老年患者认知功能障碍与动脉僵硬度关系

目的 探讨老年患者认知功能障碍与动脉僵硬度的关系.方法 选择142例老年患者,以肢体动脉搏动波(PWV)作为评价动脉僵硬度指标,以简易精神状态量表(MMSE)作为认知功能评价指标,MMSE评分总分30分,评分<24分为认知功能障碍.对所有入选病例进行PWV检查及MMSE评分,根据MMSE评分将所有患者分为两组:认知功能正常组93例,认知功能障碍组49例.结果 认知功能障碍组较认知功能正常组PWV明显增高[(13.3±2.4)m/s与(11.8±2.2)m/s,t=3.775,P-0.000].经Logistic回归分析,MMSE评分与PWV呈显著相关.结论 动脉僵硬度增加是老年患者认知功能障碍重要危险因素.     

Arterial stiffness as an independent predictor of longitudinal changes in cognitive function in the older individual

BACKGROUND: Cognitive decline significantly contributes to disability in older individuals. We previously demonstrated cross-sectionally that arterial stiffness [pulse wave velocity (PWV)] was associated with memory loss independently of traditional cardiovascular risk factors and of neuroimaging findings in older individuals without prior stroke. The present study aimed to evaluate PWV as a predictor of longitudinal changes in cognitive function in older individuals reporting memory problems. PARTICIPANTS AND METHODS: We studied 102 older individuals (mean age 79 +/- 6 years; 31 men, 71 women) reporting memory problems. PWV was measured noninvasively by Complior. Traditional cardiovascular risk factor levels were measured. Global cognitive function was measured by the Mini-Mental State Examination (MMSE) (maximum score = 30) at baseline and at follow-up visit. Cerebral computed tomography evaluated the presence of microvascular damage or cortical atrophy. Individuals with prior stroke or atrial fibrillation were excluded. RESULTS: The baseline MMSE was 22.9 +/- 5.5; 61% were hypertensive, 26.8% diabetic, 9.4% smokers, 10.5% taking statins, and 21.1% taking nitrates. The average PWV was 13.5 +/- 2.2 m/s. After a median follow-up of 12 months, the average per-year decline in MMSE was 2.9 points or 12.1%. Multiple regression models showed that PWV independently predicted cognitive decline (model R2 = 0.50). PWV was the single strongest predictor of cognitive decline, explaining 15.2% of the total variance (each 1 m/s increase in PWV was associated with an average 0.74 per-year decrease in MMSE score, P < 0.001). CONCLUSION: In older individuals, arterial stiffness (PWV) is a strong predictor of loss in cognitive function, independent of age, sex, education, and traditional cardiovascular risk factors.     

Arterial stiffness is an independent risk factor for cognitive impairment in the elderly: a pilot study

BACKGROUND: Loss of cognitive function is a common condition in the elderly population. Cognitive impairment is defined as the transitional stage of cognitive decline, between normal aging and early dementia. We tested whether arterial stiffness, evaluated as pulse wave velocity (PWV), is associated with cognitive impairment in older subjects, and whether PWV is increased at a comparable extent in older subjects with cortical or subcortical cerebral lesions when compared with age-matched controls referred for memory deficits. SUBJECTS AND METHODS: Eighty-four subjects (78 +/- 5 years, 30 men and 54 women) referred for memory deficit with no history of stroke or atrial fibrillation were studied. Carotid-femoral PWV was determined non-invasively with Complior. The Mini Mental State Examination was assessed as a measure of global cognitive function. The sum of the score on the Activities of Daily Living and Instrumental Activities of Daily Living scales was used as a measure of personal independency. Based upon brain imaging, subjects were classified as referred for memory deficits with normal brain imaging, or control, with subcortical microvascular lesions or with cortical atrophy. RESULTS: PWV, normalized for mean blood pressure, was inversely correlated with the Mini Mental State Examination (r = -0.26, P < 0.05), even after controlling for education, prevalent cardiovascular (CV) disease, CV risk factors, and medication use (beta coefficient = -0.28, P < 0.01). PWV was also inversely correlated with personal independency (r = -0.36, P < 0.01; beta coefficient = -0.38, P < 0.01, after multiple adjustment). In the presence of no significant differences in age, education, traditional CV risk factor levels, carotid plaques, or prevalence of CV disease, higher PWV values were more frequent in subjects with cortical atrophy than in patients with subcortical microvascular lesions or controls (P < 0.05). CONCLUSIONS: PWV was associated with cognitive impairment and with a greater personal dependency, independently of major modifiable CV risk factors.     

Relation between renal function within the normal range and central and peripheral arterial stiffness in hypertension

Chronic kidney disease is accompanied by increased large-artery stiffness, but the relation between glomerular filtration rate within the reference range and central or peripheral arterial stiffness has been understudied. The link between renal function and arterial stiffness was assessed in 305 patients with never-treated essential hypertension (men: 58%; age: 48+/-11 years, blood pressure: 151/95+/-20/11 mm Hg), free from overt cardiovascular disease and with serum creatinine values <1.4 mg/dL (men) and <1.2 mg/dL (women), who underwent noninvasive aortic and upper-limb pulse wave velocity (PWV) determination. Aortic PWV was strongly related to age (r=0.55; P<0.001), whereas upper-limb PWV had a weaker nonlinear relation with age (beta=1.392; P<0.001 for age; beta=-1.312; P<0.001 for age squared) and a weak relation with aortic PWV (r=0.22; P<0.001). Glomerular filtration rate (GFR), estimated according to the Mayo clinic equation for healthy subjects, was inversely correlated with large-artery stiffness, as assessed by aortic PWV (r=-0.34; P<0.001), and with peripheral artery stiffness, as assessed by upper-limb PWV (r=-0.25; P<0.001). In a multivariate linear regression, aortic PWV was independently predicted by age (beta=0.48; P<0.001), mean arterial pressure (beta=0.14; P=0.013), and GFR (beta=-0.13, P=0.029). Upper-limb PWV was predicted by GFR (beta=-0.24; P<0.001) and mean arterial pressure (beta=0.20; P<0.001). We conclude that, in hypertensive patients with normal renal function, an inverse relationship exists between GFR and stiffness of both central elastic and peripheral muscular arteries. These relations are in part independent from the effect of several confounders, including age, sex, and blood pressure values.     

社区脑卒中高危人群非痴呆性血管性认知功能障碍筛查及相关因素分析

目的了解社区脑卒中高危人群认知功能现状及其相关影响因素。方法采用横断面调查方法对天津市河西区4个社区539例脑卒中高危人群进行筛查,采用简易智能状态检查量表及临床痴呆量表评估认知功能,以是否诊断非痴呆性血管性认知功能障碍(VCIND)分为认知正常组401例和认知障碍组138例,比较分析脑卒中高危人群认知功能障碍与脑卒中危险因素的相关性。结果与认知正常组比较,认知障碍组男性(57.2%vs 46.1%)、年龄≥65岁(60.9%vs 39.7%)、高中以下文化程度(87.0%vs 75.1%)、高脂血症(68.8%vs 55.1%)、脑卒中史(34.1%vs 21.7%)、高同型半胱氨酸血症(63.8%vs 53.6%)认知障碍发生率明显升高(P<0.05,P<0.01);高中以下文化程度是影响脑卒中高危人群认知功能的独立危险因素(OR=0.494,95%CI:0.276⁰.883,P<0.05)。结论社区脑卒中高危人群是VCIND的易患人群,提示及早对具有血管性危险因素的社区人群进行认知功能筛查,对防治VCIND的发生具有重要意义。     

Comparison of vascular stiffness in vascular dementia, Alzheimer dementia and cognitive impairment

Abstract Defining the vascular component(s) of the clinical diagnosis of vascular cognitive impairment (VCI) and vascular dementia (VaD) continues to be problematic. The goal of this study was to determine whether vascular stiffness, measured by pulse wave velocity (PWV), is altered in VaD, to study the utility of PWV in differentiating VaD from Alzheimer dementia (AD) and the relationship between PWV and cognitive function. A qualitative and quantitative structured analysis of the literature was conducted until September 2010, using a search strategy based on the key words: dementia, vascular dementia, dementia of vascular origin, cognitive function and arterial stiffness or pulse wave velocity. Seventeen studies assessed large vessel vascular stiff by PWV and related it to cognitive function or dementia. Six of these studies compared PWV in 154 persons with VaD, 207 with AD and 197 controls without dementia. Mean PWV was significantly (p < 0.0001) higher in VaD compared with controls. Mean PWV was significantly (p = 0.002) higher in VaD compared with AD. Fourteen studies examined the relationship between PWV and cognitive function. The majority of studies (nine of 14) reported a significant correlation between PWV and cognitive function. Four of eight studies that evaluated the relation using univariate analysis reported a significant correlation of PWV with the Mini Mental State Exam (MMSE) or Hasegawa Dementia Scale, and the correlation with MMSE between studies showed a close agreement of correlation coefficients (0.206 to 0.27). In multivariate analysis, adjusted for a wide range of possible confounding factors, the majority or 80% (eight out of 10) studies comprising a population of 6,034 individuals found a significant inverse relationship between PWV and cognitive function. In summary, vascular stiffness is inversely related to cognitive function. Vascular stiffness is greater in VaD compared with AD, suggesting PWV may be useful in identifying VaD.     

Relation of age-related macular degeneration and cognitive impairment in an older population

BACKGROUND: The aetiology of age-related macular degeneration (AMD) and cognitive impairment is poorly understood. A link between cognitive impairment and AMD has been proposed although only a weak association was found in population-based studies. PURPOSE: To assess cross-sectional associations between AMD and cognitive impairment in an older Australian population. METHODS: The Blue Mountains Eye Study examined 3,509 persons aged 49+ years during 1997-2000. AMD lesions were assessed from retinal photographs using the Wisconsin System. Mini-mental state examination (MMSE), demographics, lifestyle factors and medical history were collected at interview. MMSE score was categorised as high-normal (28-30), low-normal (24-27) and impaired (< 24). A modified MMSE excluded five vision related items and was dichotomised as normal (18-22) and impaired (0-17). Logistic regression was used to assess associations after adjusting for age, sex, visual impairment, stroke, current smoking status, hypertension, alcohol consumption and post-high-school qualification. RESULTS: Prevalence rates for late and early AMD were 1.5% (n = 50) and 8.3% (n = 273), respectively. Cognitive impairment was present in 18.0% in persons with late AMD and 8.4% with early AMD, compared to 2.6% in persons without AMD. After multivariate adjustment, late AMD was associated with low normal MMSE (odds ratio (OR): 2.2, 95% confidence interval (CI): 1.1-5.0) and cognitive impairment (OR: 3.7, CI: 1.3-10.6). Using the modified MMSE, the multivariate association between late AMD and cognitive impairment remained (OR: 2.2, CI: 1.0-5.0). No significant association was found between cognitive impairment and early AMD. CONCLUSIONS: We found a significant, cross-sectional association between late AMD and cognitive impairment in a sample of older Australians that appeared to be independent of visual impairment. The association was weaker but remained significant after excluding vision-related items from the MMSE.     

Arterial damage and cognitive decline in chronic kidney disease patients

In the general population aortic stiffening, assessed by carotid femoral pulse wave velocity (cf‐PWV), is associated with cognitive dysfunction (CO/DY). Data in chronic kidney disease (CKD) are limited. This study tests the hypothesis that large artery stiffness and microvascular damage in CKD patients are related to the damage of brain microcirculation reflected by impaired cognitive function. A cross‐sectional study enrolled 151 patients (mean age 58.4 years; 64.5% males; 44 patients with CKD stage 1; 47 with stage 2; 25 with stage 3; and 35 with stage 4). Cognitive impairment, assessed by the Mini Mental State Examination (MMSE), the Clock – drawing test (Clock‐test), and the Instrumental Activity of Daily Living (IADL), was considered as primary outcome. We measured systolic and pulse pressures at the brachial and aortic sites and cf‐PWV. Our patients revealed a significant linear deterioration in all the domains of cognitive function according to CKD stages. High values of cf‐PWV (P = 0.029) and aortic pulse pressure (aPP) (P < 0.026) were independent determinants of cognitive decline assessed by the MMSE. The present trial supports the hypothesis of an interaction between the kidney, large artery damage, central pressure pulsatility, and the injury of brain microcirculation. In clinical practice, cf‐PWV and aPP measurements may help to predict cognitive decline. Whether the reduction in aortic stiffness following an aggressive treatment translates into improved cognitive outcomes remains to be determined.     

Cognitive impairment decreases postural control during dual tasks in geriatric patients with a history of severe falls

OBJECTIVES: To investigate the influence of dual tasks, cognitive strategies, and fear of falling on postural control in geriatric patients with or without cognitive impairment and with a history of falls resulting in injury. DESIGN: Experimental three-group design. SETTING: Geriatric hospital. PARTICIPANTS: Twenty young healthy adults (mean age+/-standard deviation=25.4+/-4.4), 20 geriatric patients with a history of severe falls without cognitive impairment (mean age=82.6+/-5.5, mean Mini-Mental State Examination (MMSE) score=27.8+/-2.0) and 20 geriatric patients with a history of severe falls and cognitive impairment (mean age=83.2+/-5.5, mean MMSE=19.2+/-3.3). MEASUREMENTS: Motor performance: sway area and lateral and anterior-posterior sway angles. Cognition: semiautomated calculation steps (serial 2 forward) and nonautomated calculation derived from MMSE (serial 7 retro). Motor and cognitive performances were examined as single and dual tasks. Strategy decision, fear of falling, and subjective perception of motor and cognitive performance were assessed as covariates for dual-task performances. RESULTS: Motor performance decreased significantly during all dual tasks in geriatric patients with cognitive impairment and a history of falls resulting in injury. Cognitive performance was different depending on the task and group. Choice of cognitive strategies or fear of falling did not influence the dual-task performances. CONCLUSION: Even simple additional tasks substantially decrease postural stability due to attention-related cognitive deficits in cognitively impaired geriatric patients with a history of severe falls. The findings may help to explain the increased incidence and severity of falls in geriatric patients with cognitive impairment and a history of falls resulting in injury.     

Increased iron and oxidative stress are separately related to cognitive decline in elderly

Aim: The aim of this study is to examine the relation between body iron, oxidative stress and cognitive function in elderly. Methods: Eighty‐seven elderly residents from nursing homes were the subjects of our study. Cognitive status was screened by the Mini‐Mental State Examination (MMSE). Of the 87 eligible subjects, 46 patients who obtained 24 or fewer points on the MMSE scale were considered as subjects with cognitive dysfunction. The control group consisted of 41 subjects who obtained more than 24 points on the MMSE. Routine biochemical analyses, parameters of iron metabolism, malondialdehyde (MDA) and glutathione peroxidase (GSH‐Px) were determined in all subjects. Results: There were statistically significant increases in serum iron, transferrin saturation, ferritin and MDA levels; whereas there was a statistically significant decrease in serum GSH‐Px enzyme activity and serum sodium levels in subjects with cognitive dysfunction. A significant negative correlation was found between serum iron, transferrin saturation, ferritin and MMSE score. There was a negative correlation between MMSE score and serum MDA; however, a positive significant correlation was found between MMSE score and both GSH‐Px enzyme activity and serum sodium. Conclusion: Our study provides evidence of increased markers of iron deposition and oxidative stress in patients with cognitive dysfunction. It seems likely that these markers negatively affect the MMSE score. Interestingly, we did not find any correlation between the markers of iron deposition and oxidative stress. Future studies will be required to demonstrate whether diminishing iron and oxidative stress will enhance MMSE score and thereby ameliorate cognitive impairment. Geriatr Gerontol Int 2011; 11: 504–509.     

Isolated systolic hypertension is characterized by increased aortic stiffness and endothelial dysfunction

Isolated systolic hypertension is associated with increased cardiovascular risk. It is thought to result from large artery stiffening, which is determined by structural components within the vasculature but also by functional factors including NO and endothelin-1. We hypothesized that endothelial dysfunction would account for increased arterial stiffness in patients with isolated systolic hypertension. The aim of this study was to investigate the relationship between endothelial function and arterial stiffness in these patients along with control subjects. We studied 113 subjects: 35 patients with isolated systolic hypertension (mean age+/-SD: 68+/-6 years), 30 age-matched control subjects (65+/-5 years), and 48 young control subjects (37+/-9 years). Aortic pulse wave velocity (PWV) was derived by sequential carotid/femoral waveform recordings. Conduit artery endothelial function was determined by flow-mediated dilatation. Aortic PWV was higher (9.65+/-2.56 m/s versus 8.26+/-0.85 m/s; P=0.009), and flow-mediated dilatation was lower (2.67+/-1.64% versus 4.79+/-3.1%; P=0.03) in patients with isolated systolic hypertension compared with age-matched control subjects. Similarly, aortic PWV was also higher, and flow-mediated dilatation lower, in older versus young control subjects (8.26+/-0.85 m/s versus 7.09+/-1.01 m/s and 4.79+/-3.1% versus 6.94+/-2.7%; P=0.004 for both). Overall, aortic PWV correlated inversely with flow-mediated dilatation (r=-0.3; P=0.001), which remained significant after adjustment for confounding factors (P=0.01). Patients with isolated systolic hypertension have higher aortic PWV and decreased endothelial function compared with age-matched control subjects. Our results suggest that endothelial function contributes significantly to increased arterial stiffness in patients with isolated systolic hypertension and with age.     

Vascular dysfunction and autonomic neuropathy in Type 2 diabetes.

AIMS: To test the hypothesis that arterial dysfunction in Type 2 diabetes is related to autonomic neuropathy. METHODS: Arterial function and autonomic neuropathy were assessed over two consecutive days in 45 Type 2 diabetic and control subjects. Systemic arterial compliance (SAC), arterial stiffness (pulse-wave velocity, PWV) and carotid intima thickness (IMT) were assessed; these markers reflect early vascular disease and predict clinical vascular events. Autonomic neuropathy was assessed using heart rate variability with continuous ECG recording during various breathing and postural manoeuvres and an overall autonomic score was generated. Fasting metabolic parameters including glucose, insulin, HbA(1c) and lipid profile were measured. RESULTS: Autonomic neuropathy tests were all repeatable in diabetic subjects. Compared with controls, diabetic subjects had arterial dysfunction with increased PWV (P = 0.009), IMT (P < 0.001) and reduced SAC (P = 0.053). After adjustment for age, central PWV correlated with fasting insulin (r(2) = 0.45, P < 0.05) and autonomic score (r(2) = 0.44, P < 0.05), peripheral PWV correlated with autonomic score (r(2) = 0.51, P < 0.005) and IMT correlated with fasting insulin (r(2) = 0.5, P < 0.005). The presence of autonomic neuropathy correlated with fasting insulin (P = 0.015), but not age, duration diabetes, lipids or blood pressure. CONCLUSION: Using repeatable measures of autonomic neuropathy and vascular function in Type 2 diabetic subjects, we have demonstrated associations between autonomic neuropathy, vascular dysfunction and hyperinsulinaemia. This may help to explain the excess cardiovascular mortality seen in diabetic subjects with autonomic neuropathy.     

A1166C polymorphism of angiotensin II type 1 receptor, blood pressure and arterial stiffness in hypertension

OBJECTIVE: To study the association of the AC polymorphism of angiotensin II type 1 receptor gene (AGTR1) with blood pressure and central arterial stiffness in a population of hypertensive patients referred to hospital for further work-up. METHODS: One hundred and eighty-five patients, referred to our department from April 1998 to February 2002, were included. Blood pressure was measured by conventional and 24-h ambulatory methods, and arterial stiffness by carotid-femoral pulse wave velocity (PWV) determination. Genotyping for the AGTR1 AC polymorphism was performed by polymerase chain reaction. RESULTS: AGTR1 AC polymorphism was not associated with systolic or diastolic blood pressure, measured either by conventional (P=0.89 and P=0.67, respectively) or by 24-h ambulatory (P=0.57 and P=0.56, respectively) methods. Conversely, this polymorphism was significantly associated with PWV (P=0.006) and had a dose-allele effect, PWV increasing with the number of A alleles (10.6 +/- 2.4 m/s in CC, 11.9 +/- 2.5 m/s in AC and 12.7 +/- 2.7 m/s in AA patients, P=0.002). Multiple regression analysis showed that AC polymorphism was still independently associated with PWV (P=0.01) and was the third most important determinant of PWV after age (P <0.0001) and 24-h mean blood pressure (P <0.0001). CONCLUSION: In our study population, central arterial stiffness assessed by PWV was significantly and independently associated with the AC polymorphism, increased PWV being associated with the presence of the A allele. Further investigations are required for identification of the underlying mechanisms.     

The T-allele of the C825T polymorphism is associated with higher arterial stiffness in young healthy males

Arterial stiffening is the major cause of increasing systolic blood pressure in arterial hypertension. Increased arterial stiffness is one major mechanism responsible for morbidity and mortality in hypertension. A C825T polymorphism was identified in the gene encoding the G-protein beta3 subunit (GNB3), and an association of the T-allele with hypertension was demonstrated in several studies. In order to identify a pathogenetic link between hypertension and arterial stiffness, we compared two indices of arterial stiffness, pulse wave velocity (PWV) and augmentation index, in young, healthy men with and without the 825T-allele under resting conditions. PWV was determined from pressure tracing over carotid and femoral arteries in 99 subjects (CC: n=43; CT&TT: n=56). Augmentation index was derived in 72 subjects (CC: n=30; CT&TT: n=42) by pulse wave analysis using radial applanation tonometry. Carriers of the 825T-allele exhibited a significantly higher PWV compared to subjects with the CC genotype (6.0+/-0.1 m/s (TC&TT) vs 5.7+/-0.1 m/s (CC); P=0.0251). There was also a significant difference (P = 0.0448) in augmentation index between carriers of the T-allele (CT&TT: 3.4+/-2.9%) and controls with the CC -genotype (-5.0+/-4.1 %). There was no difference in any other anthropometric (age, height, weight, body mass index) or haemodynamic (heart rate, peripheral and central blood pressure). In summary, the C825T polymorphism is associated with higher arterial stiffness in young, healthy males. Arterial stiffening may pathogenetically contribute to the development of hypertension in carriers of the T-allele.     

Arterial blood pressure and arterial stiffness in adolescents are related to gestational age

BACKGROUND: Recent studies show that low birth weight (LBW) infants are at risk of increased arterial blood pressure (BP) in adulthood. Previous work from our centre and others suggests that arterial stiffness (AS) is increased in such patients. However, the respective roles of preterm birth and of intrauterine growth restriction (IUGR) are unclear. AIM: To characterize AS and BP in adolescents who were: born at term with an appropriate birth weight for gestational age (GA) (group 1, n=41); born preterm with an appropriate birth weight for GA (group 2, n=25); born at term and small for GA (group 3, n=24). PATIENTS AND METHODS: Systemic BP was measured with an automated oscillometric device. AS was assessed by measuring pulse wave velocity (PWV) between carotid and radial arteries. RESULTS: 90 adolescents were studied at a mean (SD) age of 13.9 (1.2) years. Subjects from group 2 were born with a 33.6 (1.5) GA. Systolic BP, mean BP, and PWV were significantly increased in group 2 subjects in comparison to both group 1 (123 +/- 11 vs. 117 +/- 11 mmHg, p = 0.04; 88 +/- 7 vs. 83 +/- 7 mmHg, p = 0.03; 7.7 +/- 1.0 vs. 7.0 +/- 0.9 m/s, p = 0.02 respectively) and to group 3 (114 +/- 15 mmHg, p = 0.03: 79 +/- 8 mmHg, p = 0.001; 6.8 +/- 0.9 m/s, p = 0.005 respectively) subjects. Systolic BP, mean BP, and PWV were similar in group 1 and group 3 subjects. CONCLUSION: BP and AS are increased during adolescence in subjects born with a LBW due to preterm birth, while they are not altered in subjects when LBW is related to IUGR. It may be speculated that such changes predispose to long term hypertension and that preterm birth is involved in the early programming of arterial diseases in adulthood.     

Arterial stiffness is related to insulin resistance in nondiabetic hypertensive older adults

Hypertension, diabetes, obesity, and aging are associated with increased arterial stiffness. Both insulin resistance and hyperglycemia may contribute to the development of arterial stiffness. Older nondiabetic hypertensive adults were recruited to test the following hypotheses: (1) insulin resistance is associated with arterial stiffness, and (2) this relationship is independent of glucose tolerance status. Aortic pulse wave velocity (PWV), pulse pressure (PP), insulin sensitivity index (S(I), measured by insulin-assisted frequently sampled iv glucose test), glucose tolerance status, and abdominal fat mass were assessed in 37 older (23 male, 14 female, mean age 69.4 +/- 5.9 yr), nondiabetic, hypertensive adults after a 4-wk antihypertensive medication withdrawal. Both PWV and PP were negatively correlated with S(I) (r = -0.49, P = 0.002, and r = -0.38, P = 0.02, respectively). The mean PWV and PP in those with normal glucose tolerance were not significantly different from those with impaired glucose tolerance (9.8 +/- 2.4 vs. 10.0 +/- 3.1 m/sec, P = 0.79 and 71 +/- 17 vs. 72 +/- 18 mm Hg, P = 0.80, respectively). In multiple regression analysis, PWV and PP remained independently correlated with S(I) (P < 0.05) after adjusting for age, gender, fasting glucose, glucose tolerance status, body mass index, or abdominal fat mass. These results suggest that in hypertensive, nondiabetic, older adults, insulin resistance is associated with arterial stiffness independent of glucose tolerance status.     

Effect of beta-adrenergic stimulation on pulse wave velocity in black and white subjects

BACKGROUND: Reduced beta-adrenergic sensitivity has been reported in black subjects. We hypothesized that beta-adrenergic stimulation by isoproterenol would affect pulse wave velocity (PWV), a marker of arterial stiffness, differently in black and white subjects. METHODS: Healthy normotensive black subjects (n = 21) matched for age, gender, height and body mass index with healthy normotensive white subjects (n = 20), participated in a randomized, double-blind, placebo-controlled cross-over study. The PWV was determined using an automated device at baseline and after 30 min of an equal volume infusion of isoproterenol (8 mug/kg per min) or placebo (dextrose 5%), separated by a washout period of 25 min. RESULTS: At baseline, heart rate (HR), systolic and diastolic blood pressure (SBP, DBP) and PWV were comparable in black and in white subjects. Placebo had no significant effect on haemodynamic variables. Isoproterenol increased HR, SBP and pulse pressure and decreased DBP with a comparable magnitude in both groups. Compared with placebo, isoproterenol decreased carotid-femoral PWV in white (from 5.9 +/- 1.2 to 5.7 +/- 1.1 m/s, means +/- SD, P = 0.05), but not in black subjects (from 6.2 +/- 1.3 to 6.6 +/- 1.7 m/s, P = 0.1). The difference in response between black and white subjects was significant (P = 0.04). Isoproterenol decreased carotid-radial PWV only significantly in white subjects. CONCLUSION: These results are compatible with the hypothesis of an altered beta-adrenergic sensitivity, which is expressed by a blunted effect of isoproterenol on arterial stiffness in black subjects.     

Differences in arterial compliance, microvascular function and venous capacitance between patients with heart failure and either preserved or reduced left ventricular systolic function

BACKGROUND: Up to 50% of patients with the clinical syndrome of heart failure have preserved left ventricular systolic function (HF-PSF). These patients may have abnormalities of ventriculo-vascular coupling, due to increased vascular and ventricular stiffness. METHODS: We compared arterial compliance, microvascular vasodilator function and venous capacitance (VC) in 3 groups of patients (n=12 each) matched for the presence of coronary heart disease: 1) HF and preserved systolic function (HF-PSF), 2) HF and reduced systolic function (HF-RSF) and 3) controls (no HF, PSF). Arterial compliance was assessed by measuring aortic pulse wave velocity (PWV) with applanation tonometry. Cutaneous microvascular function was assessed using Laser Doppler imaging (LDI) coupled with iontophoresis of endothelium-dependent (acetylcholine) and -independent (sodium nitroprusside) vasodilators. VC was measured using venous occlusion plethysmography. RESULTS: PWV was significantly higher in HF-PSF subjects than in both HF-RSF and control groups (10.7 [1.1], 8.9 [1.7] and 8.6 [2.1] m/s respectively, p<0.05). Acetylcholine and nitroprusside induced vasodilatation were equally impaired in HF-PSF and HF-RSF, as compared to controls (p<0.01). VC was higher in HF-RSF subjects compared with HF-PSF subjects (1.75 [0.41], 1.34 [0.34] ml/100 ml forearm vol. respectively, p<0.05). CONCLUSIONS: These findings are consistent with a more marked increase in vascular stiffness in HF-PSF than in HF-RSF and suggest that arterial stiffness, dynamic vasodilator function and venous abnormalities may be implicated in the complex pathophysiology of HF-PSF.     

Relationship between arterial stiffness and the risk of coronary artery disease in subjects with and without metabolic syndrome.

We examined the influence of metabolic syndrome (MetS) on the relationship between arterial stiffness and the risk of coronary artery disease (CAD). In 396 subjects (age, 63+/-11 years) who underwent coronary angiography, multiple linear regression analysis demonstrated that the brachial-ankle pulse wave velocity (PWV), but not the presence of MetS, was a significant determinant of the number of diseased coronary arteries (beta=0.10, p<0.05), even though both the brachial-ankle PWV and the number of diseased coronary arteries were higher in subjects with MetS (n=100) than in those without MetS (n=296). However, in subjects with MetS, multiple linear regression analysis demonstrated that the brachial-ankle PWV was not a significant determinant of the number of diseased coronary arteries. The brachial-ankle PWV values were classified into tertile ranges in subjects with and without MetS. The number of diseased coronary arteries increased significantly with an increase in the tertile number of the brachial-ankle PWV in the subjects without MetS (tertile 1=1.00+/-0.86, tertile 2=1.29+/-1.01, and tertile 3=1.45+/-1.05), but not in those with MetS. In conclusion, the results of this study suggest that arterial stiffness is a marker of the risk of CAD in subjects without MetS, whereas in subjects with MetS, the syndrome may directly produce clinically significant atherosclerotic stenosis of the coronary arteries independent of its significant promotion of the development of coronary atherosclerosis via an increase of arterial stiffness.     

Determinants of arterial stiffness in an apparently healthy population over 60 years

Arterial stiffness assessed by the pulse wave velocity (PWV), a non-invasive and reproducible method, predicts cardiovascular morbidity and mortality. The main determinants of arterial stiffness are well established in younger and middle-aged populations, but much less in the elderly. The aim of this study was to describe the determinants of arterial stiffness in elderly apparently healthy subjects. The study included 221 voluntary subjects born before 1944 (mean age 67.4+/-5.0 years), who had a standard health check-up at the 'Centre de Médecine Préventive' of Nancy. Arterial stiffness was evaluated by measuring the carotid-femoral PWV with the PulsePen automatic device. Clinical and biological parameters were evaluated at the same day. Measurements were valid and analysed in 207 subjects (94 women). Mean PWV was 9.39+/-2.64 m/s. Men showed higher PWV values than women (9.99+/-2.56 vs 8.66+/-2.56, P<0.001). In univariate analysis, PWV was correlated with age (r=0.26, P<0.001) and mean arterial pressure (MAP) (r=0.40, P<0.001), and these relationships were similar in men and women. Subjects with hypertension (P<0.001), diabetes mellitus (P<0.001) and obesity (P<0.01) had higher values of PWV. In multiple regression analysis, PWV correlated positively and independently with age, male gender, MAP and diabetes mellitus. In conclusion, in an apparently healthy elderly population, the main determinants of arterial stiffness are the age, MAP, diabetes and gender. Our study also shows that the gender-related differences in arterial stiffness observed in middle-aged subjects are maintained in the elderly.