inflammatory responses to acute psychophysiologic stress. Participants were 155 healthy men and women aged 55.3, SD 2.7 years. Blood samples for the assessment of plasma fibrinogen, tumor necrosis factor (TNF) alpha and interleukin (IL) 6 were drawn at baseline, immediately following standardized behavioral tasks, and 45 min later. Carotid artery stiffness was measured ultrasonically three years later, and blood pressure and heart rate responses were recorded. The tasks induced substantial increases in blood pressure and heart rate, together with increased fibrinogen, TNFalpha and IL-6 concentration. Carotid stiffness was positively associated with body mass, waist/hip ratio, blood pressure, low density lipoprotein cholesterol, and C-reactive protein, and inversely with high density lipoprotein and grade of employment. Baseline levels of inflammatory variables were not related to carotid artery stiffness. But carotid stiffness was greater in participants with larger fibrinogen (p=0.037) and TNFalpha (p=0.036) responses to psychophysiological stress. These effects were independent of age, gender, grade of employment, smoking, body mass, waist/hip ratio, systolic and diastolic pressure, high and low density lipoprotein cholesterol, and C-reactive protein. There were no associations between carotid stiffness and stress responses in IL-6, blood pressure, or heart rate. We conclude that individual differences in inflammatory responses to psychophysiological stress are independently related to structural changes in artery walls that reflect increased cardiovascular disease risk.

Cumulative community-level lead exposure and pulse pressure: the normative aging study

BACKGROUND

Pulse pressure increases with age in industrialized societies as a manifestation of arterial stiffening. Lead accumulates in the vasculature and is associated with vascular oxidative stress, which can promote functional and structural vascular disease.

OBJECTIVES

We tested the hypothesis that cumulative community-level lead exposure, measured with K-X-ray fluorescence, is associated with pulse pressure in a cohort of adult men.

METHODS AND RESULTS

In a cross-sectional analysis of 593 men not treated with antihypertensive medication, tibia lead was positively associated with pulse pressure (p < 0.001). Adjusting for age, race, diabetes, family history of hypertension, education, waist circumference, alcohol intake, smoking history, height, heart rate, fasting glucose, and total cholesterol-to-HDL ratio, increasing quintiles of tibia lead remained associated with increased pulse pressure (ptrend = 0.02). Men with tibia lead above the median (19.0 microg/g) had, on average, a 4.2-mmHg (95% confidence interval, 1.9-6.5) higher pulse pressure than men with tibia lead level below the median. In contrast, blood lead level was not associated with pulse pressure.

CONCLUSIONS

These data indicate that lead exposure may contribute to the observed increase in pulse pressure that occurs with aging in industrialized societies. Lead accumulation may contribute to arterial aging, perhaps providing mechanistic insight into the observed association of low-level lead exposure with cardiovascular mortality.

Ageing of the conduit arteries

Conduit arteries become stiffer with age due to alterations in their morphology and the composition of the their major structural proteins, elastin and collagen. The elastic lamellae undergo fragmentation and thinning, leading to ectasia and a gradual transfer of mechanical load to collagen, which is 100-1000 times stiffer than elastin. Possible causes of this fragmentation are mechanical (fatigue failure) or enzymatic (driven by matrix metallo proteinases (MMP) activity), both of which may have genetic or environmental origins (fetal programming). Furthermore, the remaining elastin itself becomes stiffer, owing to calcification and the formation of cross-links due to advanced glycation end-products (AGEs), a process that affects collagen even more strongly. These changes are accelerated in the presence of disease such as hypertension, diabetes and uraemia and may be exacerbated locally by atherosclerosis. Raised MMP activity, calcification and impaired endothelial function are also associated with a high level of plasma homocysteine, which itself increases with age. Impaired endothelial function leads to increased resting vascular smooth muscle tone and further increases in vascular stiffness and mean and/or pulse pressure. The effect of increased stiffness, whatever its underlying causes, is to reduce the reservoir/buffering function of the conduit arteries near the heart and to increase pulse wave velocity, both of which increase systolic and pulse pressure. These determine the peak load on the heart and the vascular system as a whole, the breakdown of which, like that of any machine, depends more on the maximum loads they must bear than on their average. Reversing or stabilising the increased arterial stiffness associated with age and disease by targeting any or all of its causes provides a number of promising new approaches to the treatment of systolic hypertension and its sequelae, the main causes of mortality and morbidity in the developed world.

Impact of simultaneous pancreas and kidney transplantation on cardiovascular risk factors in patients with type 1 diabetes mellitus

We retrospectively investigated the impact of pancreas transplantation on cardiovascular disease risk factors in patients with type 1 diabetic end-stage renal disease (ESRD). Two cohorts of patients, 44 simultaneous pancreas and kidney transplant patients (SPK) and 30 kidney transplant-alone patients (KTA), were included. Univariate and multivariate analyses were performed. Compared with KTA patients, SPK patients had significantly lower mean arterial pressure (88.5+/-12.7 vs. 98.2+/-13.0 mmHg, P=0.002), lower pulse pressure (51.6+/-15.1 vs. 61.4+/-15.6 mmHg, P=0.008), lower low-density lipoprotein cholesterol (83.5+/-20.6 vs. 99.2+/-32.5 mg/dl, P=0.02), and required fewer lipid-lowering medications (31.8% vs. 60.0%, P=0.02). Compared with pretransplant values, only SPK patients showed significant improvement in both blood pressure and total cholesterol. We conclude that SPK significantly improves blood pressure and dyslipidemia compared with KTA in type 1 diabetic ESRD patients.

The mechanical performance and histomorphological structure of the descending aorta in hyperthyroidism

Thyroid hormones decrease systemic vascular resistance by directly affecting vascular smooth muscle relaxation. There is limited literature about their effect on the mechanical performance of the aortic wall. Therefore, the authors determined the influence of hyperthyroidism on the mechanical properties and histomorphological structure of the descending thoracic aorta in rats. Severe hyperthyroidism was induced in 20 male Wistar rats by administering L-thyroxine (T(4)) in their drinking water for 8 weeks; age-matched normal euthyroid rats acted as controls. Animals were sacrificed, and the mechanical and histomorphometrical characteristics of the descending thoracic aorta were studied. The aortic wall of hyperthyroid rats was stiffer than that of euthyroid animals at the upper physiologic levels of stress or strain (p < 0.05) but less stiff at the lower physiologic and lower levels (p < 0.05). The aorta of hyperthyroid animals compared with that of euthyroid ones showed an increase of the internal and external diameters (p < 0.05), the media area (p < 0.05), the number of smooth muscle cell nuclei (p < 0.05), and the collagen density (p < 0.05) and a decrease in the elastin laminae thickness (p < 0.001) and elastin density (p < 0.001). In hyperthyroid rats, the aortic wall was stiffer at the upper physiologic and higher levels of stress and strain. These changes correlated with microstructural changes of the aortic wall. The coexistence of hyperthyroidism with disease states or clinical conditions that predispose to increased arterial pressure may be associated with increased arterial stiffness and have undesirable consequences on the mechanical performance of the thoracic aorta and hemodynamic homeostasis. These changes could lead to an increased risk for developing vascular complications.

HEREDITARY AND ENVIRONMENTAL INFLUENCES ON ARTERIAL FUNCTION

1. With the ageing population and increasing heart failure, arterial function has been shown to contribute to cardiovascular risk because of its adverse effects on ventriculovascular coupling. Population studies have confirmed independent prognostic information of arterial stiffening on cardiovascular survival. 2. The term 'arterial function' encompasses a range of phenotypes, including measures of arterial structure/remodelling, measures of arterial wall mechanics, surrogate measures of stiffness and of wave reflection. There exists significant interaction between these measures and none is truly independent of the others. Added to this complexity is the recognition that, although arterial function has a strong genetic component, quantification requires a range of techniques from twin to family and population studies. 3. The contribution of heritability is often derived from statistical models with input from genomic scanning and candidate gene studies. Studies to date confirm a significant heritable component for the majority of phenotypes examined. However, it has also been recognized that the factors involved in blood pressure maintenance are likely to be separate to those in arterial structural degeneration with ageing. Candidate genes for arterial function go beyond those of the sympathetic and renin-angiotensin systems and include genes involved in signalling pathways and extracellular matrix modulation. 4. The present review examines the evidence for heritability of the major arterial function phenotypes with environmental and ageing modulation. A brief overview of the impact of atherosclerotic risk factors on arterial function is included.

Carotid artery intima-media thickness after raloxifene treatment

BACKGROUND

Raloxifene, a selective estrogen receptor modulator (SERM), decreases total and low-density lipoprotein cholesterol (LDL-C) in postmenopausal women and inhibits increases in intima-media thickness (IMT) in animal models. We tested whether up to 8 years exposure to raloxifene had an effect on subclinical atherosclerosis in the 4-year Multiple Outcomes of Raloxifene Evaluation (MORE) trial and the follow-up study, the 4-year Continuing Outcomes Relevant to Evista (CORE) trial.

METHODS

A subsample of postmenopausal women with osteoporosis, who had completed the MORE and CORE trials and were on average 68 years of age and 19 years postmenopausal at randomization into MORE, participated in this substudy. Within 6 months of cessation of study drug in CORE, right common carotid artery IMT (CIMT) and carotid artery stiffness and arterial compliance were measured at one of two sites (San Diego and San Francisco) using high-resolution B-mode ultrasound. CIMT and arterial stiffness measures were compared between women who had received raloxifene vs. placebo; the primary analysis included only women who were >or=80% drug compliant and had used <or=6 months of lipid-lowering medication during CORE.

RESULTS

For the primary analysis dataset (n = 89), there was no significant difference in mean CIMT between the raloxifene and placebo groups (0.83 and 0.81 mm, respectively, p = 0.62). Carotid artery stiffness and compliance were not significantly different between treatment groups (p = 0.33 and 0.59, respectively).

CONCLUSIONS

These preliminary data suggest that in this self-selected group of elderly post-menopausal women with osteoporosis who were evaluated within 6 months of cessation of study medication, there were no differences between long-term raloxifene treatment and placebo groups in several measures of subclinical atherosclerosis.

Association of clinic and ambulatory blood pressure with vascular damage in the elderly: the EPICARDIAN study

OBJECTIVES

In middle-aged adults, vascular damage correlates better with ambulatory than with clinic blood pressure. This study aimed to determine whether vascular damage evaluated by carotid ultrasonography in the elderly is also more closely related to ambulatory than to clinic blood pressure, and which blood pressure variables are better associated with vascular damage.

METHODS

Cross-sectional study of 292 randomly selected >65 years old participants who underwent 24-h noninvasive ambulatory blood pressure monitoring. Blood pressure variables analyzed were (a) clinic blood pressure: systolic and diastolic blood pressure, pulse pressure; (b) ambulatory blood pressure monitoring: mean values of systolic and diastolic blood pressure, systolic and diastolic blood pressure load, pulse pressure, as well as variability, evaluated within 24 h, diurnal and nocturnal periods; and day-night blood pressure difference. A clinical history, physical examination, carotid ultrasonography and laboratory tests were performed. To estimate the relationship between blood pressure and vascular damage, univariate and multivariate analyses were performed.

RESULTS

Mean age: 73+/-6 years, 45% men, 76.7% hypertensive patients. In the simple regression analysis, the best significant correlations (P<0.05) were common carotid intima-media thickness with 24-h and nocturnal pulse pressure (r=0.32), and common carotid diameter with 24-h systolic blood pressure load (r=0.47). In the multivariate analysis, the significant associations (P<0.05) were (a) linear regression: nocturnal pulse pressure with common carotid intima-media thickness, and diurnal pulse pressure as well as 24-h systolic blood pressure load with common carotid diameter; (b) logistic regression, adjusted odds ratio: nocturnal pulse pressure and nocturnal diastolic blood pressure load with the presence of carotid atherosclerotic plaques 1.03 and 0.98, respectively.

CONCLUSIONS

In the elderly, ambulatory blood pressure monitoring is better associated with carotid damage than clinic blood pressure. Systolic blood pressure variables are the best associated, blood pressure load and pulse pressure being better associated with carotid damage than the mean levels of ambulatory blood pressure.

Mean arterial pressure: a better marker of stroke in patients with uncontrolled hypertension in rural areas of China

OBJECTIVE

The purpose of this study was to compare the association of pulse pressure (PP) and mean arterial pressure (MAP) with stroke in uncontrolled hypertensive subjects.

METHODS

A total of 9,901 uncontrolled hypertensive subjects were included in a cross-sectional study in 62 villages of Fuxin county of Liaoning Province, China.

RESULTS

Among the 9,901, 406 cases of ischemic stroke and 145 cases of cerebral hemorrhage were identified. Older age, male gender, increased SBP, higher DBP, and history of hyperlipemia were positively associated with both ischemic stroke and cerebral hemorrhage by multivariate logistic regression analysis. However, the odds rations (ORs) of drinking for ischemic stroke and cerebral hemorrhage were 0.407 (95%CI: 0.304-0.544) and 0.595 (95%CI: 0.377-0.940), respectively. An increase of 10 mmHg of MAP had ORs of 1.430 (95%CI: 1.332-1.535) for ischemic stroke and 1.359 (95%CI: 1.220-1.514) for cerebral hemorrhage. The OR of PP (per 10 mmHg increase) for ischemic stroke was 1.085 (95%CI: 1.026-1.148). Subjects with the fourth quartile of PP and MAP had ORs of 1.555 (95%CI: 1.127-2.146) ischemic stroke and 5.127 (95%CI: 3.452-7.616) for cerebral hemorrhage, with the first quartile as the reference group. The OR of the fourth quartile of MAP for cerebral hemorrhage was 5.935 (95%CI: 2.932-12.012). There was no significant association between PP and cerebral hemorrhage. In sensitivity analysis, ORs of standard MAP for ischemic stroke were higher than those of PP in each stratified age subgroup.

CONCLUSIONS

Increased MAP and PP were significant markers of ischemic stroke and cerebral hemorrhage was only associated with increased MAP. MAP was more closely associated with stroke than PP in patients with uncontrolled hypertension.

High pulse pressure and low mean arterial pressure: two predictors of death after a myocardial infarction

OBJECTIVES

Although the negative prognostic implication of a clinical history of arterial hypertension in myocardial infarction (MI) survivors is well known, the predictive role of the blood pressure (BP) regimen after MI is not well defined. The aim of this study was to investigate the prognostic significance of different BP indices in post-MI.

METHODS AND RESULTS

We evaluated the relationship between baseline systolic, diastolic, pulse and mean arterial pressure (MAP), measured by sphygmomanometry at discharge from hospital or within 3 months of an MI, and total and cardiovascular mortality in 11 116 patients enrolled in the GISSI-Prevenzione trial. Over 3.5 years of follow-up, 999 patients died, 657 of them from cardiovascular causes. Low mean and high pulse pressure were significantly associated with total and cardiovascular mortality after controlling for potential confounders in the multivariate analysis. As compared with patients with less extreme BP values, patients with MAP of 80 mmHg or less (n = 1241; 11.2%) had a 48% higher risk of cardiovascular death [95% confidenceinterval (CI) 1.16-1.87; P = 0.001] and those with pulse pressure greater than 60 mmHg (n = 958; 8.6%) had a 35% higher risk (95% CI 1.09-1.69; P = 0.007); only four subjects (0.04%) had both a high pulse pressure and a low MAP (relative risk of cardiovascular death 3.48; 95% CI 0.48-25.88; P = 0.218).

CONCLUSIONS

Our results show for the first time an additional prognostic importance of two easily measurable components of BP, definitely high pulse pressure (> 60 mmHg) and low MAP (< or = 80 mmHg), in a large sample of non-selected patients surviving MI who entered a modern programme of cardiovascular prevention.

Pulse pressure and vascular risk in the elderly: associations and clinical implications

Pulse pressure provides information beyond systolic and diastolic blood pressures, from which it is calculated. The majority of individuals older than 70 years have a widened pulse pressure resulting from age-related stiffening of the central elastic arteries and systolic hypertension. A widened pulse pressure is associated with cardiovascular risk factors such as diabetes, hypertension, and smoking. It also predicts a higher risk of subsequent cardiovascular events, stroke, renal disease, heart failure, and mortality, particularly in the elderly. The authors review the mechanisms that contribute to pulse pressure and the association between pulse pressure, vascular risk factors, and outcomes.

Can we improve cardiovascular risk prediction beyond risk equations in the physician's office?

BACKGROUND AND OBJECTIVES

Beyond a global estimation of the cardiovascular risk through the assessment of major risk factors and their integration in dedicated risk scales or equations, the use of specific markers provides additive prognostic information at an individual level, including predisposing factors, which are not included in the risk equations as well as the individual susceptibility to their long-term exposure. However, the majority of these markers require specific devices and skills, which are not widely available in primary care.

METHODS

Some clinical and/or "low-cost" parameters are shown to be valuable risk markers, and their use could refine the risk estimation in a physician's office. Several epidemiologic studies suggest the heart rate, the pulse pressure and the ankle-brachial index are effective cardiovascular risk markers. The arms systolic pressure asymmetry could also be a useful marker of risk.

RESULTS AND CONCLUSIONS

Through a general review, the authors evaluate the potential of these clinical markers, including their use in combination for more accurate risk determination.

Hypertension: a new look at an old problem

PURPOSE OF REVIEW

This review reports the specific impact that hypertension, identified by its component subtype classification, has on perioperative outcomes. Most importantly, we review the risk of systolic hypertension and pulse pressure hypertension independent of elevated diastolic blood pressure on patients undergoing cardiac surgery.

RECENT FINDINGS

Systemic hypertension is identified as a major risk factor for cardiovascular morbidity in most larger population-based studies. Nearly a third of the population in the United States has or will have some form of hypertension disease, with many under-diagnosed or under-treated. Classification of hypertensive subtypes has been well recognized as an important component for risk stratification in the ambulatory population in recent years, but remains poorly recognized in the surgical setting. We present recent data unveiling the importance of pulse pressure above that of systolic and diastolic pressures.

SUMMARY

The evidence is compelling that wide pulse pressure hypertension is a strong and an independent predictor of adverse perioperative renal, cerebral and mortality outcomes. We discuss the physiology for this important novel observation in an acute surgical patient population and provide an explanation.

Utility of second derivative of the finger photoplethysmogram for the estimation of the risk of coronary heart disease in the general population

BACKGROUND

Increased arterial stiffness has been shown to be associated with coronary heart disease (CHD). However, it remains unclear as to whether the second derivative of the finger photoplethysmogram (SDPTG), a non-invasive method for the assessment of arterial stiffness, is useful for the estimation of risk of CHD in the general population.

METHODS AND RESULTS

The SDPTG in 211 subjects (age: 63+/-15 years, range: 21-91 years, 93 males) was recorded without apparent atherosclerotic disorders from a community. The relationship between the SDPTG indices (b/a and d/a) and coronary risk factors (n=211) or the Framingham risk score (n=158, age: 60+/-12 years, range: 30-74 years, 63 males) were analyzed. The SDPTG indices significantly correlated with the Framingham risk score in both genders (b/a; r(male) =0.43, r(female) =0.54 and d/a; r(male) =-0.38, r(female) =-0.58), as well as several coronary risk factors. In the receiver operating characteristics curve analyses, the b/a discriminated high-risk subjects for CHD, who were in the highest quintile of the Framingham risk score in each gender, with a sensitivity and specificity of 0.85 and 0.58 in males and 0.83 and 0.72 in females, respectively.

CONCLUSIONS

These results suggest that the SDPTG is useful for the estimation of risk of CHD in the general population.

Ambulatory arterial stiffness index: rationale and methodology

OBJECTIVES

Increased arterial stiffness is associated with the development of cardiovascular disease and may even predict its development at an early stage. Increased pulse pressure is seen as a marker of increased arterial stiffness and can be readily measured by ambulatory blood pressure monitoring. We propose another surrogate measure of arterial stiffness derived from ambulatory blood pressure monitoring that may predict cardiovascular mortality over and above pulse pressure, namely, the dynamic relationship between diastolic and systolic blood pressure over 24 h--the ambulatory arterial stiffness index.

METHODS

Using all blood pressure readings over the 24-h period from 11 291 (5965 women; mean age 54.6 years) patients referred for ambulatory blood pressure monitoring to a blood pressure clinic, diastolic blood pressure was plotted against systolic blood pressure, and the regression slope was calculated; ambulatory arterial stiffness index was defined as one minus this regression slope.

RESULTS

Both ambulatory arterial stiffness index and pulse pressure were higher in women (0.42 vs. 0.40 and 57.0 vs. 55.3 mmHg, respectively). For the entire group, the correlation between ambulatory arterial stiffness index and pulse pressure was 0.5.

CONCLUSIONS

Ambulatory arterial stiffness index is a new measure that is readily available from ambulatory blood pressure monitoring and may provide added prognostic information for cardiovascular outcome.

The impact of pedigree structure on heritability estimates for pulse pressure in three studies

OBJECTIVES

Pulse pressure (PP) is a measure of large artery stiffness and has been shown to be an important predictor of cardiovascular morbidity and mortality. The aims of the present study were to investigate the heritability of PP in three studies, the Diabetes Heart Study (DHS), the Insulin Resistance Atherosclerosis Family Study (IRAS FS), and the NHLBI Family Heart Study (FHS), to estimate the residual heritability after inclusion of a common set of covariates, and to investigate the impact of pedigree structure on estimating heritability.

METHODS AND RESULTS

DHS is primarily a sibling pair nuclear family study design, while both IRAS FS and FHS have large pedigrees. Heritability estimates of log-transformed PP were obtained using variance component models. After adjusting for age, gender, ethnicity/center, height, diabetes status, and mean arterial pressure (MAP), heritability estimates of PP were 0.40 +/- 0.08 , 0.22 +/- 0.05, and 0.19 +/- 0.03 in DHS, IRAS FS, and FHS, respectively. The heritability estimate from DHS was significantly different from both IRAS FS and FHS (both p values <0.05). A random re-sampling technique (modified bootstrap) was used to explore the heritability in the IRAS FS and FHS data when these pedigrees were trimmed to mimic the DHS pedigree structure. The re-sampling method (mimicking a sibling pair nuclear family design in all studies) yielded PP heritability estimates of 0.37, 0.34, and 0.27 in DHS, IRAS FS, and FHS, respectively. There was no significant difference among the heritability estimates from the three studies based on the re-sampling method.

CONCLUSION

We have shown that PP has a moderately heritable component in three different studies. These data illustrate the influence of pedigree structure can have on estimating heritability. Thoughtful comparisons of heritability estimates must consider study design factors such as pedigree structure.

Long-term prognostic impact of repeated measurements over 1 year of pulse pressure and systolic blood pressure in the elderly

Systolic blood pressure (SBP) and pulse pressure (PP) have been identified in western industrialized countries as major predictors of cardiovascular events in the elderly on the basis of measurements taken at a single visit. Considering the wide variability of blood pressure (BP) in older people, this study set out to assess the prognostic significance of measurements of SBP and PP taken over several months according to a monitoring scheme mimicking routine care. A total of 444 Italian general practitioners enrolled a cohort of 3858 unselected elderly outpatients and followed them up for 10 years. BP was recorded at recruitment, 1 week later and at quarterly visits during the first year. The average BP of these six visits was used to define the patient's BP status. During the 10-year follow-up, 1561 participants died, 709 from cardiovascular diseases. Proportional hazard regression analysis, adjusted for all main prognostic factors including antihypertensive treatment, showed that for each 10-mmHg increment in SBP and PP there were, respectively, 5 and 9% increases in risk for total mortality (TM) and 9 and 13% increases in risk for cardiovascular mortality (CVM) (all P < 0.01). However, including both SBP and PP in the model, only PP showed an independent, significant relationship with TM and CVM. In conclusion, prognostic information based on repeated measurements of PP is stronger than that given by SBP and consequently should be recommended in the definition of cardiovascular risk in the elderly.

Pulse pressure is independently associated with sensorimotor peripheral neuropathy in patients with type 2 diabetes

OBJECTIVES

The mechanisms responsible for the onset and progression of sensorimotor peripheral neuropathy (SMPN) in type 2 diabetes remain largely unknown. Although a link between hypertension and SMPN has been observed, it is not clear which blood pressure (BP) component (i.e. systolic, SBP; diastolic, DBP; or pulse pressure, PP) is primarily involved. We sought to determine the relationship between BP components and parameters of nerve function in type 2 diabetes.

DESIGN

Cross-sectional study.

SETTING

Academic medical centre.

SUBJECTS

A total of 55 consecutive ambulatory patients with type 2 diabetes (age 62.6 +/-8.0 years, mean +/- SD).

INTERVENTIONS

Measurement of clinic BP and 10 neurophysiological parameters: motor nerve conduction velocity (NCV; median, ulnar, posterior tibial and peroneal nerve), sensory amplitude (AMP) and latency (LAT; median, ulnar and sural nerve).

RESULTS

Univariate analysis showed that age, diabetes duration, SBP and PP were negatively correlated with nerve function. Regression analysis showed that, after correcting for age, duration of diabetes, glycated haemoglobin, body mass index, microalbuminuria and SBP, PP was independently and negatively associated with NCV (median, P =0.011; ulnar, P = 0.001; peroneal, P = 0.006 and posterior tibial, P = 0.005) and signal AMP (ulnar, P = 0.027; sural, P = 0.055), and positively associated with signal LAT (median, P = 0.083; sural, P = 0.021). SBP was negatively associated with signal AMP (median, P = 0.012) and positively associated with LAT (ulnar, P = 0.018). By contrast, DBP failed to show any significant correlation with nerve function.

CONCLUSIONS

The PP is strongly associated with neurophysiological parameters of nerve function in patients with type 2 diabetes. This relationship is independent of traditional risk factors and other BP components.

Pulse Pressure and Cardiovascular Events in Postmenopausal Women With Coronary Heart Disease

BACKGROUND

Pulse pressure (PP) has been shown to predict risk for cardiovascular events in men; however, this association has not been well established in women. Hormone replacement therapy may improve arterial compliance, but findings from cross-sectional and prospective studies report inconsistent results. We sought to examine the relationship between PP and risk for cardiovascular events, and to determine the effect of hormone therapy on PP in postmenopausal women with coronary heart disease (CHD).

METHODS AND RESULTS

A total of 2,763 postmenopausal women (mean age, 66 +/- 7 years [+/- SD]) with CHD in the Heart and Estrogen/Progestin Replacement Study, a randomized, placebo-controlled, secondary CHD prevention trial of estrogen plus progestin, were followed up on average for 4.1 years. BP was measured at baseline and annually. Mean baseline PP was 62 +/- 16 mm Hg. There were 361 myocardial infarctions (MIs) or CHD deaths, 265 hospitalizations for congestive heart failure (CHF), and 215 strokes or transient ischemic attacks (TIAs). Women in the highest quartile of PP at baseline had a 47% increase in risk for MI or CHD death and more than a twofold increase in risk for stroke and TIA events or hospitalization for CHF (p < 0.01 for each outcome). After adjustment for other cardiovascular risk factors and mean arterial pressure, PP remained significantly associated with incident stroke or TIA events (odds ratio, 1.25; p = 0.02) and hospitalizations for CHF (odds ratio, 1.31; p < 0.01) but not with MI or CHD death. After adjustment for diastolic BP, systolic BP was similarly associated with stroke or TIA (odds ratio, 1.30; p < 0.01) and hospitalized CHF (odds ratio, 1.30; p < 0.01) and was also weakly associated with risk for MI and CHD death (odds ratio, 1.18; p = 0.02). Mean PP was 1- to 2-mm Hg higher in women randomized to hormone replacement therapy vs those receiving placebo (p < 0.01).

CONCLUSIONS

PP had predictive value for CHF and stroke or TIA, but not MI or CHD death in this cohort of postmenopausal women with CHD. Use of hormone replacement therapy produced a small, statistically significant increase in PP. Further research is necessary to determine the clinical utility of PP as a potential therapeutic target.