Pulse pressure: Is this a clinically useful risk factor?

The biological age model for evaluating the degree of aging in centenarians

BACKGROUND

Biological age (BA) has been used to assess individuals' aging conditions. However, few studies have evaluated BA models' applicability in centenarians.

METHODS

Important organ function examinations were performed in 1798 cases of the longevity population (80∼115 years old) in Hainan, China. Eighty indicators were selected that responded to nutritional status, cardiovascular function, liver and kidney function, bone metabolic function, endocrine system, hematological system, and immune system. BA models were constructed using multiple linear regression (MLR), principal component analysis (PCA), Klemera and Doubal method (KDM), random forest (RF), support vector machine (SVM), extreme gradient boosting (XGBoost), and light gradient boosting machine (lightGBM) methods. A tenfold crossover validated the efficacy of models.

RESULTS

A total of 1398 participants were enrolled, of whom centenarians accounted for 49.21%. Seven aging markers were obtained, including estimated glomerular filtration rate, albumin, pulse pressure, calf circumference, body surface area, fructosamine, and complement 4. Eight BA models were successfully constructed, namely MLR, PCA, KDM1, KDM2, RF, SVM, XGBoost and lightGBM, which had the worst R2 of 0.45 and the best R2 of 0.92. The best R2 for cross-validation was KDM2 (0.89), followed by PCA (0.62).

CONCLUSION

In this study, we successfully applied eight methods, including traditional methods and machine learning, to construct models of biological age, and the performance varied among the models.

Invasive aortic pulse pressure is linked to cardiac allograft vasculopathy after heart transplantation

BACKGROUND

Pulse pressure (PP) has been linked to an increased risk of extent of coronary atherosclerosis and cardiovascular events. This study aimed to investigate the contribution of aortic PP on cardiac allograft vasculopathy (CAV) progression, and cardiovascular events after heart transplantation (HTx).

METHODS

A total of 330 HTx patients (mean age 49 ± 25 years, 70.0% male) undergoing routine serial coronary intravascular ultrasound (IVUS) studies and had invasive aortic PP were enrolled. The median time from HTx to first IVUS was 13.6 months. CAV progression was assessed by IVUS as the changes (Δ) in plaque volume divided by the segment length (PV/SL), adjusted for the time between IVUS (median, 3.99 years; interquartile range, 1.99-7.20 years), and was defined as ΔPV/SL ≥0.50 mm³/mm/year. Major adverse cardiovascular event (MACE) was defined as any incidence of mortality, myocardial infarction, coronary revascularization, heart failure hospitalization, or re-transplantation.

RESULTS

Recipient age, recipient sex, and renal dysfunction were independent determinant of high aortic PP (≥ 50 mmHg). High aortic PP was an independent determinant of CAV progression [odds ratio, 1.72; 95% confidence interval (CI), 1.01-2.93; p = 0.045]. Both high aortic PP (HR 1.46, 95% CI 1.01-2.11, p = 0.044) and high baseline CAV grade on angiogram (≥1, HR 1.50, 95% CI 1.03-2.21, p = 0.037) were independently associated with MACEs over 12 years.

CONCLUSION

In post-HTx patients, high aortic PP was significantly associated with plaque progression. Both aortic PP and CAV grade are independently associated with MACE during long-term follow-up. These findings suggest that arterial stiffness and CAV can be important predictors of MACEs.

Impact of invasive aortic pulse pressure on coronary microvascular endothelial-independent dysfunction and on mortality in non-obstructive coronary artery disease

Background

Pulse pressure (PP), a raw index of arterial stiffness, is inversely related to coronary microvascular function, even among patients with non-obstructive coronary artery disease (CAD), as per non-invasive studies. We aimed to determine whether invasive aortic PP is associated with coronary microvascular endothelial dysfunction (CMED) and/or coronary microvascular endothelial independent dysfunction (CMEID) in patients with non-obstructed CAD.

Methods

We retrospectively analysed a cohort of 1894 patients (mean age, 51.2 years; 1261 (66.6%) women) who presented with chest pain and non-obstructive CAD (angiographic stenosis <50%); coronary vasoreactivity was assessed in the mid-left anterior descending artery. The patients were classified based on whether aortic PP was high (≥50 mm Hg). CMEID was defined as abnormal coronary flow reserve (<2.5) or hyperaemic myocardial resistance (>2.0 mm Hg/cm/s), CMED was defined as abnormal acetylcholine-induced per cent change of coronary blood flow (≤50%).

Results

Patients with high aortic PP had a higher rate of CMEID than those with low aortic PP (40.9 vs 25.2%, p<0.001). Conversely, aortic PP was not associated with CMED. On multivariate analysis, high aortic PP was associated with CMEID occurrence (OR 1.42, 95% CI 1.13 to 1.78; p=0.003). On follow-up (median, 150 months), all-cause death was more frequent among patients with vs without high aortic PP (20.1% vs 7.3%, log-rank p<0.001) and HR was 2.08 (95% CI 1.34 to 3.32, p=0.002) on multivariate cox regression analysis. Furthermore, among patients with low aortic PP, CMEID was an independent risk factor for all-cause mortality (HR 2.04, 95% CI 1.01 to 4.16, p=0.048).

Conclusion

In patients with non-obstructive CAD, invasive aortic PP was significantly associated with CMEID, but not with CMED. High aortic PP was an independent predictor of all-cause mortality, but CMEID was an independent risk factor in patients with low aortic PP.

Pulse pressure correlates with coronary artery calcification and risk for coronary heart disease: a study of elderly individuals in the rural region of Southwest China

Aim

This study aimed to define the relationship between pulse pressure (PP) and coronary artery calcification (CAC), a proven surrogate marker for coronary heart disease.

Patients and methods

A total of 170 participants 50–70 years of age from 11 villages of Yunnan Province of China were enrolled randomly into this study. They were examined routinely for diastolic and systolic blood pressure, PP, and CAC.

Results

The average PP in the CAC-positive group was significantly higher than that in the CAC-negative group. In the positive CAC group, there were significantly positive correlations between PP and CAC score, volume, mass, as well as density. The area under the receiver operating characteristic curve analysis showed that PP performed well in predicting CAC.

Conclusion

In conclusion, among the rural people of southwest of China, PP correlates positively with the coronary calcium Agatston score, volume, mass, and density. PP predicted CAC as well as Framingham Risk Score. The measurement of PP widening may serve as an alternative and convenient method for assessing CAC risk in rural populations with poor accessibility and economic disadvantage over coronary computed tomography scanning.

The effects of blood pressure components on cardiovascular events in a Korean hypertensive population according to age and sex: A nationwide population-based cohort study

There is no known study regarding the usefulness of each blood pressure (BP) component based on stratification by age and sex for predicting cardiovascular (CV) events among hypertensive populations without chronic kidney disease (CKD) or diabetes mellitus (DM). This study was performed to investigate the association of BP components and CV events in a Korean hypertensive population according to age and sex. A total of 22,853 Korean hypertensive participants without CKD and DM were stratified into six groups according to age [40-49, 50-59, and 60 years or older] and sex. In each group, multivariate Cox proportional regression analysis was performed to reveal the associations of BP components [systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP) and pulse pressure (PP)] with CV events. The increase in PP and decrease in DBP were significantly associated with increase of CV events in males, but neither BP component was significantly associated with risk of CV events in females. When subjects were stratified by age and sex, an increase of SBP or PP was significantly related to the increased risk of CV events in 40's male group, and only the elevation of PP was significantly associated with increase in incidence of CV events in 50's male group, while a decrease in DBP was significantly associated with increased risk of CV events in older male group. In addition, there were no the significant associations with the incidence of CV events in MAP, after stratification according to age and sex. In conclusion, this study suggests that, in hypertensive populations, BP management may need to be performed after full consideration of age and sex.

Association between pulse pressure at discharge and clinical outcomes in patients with acute myocardial infarction: From the KAMIR-Korean-NIH registry

Pulse pressure (PP) is affected by arterial stiffness and is a predictor of cardiovascular events. However, value and utility of PP assessment in patients with acute myocardial infarction (AMI) remain less clear. We aimed to evaluate the association between PP and cardiovascular events in surviving patients with AMI at discharge. A total of 11 944 surviving patients with AMI at discharge from a Korean nationwide registry were included. Blood pressure was checked just before discharge. Noncardiac death and major adverse cardiovascular events (MACEs) including cardiac death, AMI, and stroke after discharge were analyzed. The median follow-up duration was 368 (IQR 339, 388) days. The rate of MACEs and cardiac death was higher in groups with the lowest PP (PP < 20 mm Hg) and highest PP (PP ≥ 71 mm Hg) and lowest in the group with PP of 31-40 mm Hg. With PP of 31-40 mm Hg as reference, univariate analysis showed a U-shaped association between the risk of MACEs (PP ≤ 20 mm Hg: hazard ratio [HR] 2.3; PP ≥ 71 mm Hg: HR 2.7) or cardiac death (PP ≤ 20 mm Hg: HR 2.6; PP ≥ 71 mm Hg: HR 3.1) and PP. In multivariate analysis, the curve changed from being U-shaped to J-shaped, and HR for PP ≥ 71 mm Hg (1.2 for MACEs and 1.4 cardiac death) decreased and HR for PP < 20 (2.1 for MACEs and 2.4 for cardiac death) did not significantly decrease after adjustment for cardiovascular risk factors. Our findings indicate that PP is a strong independent prognostic factor of MACEs and cardiac death in surviving patients with AMI. Low PP is a more significant independent predictor of MACEs and cardiac death than high PP in surviving patients after AMI.

Heart rate, pulse pressure and mortality in patients with myocardial infarction complicated by heart failure

OBJECTIVE

To assess the relationship between heart rate (HR), pulse pressure (PP), and their association with mortality in a population of high-risk patients following acute myocardial infarction (MI).

METHODS

We performed an analysis in 22,398 patients included in "The High-Risk Myocardial Infarction Database Initiative", a database of clinical trials evaluating pharmacologic interventions in patients with MI complicated by signs of heart failure (HF) or left ventricular dysfunction. We found an interaction between HR and PP. Based on median HR and median PP, patients were divided in four categories: (1) HR < 75 bpm and PP ≥ 50 mm Hg (reference), (2) HR < 75 bpm and PP < 50 mm Hg, (3) HR ≥ 75 bpm and PP ≥ 50 mm Hg, and (4) HR ≥ 75 bpm and PP < 50 mm Hg. The association between these categories and outcomes was studied using a Cox proportional hazard model.

RESULTS

After a median follow-up of 24 (18-33) months, 3561 (16%) patients died of all-causes and 3048 (14%) patients of cardiovascular (CV) causes. In multivariate analysis, patients from the fourth category had the highest risk of all-cause mortality (hazard ratio of 1.69; 95% CI: 1.53-1.86) and CV mortality (hazard ratio of 1.78; 95% CI: 1.60-1.97).

CONCLUSIONS

There is an interaction between HR and PP in patients with HF following MI, with the highest risk being conferred by a clinical status with both an elevated HR and a lower PP. These findings identify a high-risk population likely to require an aggressive diagnostic and management strategy.

Cardiovascular health of 9-year-old IVF offspring: no association with ovarian hyperstimulation and the in vitro procedure

STUDY QUESTION

Are the in vitro procedure, ovarian hyperstimulation or a combination of these two associated with blood pressure (BP) of 9-year-old IVF children born to subfertile couples?

SUMMARY ANSWER

Our study demonstrates that ovarian hyperstimulation and the in vitro procedure are not associated with BP values in 9-year-old children born to subfertile couples.

WHAT IS KNOWN ALREADY

Possible long-term effects of IVF on child health and development have been studied relatively little. This is surprising, as it is known that environmental conditions may influence embryonic and foetal development which may result in health related problems in later life. Some studies suggested that IVF is associated with higher BP at pre-school age. Yet, it is unclear whether this may be also true for older children and if so, which component of IVF, i.e. the ovarian hyperstimulation, the embryo culture or a combination of these, attributes to this potentially less favourable BP.

STUDY DESIGN, SIZE, DURATION

The Groningen Assisted Reproductive Technology cohort-study is a prospective assessor-blinded study of children followed from before birth onwards. In total, 170 children were assessed at the age of 9 years. The attrition rate up until the 9-year-old assessment was 21%.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We evaluated cardiovascular health, focusing on BP (in mmHg and the internationally recognized percentiles of the US National High BP Education Program), heart rate and anthropometrics of 57 children born following controlled ovarian hyperstimulation-IVF/ICSI (COH-IVF/ICSI); 47 children born after modified natural cycle-IVF/ICSI (MNC-IVF/ICSI); and 66 children who were conceived naturally by subfertile couples (Sub-NC). Cardiovascular parameters were measured multiple times on one day. In addition, anthropometric data, including BMI and skinfold thickness, were collected.

MAIN RESULTS AND THE ROLE OF CHANCE

Systolic BP in mmHg did not differ between the COH-IVF/ICSI (mean 106.9, SD 6.7), MNC-IVF/ICSI (mean 104.8, SD 5.9) and Sub-NC (mean 106.3, SD 5.3) groups. In addition, systolic BP percentiles did not differ between the groups: COH-IVF/ICSI (mean 62.4, SD 20.2); MNC-IVF/ICSI (mean 56.3, SD 19.3); and Sub-NC (mean 62.3, SD17.8). Also, after adjustment for confounders BP in the three groups was similar. Heart rate and anthropometric values in the three groups did not differ. For instance, BMI values in the COH-IVF/ICSI-children were 16.3 (median value, range 13.0-24.7), in MNC-IVF/ICSI-children 16.1 (range 12.7-22.5) and in Sub-NC children 16.3 (range 12.7-24.0).

LIMITATIONS, REASONS FOR CAUTION

The size of our study groups does not allow for pertinent conclusions on the effect of ovarian hyperstimulation and the in vitro procedure. The lack of a fertile control group may be regarded as another limitation.

WIDER IMPLICATIONS OF THE FINDINGS

Our study suggests that ovarian hyperstimulation and in vitro procedures are not associated with cardiovascular health in 9-year-old. Yet, BP percentiles of the three groups were higher than the expected 50th percentile. This might indicate that children of subfertile couples have a higher BP than naturally conceived children.

STUDY FUNDING/COMPETING INTEREST(S)

The study was financially supported by the University Medical Center Groningen (UMCG), the two graduate schools of the UMCG, BCN, SHARE and the Cornelia Stichting. The sponsors of the study had no role in study design, data collection, data analysis, data interpretation or writing of the report. The authors have no conflicts of interest to declare.

Blood pressure components and incident cardiovascular disease and mortality events among Iranian adults with chronic kidney disease during over a decade long follow-up: a prospective cohort study

Background

To explore the association between systolic and diastolic blood pressure (SBP and DBP respectively) and pulse pressure (PP) with cardiovascular disease (CVD) and mortality events among Iranian patients with prevalent CKD.

Methods

Patients [n = 1448, mean age: 60.9 (9.9) years] defined as those with estimated glomerular filtration rate < 60 ml/min/1.73 m², were followed from 31 January 1999 to 20 March 2014. Multivariable Cox proportional hazard models were applied to examine the associations between different components of BP with outcomes.

Results

During a median follow-up of 13.9 years, 305 all-cause mortality and 317 (100 fatal) CVD events (among those free from CVD, n = 1232) occurred. For CVD and CV-mortality, SBP and PP showed a linear relationship, while a U-shaped relationship for DBP was observed with all outcomes. Considering 120 ≤ SBP < 130 as reference, SBP ≥ 140 mmHg was associated with the highest hazard ratio (HR) for CVD [1.68 (1.2–2.34)], all-cause [1.72 (1.19–2.48)], and CV-mortality events [2.21 (1.16–4.22)]. Regarding DBP, compared with 80 ≤ DBP < 85 as reference, the level of ≥ 85 mmHg increased risk of CVD and all-cause mortality events; furthermore, DBP < 80 mmHg was associated with significant HR for CVD events [1.55 (1.08–2.24)], all-cause [1.68 (1.13–2.5)] and CV-mortality events [3.0 (1.17–7.7)]. Considering PP, the highest HR was seen in participants in the 4th quartile for all outcomes of interest; HRs for CVD events [1.92 (1.33–2.78)], all-cause [1.71 (1.11–2.63)] and CV-mortality events [2.22 (1.06–4.64)].

Conclusions

Among patients with CKD, the lowest risk of all-cause and CV-mortality as well as incident CVD was observed in those with SBP < 140, 80 ≤ DBP < 85 and PP < 64 mmHg.

Association of blood pressure components with mortality and cardiovascular events in prehypertensive individuals: a nationwide population-based cohort study

BACKGROUND

The effects of each blood pressure index [systolic and diastolic blood pressure (SBP, DBP), pulse pressure (PP), mean arterial pressure (MAP)] on the occurrence of mortality and cardiovascular (CV) events have not yet been investigated in prehypertensive populations.

METHODS

A total of 30,258 prehypertensive Korean participants underwent periodic health examination between 2003 and 2004 were enrolled, and the associations of BP components with mortality and CV events were investigated. Moreover, based on the DBP [80 ≤ DBP <90 mmHg (N = 21,323) and DBP <80 mmHg (N = 8,935)], the effects of BP components were also evaluated.

RESULTS

Multivariate Cox analyses in prehypertensive group revealed that the hazard ratios (HRs) were 1.121 and 1.130 per 10 mmHg increase in SBP and PP for mortality, respectively. Additionally, 10 mmHg increase of SBP (HR:1.090) was still significantly, but increase of PP (HR:1.060) was marginally associated with higher incidence of CV events. However, there were no significant associations with increase in DBP or MAP on adverse clinical outcomes in prehypertensive group. In the prehypertensive subjects with DBP <80 mmHg, CV events more frequently occurred by 38.8% and 28.5% per 10 mmHg increase in SBP and PP, respectively.

CONCLUSIONS

Prehypertensive subjects might need to be cautioned when they have high SBP or PP with low DBP even in healthy populations. Key message Prehypertensive subjects should be cautioned when they have high-systolic blood pressure or pulse pressure with low-diastolic blood pressure, even without previous hypertension, diabetes mellitus or chronic kidney disease.

A Model of Blood Pressure, Heart Rate, and Vaso-Vagal Responses Produced by Vestibulo-Sympathetic Activation

Blood Pressure (BP), comprised of recurrent systoles and diastoles, is controlled by central mechanisms to maintain blood flow. Periodic behavior of BP was modeled to study how peak amplitudes and frequencies of the systoles are modulated by vestibular activation. The model was implemented as a relaxation oscillator, driven by a central signal related to Desired BP. Relaxation oscillations were maintained by a second order system comprising two integrators and a threshold element in the feedback loop. The output signal related to BP was generated as a nonlinear function of the derivative of the first state variable, which is a summation of an input related to Desired BP, feedback from the states, and an input from the vestibular system into one of the feedback loops. This nonlinear function was structured to best simulate the shapes of systoles and diastoles, the relationship between BP and Heart Rate (HR) as well as the amplitude modulations of BP and Pulse Pressure. Increases in threshold in one of the feedback loops produced lower frequencies of HR, but generated large pulse pressures to maintain orthostasis, without generating a VasoVagal Response (VVR). Pulse pressures were considerably smaller in the anesthetized rats than during the simulations, but simulated pulse pressures were lowered by including saturation in the feedback loop. Stochastic changes in threshold maintained the compensatory Baroreflex Sensitivity. Sudden decreases in Desired BP elicited non-compensatory VVRs with smaller pulse pressures, consistent with experimental data. The model suggests that the Vestibular Sympathetic Reflex (VSR) modulates BP and HR of an oscillating system by manipulating parameters of the baroreflex feedback and the signals that maintain the oscillations. It also shows that a VVR is generated when the vestibular input triggers a marked reduction in Desired BP.

Association Between Adiposity and Left Ventricular Mass in Children With Hypertension

Left ventricular hypertrophy (LVH) is prevalent among hypertensive children; however, blood pressure (BP) does not predict its presence. The authors conducted a 1-year prospective cohort study to examine the hypothesis that obesity-related risk factors are associated with left ventricular mass index (LVMI) in hypertensive children, and the association between adiposity and LVMI is mediated by BP-dependent and -independent pathways. A total of 49 hypertensive children were enrolled: 51% were overweight/obese and 41% had LVH at baseline. Children overweight/obese at baseline and follow-up had a greater LVMI increase than those of healthy weight at each visit: mean change of 6.4 g/m(2.7) vs 0.95 g/m(2.7) . Baseline body mass index z score was independently associated with LVMI change (β=4.08, 1.54-6.61; P=.002). Only pulse pressure and serum aldosterone partially mediated this relationship. Hypertensive youth manifest multiple cardiovascular disease risk factors that worsen over time despite treatment. Of these, adiposity is most associated with LVH and increasing LVMI.

Increased intima-media thickness is not associated with stiffer arteries in children

OBJECTIVE

Subclinical atherosclerosis can be assessed via sonographic measurement of intima-media thickness and carotid artery distensibility, both may already be pathologically altered in childhood. Therefore, the purpose of this study was to provide reference percentiles and investigate possible associations between alterations of intima-media thickness and distensibility.

METHODS

Carotid intima-media thickness and distensibility was measured via B- and M-mode ultrasound. Distensibility was defined by arterial compliance, elastic modulus, stiffness parameter β, and local pulse wave velocity β. Age- and height-dependent reference values were calculated separately for boys and girls among 690 (intima-media thickness) and 870 (distensibility) non-obese children aged 7-17 years.

RESULTS

Intima-media thickness and distensibility did not increase significantly with age or differ between boys and girls. Systolic blood pressure and body mass index were independent predictors of intima-media thickness, while an increased systolic blood pressure or pulse pressure was associated with stiffer arteries. Increased intima-media thickness was accompanied by higher arterial compliance and lower stiffness.

CONCLUSION

Using this healthy cohort, we describe a functional and non-pathological arterial adaptation wherein an increase in intima-media thickness is not associated with stiffer arteries.

Association of BP with Death, Cardiovascular Events, and Progression to Chronic Dialysis in Patients with Advanced Kidney Disease

BACKGROUND AND OBJECTIVE

The optimal BP target to reduce adverse clinical outcomes in patients with CKD is unclear. This study examined the relationship between BP and death, cardiovascular events (CVEs), and kidney disease progression in patients with advanced kidney disease.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The relationship of systolic BP (SBP), diastolic BP (DBP), and pulse pressure (PP) with death, CVE, and progression to long-term dialysis was examined in 1099 patients with advanced CKD (eGFR≤30 ml/min per 1.7 3m(2); not receiving dialysis) who participated in the Homocysteine in Kidney and ESRD study. That study enrolled participants from 2001 to 2003. Cox proportional hazard models were used to examine the association between BP and adverse outcomes.

RESULTS

The mean±SD baseline eGFR was 18±7 ml/min per 1.73 m(2). During a median follow-up of 2.9 years, 453 patients died, 215 had a CVE, and 615 initiated long-term dialysis. After adjustment for demographic characteristics and confounders, SBP, DBP, and PP were not associated with a higher risk of death. SBP and DBP were also not associated with CVE. The highest quartile of PP was associated with a substantial higher risk of CVE compared with the lowest quartile (hazard ratio [HR], 1.67; 95% confidence interval [95% CI], 1.10 to 2.52). The highest quartiles of SBP (HR, 1.28; 95% CI, 1.01 to 1.61) and DBP (HR, 1.36; 95% CI, 1.07 to 1.73), but not PP, were associated with a higher risk of progression to long-term dialysis compared with the lowest quartile.

CONCLUSIONS

In patients with advanced kidney disease not undergoing dialysis, higher PP was strongly associated with CVE whereas higher SBP and DBP were associated with progression to long-term dialysis. These results suggest that SBP and DBP should not be the only factors considered in determining antihypertensive therapy; elevated PP should also be considered.

Associations of blood lipid-related indices with blood pressure and pulse pressure in middle-aged men

INTRODUCTION

Low-density lipoprotein cholesterol to high-density lipoprotein cholesterol (LDL-C/HDL-C) ratio is known as a classical atherogenic index. In addition, triglycerides to HDL-C (TGs/HDL-C) ratio and lipid accumulation product (LAP) have been proposed to be good discriminators for cardiometabolic risk. The aim of this study was to determine which lipid index is most strongly associated with blood pressure and pulse pressure.

METHODS

The subjects were 36,536 Japanese men aged 35-60 years who were not receiving drug therapy for dyslipidemia. Relationships of each lipid index with blood pressure and pulse pressure were investigated by using linear and logistic regression analyses.

RESULTS

There were significant positive correlations of systolic and diastolic blood pressure and pulse pressure with the lipid-related indices such as LDL-C/HDL-C ratio, TGs/HDL-C ratio, and LAP. The correlations with LAP were significantly stronger than those with the LDL-C/HDL-C ratio and the TGs/HDL-C ratio. Odds ratios (ORs) for hypertension and high pulse pressure in subjects with versus subjects without high levels of each lipid-related index were significantly higher than the reference level of 1.00. The ORs of subjects with versus subjects without high LAP tended to be higher than the ORs of subjects with versus subjects without high LDL-C/HDL-C ratio or high TGs/HDL-C ratio. In the linear and logistic regression analyses, the associations of the lipid-related indices with pulse pressure were weaker than the corresponding associations with blood pressure.

CONCLUSION

LAP shows stronger associations with blood pressure and pulse pressure than the other lipid-related indices and is suggested to be better for discriminating the risk of hypertension.

Short-term effects of air temperature on blood pressure and pulse pressure in potentially susceptible individuals

BACKGROUND

Only few epidemiological studies have investigated the association between air temperature and blood pressure (BP) or pulse pressure (PP), with inconsistent findings. We examined whether short-term changes in air temperature were associated with changes in BP or PP in three different populations.

METHODS

Between March 2007 and December 2008, 371 systolic and diastolic BP measurements were collected in 30 individuals with type-2 diabetes mellitus (T2D), 30 persons with impaired glucose tolerance and 42 healthy individuals without a metabolic disorder from Augsburg, Germany. Hourly means of ambient meteorological data were obtained from a fixed measurement station. Personal temperature measurements were conducted using data loggers. Temperature effects were evaluated using additive mixed models adjusting for time trend and relative humidity.

RESULTS

Decreases in air temperature were associated with an increase in systolic BP, diastolic BP and PP in individuals with T2D. For example, a 1°C decrease in ambient temperature was associated with an immediate increase in systolic BP of 1.0 mmHg (95%-confidence interval: [0.5;1.4]mmHg). Effects of personally measured air temperature were similar. Temperature effects were modified by age, body mass index, gender, antihypertensive medication and whereabouts, such as being indoors.

CONCLUSIONS

We observed associations between decreases in air temperature and increases in BP as well as PP in persons with T2D indicating that these people might be potentially more susceptible to changes in air temperature. Our findings may provide a hypothesis for a mechanism between air temperature decreases and short-term increases of cardiovascular events.

Carotid plaque score and intima media thickness as predictors of stroke and mortality in hypertensive patients

The mean intima media thickness (IMT) and plaque score from carotid ultrasonography are both widely used to evaluate macrovascular atherosclerotic change. The present study sought to examine which parameter more effectively predicts patient prognosis. This hospital-based cohort study included 356 patients with essential hypertension (mean age: 62.4 ± 0.6). We investigated how the mean IMT and plaque score correlated with various parameters, including pulse wave velocity (PWV), and we assessed the ability of the mean IMT and plaque score to predict cardiovascular events and total mortality. The mean IMT and plaque score significantly correlated with systemic atherosclerotic change, target organ damage, age and PWV. Subjects with a higher mean IMT and subjects with higher plaque scores showed higher frequencies of stroke and total mortality. In addition, subjects with marginal thickening of the intima media (mean ≥ 0.7) showed a significantly higher frequency of stroke than subjects with a mean IMT of <0.7. After adjustment for traditional risk factors, plaque score was significantly and independently predictive of stroke, and the predictive ability of the plaque score for the onset of stroke was equivalent to that of PWV. The mean IMT and plaque score showed a nonsignificant trend of higher risk of mortality after adjustment for traditional risk factors. The mean IMT and plaque score were significantly correlated with systemic atherosclerotic change. We revealed that plaque score predicted the onset of stroke more accurately than the mean IMT, and the accuracy of this prediction was equivalent to that from PWV in hypertensive patients. We also showed that marginal thickening of the intima media (as measured by mean IMT) may be a predictor of stroke.

Assessment of the elasticity properties of the ascending aorta in patients with subclinical hypothyroidism by tissue Doppler imaging

OBJECTIVE: We aimed to investigate whether aortic elastic properties were affected in subclinical hypothyroidism (SCH) by using tissue Doppler imaging (TDI). SUBJECTS AND METHODS: Forty-three patients with newly diagnosed SCH and forty-eight healthy controls were included to the study. Systolic and diastolic diameters of the ascending aorta were measured by M-mode transthoracic echocardiography, and the upper wall velocities of ascending aorta and mitral annulus velocities were measured by TDI. Aortic stiffness index (ASI) and aortic distensibility were computed using the formulas accepted in literature. RESULTS: The clinical and demographic features of both groups were comparable. Aortic distensibility was significantly lower, and ASI was significantly higher in SCH patients than in controls. Systolic aortic upper wall velocity (Sao) was also significantly lower in SCH patients. Early (Eao) and late diastolic aortic upper wall (Aao) velocities did not differ between the two groups. Mitral annulus (Sm, Em, and Am) velocities were also similar between the groups. Sao was negatively correlated with ASI, and positively correlated with aortic distensibility. TSH level was positively correlated with ASI, total cholesterol and low-density lipoprotein-cholesterol, and negatively correlated with aortic distensibility and Sao. CONCLUSIONS: In this study, our results showed that SCH is associated with impaired elasticity of the ascending aorta. Elastic properties of the ascending aorta can be directly evaluated by the reproducibly measurement of the upper wall movements of the ascending aorta by TDI in SCH patients.

Low plasma renin activity and high aldosterone/renin ratio are associated with untreated isolated systolic hypertension

OBJECTIVE

Isolated systolic hypertension (ISH) is generally encountered in elderly patients and there are scarce data regarding the renin-angiotensin-aldosterone system (RAAS) activity in patients with ISH. We aimed to determine the plasma renin activity (PRA), plasma aldosterone levels (PAL) and aldosterone/PRA ratio (PAL/PRA) in patients (age >50 years) with ISH and to compare these values with patients with essential hypertension (EH) as well as subjects with normal blood pressure values (control) who have similar age and cardiovascular risk profile.

METHODS

Consecutively, 42 untreated ISH patients, 30 patients with EH and 29 normal subjects were included in the study. Parameters were presented as median (interquartile range).

RESULTS

There were no significant differences regarding age, gender and other cardiovascular risk factors among groups. As expected, systolic, diastolic blood pressure and pulse pressure values were significantly different among groups. Besides, PRA values were found to be significantly lower in patients with ISH (0.4 [0.2-1.1] ng/ml/h) compared with the EH (0.95 [0.5-2.6] ng/ml/h, p =0.024) and control (1.3 [0.7-2.1] ng/ml/h, p =0.001) groups. Although, PAL were similar among groups, PAL/PRA ratio was significantly higher in ISH group (134.1 [73-224]) compared with those with EH (42.2 [35-84], p <0.001) and the control group (53.3 [30-106], p =0.001). No significant difference was present with respect to PAL/PRA ratio between EH and control groups.

CONCLUSIONS

Our findings suggested that in patients with ISH, despite lower PRA levels, PAL/PRA ratio is significantly higher compared with the patients with EH and subjects with normal blood pressure. Since higher PAL/PRA levels is an indicator of relative aldosterone excess, medications blocking RAAS activity including aldosterone antagonists may have useful cardiovascular consequences in addition to their antihypertensive effects in ISH.

Systemic hemodynamics in relation to glucose tolerance: the Health 2000 Survey

The influence of impaired glucose metabolism--that is, impaired fasting glucose, impaired glucose tolerance (IGT), and type 2 diabetes mellitus diabetes (DM2)--on systemic hemodynamics is largely unknown. Therefore, we investigated the associations of glucose metabolism disturbances with stroke index (SI), cardiac index, systemic vascular resistance index (SVRI), arterial pulse wave velocity (PWV), and heart rate among Finnish adults (N = 389; mean age, 58.3 ± 7.9 years) participating in the Health 2000 Survey. Systemic hemodynamic parameters were measured using the whole-body impedance cardiography device, and an oral glucose tolerance test (OGTT) was performed to evaluate glucose tolerance status. We found a decreasing trend for SI and increasing trends for SVRI and PWV according to the worsening of glucose tolerance (P for trend < .003 for all). In pairwise comparisons, SI was lower in the impaired fasting glucose group (P = .041) and the IGT group (P < .001) as compared with the normal glucose tolerance (NGT) group. Systemic vascular resistance index was higher in the IGT group (P = .045) and the DM2 group (P = .043) than in the NGT group. Subjects with IGT or DM2 had higher arterial PWV (10.7 ± 0.2 m/s, P < .001 and 11.7 ± 0.5 m/s, P = .001, respectively) than subjects with NGT (9.5 ± 0.1 m/s). Moreover, 2-hour glucose in OGTT was an independent determinant of SVRI and PWV (P < .001 and P = .005, respectively) in multivariable linear regression models. In conclusion, the present study demonstrates that glucose intolerance, even without DM2, associates with several adverse changes in systemic hemodynamics and that 2-hour glucose in OGTT is an independent determinant of SVRI and PWV. These findings support the systematic evaluation of glucose tolerance status in the estimation of cardiovascular risk among the middle-aged population.

Usefulness of the resistive index in renal Doppler ultrasonography as an indicator of vascular damage in patients with risks of atherosclerosis

BACKGROUND

Chronic kidney disease (CKD) is caused by various risk factors of cardiovascular disease (CVD). The estimated glomerular filtration rate (eGFR) is commonly used for the evaluation of the renal function in patients with CKD; however, it is difficult to assess the pathogenesis of CKD and predict the renal prognosis accurately using only eGFR. The resistive index (RI) in renal Doppler ultrasonography (RDU) is thought to be a good indicator of renal vascular resistance caused by atherosclerosis. In the present study, we investigated whether RI could be used to evaluate the pathogenesis of renal damage and predict the renal prognosis and investigated the correlation between RI and blood pressure (BP) fluctuations in patients with or without hypertension.

METHODS

The total study population included 194 patients (mean age: 66.2 years), who underwent RDU in our hospital ward between February 2009 and July 2010. We investigated the correlation between RI and multiple clinical parameters, including ambulatory blood pressure monitoring (ABPM).

RESULTS

RI significantly correlated with age, eGFR, diastolic BP, pulse pressure and level of albuminuria. Patients with diabetes mellitus (DM) showed a significantly higher RI than patients without DM, although their eGFR was similar; thus, DM might accelerate renal vascular damage and RI could detect earlier changes of vascular damage proceeding the time eGFR is reduced. Regarding ABPM, patients with a larger morning surge [systolic blood pressure (SBP) in the early morning--lowest SBP during sleep] showed a significantly higher RI.

CONCLUSIONS

The present study indicated that RI might be very useful for the evaluation of very early renal damage more effectively than eGFR and that diurnal BP change might be partly due to the progression of atherosclerotic change in the kidney evaluated by RI.

Pulse pressure, prehypertension, and mortality: the San Antonio heart study

BACKGROUND

Prehypertension increases mortality risk. Pulse pressure is also associated with increased mortality. Nevertheless, the impact of pulse pressure on the relationship between prehypertension and mortality is not known in individuals who are free of diabetes and cardiovascular disease.

METHODS

Cox regression analysis was used to examine mortality risk among 3,632 (97.0%) participants in the San Antonio Heart Study (age range, 25-64 years; mean follow-up, 15.2 years). Results were adjusted for age, sex, ethnicity, education, body mass index (BMI), smoking, and total cholesterol concentration. The Seventh Report of the Joint Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) categories were used for blood pressure staging: normal, <120/80 mm Hg; prehypertension, 120-139/80-89 mm Hg.

RESULTS

Prehypertension prevalence was 31.6% at baseline. There were 218 deaths during the follow-up period. Prehypertension-predicted mortality (all-cause, hazard ratio (HR) 1.49 (1.12-1.99); cardiovascular, HR 1.79 (1.07-3.02)). Relative to normal blood pressure plus pulse pressure in the lower tertile, prehypertension plus pulse pressure in the upper tertile was associated with increased mortality (all-cause, HR 2.14 (1.38-3.32); cardiovascular, HR 2.47 (1.13-5.39)); however, prehypertension plus pulse pressure in the lower tertile was not significantly associated with mortality (all-cause, HR 1.19 (0.52-2.67); cardiovascular, HR 0.43 (0.05-3.40)).

CONCLUSIONS

Prehypertension increases mortality risk (all-cause and cardiovascular) in individuals who are free of diabetes and cardiovascular disease. Nevertheless, this relationship is not evident in individuals with narrow pulse pressure. Therefore, pulse pressure may be a relevant measure of blood pressure for the definition of normal blood pressure.

Effect of intrauterine fetal programming on response to postnatal shaker stress in endothelial nitric oxide knockout mouse model

OBJECTIVE

To determine whether the intrauterine environment affects the postnatal vascular response to stress in a model of fetal programming induced by endothelial nitric oxide synthase deficiency.

STUDY DESIGN

Homozygous nitric oxide synthase knockout and wild-type controls were crossbred to obtain maternally and paternally derived heterozygous offspring. At 14 weeks of age, in vivo blood pressure measurements by telemetry, and in vitro carotid arteries vascular reactivity studies were performed in male offspring after subjecting them to shaker stress.

RESULTS

Maternally derived heterozygous offspring, compared with paternally derived heterozygous offspring, had significantly higher systolic blood pressure, mean arterial blood pressure, and pulse pressure before, as well as after introduction of the shaker stress. The difference in the latter between maternally and paternally derived heterozygous offspring was accentuated after stress. Maternally derived heterozygous offspring also had significantly higher contractile responses to phenylephrine when compared with paternally derived heterozygous offspring, and this was abolished after incubation with L-NAME.

CONCLUSION

The adverse uterine environment affects the postnatal vascular response to stress.

Serum aluminum level correlates with arterial stiffness in haemodialysis patients

BACKGROUND

In addition to pulse wave velocity (PWV), serum aluminum level is predictive of mortality in haemodialysis (HD) patients. This cross-sectional study evaluated the correlations between serum aluminum and brachial-ankle PWV (baPWV).

METHODS

One hundred twenty-seven HD patients (average age 58.46 +/- 9.95 years) were enrolled. Medical data were obtained via chart reviews and hospital database. Associations between biomarker levels and baPWV were analysed by multiple linear regression.

RESULTS

Serum aluminum, high sensitivity C-reactive protein (hsCRP), age, pulse pressure (PP), mean arterial pressure (MAP) and diabetes mellitus (DM) are important correlates of baPWV.

CONCLUSION

Further, hsCRP, PP, age and DM are positively related to arterial stiffness in HD patients.

Transgenerational effect of fetal programming on vascular phenotype and reactivity in endothelial nitric oxide synthase knockout mouse model

OBJECTIVE

The objective of the study was to investigate the transgenerational effect of fetal vascular programming

STUDY DESIGN

Homozygous NOS3 knockout and wild type controls (NOS3+/+WT) were cross-bred to obtain heterozygous offspring that developed in (KO-/-) mothers lacking a functional NOS3 (KOM) vs wild-type control mothers (KOP). The first-generation KOM(+/-) and KOP(+/-) female mice were then bred with WT(+/+) males to obtain a second generation (F2). F2 offspring were genotyped and WT(+/+)-F2 mice were then used for in vivo blood pressure and in vitro vascular reactivity studies.

RESULTS

WT-F2 mice born to KOM mothers (KOM-F2WT) had significantly higher systolic blood pressure, mean arterial pressure, and pulse pressure, compared with WT-F2 born to KOP mothers. Male KOM-F2WT offspring had significantly increased response to phenylephrine (PE), compared with male KOP-F2WT. Male offspring had increased contractile responses to PE when compared with female. Acetylcholine responses were decreased in female KOM-F2WT, compared with female KOP-F2WT, but the difference was not statistically significant

CONCLUSION

Our findings support a transgenerational effect of fetal programming on the vascular phenotype and suggest possible gender specific adaptation.

Relationships Between Vascular Indexes and Atherosclerotic Risk Factors in Patients With Type 2 Diabetes Mellitus

The relationships of cardio-ankle vascular index, (a new indicator of arterial stiffness), common carotid artery intima-media thickness, and ankle-brachial pressure index with atherosclerotic risk factors were compared in patients with type 2 diabetes. There were significant correlations between each pair of the above vascular indexes. Both cardio-ankle vascular index and intima-media thickness showed significant correlations with age, systolic blood pressure, pulse pressure, and serum total cholesterol. Ankle-brachial pressure index showed a significant negative correlation with pulse pressure but not with systolic blood pressure and total cholesterol. Logistic regression analysis showed that cardio-ankle vascular index and intima-media thickness were associated with systolic blood pressure and pulse pressure independently of age. These results suggest that there are significant associations among the 3 vascular indexes and that systolic blood pressure and pulse pressure are major, age-independent determinants of cardio-ankle vascular index and common carotid artery intima-media thickness in patients with diabetes.

Non-traditional cardiovascular risk factors contribute to peripheral arterial disease in patients with type 2 diabetes

OBJECTIVE

This study evaluated the prevalence of peripheral arterial disease (PAD) in type 2 diabetes and its association with traditional and non-traditional cardiovascular (CV) risk factors.

SUBJECTS AND METHODS

In 1610 type 2 diabetics PAD was defined as ankle-brachial pressure index (ABPI)<0.9.

RESULTS

PAD prevalence was 17%, increased with age, diabetes duration, HbA 1c levels, previous CV events. There were no significant differences in the prevalence of traditional CV risk factors between patients with and without PAD. PAD patients had higher levels of fibrinogen (10.88+/-2.32 versus 10.2+/-2.23micromol/L; p<0.0001), uric acid (327.1+/-89.2 versus 315.2+/-83.3micromol/L, p<0.01), pulse pressure (70+/-18 versus 60+/-16mm Hg, p<0.0001), higher rate of microalbuminuria (21.3% versus 13.7%; p<0.05) and lower glomerular filtration rate (GFR, 80.7+/-24 versus 89.9+/-22 ml/min/1.73 m2; p<0.001) than those without. In age-gender-adjusted analysis, smoking (OR 1.5; CI: 1.07-2.2), HbA 1c (OR 1.45; CI: 1.07-2.08), high pulse pressure (OR 2.81; CI: 1.63-4.82), reduced GFR (OR 2.16; CI: 1.4-3.3), microalbuminuria (OR 1.62; CI: 1.11-2.36), high fibrinogen levels (OR 2.03; CI: 1.34-3.07) were associated with PAD. In multivariate analysis age, male sex, smoking, high pulse pressure, low GFR, high fibrinogen levels, previous CV events were independent risk factors for PAD.

CONCLUSIONS

PAD prevalence is high in Type 2 diabetic patients. Non-traditional cardiovascular risk factors may be involved in the development of this complication.

Heritability of arterial stiffness in black and white American youth and young adults

BACKGROUND

Our objectives were to examine the heritability of arterial stiffness measured as pulse-wave velocity (PWV), and its dependence on ethnicity, gender, and blood pressure (BP).

METHODS

As part of the Georgia Cardiovascular Twin Study, we measured aorto-radial (radial) and aorto-dorsalis-pedis (foot) PWV in 702 twins (41% black; 49% male) aged 12 to 30 years (mean age, 17.7 +/- 3.3 years), including monozygotic and dizygotic pairs of the same as well as opposite gender. Ethnicity and gender effects on genetic and environmental contributions to PWV were estimated by genetic model fitting.

RESULTS

Diastolic BP was the most important hemodynamic predictor. The best-fitting models showed no ethnicity or gender differences in estimates of genetic and environmental influence, and indicated substantial heritabilities of 0.43 (95% confidence interval, 0.30 to 0.54) and 0.53 (95% confidence interval, 0.42 to 0.62) for radial and foot PWV, respectively. Over a quarter of these heritabilities (0.19 for radial PWV; 0.14 for foot PWV) could be attributed to genes that also influenced diastolic BP, as based on multivariate models.

CONCLUSIONS

Individual differences in the arterial stiffness of youth and young adults are substantially heritable, and >25% of this heritability is explained by genes that also influence diastolic BP. Heritability estimates do not show any differences between blacks and whites or males and females.

GENETIC INFLUENCES ON THE ARTERIAL WALL

1. Arterial stiffness, which has independent predictive value for cardiovascular events, seems to have a genetic component, largely independent of the influence of blood pressure and other cardiovascular risk factors. 2. In animal models of essential hypertension (stroke-prone spontaneously hypertensive rats and spontaneously hypertensive rats), structural modifications of the arterial wall include an increase in the number of elastin-smooth muscle cell connections and smaller fenestrations of the internal elastic lamina, possibility leading to redistribution of the mechanical load towards elastic materials. These modifications may give rise to mechanisms explaining why changes in arterial wall material accompanying wall hypertrophy in these animals are not associated with an increase in arterial stiffness. 3. In monogenic connective tissue diseases (Marfan, Williams and Ehlers-Danlos syndromes) and the corresponding animal models, precise characterization of the arterial phenotype makes it possible to determine the influence of abnormal, genetically determined, wall components on arterial stiffness. 4. Such studies have highlighted the role of extracellular matrix signalling in the vascular wall and have shown that elastin and collagen not only display elasticity or rigidity, but are also involved in the control of smooth muscle cell function. 5. These data provide strong evidence that arterial stiffness is affected by the amount and density of stiff wall material and the spatial organization of that material.

Association of pulse pressure with carotid atherosclerosis in patients with type 2 diabetes mellitus

Pulse pressure is known to be a potent risk factor for cardiovascular disease. However, it has not been determined whether pulse pressure is associated with cerebrovascular disease in patients with diabetes mellitus. The purpose of the present study was to investigate association of pulse pressure with carotid atherosclerosis in patients with diabetes and to determine whether age and gender affect the association. A cross-sectional study was performed using outpatients with type 2 diabetes. Carotid atherosclerosis and arterial stiffness were evaluated by intima-media thickness of common carotid arteries (IMT) and aortic pulse wave velocity (a-PWV), respectively. The relationship of brachial pulse pressure with IMT was analyzed. Pulse pressure was significantly correlated with age, duration of diabetes, systolic blood pressure, serum sialic acid, a-PWV and IMT. The mean IMT in the highest tertile group of pulse pressure after adjustment for gender was significantly higher than the mean IMT in the lowest tertile group. In analysis using subgroups of gender, a significant correlation between pulse pressure and IMT was shown in women but not in men. In multiple regression analysis, there was a significant correlation between pulse pressure and IMT in women independently of age, body mass index, systolic blood pressure, hemoglobin A1c, atherogenic index, a-PWV, history of therapy for hypertension and history of nephropathy. The results of this study suggest that pulse pressure is a major age-independent predictor of carotid atherosclerosis in female patients with diabetes.

Baseline wander correction in pulse waveforms using wavelet-based cascaded adaptive filter

Pulse diagnosis is a convenient, inexpensive, painless, and non-invasive diagnosis method. Quantifying pulse diagnosis is to acquire and record pulse waveforms by a set of sensor firstly, and then analyze these pulse waveforms. However, respiration and artifact motion during pulse waveform acquisition can introduce baseline wander. It is necessary, therefore, to remove the pulse waveform's baseline wander in order to perform accurate pulse waveform analysis. This paper presents a wavelet-based cascaded adaptive filter (CAF) to remove the baseline wander of pulse waveform. To evaluate the level of baseline wander, we introduce a criterion: energy ratio (ER) of pulse waveform to its baseline wander. If the ER is more than a given threshold, the baseline wander can be removed only by cubic spline estimation; otherwise it must be filtered by, in sequence, discrete Meyer wavelet filter and the cubic spline estimation. Compared with traditional methods such as cubic spline estimation, morphology filter and Linear-phase finite impulse response (FIR) least-squares-error digital filter, the experimental results on 50 simulated and 500 real pulse signals demonstrate the power of CAF filter both in removing baseline wander and in preserving the diagnostic information of pulse waveforms. This CAF filter also can be used to remove the baseline wander of other physiological signals, such as ECG and so on.

Association of pulse pressure with fibrinolysis in patients with type 2 diabetes

INTRODUCTION

Pulse pressure is a potent risk factor for atherosclerotic disease. The purpose of this cross-sectional study was to determine whether pulse pressure is associated with blood coagulation and fibrinolysis in patients with diabetes.

MATERIALS AND METHODS

The relationships between pulse pressure and atherosclerotic risk factors, including blood coagulation and fibrinolysis markers, were investigated in subjects with type 2 diabetes.

RESULTS

Pulse pressure was found to be significantly correlated with blood fibrinolysis markers, such as plasmin-alpha2-antiplasmin complex (PAP) and D-dimer, but not with platelets and blood coagulation markers, such as fibrinogen and thrombin-antithrombin III complex (TAT). The mean pulse pressure levels in the highest tertiles of PAP and D-dimer were significantly higher than those in the lowest tertiles, while the differences in the mean pulse pressure levels among tertile groups of platelets, fibrinogen and TAT were not significant. These relationships of pulse pressure with PAP and D-dimer were not altered by adjustment for age, sex and history of therapy with antihypertensive and/or antithrombotic drugs. On the other hand, neither systolic nor diastolic blood pressure showed significant correlations with PAP, D-dimer, platelets, fibrinogen and TAT. Pulse pressure was also significantly correlated with age, aortic pulse wave velocity, intima-media thickness of the common carotid arteries and serum sialic acid.

CONCLUSIONS

Pulse pressure is associated with blood fibrinolysis as well as atherosclerotic progression in patients with type 2 diabetes. The results of this study suggest that pulse pressure affects atherosclerotic progression through altering hemostatic functions in patients with diabetes.

Systolic, diastolic, and pulse pressures as coronary risk factors in a population with low cholesterol levels: a prospective 10-year evaluation

BACKGROUND

Pulse pressure (PP) has recently been found to be predictive of subsequent cardiovascular, particularly coronary, events in some middle-aged and elderly populations.

HYPOTHESIS

The aim of this prospective population-based study was to evaluate the roles of systolic (SBP), diastolic blood pressure (DBP), and PP in predicting coronary heart disease (CHD) morbidity and mortality in both genders in a population of a wide age span and a setting of low levels of low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol.

METHODS

Of participants in the Turkish Adult Risk Factor Study aged > or = 20 years, those free of CHD at baseline examination in 1990 were followed up for a mean of 9.3 years. Coronary heart disease was diagnosed based on clinical findings and Minnesota coding of resting electrocardiograms (ECGs). In 2,601 men and women (mean age at baseline 41.4 +/- 15 years), deaths from CHD developed in 80 and nonfatal CHD in 158 patients.

RESULTS

In a logistic regression analysis for predictors of composite endpoint of coronary mortality and morbidity, individually. DBP was not significantly and independently associated, while SBP was an independent risk predictor in both genders (relative risk [RR] 1.016). When two of three blood pressure components were entered jointly into the multivariable model, PP had a value inferior to that of SBP among men and women, but was of greater value than DBP in men in predicting both the composite endpoint and death from CHD. Among women, the predictive values of PP and DBP were similar. Within the categories of SBP > or = 120 mmHg in men, PP contributed significantly to the predictive power of SBP in overall CHD risk over and above that supplied by SBP, whereas DBP remained noncontributory.

CONCLUSION

Although inferior to the predictive power of SBP, PP was an important determinant of CHD risk in a population of a diverse age span and a better predictor than DBP in men.

Impact of Type 2 Diabetes Mellitus on Aortic Elastic Properties in Normotensive Diabetes: Doppler Tissue Imaging Study

OBJECTIVES

The stiffening of aorta and other central arteries is a potential risk factor for increased cardiovascular morbidity and mortality. The association of hypertension with type 2 diabetes may obscure the degree to which diabetes alone contributes to impaired arterial function. This study examined whether the presence of type 2 diabetes alone is associated with an impaired aortic mechanical function in patients with or without coronary artery disease (CAD).

METHODS

In all, 154 patients were recruited and assigned to groups A (n = 46, type 2 diabetes with no CAD), B (n = 64, nondiabetic CAD), or C (n = 44, diabetes with CAD) and 20 age- and sex-matched healthy participants were enrolled in a control group. Patients were recruited from those sent for coronary angiography. CAD was excluded for group A. Pulse pressure, aortic strain, and distensibility were calculated from the aortic diameters measured by echocardiography and blood pressure obtained by sphygmomanometer. Aortic wall systolic velocity was measured using pulsed wave Doppler tissue imaging.

RESULTS

Pulse pressure was significantly higher in patient groups A, B, and C in comparison with control group (40.2 +/- 9, 40.1 +/- 11, and 50.2 +/- 13 vs 35.5 +/- 9 mm Hg [P < .01], respectively). The pulsatile change in the aortic diameter and distensibility were less in the patient groups than in the control group (11 +/- 4%, 8 +/- 5%, and 8 +/- 4% vs 17 +/- 9% [P<.001], and 6 +/- 2, 6 +/- 1, and 3 +/- 2 vs 10 cm(2)/dyne/10(3), respectively). In addition, the aortic wall systolic velocity was significantly lower in patient groups compared with control group (6 +/- 2, 6.1 +/- 1, and 5.1 +/- 1 vs 8.5 +/- 1.5 cm/s [P < .01], respectively). Although aortic function parameters were very declined for group C, there was no significant difference between groups A and B that reflected equivalent risk. In diabetic groups A and C, aortic strain, distensibility, and aortic wall systolic velocity showed strong negative correlation with the duration of diabetes (r = -.53, r = -.68, and r = -.56, respectively) and glycosylated hemoglobin (HBA(1)) (r=-.64 [P < .01], r = -.77 [P < .001], and r = -.57 [P < .01], respectively).

CONCLUSION

The increased aortic stiffness that affects patients with type 2 diabetes seems to be an early event that may explain why patients with diabetes have a particularly high risk of developing cardiovascular complications. Poor glycemic control and duration have detrimental effect on aortic elastic properties.

Isolated systolic hypertension: primary care practice patterns in a Nigerian high-risk subpopulation

CONTEXT AND OBJECTIVE

Hypertension management and risk prediction based on diastolic blood pressure may be of little value for older people and people with isolated systolic hyper-tension (ISH). This study investigated primary care practice patterns in ISH management in a Nigerian high-risk subpopulation.

DESIGN AND SETTING

Three-year retrospective cohort review of outpatient medical records at a state primary health care facility in southwestern Nigeria.

METHODS

ISH was defined according to international guidelines. Treatments were graded as relatively non-aggressive, mildly aggressive and moderately aggressive. Data were collected using a data abstraction form and statistically analyzed.

RESULTS

The drug/regimen choice controlled systolic blood pressure (SBP) in only 46.90% of the population after the first visit to the clinic. SBP control among treated patients was significantly inadequate. Group mean SBP was consistently > 150 mmHg in 28.13% of the patients for > or = six weeks after enrollment and for at least two additional visits. Data analysis revealed an increasing tendency to place patients on monotherapy or "no drug treatment" with successive visits to the clinic, even in cases of uncontrolled systolic blood pressure, as well as declining prescription of moderately aggressive combination therapy.

CONCLUSION

Aggressive ISH management needs to be further emphasized at primary care levels, which for many low-income patients may be the first and last orthodox port of call.

Contractile Responses of Aortae from WKY and SHR to Vasoconstrictors

Aortae taken from spontaneously hypertensive (SHR) and Wistar Kyoto (WKY) rats aged 4, 8 and 16 weeks were prepared as rings and used to measure the effects of five vasoconstrictors. The endothelium was removed in order to measure selectively the contractile responses induced by potassium chloride (KCl), phenylephrine (PHE), angiotensin-II (Ang II), endothelin-1 (ET-1) and human urotensin-II (U-II). These responses were assumed to derive from the activation of specific receptors (namely alpha1, AT1, ETA and UT-II) or from depolarization of the smooth muscle fibers by KCl. Specific antagonists prazosin, losartan, BQ-123 and [Orn8]-UII were used at various concentrations for a pharmacological characterization of these latter receptor systems. The primary purpose of the study was to explore mechanisms or factors that may intervene in the development and maintenance of high blood pressure in SHR. Results indicate that isolated aortae of SHR and WKY contain contractile sites (receptors) whose pharmacological profiles (pEC50 for agonists, pA2 for antagonists) are very similar to those of other biological systems and should be considered as typical for the alpha1, AT1, ETA and UT-II receptor types. Aortae taken from SHR 4 (non hypertensive), 8 and 16 weeks old (hypertensive) responded to the vasoconstrictors with reduced maximal contractions compared to those of age-matched WKY. These unexpected reduced responses of aortae, observed with the five vasoconstrictors, may be attributed to a non specific lesions. Maximal contraction of aortae from SHR increased from 4 to 16 weeks for KCI, PHE and U-II, decreased for Ang II, and remained stable for ET-1. There was also an age-dependent increase of maximal contraction induced by U-II in WKY. It is suggested that aortae from SHR undergo early remodelling that leads to reduced contractility in vitro and possibly to vessel rigidity in vivo. The factors involved in this process appear to be of genetic origin since they are present before hypertension: they may contribute to modify aortic compliance and perhaps vascular resistance in hypertensive animals and thus being the cause and not the consequence of high blood pressure.

Blood pressure and progression of chronic kidney disease: Importance of systolic, diastolic, or diurnal variation

Several studies show that systolic blood pressure is an important predictor of renal disease progression, just as it is linked with cardiovascular consequences in hypertension. In contrast, particularly in older patients, diastolic blood pressure was not independently associated with risk of kidney disease progression in the same studies. Pulse pressure has been shown to be equivalent in predicting renal outcomes, but might not have added value after adjusting for systolic blood pressure. Several cross- sectional studies present a strong correlation of ambulatory blood pressure monitoring values with microalbuminuria, compared with office-based blood pressure measurements. Small, prospective studies have shown an association between loss of nocturnal blood pressure decline and outcomes, including microalbuminuria, accelerated kidney disease progression, and mortality.

HYPERTENSION IN HEMODIALYSIS PATIENTS: Hypertension and Survival in Hemodialysis Patients

Hypertension is clearly an independent risk factor for cardiovascular (CV) events and death in the general population, but the relationship between blood pressure (BP) and survival in dialysis patients is less clear. In dialysis populations at lower risk of CV events, BP is directly related to survival, while in those with high risk, it has been difficult to show such an effect. The effects of cardiac disease complicate the relationship between BP and outcome. Retrospective studies of large cohorts, with high prevalence of CV disease, have shown a U-shaped relationship between both systolic and diastolic BP and outcome. These findings probably reflect a high prevalence of cardiac failure and thus high mortality associated with low BP (i.e., a so-called reverse causation). Pulse pressure (high systolic BP and low diastolic BP) predicts outcome in hypertensive dialysis patients. Whether this reflects advanced vessel wall disease or is an independent etiologically significant risk factor is unclear. However, the current uncertainties as to the exact relationship between BP and outcome in dialysis patients do not warrant complacency regarding the prevention and treatment of hypertension.

Hypertension therapy: mixing, matching, and meeting targets

The inappropriate control of hypertension is a public health problem worldwide. It is notable that although there are several causes for this situation, lack of effective pharmacotherapy is not among them. It has long been known that combinations of antihypertensive drugs are highly effective in most patients; the problem is implementing treatment recommendation guidelines into clinical practice with the most effective and best tolerated therapies. The latest guidelines on therapies for hypertension from the World Health Organization/International Society of Hypertension, the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (US), and the European Societies of Hypertension and Cardiology consistently emphasize this need of combination treatments in a large part of the hypertensive patient population. This review focuses on the combination of one of the oldest drugs, thiazide diuretics, with one of the youngest, angiotensin-receptor blockers, and analyzes the available literature regarding potential applications in specific populations. This represents one of the most widely used, rational and effective combination therapies, combining excellent control of blood pressure with unequalled tolerability. In addition, angiotensin-receptor blocker/diuretic combinations may have cardiovascular benefits beyond those from blood pressure lowering itself.

Pulse pressure is associated with age and cardiovascular disease in type 1 diabetes

OBJECTIVE

Type 1 diabetic individuals are thought to have increased arterial stiffness, and are at high risk for cardiovascular disease. However, it is not known whether increased arterial stiffness in type 1 diabetes causes cardiovascular disease. To explore this issue, the present study investigated the association, in type 1 diabetes, of age and pulse pressure, an estimate of arterial stiffness, and the influence of the presence of microvascular complications on this association. In addition, we determined the association of mean arterial pressure and pulse pressure with incident cardiovascular disease.

METHODS

We studied a cohort of 3250 type 1 diabetic individuals of the EURODIAB Prospective Complications Study. Mean age and median follow-up were 33 and 7.4 years. One hundred and sixty-three individuals developed a first manifestation of cardiovascular disease during follow-up. Linear regression analysis was used to determine the association of age with pulse pressure. Relative risks of cardiovascular disease were estimated by Cox regression analyses adjusted for age, sex and mean arterial pressure or pulse pressure.RESULTS In cross-sectional analyses, age was associated with pulse pressure (P < 0.001) and this association was stronger in the presence of micro- or macroalbuminuria or retinopathy than in their absence (interaction for albuminuria, P < 0.001; interaction for retinopathy, P < 0.001). In prospective analyses, both mean arterial pressure and pulse pressure were associated with cardiovascular disease [adjusted relative risks and (95% confidence interval) per 10 mmHg increase were 1.08 (0.94-1.24) and 1.09 (0.98-1.21)].

CONCLUSIONS

This study shows an association of age with pulse pressure in young type 1 diabetic individuals, which is stronger in the presence of microvascular complications. In addition, both mean arterial pressure and pulse pressure are associated with incident cardiovascular disease. These findings support the concept of early vascular ageing in type 1 diabetes, especially in the presence of microvascular complications.