Ultrasonic evaluation of common carotid intima-media thickness (IMT)--influence of local plaque on the relationship between IMT and age

Vascular Aging: Assessment and Intervention

Vascular aging represents a collection of structural and functional changes in a blood vessel with advancing age, including increased stiffness, vascular wall remodeling, loss of angiogenic ability, and endothelium-dependent vasodilation dysfunction. These age-related alterations may occur earlier in those who are at risk for or have cardiovascular diseases, therefore, are defined as early or premature vascular aging. Vascular aging contributes independently to cardio-cerebral vascular diseases (CCVDs). Thus, early diagnosis and interventions targeting vascular aging are of paramount importance in the delay or prevention of CCVDs. Here, we review the direct assessment of vascular aging by examining parameters that reflect changes in structure, function, or their compliance with age including arterial wall thickness and lumen diameter, endothelium-dependent vasodilation, arterial stiffness as well as indirect assessment through pathological studies of biomarkers including endothelial progenitor cell, lymphocytic telomeres, advanced glycation end-products, and C-reactive protein. Further, we evaluate how different types of interventions including lifestyle mediation, such as caloric restriction and salt intake, and treatments for hypertension, diabetes, and hyperlipidemia affect age-related vascular changes. As a single parameter or intervention targets only a certain vascular physiological change, it is recommended to use multiple parameters to evaluate and design intervention approaches accordingly to prevent systemic vascular aging in clinical practices or population-based studies.

Aromatase inhibitor use is a risk factor of carotid plaque presence in endocrine-responsive breast cancer patients

BACKGROUND/AIMS

The aromatase inhibitors (AIs) are well known anti-hormonal therapy in endocrine-responsive breast cancer patients. It can lead to dyslipidemia and be the risk factor of cardiovascular disease due to low estrogen level. However, some recent studies comparing AIs with placebo have shown controversial results. The aim of this study was to investigate lipid profiles, measurement of carotid intima-media thickness (IMT) and the presence of plaque among endocrine-responsive breast cancer treated with AIs compared to ones that were not treated with AIs.

METHODS

A total of 85 postmenopausal women, who underwent breast cancer surgery during the age of 50 to 64 without history of statin use were included. There were 42 patients who were treated with AIs over 1 year (group 1) and 43 patients without AIs use (group 2). Serum total cholesterol, high density lipoprotein cholesterol, triglycerides, fasting blood glucose, carotid IMT, and presence of plaque were assessed.

RESULTS

The baseline characteristics were similar between two groups and there was no significant difference in carotid IMT irrespective of AIs administration. However, ultrasonographic evaluation of carotid artery revealed that the presence of plaque in AI users was significantly higher than in non-AI users (66.7% vs. 41.9%, p = 0.02; odds ratio, 4.21 in adjusted model; p = 0.01). History of diabetes was also the significant risk factor for the plaque formation.

CONCLUSION

There was no significant difference in lipid profile itself between two groups, but more importantly the presence of the plaque was much higher indicating possible detrimental effect of AI on cardiovascular system.

Prognostic role of carotid intima-media thickness in off-pump coronary artery bypass surgery

Carotid intima-media thickness (IMT) is a well-known predictor of adverse outcomes in the ischemic heart disease patients; however, evidence is lacking in patients undergoing off-pump coronary artery bypass surgery (OPCAB). Data from 407 patients who underwent OPCAB between April 2013 and August 2016 were retrospectively reviewed. A composite of cardiovascular morbidity endpoints was defined as the presence of stroke, acute myocardial infarction, new cardiac arrhythmia (newly developed atrial fibrillation, atrial flutter, or atrioventricular block), cardiovascular death, or cerebrovascular death within 30 days after surgery. Increased carotid IMT was defined as ≥0.9 mm on one or both sides. The incidence of a composite of cardiovascular morbidity endpoints was 24.0% in the normal IMT group (n = 221) and 34.4% in the increased IMT group (n = 186) (p = 0.021). Multivariable analysis revealed increased IMT (odds ratio 1.719, 95% confidence interval 1.108 to 2.666, p = 0.016) and preoperative renal replacement therapy (odds ratio 4.264, 95% confidence interval 1.679 to 10.829, p = 0.002) as independent predictors of a composite of cardiovascular morbidity endpoints. In patients undergoing OPCAB, preoperative assessment of carotid IMT may help predicting the development of a postoperative composite of cardiovascular morbidity endpoints.

Mineral metabolism factors predict accelerated progression of common carotid intima-media thickness in chronic kidney disease: the NEFRONA study

Background

The leading cause of premature death in chronic kidney disease (CKD) is cardiovascular disease (CVD), but risk assessment in renal patients is challenging. The aim of the study was to analyse the factors that predict accelerated progression of common carotid intima-media thickness (CCIMT) in a CKD cohort after 2 years of follow-up (2010-12).

Methods

The study included 1152 patients from the NEFRONA cohort with CKD stages 3-5D and without a clinical history of CVD. CCIMT was measured at the far wall on both common carotids. CCIMT progression was defined as the change between CCIMT at baseline and at 24 months for each side, averaged and normalized as change per year. Accelerated progressors were defined as those with a CCIMT change ≥75th percentile.

Results

The median CCIMT progression rate was 0.0125 mm/year, without significant differences between CKD stages. The cut-off value for defining accelerated progression was 0.0425 mm/year. After adjustment, age was a common factor among all CKD stages. Traditional cardiovascular risk factors, such as diabetes and systolic blood pressure, were predictors of progression in CKD stages 4-5, whereas high-density lipoprotein and low-density lipoprotein cholesterol predicted progression in women in stage 3. Mineral metabolism factors predicting accelerated progression were serum phosphorus in stages 3 and 5D; low 25-hydroxyvitamin D and parathyroid hormone levels >110 pg/mL in stages 4-5 and intact parathyroid hormone levels out of the recommended range in stage 5D.

Conclusions

Mineral metabolism parameters might predict accelerated CCIMT progression from early CKD stages.

Carotid Artery Plaques, Carotid Intima-Media Thickness, and Risk of Cardiovascular Events and All-Cause Death in Older Adults: A 5-Year Prospective, Community-Based Study

We assessed the effect of asymptomatic carotid atherosclerosis (CAS) on the development of cardiovascular diseases (CVDs) in a community-based population aged ≥55 years in China. A total of 1376 residents underwent CAS assessment by ultrasonography in July 2009. New CVD events, including stroke and coronary heart events, were collected at the follow-up survey at the end of 2014. After adjusting for baseline demographic characteristics and traditional CVD risk factors, the risk of CVD in patients with minimal CAS (mean common carotid artery intima-media thickness [CCA-IMT] ≥1 mm and no plaques), nonstenotic plaques (carotid stenosis <50%), and stenotic plaques (carotid stenosis ≥50%) was 0.8 (hazard ratio [HR]: 0.75, 95% confidence interval [CI]: 0.33-1.69), 2.0 (HR: 2.01, 95% CI: 1.24-3.25), and 3.1 (HR: 3.05, 95% CI: 1.62-5.74) times greater, respectively, than that of patients without CAS (CCA-IMT <1 mm and no plaques). Our findings provide direct evidence of the independent predictive value of the severity of asymptomatic CAS for the development of CVD in older Chinese adults.

Intima-media thickness: indicator of cardiovascular risk and measure of the extent of atherosclerosis

The measurement of intima-media thickness (IMT) of large superficial arteries, especially the carotid, using high-resolution B-mode ultrasonography has emerged as one of the methods of choice for determining the anatomic extent of atherosclerosis and for assessing cardiovascular risk. IMT measurement obtained by ultrasonography correlates very well with pathohistologic measurements and the reproducibility of this technique is good. Population studies have shown a strong correlation between carotid IMT and several cardiovascular risk factors, and it has also been found to be associated with the extent of atherosclerosis and end-organ damage of high-risk patients. Therefore, increased carotid IMT is a measure of athero-sclerotic burden and a predictor of subsequent events. Because of its quantitative value, carotid IMT measurement is more and more frequently used in clinical trials to test the effects of different preventive measures, including drugs. More recently, there has been interest in the clinical use of this technique for detecting preclinical (asymptomatic) atherosclerosis and for identifying subjects at high risk. Measurement of carotid IMT could influence a clinician to intervene with medication and to use more aggressive treatment of risk factors in primary prevention, and in patients with atherosclerotic disease in whom there is evidence of progression and extension of atherosclerotic disease. For more extensive use of this method in clinical practice a consensus concerning the standardization of methods of measurement and precise definition of threshold between normal and pathologic IMT value is urgently needed.

Major dietary patterns and carotid intima-media thickness in Bangladesh

OBJECTIVE

Carotid intima-media thickness (IMT) is a validated surrogate marker of preclinical atherosclerosis and is predictive of cardiovascular morbidity and mortality. Research on the association between IMT and diet, however, is lacking, especially in low-income countries or low-BMI populations.

DESIGN

Cross-sectional analysis. Dietary intakes were measured using a validated, thirty-nine-item FFQ at baseline cohort recruitment. IMT measurements were obtained from 2010-2011.

SETTING

Rural Bangladesh.

SUBJECTS

Participants (n 1149) randomly selected from the Health Effects of Arsenic Longitudinal Study, an ongoing, population-based, prospective cohort study established in 2000. Average age at IMT measurement was 45·5 years.

RESULTS

Principal component analysis of reported food items yielded a 'balanced' diet, an 'animal protein' diet and a 'gourd and root vegetable' diet. We observed a positive association between the gourd/root vegetable diet and IMT, as each 1 sd increase in pattern adherence was related to a difference of 7·74 (95 % CI 2·86, 12·62) μm in IMT (P<0·01), controlling for age, sex, total energy intake, smoking status, BMI, systolic blood pressure and diabetes mellitus diagnoses. The balanced pattern was associated with lower IMT (-4·95 (95 % CI -9·78, -0·11) μm for each 1sd increase of adherence; P=0·045).

CONCLUSIONS

A gourd/root vegetable diet in this Bangladeshi population positively correlated with carotid IMT, while a balanced diet was associated with decreased IMT.

Short leukocyte telomere length predicts incidence and progression of carotid atherosclerosis in American Indians: the Strong Heart Family Study

Short leukocyte telomere length (LTL) has been associated with atherosclerosis in cross-sectional studies, but the prospective relationship between telomere shortening and risk of developing carotid atherosclerosis has not been well-established. This study examines whether LTL at baseline predicts incidence and progression of carotid atherosclerosis in American Indians in the Strong Heart Study. The analysis included 2,819 participants who were free of overt cardiovascular disease at baseline (2001-2003) and were followed through the end of 2006-2009 (average 5.5-yr follow-up). Discrete atherosclerotic plaque was defined as focal protrusion with an arterial wall thickness ≥50% the surrounding wall. Carotid progression was defined as having a higher plaque score at the end of study follow-up compared to baseline. Associations of LTL with incidence and progression of carotid plaque were examined using Cox proportional hazard regression, adjusting for standard coronary risk factors. Compared to participants in the highest LTL tertile, those in the lowest tertile had significantly elevated risk for both incident plaque (HR, 1.49; 95% CI, 1.09–2.03) and plaque progression (HR, 1.61; 95% CI, 1.26–2.07). Our results provide initial evidence for a potential prognostic utility of LTL in risk prediction for atherosclerosis.

Association of residual plasma viremia and intima-media thickness in antiretroviral-treated patients with controlled human immunodeficiency virus infection

Background

While residual plasma viremia is commonly observed in HIV-infected patients undergoing antiretroviral treatment (ART), little is known about its subclinical consequences.

Methods

This cross-sectional study included 47 male, never-smoking, non-diabetic patients with ≥4 years of ART and controlled HIV-replication (HIV-viral load, VL <20 copies/mL for ≥1 year). Residual HIV-VL was measured using an ultrasensitive assay (quantification limit: 1 copy/ml). Patients were categorized as having detectable (D; 1-20 copies/mL, n = 14) or undetectable (UD; <1 copies/mL, n = 33) HIV-VL. Linear regression was used to model the difference in total carotid intima-media thickness [c-IMT, measures averaged across common carotid artery (cca), bifurcation, and internal carotid artery] and cca-IMT alone across detection groups. Multivariable models were constructed for each endpoint in a forward-stepwise approach.

Results

No significant differences were observed between viremia groups with respect to median ART-duration (9.6 years, IQR = 6.8–10.9), nadir CD4+T-cell (208/mm³, IQR = 143–378), and CD4+T-cell count (555/mm³, IQR = 458–707). Median adjusted inflammatory markers tended to be higher in patients with D- than UD-viremia, with differences in IL-10 being significant (p = 0.03). After adjustment on age, systolic blood pressure, and insulin resistance, mean cca-IMT was significantly lower in patients with undetectable (0.668 mm±0.010) versus detectable viremia (0.727 mm±0.015, p = 0.002). Cca-IMT was also independently associated with age and insulin resistance. Mean adjusted total c-IMT was no different between viremia groups (p = 0.2), however there was large variability in bifurcation c-IMT measurements.

Conclusions

Higher cca-IMT was observed in patients with detectable, compared to undetectable, HIV-VL in never-smoking ART-controlled patients, suggesting that residual HIV viremia may be linked to atherosclerosis.

Common Carotid Artery Thickness in Chronic Kidney Disease

AIM: Previous studies showed that patients with chronic kidney disease (CKD) > 2 dergee had increased intima-media thickness (IMT).  We evaluate the relationship between IMT and parameters for renal function.METHODS: 130 subjects were examined – 66 with CKD, 44 without CKD, as well as 20 healthy volunteers. The first group- patients with CKD were with creatinine clearance (CrCl) over 20 ml/min and below 90 ml/min. The second group included 44 pts. with normal renal function, CrCl > 90 ml/min. All examined patients with and without CKD had hypertension.   The two groups were streamed into two subgroups: with and without vascular disease. To evaluate the renal function creatinine clearance was calculated in ml/min. IMT was measured in both common carotid artery (CCA) using high resolution sonography in all examined subjects.RESULTS: CCA IMT increased in pts. with CKD and was > 0.75 ( 0.76 ± 0.14 v.s contols 0.59 ± 0.10) Patients with vascular disease (VD) had higher IMT which increased significant when CKD with GFR < 90 ml/min was included (0.77 ± 0.06/0.81 ± 0.10, p < 0.05). Multiple regression analysis proved that renal function deterioration directly affected CCA IMT (R2=0.208, p=0.022).CONCLUSION: Increased IMT is presented in mild renal dysfunction. CKD –GFR< 90 ml/min could be an independent vascular risk factor.

Association between betel quid chewing and carotid intima-media thickness in rural Bangladesh

BACKGROUND

Areca nut, more commonly known as betel nut, is the fourth most commonly used addictive substance in the world. Though recent evidence suggests it may play a role in the development of cardiovascular disease, no studies have investigated whether betel nut use is related to subclinical atherosclerosis.

METHODS

We evaluated the association between betel nut use and subclinical atherosclerosis in 1206 participants randomly sampled from the Health Effects of Arsenic Longitudinal Study (HEALS). Frequency and duration of betel nut use were assessed at baseline, and carotid IMT was measured on average 6.65 years after baseline.

RESULTS

A positive association was observed between duration and cumulative exposure (function of duration and frequency) of betel nut use and IMT, with above-median use for duration (7 or more years) and cumulative exposure (30 or more quid-years) corresponding to a 19.1 μm [95% confidence interval (CI): 5.3-32.8; P ≤ 0.01] and 16.8 μm (95% CI: 2.9-30.8; P < 0.05) higher IMT in an adjusted model, respectively. This association was more pronounced in men [32.8 μm (95% CI: 10.0-55.7) and 30.9 μm (95% CI: 7.4-54.2)]. There was a synergy between cigarette smoking and above-median betel use such that the joint exposure was associated with a 42.4 μm (95% CI: 21.6-63.2; P ≤ 0.01) difference in IMT.

CONCLUSION

Betel nut use at long duration or high cumulative exposure levels is associated with subclinical atherosclerosis as manifested through carotid IMT. This effect is especially pronounced among men and cigarette smokers.

Infection duration and inflammatory imbalance are associated with atherosclerotic risk in HIV-infected never-smokers independent of antiretroviral therapy

OBJECTIVES

To determine whether the reported increased atherosclerotic risk among HIV-infected individuals is related to antiretroviral therapy (ART) or HIV infection, whether this risk persists in never-smokers, and whether inflammatory profiles are associated with higher risk.

DESIGN

Matched cross-sectional study.

METHODS

A total of 100 HIV-infected patients (50 ART-treated >4 years, 50 ART-naive but HIV-infected >2 years) and 50 HIV-negative controls were recruited in age-matched never-smoking male triads (mean age 40.2 years). Carotid intima-media maximal thickness (c-IMT) was measured across 12 sites. Pro-inflammatory [highly sensitive C-reactive protein (hs-CRP), resistin, interleukin-6, interleukin-18, insulin, serum amyloid A, D-dimer) and anti-inflammatory (total and high molecular weight adiponectin, interleukin-27, interleukin-10) markers were dichotomized into high/low scores (based on median values). c-IMT was compared across HIV/treatment groups or inflammatory profiles using linear regression models adjusted for age, diabetes, hypertension, and, for HIV-infected patients, nadir CD4 cell counts.

RESULTS

Although adjusted c-IMT initially tended to be thicker in ART-exposed patients (P=0.2), in post-hoc analyses stratifying by median HIV duration we observed significantly higher adjusted c-IMT in patients with longer (>7.9 years: 0.760±0.008 mm) versus shorter prevalent duration of known HIV infection (<7.9 years: 0.731±0.008 mm, P=0.02), which remained significant after additionally adjusting for ART (P=0.04). Individuals with low anti-inflammatory profile (<median versus >median score) had thicker c-IMT (0.754±0.006mm versus 0.722±0.006 mm, P<0.001), with anti-inflammatory markers declining as prevalent duration of HIV infection increased (P for linear trend <0.001).

CONCLUSION

Known HIV duration is related to thicker c-IMT, irrespective of ART, in these carefully selected age-matched never-smoking HIV-treated and ART-naive male individuals. Higher levels of anti-inflammatory markers appeared protective for atherosclerosis.

Low-grade albuminuria is associated with early but not late carotid atherosclerotic lesions in community-based patients with type 2 diabetes

Background

Low-grade albuminuria is associated with cardiovascular risk factors and mortality. Our aim was to investigate the association between low-grade albuminuria and carotid atherosclerotic lesions in community-based patients with type 2 diabetes.

Methods

A cross-sectional study was performed in 475 community-based patients with type 2 diabetes (190 males and 285 females) with normal urinary albumin-to-creatinine ratios (UACR) (< 3.5 mg/mmol) from Shanghai, China. The subjects were stratified into tertiles based on UACR levels (the lowest tertile was UACR ≤ 1.19 mg/mmol, and the highest tertile was UACR ≥ 2 mg/mmol). Carotid intima-media thickness (CIMT), carotid atherosclerotic plaque formation and stenosis were assessed and compared among the three groups based on ultrasonography. The urinary albumin excretion rate was determined as the mean of the values obtained from three separate early morning urine samples.

Results

Compared with the subjects with UACR in the lowest tertile, the subjects with UACR in the middle and highest tertiles had greater CIMT values (0.88 ± 0.35 mm, 0.99 ± 0.43 mm and 1.04 ± 0.35 mm, respectively; all p < 0.05) and a higher prevalence of carotid atherosclerotic plaques (25.3%, 39.0% and 46.2%, respectively; all p < 0.05) after adjusting for sex and age. Fully adjusted multiple linear regression and logistic regression analyses revealed that UACR tertiles were significantly associated with elevated CIMT (p = 0.007) and that, compared with the subjects in the first tertile of UACR, those in the second and third tertiles had 1.878- and 2.028-fold risk of carotid plaques, respectively. However, there was no statistical association between UACR tertile and the prevalence of carotid stenosis.

Conclusions

Higher UACR within the normal range was independently associated with early but not late carotid atherosclerotic lesions in community-based patients with type 2 diabetes. Low-grade albuminuria contributes to the risk of carotid atherosclerosis and may be used as an early marker for the detection of atherosclerosis in patients with type 2 diabetes.

Intima-media thickness in patients with obstructive sleep apnea without comorbidities

Background

Obstructive sleep apnea (OSA) is associated with elevated risk of cardiovascular events. The early stages of vascular complications can be visualized by means of ultrasound. Intima-media thickness (IMT) correlates with the presence of risk factors of cardiovascular diseases such as hypertension, diabetes, tobacco smoking, or hyperlipidemia. However, little is known whether OSA itself may be the cause of IMT thickening.

Methods

The study group was composed of 28 patients (6 women, 22 men; mean age = 53.8 years, mean BMI = 27.1 kg/m², mean AHI = 22.4/h) with OSA who had no comorbidities. The control group consisted of 28 healthy subjects (6 women, 22 men; mean age = 53.9 years; mean BMI = 27.5 kg/m²). In both groups IMT was assessed in common carotid arteries with the use of ultrasonography. Additionally, in patients with OSA, pulse wave velocity, echocardiography, 24-h automated blood pressure monitoring, clinical signs and symptoms, and blood tests were performed to investigate possible correlations with IMT.

Results

Median IMT was 0.41 mm in OSA patients and 0.46 mm in the control group (p = 0.087). Echocardiography revealed left ventricle hypertrophy in 21 %, systolic disorders in 8 %, and diastolic disorders in 57 % of the patients. In a large majority of patients, pulse wave velocity was found to be normal. IMT correlated with age (r = 0.446, p = 0.017), total cholesterol (r = 0.518, p = 0.005), daytime systolic blood pressure (r = 0.422, p = 0.025), pulse pressure 24 h and daytime (r = 0.424, p = 0.027 and r = 0.449, p = 0.019), early mitral flow/atrial mitral flow (E/A) (r = −0.429, p = 0.023), and posterior wall diameter (PWD) (r = 0.417, p = 0.270).

Conclusion

In a relatively nonobese group of patients, no significant differences were found in the intima-media thickness between OSA patients without concomitant cardiovascular diseases and healthy controls. This may lead to the conclusion that IMT does not reflect increased risk of cardiovascular events in patients with isolated OSA.

Sonography of common carotid arteries' intima: media thickness in the normal adult population in Sudan

Background:

Carotid ultrasonography is a useful diagnostic tool for assessing carotid disease. It is highly reliable, has no radiation risk, and has no risks when compared to conventional angiography.

Aim:

The study was to determine the common carotid artery (CCA) intima–media thickness (IMT) in the normal adult Sudanese so as to create standards for defining abnormalities.

Materials and Methods:

In 440 participants, the intima–media thickness was obtained sonographically in the supine position at the point of 1 cm section distal to the carotid bulb. Due to ethnic variations, participants were divided into a five ethnic groups according to their geographic distribution in Sudan.

Results:

The ranges of IMT found in the study were from 0.04 cm to 0.07 cm in carotids. Ethnically, males and females from West and East of Sudan show the highest IMT (0.070 ± 0.00 cm and 0.065 ± 0.01 cm) for CCA while males and females from the South of Sudan show the lowest IMT (0.055 ± 0.01 cm and 0.058 ± 0.004 cm).

Conclusion:

Mean carotids’ IMT was slightly higher in females compared to males. No significant differences were found between IMT and different ethnics but significance was noted among participants’ age and IMT of both sexes.

Prevalence and severity of atherosclerosis in extra cranial carotid arteries in Nigeria: an autopsy study

Background

There has been a paucity of autopsy studies on atherosclerotic lesions in Nigerians, the last one conducted at our centre being more than four decades ago. There has also been considerable epidemiological transition. The objective of the study was to determine the frequency, severity, pattern and distribution of atherosclerotic lesions in extra cranial carotid arteries (ECCA) in Nigerians at autopsy.

Methods

ECCA of 30 consecutive Nigerian patients undergoing autopsy at a University teaching hospital were examined using the American Heart Association (AHA) histological grading and classification of atherosclerosis.

Results

Atherosclerotic lesions of ECCA were present in 73.3% of the subjects with the right and the left carotid bifurcations (28.3%) being the most frequently affected sites. Using the AHA classification of atherosclerosis, a total of 176(73.3%) lesions were found in the 240 histological sections of blood vessels examined. Of these, 22.5% were types I, 22.5% were types II, 15.4% were type V, and 7.5% were type III. The VII to type IX lesions were rare. When these atherosclerotic lesions were grouped into mild, moderate and severe, 52.5% were mild lesions (types I-III); 18.3% were moderate lesions (types IV and V); and 2.5% were severe lesions (types VI to IX). The severe lesions were most frequently observed in the left carotid bifurcation (50%) and they first appeared in the age group 45–49 years. Age, hypertension and diabetes mellitus were strong risk factors for atherosclerosis.

Conclusions

Compared with four decades ago there has been an apparent increase in severity and extent of ECCA atherosclerosis especially after the age of 45 years in autopsies from our centre. This change in the amount of atherosclerosis over time is possibly due to the epidemiologic transition. This may worsen the rise in stoke incidence within this community and as such, great effort should be made to follow-up and manage CVD risk factors within the community.

Relationship between chronic stress and carotid intima-media thickness (IMT) in elderly Alzheimer's disease caregivers

The stress associated with providing care for a spouse diagnosed with Alzheimer's disease can have adverse effects on cardiovascular health. One potential explanation is that chronic caregiving stress may contribute to the development of atherosclerosis. The purpose of this study was to determine whether the duration that one has provided care is associated with the degree of atherosclerotic burden, as measured by carotid artery intima-media thickness (IMT). One hundred and ten Alzheimer caregivers [mean age 74 ± 8 (SD) years, 69% female] underwent in-home assessment of carotid artery IMT via B-mode ultrasonography. Data regarding medical history, blood pressure, and multiple indicators of caregiving stress were also collected. Multiple regression indicated that duration of care was positively associated with IMT measured in the internal/bifurcation segments of the carotid artery (β = 0.202, p = 0.044) independent of risk factors such as age, gender, body mass index, smoking history, sleep quality, hypertension status, and caregiving stressors. Duration of care was positively associated with IMT in the common carotid artery, but the relationship was not significant. These findings provide more evidence of the link between chronic caregiving stress and cardiovascular disease and indicate that enduring the experience of caregiving over a period of years might be associated with atherosclerotic burden.

Integrated Evaluation of Age-Related Changes in Structural and Functional Vascular Parameters Used to Assess Arterial Aging, Subclinical Atherosclerosis, and Cardiovascular Risk in Uruguayan Adults: CUiiDARTE Project

This work was carried out in a Uruguayan (South American) population to characterize aging-associated physiological arterial changes. Parameters markers of subclinical atherosclerosis and that associate age-related changes were evaluated in healthy people. A conservative approach was used and people with nonphysiological and pathological conditions were excluded. Then, we excluded subjects with (a) cardiovascular (CV) symptoms, (b) CV disease, (c) diabetes mellitus or renal failure, and (d) traditional CV risk factors (other than age and gender). Subjects (n = 388) were submitted to non-invasive vascular studies (gold-standard techniques), to evaluate (1) common (CCA), internal, and external carotid plaque prevalence, (2) CCA intima-media thickness and diameter, (3) CCA stiffness (percentual pulsatility, compliance, distensibility, and stiffness index), (4) aortic stiffness (carotid-femoral pulse wave velocity), and (5) peripheral and central pressure wave-derived parameters. Age groups: ≤20, 21-30, 31-40, 41-50, 51-60, 61-70, and 71-80 years old. Age-related structural and functional vascular parameters profiles were obtained and analyzed considering data from other populations. The work has the strength of being the first, in Latin America, that uses an integrative approach to characterize vascular aging-related changes. Data could be used to define vascular aging and abnormal or disease-related changes.

[Carotid intima-media thickness in diabetics and hypertensive patients]

The aims of this study are to describe the mean values of carotid intima-media thickness and how it increases with age, and to compare carotid injury in diabetics and hypertensive patients with that of controls. We included 562 subjects (121 diabetics, 352 hypertensive patients, 89 controls). The mean intima-media thickness was 0.781 mm in diabetics, 0.738 mm in hypertensive patients and 0.686 mm in controls. The difference in intima-media thickness between diabetics and controls and between hypertensive patients and controls, adjusted for age, was 0.040 and 0.026 mm, respectively. We observed an increase in intima-media thickness of 0.005 mm in diabetics and of 0.005 mm in controls with every additional year of age. We found carotid damage in 23% of the diabetics, 12% of the hypertensive patients and 3.4% of the controls. In conclusion, the intima-media thickness is greater in diabetics, but the annual increase in the thickness is greater in hypertensive patients. Full English text available from:www.revespcardiol.org.

Effect of vascular risk factors on increase in carotid and femoral intima-media thickness. Identification of a risk scale

BACKGROUND

The well established correlation between intima-media thickness (IMT) and the risk of cardiovascular and cerebrovascular events and death is usually measured in subjects with multiple vascular risk factors, which makes it difficult, after application of the usual analysis-of-variance linear combination of effects model, to establish whether each cardiovascular risk factor has, per se, an effect on IMT.

METHOD AND RESULTS

In this study we investigated five "pure" groups of patients (865), i.e. each presenting only one of the following risk factors: hypertension, obesity, overweight, smoking, hypercholesterolaemia and a control group of 37 healthy subjects. We measured, both as discrete and as continuous variables, the following indices: intima-media thickening of the common carotid artery (IMT(C)) and of the common femoral artery (IMT(F)) and the ankle-brachial index (ABI). Descriptive statistics were used to analyse the prevalence of pathological values for the three indices in the different groups. Subsequently the entire group of 902 subjects was included in a correlation analysis in which the Pearson correlation coefficient for each pair of variables was computed. In order to assign the risk factors a continuous ranking, and obtain a more general idea of the correlation structure, principal component analysis (PCA) was used. The scores obtained from PCA made it possible to build a scale of severity of the vascular risk factors considered. All the risk factors considered were demonstrated to strongly affect the studied indices. Overweight was shown to be the least important risk factor with regard to intima-media thickening, followed by smoking, hypercholesterolaemia, hypertension and finally obesity, which emerged as the greatest risk factor.

CONCLUSIONS

The strong correlation between the indices made it possible to compute a composite general score, which provides an univocal risk estimation at single-patient level. IMT(F) was demonstrated to be the most sensitive descriptor. The construction of this risk scale has implications for preventive treatment and the frequency of instrumental examinations, allowing clear quantitative definition of the extent of the damage.

Postprandial glucose and not triglyceride concentrations are associated with carotid intima media thickness in women with normal glucose metabolism: the Hoorn prandial study

The present study aimed to compare the associations of postprandial glucose (ppGL) and postprandial triglycerides (ppTG) with carotid intima media thickness (cIMT) in women with normal glucose metabolism (NGM) and type 2 diabetes (DM2). Post-menopausal women (76 with NGM, 78 with DM2), received two consecutive fat-rich and two consecutive carbohydrate-rich meals on separate occasions. Blood samples were taken before and 1, 2, 4, 6 and 8h following breakfast; lunch was given at t=4. Ultrasound imaging of the carotid artery was performed to measure cIMT. In women with NGM, an increase of 1.0 mmol/l glucose following the fat-rich meals was associated with a 50 microm cIMT increase (p=0.04), and following the carbohydrate meals, an increase of 1.8 mmol/l glucose was associated with a 50 microm larger cIMT (p=0.08). These associations were not explained by classical cardiovascular risk factors. However, no association between ppGL and cIMT was found in women with DM2 and ppTG were not associated with cIMT. The association between ppGL and cIMT in normoglycaemic women suggests that ppGL in the normal range is a marker or a risk factor for atherosclerosis. Postprandial glucose levels might be a better indicator of risk than post-OGTT glucose levels or triglyceride levels.

[Carotid ultrasound in the assessment of preclinical atherosclerosis. Distribution of intima-media thickness values and plaque frequency in a Spanish community cohort]

BACKGROUND AND OBJECTIVE

High-resolution B-mode ultrasound measurements of carotid intima-media thickness (IMT) and determination of plaque presence are useful to assess preclinical atherosclerosis. Normal IMT values have not been reported in Spanish subjects. Our aim was to define normality data of carotid ultrasound by sex and age.

SUBJECTS AND METHODS

We studied 250 healthy, normolipidemic subjects, 125 men and 125 women, with mean age 49 years (range, 20-81). We assessed cardiovascular risk factors and performed ultrasound determination of mean and maximum IMT in the far wall of the common carotid artery, plaque occurrence, and maximum plaque height.

RESULTS

Reference values for carotid IMT, expressed as 25th, 50th, and 75th percentiles by sex and 5 age groups, have been obtained. The 50th percentiles of mean IMT ranged from 0.50 to 0.74 mm in men in the age groups 35 years or younger and 65 years or older, respectively. For women, corresponding IMT values ranged from 0.40 to 0.65 mm. IMT was strongly related (p < 0.001) to age, both in men (r = 0.57) and women (r = 0.61). From the regression equations, the estimated yearly increase in IMT was 0.005 mm in men and 0.007 mm in women. More than 50% of men aged 55 years and older, and of women aged 65 years and older, had carotid plaques.

CONCLUSIONS

Both IMT and plaque frequency were associated with age in men and women. Carotid IMT values in a Spanish community cohort were lower than those reported for countries with higher cardiovascular risk, such as Northern European countries and the US.

Lack of association between carotid intima-media thickness and PAF-acetylhydrolase mass and activity in patients with primary hyperlipidemia

Carotid intima media thickness (IMT), represents an important clinical indicator of early atherosclerosis. Human plasma platelet-activating factor acetylhydrolase (PAF-AH) is an enzyme primarily associated with low-density lipoprotein (LDL) while a small proportion of enzymatic activity is also associated with high-density lipoprotein (HDL). Plasma paraoxonase 1 (PON1) is an esterase exclusively associated with HDL. The authors investigated the possible relationship between carotid IMT and the plasma levels of PAF-AH mass and activity as well as the PON1 activity in hyperlipidemic patients. One hundred unrelated patients with primary hyperlipidemia and 67 age-and sex-matched normolipidemic apparently healthy volunteers participated in the study. The PAF-AH activity in total plasma and in HDL-rich plasma (HDL-PAF-AH activity), the plasma PAF-AH mass, and the serum PON1 activities toward paraoxon and phenyl acetate were determined. The plasma PAF-AH mass and activity were higher in hyperlipidemic patients compared to controls, whereas the HDL-PAF-AH activity, as well as the serum PON1 activities were not significantly different between the studied groups. When hyperlipidemic patients were divided into 2 subgroups according to their IMT values (IMT <0.7 mm and IMT > or =0.7 mm) patients with IMT > or =0.7 mm had significantly higher age, and serum triglyceride concentrations, whereas no difference was found in the plasma PAF-AH mass and activity as well as in the HDL-PAF-AH activity between the 2 studied subgroups. The same phenomenon was observed for serum PON1 activities. In a multivariate analysis, only the age was significantly correlated with IMT values (p<0.05). Neither the total plasma PAF-AH mass and activity nor the HDL-PAF-AH activity are associated with early carotid atherosclerosis.

Periodontal microbiota and carotid intima-media thickness: the Oral Infections and Vascular Disease Epidemiology Study (INVEST)

BACKGROUND

Chronic infections, including periodontal infections, may predispose to cardiovascular disease. We investigated the relationship between periodontal microbiota and subclinical atherosclerosis.

METHODS AND RESULTS

Of 1056 persons (age 69+/-9 years) with no history of stroke or myocardial infarction enrolled in the Oral Infections and Vascular Disease Epidemiology Study (INVEST), we analyzed 657 dentate subjects. Among these subjects, 4561 subgingival plaque samples were collected (average of 7 samples/subject) and quantitatively assessed for 11 known periodontal bacteria by DNA-DNA checkerboard hybridization. Extensive in-person cardiovascular risk factor measurements, a carotid scan with high-resolution B-mode ultrasound, white blood cell count, and C-reactive protein values were obtained. In 3 separate analyses, mean carotid artery intima-media thickness (IMT) was regressed on tertiles of (1) burden of all bacteria assessed, (2) burden of bacteria causative of periodontal disease (etiologic bacterial burden), and (3) the relative predominance of causative/over other bacteria in the subgingival plaque. All analyses were adjusted for age, race/ethnicity, gender, education, body mass index, smoking, diabetes, systolic blood pressure, and LDL and HDL cholesterol. Overall periodontal bacterial burden was related to carotid IMT. This relationship was specific to causative bacterial burden and the dominance of etiologic bacteria in the observed microbiological niche. Adjusted mean IMT values across tertiles of etiologic bacterial dominance were 0.84, 0.85, and 0.88 (P=0.002). Similarly, white blood cell values increased across tertiles of etiologic bacterial burden from 5.57 to 6.09 and 6.03 cells x10(9)/L (P=0.01). C-reactive protein values were unrelated to periodontal microbial status (P=0.82).

CONCLUSIONS

Our data provide evidence of a direct relationship between periodontal microbiology and subclinical atherosclerosis. This relationship exists independent of C-reactive protein.

[A new strategy of aging and geriatric epidemiology in Japan]

Global trends of increases in the aging population will continue in the 21st century, and geriatric medicine will be a most important field of medicine. Increase in the aging population naturally causes increases in numbers of patients with geriatric disease. Geriatric diseases are often chronic, slowly progressive, and hard to cure. Medical care expenses for the patients will expand dramatically. Therefore, the most important key for future geriatric medicine is prevention. For prevention, detailed data on normal aging process are required. At the National Institute for Longevity Sciences (NILS), a comprehensive longitudinal study of aging, the NILS-Longitudinal Study of Aging (NILS-LSA) started in November 1997. The subjects of this study were about 2,300 residents aged 40 to 79 years who were stratified random samples selected from the neighborhood area of the NILS. They are examined every two years at the NILS-LSA Examination Center. The third wave of examinations started in 2002. Examined variables were over 1,000, including clinical evaluations, medical examinations, anthropometry, body composition, physical functions, physical activities, psychological assessments, nutritional analysis and molecular epidemiology.

Impaired carotid and femoral viscoelastic properties and elevated intima-media thickness in peripheral vascular disease

BACKGROUND

We undertook a study to determine whether peripheral vascular disease of the lower extremity (PVD) per se affects the arterial viscoelastic properties and intima-media thickness (IMT) of the carotid and femoral arteries.

METHODS

Thirty-five patients with PVD, 35 age- and gender-matched control subjects were examined with ultrasound scan wall tracking system, with the simultaneous measurement of blood pressure for carotid and femoral IMT and viscoelastic properties.

RESULTS

Subjects with PVD have significantly impaired carotid elastic properties including compliance (mean (SD): 6.50 (2.39) vs 9.93 (4.07) %mmHg(-1)x10(-2), P<0.001), Petersen's elastic modulus (1.77 (0.69) vs 1.19 (0.63) mmHg x 10(3), P=0.001) and stiffness index (17.92 (7.21) vs 12.10 (6.17), P=0.001) when compared to non-PVD controls. They also have significantly altered femoral elastic properties including Petersen's elastic modulus (5.94 (4.98) vs 3.64 (3.27) mmHg x 10(3), P=0.025) and stiffness index (58.42 (47.76) vs 36.96 (33.43), P=0.033). The carotid (0.85 (0.35) vs 0.59 (0.23) mm, P<0.001) and femoral (1.05 (0.39) vs 0.69 (0.31) mm, P<0.001) IMTs are also significantly elevated in PVD patients. After adjustment for the presumed cardiovascular load assessed on the basis of a cumulative total vascular risk score, as well as age, systolic and diastolic pressure, the carotid viscoelastic indices and the carotid and femoral IMTs remained highly significant. However, the difference in femoral elastic variables was no longer evident.

CONCLUSION

PVD per se affects the femoral and carotid wall mechanics and morphology similarly to other cardiovascular risk factors and events. These parameters may provide further information for cardiovascular risk assessment in addition to the classical risk factors and the Framingham equation. Indeed, some guidelines have suggested that additional factors such as the carotid scan may influence the clinician's decision to intervene with therapy.