Carotid artery diameter correlates with risk factors for cardiovascular disease in a population of 55-year-old subjects

Carotid artery wall hypertrophy in children with metabolic syndrome

Preclinical vascular changes (increased stiffness and/or wall thickness) have been observed in children with known metabolic risk factors. Aim of the present study was to evaluate different carotid parameters, representative of vascular health, in children with and without metabolic syndrome (MS). We studied 38 children with MS (mean age 9.6+/-2.6 years; range 6-14 years) and 45 healthy age-matched subjects. Children who met three or more of the following criteria qualified as having the MS: fasting glucose >110 mg dl(-1), fasting triglyceride concentration >100 mg dl(-1), fasting high-density lipoprotein cholesterol concentration <50 mg dl(-1) for females or <45 mg dl(-1) for the males, waist circumference >75th percentile for age and gender and systolic or diastolic blood pressure >90th percentile for age, gender and height. Carotid B-mode ultrasound examinations were performed and intima-media thickness and diameters were measured in all subjects. Arterial geometry was further characterized by calculation of carotid cross-sectional area. Carotid intima-media thickness and lumen diameters were increased in children with MS as compared to children without MS. Moreover, carotid cross-sectional area was significantly higher in the group of children with MS 9.83+/-1.86 mm(2) [mean+/-s.d.] compared with the control group: 7.77+/-1.72 mm(2), P<0.001, even after adjustment for age, gender and height. Carotid hypertrophy is already detectable in children with MS. High-resolution B-mode ultrasound could provide a valuable tool for the cardiovascular risk stratification of children.

Noninvasive Young's modulus evaluation of tissues surrounding pulsatile vessels using ultrasound Doppler measurement

This paper presents an indirect approach to estimating the mechanical properties of tissues surrounding the arterial vessels using ultrasound (US) Doppler measurements combined with an inverse problem-solving method. The geometry of the structure and the dynamic behavior of the inner fluid are first evaluated using a novel dual-beam US system. A numerical phantom associated with a parametric finite element simulator that calculates the hydrodynamic pressure and the displacement on the walls' boundaries is then built. The simulation results are iteratively compared to the US measurement results to deduce the value of the unknown parameters, i.e., the Young's modulus and the pressure resulting from the downstream load. The feasibility of the proposed approach was experimentally tested in vitro using a phantom composed of a latex tube surrounded by a cryogel tissue-mimicking material.

Association of endothelial function and vascular data with LDL-c and HDL-c in a homogeneous population of middle-aged, healthy military men: Evidence for a critical role of optimal lipid levels

BACKGROUND

Modifying lipids levels underpins atherosclerosis prevention. Flow-mediated dilation (FMD) could advise which patients to treat and to what extent. Little is known about the influence of near-normal lipid levels on the endothelium and the mechanisms related to different lipid fractions. We studied associations between FMD and lipids, focusing on normal lipid levels.

METHODS

An age-homogeneous sample of 171 healthy, untreated military men (mean age 35.5+/-1.1 years) was studied: serum lipid determination and brachial artery ultrasound with a forearm ischemia cuff and automated measurement were performed. NCEP-ATP III groups were used.

RESULTS

Significantly smaller vessel diameters were found among individuals with high HDL-c (4.10 mm vs. 4.24 mm), optimal LDL-c (4.00 mm vs. 4.22 mm), and normal triglycerides (<150 mg/dl) (4.15 mm vs. 4.31 mm). Basal diameter correlated significantly with HDL-c and triglycerides. There were significant differences in FMD between low HDL-c compared to the rest (4.13% vs. 5.07%) and between optimal and near-optimal LDL-c compared to the rest (5.28% vs. 4.56%). HDL-c and LDL-c correlated with FMD. The inverse relation of high LDL-c and FMD is partially due to a decreased stimulus. Besides, stimulus heterogeneity may mask HDL-c link with FMD.

CONCLUSION

Those subjects naturally (not pharmacologically) in the healthy tail-end of the lipid distributions have the best endothelial function and smaller vessels. Functional vascular remodeling might precede anatomical remodeling and, in early stages, vessel size should be considered a risk indicator rather than an atherosclerotic sign. Furthermore, controlling the stimulus seems necessary for detecting the relationship between HDL-c and FMD, and should be performed regularly.

Common carotid artery wall thickness and external diameter as predictors of prevalent and incident cardiac events in a large population study

Background

Arterial diameters enlarge in response to wall thickening, plaques, and many atherosclerotic risk factors. We hypothesized that right common carotid artery (RCCA) diameter would be independently associated with cardiac disease and improve risk discrimination.

Methods

In a middle-aged, biracial population (baseline n = 11225), we examined associations between 1 standard deviation increments of baseline RCCA diameter with prevalent myocardial infarction (MI) and incident cardiac events (MI or cardiac death) using logistic regression and Cox proportional hazards models, respectively. Areas under the receiver operator characteristic curve (AUC) were used to estimate model discrimination.

Results

MI was present in 451 (4%) participants at baseline (1987–89), and incident cardiac events occurred among 646 (6%) others through 1999. Adjusting for IMT, RCCA diameter was associated with prevalent MI (female OR = 2.0, 95%CI = 1.61–2.49; male OR = 1.16, 95% CI = 1.04–1.30) and incident cardiac events (female HR = 1.75, 95% CI = 1.51–2.02; male HR = 1.27, 95% CI = 1.15–1.40). Associations were attenuated but persisted after adjustment for risk factors (not including IMT) (prevalent MI: female OR = 1.73, 95% CI = 1.40–2.14; male OR = 1.14, 95% CI = 1.02–1.28, and incident cardiac events: female HR = 1.26, 95% CI = 1.08–1.48; male HR = 1.19, 95% CI = 1.08–1.32). After additional adjustment for IMT, diameter was associated with incident cardiac events in women (HR = 1.18, 95% CI = 1.00–1.40) and men (HR = 1.17, 95% CI = 1.06–1.29), and with prevalent MI only in women (OR = 1.73; 95% CI = 1.37–2.17). In women, when adjustment was limited, diameter models had larger AUC than other models.

Conclusion

RCCA diameter is an important correlate of cardiac events, independent of IMT, but adds little to overall risk discrimination after risk factor adjustment.

Detailed exploration of the endothelium: parameterization of flow-mediated dilation through principal component analysis

Endothelial dysfunction is associated with cardiovascular diseases and their risk factors (CVRF), and flow-mediated dilation (FMD) is increasingly used to explore it. In this test, artery diameter changes after post-ischaemic hyperaemia are classically quantified using maximum peak vasodilation (FMDc). To obtain more detailed descriptors of FMD we applied principal component analysis (PCA) to diameter-time curves (absolute), vasodilation-time curves (relative) and blood-velocity-time curves. Furthermore, combined PCA of vessel size and blood-velocity curves allowed exploring links between flow and dilation. Vessel diameter data for PCA (post-ischaemic: 140 s) were acquired from brachial ultrasound image sequences of 173 healthy male subjects using a computerized technique previously reported by our team based on image registration (Frangi et al 2003 IEEE Trans. Med. Imaging 22 1458). PCA provides a set of axes (called eigenmodes) that captures the underlying variation present in a database of waveforms so that the first few eigenmodes retain most of the variation. These eigenmodes can be used to synthesize each waveform analysed by means of only a few parameters, as well as potentially any signal of the same type derived from tests of new patients. The eigenmodes obtained seemed related to visual features of the waveform of the FMD process. Subsequently, we used eigenmodes to parameterize our data. Most of the main parameters (13 out of 15) correlated with FMDc. Furthermore, not all parameters correlated with the same CVRF tested, that is, serum lipids (i.e., high LDL-c associated with slow vessel return to a baseline, while low HDL-c associated with a lower vasodilation in response to similar velocity stimulus), thus suggesting that this parameterization allows a more detailed and factored description of the process than FMDc.

Monitoring Carotid Blood Flow and ECG for Cardiovascular Disease in Elder Subjects

This report is to investigate the correlation between common carotid blood flow (CCBF) properties and the risk factors for cardiovascular disease. The measurement system was designed for simultaneously monitoring of CCBF and electrocardiogram (ECG) in order to get more valid information for detection and diagnosis of cardiovascular disease. In our study, blood flow velocimeter was developed to measure blood flow in carotid by using ultrasound Doppler technique. This measurement system is based on a continuous-wave (CW) Doppler ultrasound method with two semicircular piezoelectric (PZT) transducers, one continuously transmitting ultrasound, and the other continuously receiving the echoes. Eleven patients with cardiovascular disease underwent in the experiment. In the report, blood flow was compared with data from 25 healthy subjects which asymptomatic subjects putatively free of cardiovascular disease as controls. The maximum of CCBF velocity was 102.8 (SD 18.3) cm/s in the 25 healthy subjects. While, the maximum of CCBF velocities were 53.9 (SD 16.6) cm/s in the eleven cardiac patients. The data suggest that CCBF velocity decreased significantly in the cardiac patients and by simultaneously monitoring of CCBF and ECG were probably obtained more valid information to detect and diagnose cardiovascular disease at the early stage.

Large brachial and common carotid artery diameter in postmenopausal women with carotid atherosclerosis

BACKGROUND AND PURPOSE

It is recognized that arteries can enlarge to compensate atherosclerosis. The role of diameter enlargement of unaffected arteries is not well known. We hypothesized that brachial and common carotid arteries diameters were larger in subjects with carotid atherosclerosis compared to subjects without these lesions.

METHODS

We measured diameters in the common carotid and brachial arteries. Intimal medial thickness (IMT) of carotid arteries and carotid atherosclerosis were also evaluated using ultrasound in 83 cases and 83 disease-free control subjects.

RESULTS

Common carotid and brachial diameter was greater in cases (subjects with carotid atherosclerosis) than controls (subjects without carotid atherosclerosis) after adjustment for confounding variables (P<0.02). Common carotid diameter was also larger in individuals with greater IMT (P<0.0001), whereas brachial artery diameter was not. Subjects with more than one carotid plaque had larger arterial diameters than those with one or without plaques.

CONCLUSIONS

Common carotid and brachial artery diameters are both larger in cases than controls. This result suggests that vascular remodeling is a systemic process and not only a local response to atherosclerosis. The relationship between diameters and burden of disease could also suggest a link between vascular remodeling and severity of disease. Finally, if confirmed in prospective studies, brachial artery diameter could help to identify subjects at high cardiovascular risk, at least in postmenopausal women.

Association between risk factors and carotid enlargement

OBJECTIVE

The aim of this study was to evaluate the influence of conventional cardiovascular risk factors on the degree of adaptive response of the carotid arterial wall to atherosclerotic disease.

PATIENTS AND METHODS

We evaluated the diameter and intima-media thickness (IMT) of common carotid artery (CCA) by ultrasonography in 351 men aged 70.3 (range, 14-97) years and 474 women aged 75.6 (range, 19-103) years in the medical department of Seiyo Municipal Nomura Hospital. We assessed cross-sectionally the relationships between CCA diameter and IMT and cardiovascular risk factors by gender.

RESULTS

In multiple linear regression analyses, after controlling for traditional cardiovascular risk factors, a significant correlation was found between CCA diameters and age (p=0.034), body mass index (BMI) (p<0.001), smoking status (p=0.039), alcohol consumption (<0.001) and uric acid (UA) (p=0.021) in men, and between CCA diameters and age (<0.001), BMI (p<0.001), systolic blood pressure (SBP) (p=0.013) and antihypertensive drug use (p=0.005) in women. Analysis of covariance showed that the two regression lines between carotid IMT and diameter in those with or without plaque were significantly different in both men (F=16.4; p<0.001) and women (F=15.0; p<0.001). After adjustment for carotid IMT and plaque, associations with carotid diameters still persisted for age (p<0.001), BMI (p<0.001), smoking status (p=0.006), alcohol consumption (p<0.001) and SBP (p=0.001) in men, and age (p=0.005), BMI (p<0.001), SBP (p=0.047) and UA (p=0.001) in women.

CONCLUSION

This study shows that the CCA diameters correlated with conventional cardiovascular risk factors including alcohol consumption. These findings suggest that the CCA diameters may reflect the ability of adaptive remodeling to the atherosclerosis before plaque formation and can be an important factor during the development of atherosclerosis.

Changing associations between progressive cardiovascular autonomic neuropathy and carotid atherosclerosis with increasing duration of type 2 diabetes mellitus

To clarify associations between cardiovascular autonomic neuropathy (CAN) and the progression of carotid artery atherosclerosis in Type 2 diabetic patients, cardiovascular autonomic nerve function was related to carotid artery ultrasound in 61 Type 2 diabetic patients, 5 and 8 years after the diagnosis of diabetes. Between 5 and 8 years after diagnosis, age-adjusted acceleration index (AI) decreased (from -0.306+/-1.034 to -0.702+/-1.072; P=.0139), whereas age-adjusted expiration/inspiration (E/I) ratio was unchanged (-0.583+/-1.038 and -0.828+/-1.028; P=.1164). Intima-media thickness (IMT) increased in both the common carotid artery (CCA; from 0.854+/-0.219 to 0.913+/-0.241 mm; P<.0001) and the carotid bulb (from 1.789+/-0.714 to 2.128+/-0.881 mm; P<.0001), corresponding to a yearly IMT increase of 0.032+/-0.039 mm in the CCA and 0.146+/-0.204 mm in the carotid bulb. This value did not correlate with the AI or E/I ratios. In age-controlled partial correlation in the first examination, AI correlated inversely with mean (r=-.33, P=.018) IMT in the CCA, but not with IMT in the carotid bulb (r=-.14, P=.303). However, in contrast to the first examination, at follow-up, AI correlated inversely with the mean IMT of the carotid bulb (r=-.40, P=.007), lumen diameter of the CCA (r=-.31, P=.034), and plaque score (r=-.29, P=.041), but not with IMT of the CCA (r=-.04, P=.861). There were no correlations between the E/I ratio and carotid variables. In conclusion, CAN was associated with features of carotid atherosclerosis, which, in the carotid bulb, might affect baroreceptor function with the progression of Type 2 diabetes.

Implications of carotid arteriomegaly in patients with aortic aneurysm

The pathophysiology of aortic aneurysm is complex and it has remained unclear how frequently arteriomegaly, a diffuse dilatation of the artery, is associated with aneurysm. Therefore, ultrasonic study of the carotid artery was conducted to clarify this issue in a large number of subjects. Carotid ultrasonography was performed in 1,108 Japanese men aged 50 or older, and the results of 379 patients with arteriosclerotic aortic aneurysm (AA) were compared with those of 211 patients with peripheral arterial disease, 65 patients with aortic dissection, 232 hypertensive subjects, and 221 normotensive subjects. The carotid diameter was measured bilaterally at two points on the common carotid artery, and we defined carotid arteriomegaly as an arterial diameter in the 95th percentile or above that in the normotensive control group according to the relevant age subgroups. The incidence of carotid arteriomegaly in the AA group (25.9%) was significantly higher than in the other groups (p < 0.01) even when adjusted for body height and blood pressure. In the arteriomegaly subgroup, hypertension and cigarette smoking was significantly more frequent than in the non-dilated artery subgroup. This study demonstrates that one fourth of patients with aortic aneurysm have arteriomegaly as a generalized systemic abnormality in the arterial wall.

Carotid artery flow volume and velocity by duplex sonography in men with chronic low thoracic and lumbar spinal cord injury

OBJECTIVE

To investigate the common carotid blood flow volume and velocity in men with chronic low thoracic and lumbar spinal cord injury (SCI), using duplex sonography.

DESIGN

Experimental control study.

SETTING

University laboratory in a department of rehabilitation medicine.

PARTICIPANTS

Twenty men with SCI between the T7 and L1 segments and 15 age- and sex-matched control subjects.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Common carotid artery flow volume and velocity.

RESULTS

The mean carotid artery time-averaged flow velocity of subjects with SCI was significantly lower than that of control subjects. Moreover, the mean carotid flow volume of subjects with SCI was significantly lower than that of control subjects (right side: SCI, .52+/-.14 L/min; controls, .67+/-.10 L/min; P <.05; left side: SCI, .54+/-.15 L/min; controls, .72+/-.14 L/min; P <.05).

CONCLUSIONS

There are reduced common carotid artery flow volumes and flow velocities in men with chronic SCI. The reduction may result from disturbances of blood distribution induced by reduced vasoconstriction tone below the level of SCI lesion.

Cardiovascular risk factors associated with enlarged diameter of the abdominal aortic and iliac arteries in healthy women

The abdominal aorta is known to be more susceptible to arterial dilation than to occlusion primarily due to the effects of vascular aging. Few studies have considered the effects of cardiovascular risk factors on arterial diameter, particularly within a population of healthy women at mid-life. This study seeks to examine associations between cardiovascular risk factors and abdominal aortic and iliac adventitial diameter. Abdominal aortic ultrasound was performed in 260 post-menopausal women aged 53.9+/-2.5 years at time of scan as a component of the Healthy Women Study. Risk factors were evaluated at premenopause and post-menopausal clinic visits closest in date to the abdominal ultrasound scan. Post-menopausal weight and change of weight from pre- to post-menopause were among the strongest correlates of larger adventitial diameter after controlling for age, systolic blood pressure, and body size using height. Other post-menopausal risk factors significantly correlated with both abdominal aortic and iliac diameter were BMI, waist circumference, HDL, and insulin (p<0.05). These data suggest that weight is a key risk factor in the promotion of vascular aging as indexed by enlarged arterial diameter. Women at mid-life should continue to be targeted for weight interventions to reduce their risk for more serious cardiovascular complications.

Cardiovascular autonomic neuropathy associated with carotid atherosclerosis in Type 2 diabetic patients

AIMS

To clarify if cardiovascular autonomic neuropathy is associated with carotid artery atherosclerotic plaques in Type 2 diabetic patients.

METHODS

Cardiovascular autonomic nerve function was related to carotid artery ultrasound in 61 Type 2 diabetic patients 5-6 years after diagnosis of diabetes.

RESULTS

Cardiovascular autonomic neuropathy [abnormal age corrected expiration/inspiration (E/I) ratio or acceleration index (AI)] was found in 13/61 (21%) patients. Patients with cardiovascular autonomic neuropathy showed increased degree of stenosis in the common carotid artery (24.6 +/- 13.2% vs. 14.7 +/- 9.2%; P = 0.014) and a tendency towards a higher plaque score (4.0 +/- 1.7 vs. 3.2 +/- 1.6; P = 0.064). Controlled for age, AI correlated inversely with degree of stenosis (r = -0.39; P = 0.005), plaque score (r = -0.39; P = 0.005), and mean (r = -0.33; P = 0.018) and maximum (r = -0.39; P = 0.004) intima-media thickness in the common carotid artery. In contrast, E/I ratio correlated only slightly with mean intima-media thickness in the common carotid artery (r = -0.28; P = 0.049).

CONCLUSIONS

Cardiovascular autonomic neuropathy was associated with carotid atherosclerosis in Type 2 diabetic patients. Abnormal E/I ratios reflect efferent structural damage to parasympathetic nerves whereas abnormal AI reflects afferent autonomic dysfunction possibly due to impaired baroreceptor sensitivity secondary to carotid atherosclerosis.

Influence of glucose control, lipoproteins, and haemostasis function on brachial endothelial reactivity and carotid intima-media area, stiffness and diameter in Type 1 diabetes mellitus patients

BACKGROUND

The objectives of this study were to determine the influence of glucose control on lipoprotein and haemostasis variables in Type 1 diabetes mellitus patients and to evaluate the global impact of these metabolic risk factors on brachial artery reactivity and carotid artery atherosclerosis, stiffness and diameter.

DESIGN

Follow up of Type 1 diabetes patients randomized to insulin-intensive conventional treatment (ICT, n = 29) or insulin-standard treatment (ST, n = 25) in the Stockholm Diabetes Intervention Study (SDIS) more than 14 years ago.

RESULTS

The intensive conventional treatment patients had lower glycosylated haemoglobin (HbA1c) compared with the ST patients, i.e. 7.01 (SD 0.51) vs. 8.31 (0.97), while concentrations of the lipoprotein and haemostasis variables analyzed were virtually similar. The carotid artery intima-media area was associated with high HbA1c, high serum (S)-cholesterol levels, and low high-density lipoprotein (HDL)-cholesterol levels. Carotid artery stiffness was associated with high systolic blood pressure, high HbA1c, high fibrinogen, and high HDL-cholesterol. Brachial artery endothelial reactivity was higher for women and those with low S-cholesterol.

CONCLUSION

In patients with Type 1 diabetes, glucose control appeared to have no effect on either lipoproteins or haemostasis variable concentrations. Poor glucose control, and high levels of S-cholesterol, systolic blood pressure and plasma fibrinogen were associated with development of atherosclerosis, thus emphasising the importance of global risk factor control in patients with Type 1 diabetes mellitus.

Cardiac valvular abnormalities are frequent in systemic lupus erythematosus patients with manifest arterial disease

The objective of this study was to study cardiac valve morphology and function and ventricular function in systemic lupus erythematosus (SLE) patients with and without co-existing cardiovascular disease (CVD) and in population controls. Twenty-six women (52 +/- 8.2 years) with SLE (SLE cases) and a history of CVD (angina pectoris, myocardial infarction, cerebral infarction or intermittent claudication) were compared with 26age-matched women with SLE but without manifest CVD (SLE controls) and 26 age-matched control women (population controls). Echocardiographywas performed to assess valvular abnormalities and manifestations of ischaemic heart disease. Thirteen of the 26 SLE cases but only one of the SLE controls and one of the population controls had cardiac valvular abnormalities. Three of the SLE cases had already undergone valve replacement and another had significant aortic insufficiency; the other nine had thickening of mainly mitral leaflets without hemodynamic significance. Among SLE cases, patients with valvular abnormalities had higher homocysteine (P < 0.001) and triglyceride (P = 0.02) concentrations than patients without valvular disease. In contrast atherosclerosis as determined by IMT, oxidized LDL as measured by the monoclonal antibody E06, autoantibodies against epitopes of OxLDL (aOxLDL) or phospholipids (aPL), disease duration or activity, or acute phase reactants did not differ between SLE cases with or without valvular abnormalities. Valvular abnormalities were not more common in SLE cases with stroke as compared to those with myocardial infarction, angina or claudication. In conclusion, valvular abnormalities are strongly associated with CVD in SLE. Raised levels of homocysteine and triglycerides characterize patients with cardiac valve abnormalities.

Gender difference in age-related changes in vascular function

PURPOSE

We investigated whether, in a randomly selected population of 55-year-old men and women, there is a relationship between vascular function measured as flow-mediated (endothelium-dependent) and nitroglycerine-mediated (nonendothelium-dependent) dilatation of the brachial artery and conventional risk factors for cardiovascular disease such as gender, smoking, elevated blood-lipids and high blood pressure. The results are compared with those in a young healthy population of 35-year-olds.

SUBJECTS

A total of 57 men (73% of the invited males) living in the community and 47 women (62% of the invited females) participated and were compared with a previously studied 35-year-old population (52 men and 56 women).

METHODS

Basal brachial artery diameter was measured by high-frequency ultrasound methods. Endothelial function was measured as flow-mediated dilatation (FMD) in response to reactive hyperaemia. The nonendothelium-dependent vasodilatation was measured after administering sublingual nitroglycerine (NTG).

RESULTS

Flow-mediated endothelium-dependent dilatation was similar in men and women being 3.1 +/- 2.5% (mean +/- SD) in men vs. 2.6 +/- 2.3% in women. FMD of the brachial artery was negatively correlated with vessel size in both men and women (P < 0.001). Men had larger brachial artery diameter than women (4.6 +/- 0.7 vs. 3.6 +/- 0.4 mm, P < 0.001). There was no difference in FMD or in NTG-induced dilatation in the women receiving oral oestrogen replacement therapy compared with those that did not. The women taking oral oestrogen had lower cholesterol than those not taking oral oestrogen (P=0.04). FMD was not correlated with any of the risk factors. NTG-induced vasodilatation was correlated with the body mass index (BMI) in men (P=0.01) and a combined risk factor score in women (P=0.04). There was a large increase in the number of subjects with cardiovascular risk factors in the 55-year-old men and women compared with the 35-year-olds. The distribution of risk factors was fairly equal amongst men and women.

CONCLUSION

There are no correlations between any of the conventional cardiovascular risk factors and FMD in a population of 55-year-olds, but there is a high prevalence of risk factors in the 55-year-old age group. NTG-induced vasodilatation correlated with the BMI in men and a combined risk-factor score in women. FMD-induced vasodilatation is smaller in women at 55 years of age than at 35 years of age. FMD was similar in men at 35 and 55 years of age and in men and women at 55 years of age. The smaller FMD in women at 55 years of age, compared with at 35, could be due to postmenopausal hormonal changes.

Association of high resting end tidal CO2 with carotid artery thickness in women, but not men

BACKGROUND

A previous study found high resting end tidal CO2 (PetCO2) to be an independent determinant of systolic blood pressure in women, but not men. The present study investigates the association of PetCO2 with the common carotid artery intima-media thickness (IMT) and wall-to-lumen (W/L) ratio in a sample of normotensive men and women.

DESIGN AND METHODS

Resting PetCO2 of 188 healthy volunteers, including 88 men and 100 women, in the Baltimore Longitudinal Study on Aging was monitored continuously for 25 min via a respiratory gas monitor. At another session, carotid artery IMT was determined via high-resolution B-mode carotid ultrasonography. The ratio of IMT to carotid artery diameter was calculated as W/L ratio. Resting blood pressure was determined oscillometrically every 5 min for 20 min during each session.

RESULTS

Univariate associations of PetCO2 with systolic blood pressure (SBP) (P< 001), IMT (P< 001) and W/L ratio (P< 001) were significant in women, but not men. Multiple regression analyses showed that high resting PetCO2 was a predictor of SBP (P < 01), IMT (P< 01) and W/L ratio (P< 01) in women, independent of age, body mass index and SBP. For men, age (P < 001) and SBP (P < 01) were independent predictors of carotid IMT, while age (P< 001) was the only independent predictor of W/L ratio in men.

CONCLUSIONS

This study indicates that PetCO2 can play a role in cardiovascular structure, as well as function, in women, and that the relationship is independent of the association of PetCO2 with blood pressure.