Factors associated with gender difference in the intima-media thickness of the common carotid artery

Comparison of Carotid Plaque Characteristics Between Men and Women Using Magnetic Resonance Vessel Wall Imaging: A Chinese Atherosclerosis Risk Evaluation Study

BACKGROUND

Carotid vulnerable plaque is a major cause of stroke and differs between men and women. Few studies have investigated the differences in carotid plaque features between sexes in a Chinese population.

PURPOSE

To compare carotid atherosclerotic plaque features between men and women in a Chinese population using magnetic resonance imaging.

STUDY TYPE

Cross-sectional.

SUBJECTS

A total of 567 patients (mean age: 61.5 ± 10.1 years; 404 men) who had recent stroke or transient ischemia attack and atherosclerotic plaque in at least one carotid artery.

FIELD STRENGTH

A 3.0 T.

SEQUENCE

T1- and T2-weighted turbo spin echo, three-dimensional time-of-flight (TOF) fast field echo and magnetization-prepared rapid acquisition gradient echo sequences.

ASSESSMENT

Plaque characteristics including lumen area (LA), wall area (WA), total vessel area (TVA), mean wall thickness (MWT), and mean normalized wall index (NWI); presence of calcification, lipid-rich necrotic core (LRNC), intraplaque hemorrhage (IPH), and fibrous cap rupture (FCR); and percent composition area (%area) were evaluated and compared between men and women.

STATISTICAL TESTS

Independent-sample t test, Mann-Whitney U test, chi-square test, and multiple linear and logistic regressions.

RESULTS

In symptomatic arteries, men had significantly greater LA (46.2 ± 15.6 mm² vs. 40.7 ± 12.9 mm² , P < 0.05), WA (33.9 ± 11.5 mm² vs. 26.3 ± 7.5 mm² , P < 0.05), and TVA (80.1 ± 20.4 mm² vs. 67.0 ± 18.0 mm² , P < 0.05); higher MWT (1.2 ± 0.4 mm vs. 1.0 ± 0.2 mm, P < 0.05); and higher prevalence of LRNC (72.3% vs. 46.0%, P < 0.05) and IPH (18.6% vs. 4.9%, P < 0.05) compared with women. In asymptomatic arteries, men had significantly greater LA (48.3 ± 16.9 mm² vs. 42.1 ± 12.6 mm² , P < 0.05), WA (32.9 ± 11.0 mm² vs. 25.8 ± 6.1 mm² , P < 0.05), and TVA (81.2 ± 22.1 mm² vs. 67.9 ± 16.5 mm² , P < 0.05); higher MWT (1.2 ± 0.3 mm vs. 1.0 ± 0.2 mm, P < 0.05); higher prevalence of LRNC (67.8% vs. 42.9%, P < 0.05), IPH (14.9% vs. 1.2%, P < 0.05), and FCR (6.4% vs. 1.2%, P < 0.05); and higher %LRNC area (24.8 ± 17.2% vs. 17.8 ± 14.1%, P < 0.05) compared with women.

DATA CONCLUSION

Men have similar plaque burden but more vulnerable atherosclerotic plaques compared with women in both symptomatic and asymptomatic carotid arteries in a Chinese population.

EVIDENCE LEVEL

4 TECHNICAL EFFICACY: Stage 3.

Postprandial Apolipoprotein B48 is Associated with Subclinical Atherosclerosis in Patients with Rheumatoid Arthritis

Objective: To describe postprandial lipemia in patients with rheumatoid arthritis (RA) and to analyze its association with subclinical atherosclerosis measured as carotid intima-media thickness (cIMT). Methods: We performed an observational study of 40 patients with RA and 40 sex and age-matched controls. Patients with dyslipidemia were excluded. Pathologically increased cIMT was defined as a carotid thickness greater than the 90th percentile (>p90) for age and sex. Fasting and postprandial plasma lipids, cholesterol, triglycerides, apolipoprotein B48 (ApoB48), and total ApoB were evaluated. The other variables included were clinical and laboratory values, Framingham score, and the 28-joint Disease Activity Score (DAS28). Two multivariate models were constructed to identify factors associated with pathologic cIMT in patients with RA. Results: Fasting lipid values were similar in patients with RA and controls, although those of postprandial ApoB48 were higher (median (IQR), 14.4 (10.8–12.1) vs. 12.1 (2.3–9,8); p = 0.042). Pathologic cIMT was recorded in 10 patients with RA (25%) and nine controls (22.5%). In patients with RA, pathologic cIMT was associated with postprandial ApoB48 (OR (95% CI), 1.15 (1.0–1.3)) and total ApoB (OR [95% CI], 1.12 [1.1–1.2]). The second model revealed a mean increase of 0.256 mm for cIMT in patients with elevated anticitrullinated protein antibodies (ACPAs). Conclusion: Postprandial ApoB48 levels in patients with RA are higher than in controls. Postprandial ApoB48 and total ApoB levels and markers of severity, such as ACPAs, are associated with pathologic cIMT in patients with RA. Our findings could indicate that these atherogenic particles have a negative effect on the endothelium.

Association of carotid intima-media thickness with the risk of sudden sensorineural hearing loss

Cardiovascular factors are associated with the pathophysiological features and risk of sudden sensorineural hearing loss (SSNHL). However, little is known about the link between carotid intima-media thickness (IMT), SSNHL risk, and their respective treatment outcomes. In this study, we retrospectively reviewed 47 SSNHL cases and 33 control subjects from a single medical center and compared their demographic data and clinical characteristics, including their carotid IMT and audiological data. Of the 80 enrolled subjects, the proportion of those with high carotid IMT was greater in the SSNHL group (53.2%) than in the control group (21.2%), with an odds ratio (OR) of 4.22 (95% confidence interval (CI) [1.53–11.61], P = 0.004). Notably, high carotid IMT was more common in female SSNHL patients than females in the control group (54.2% vs. 12.5%; OR, 8.27 (95% CI [1.53–44.62]), P = 0.008), particularly in female patients ≥50 years of age (75% vs. 25%; OR, 9.0 (95% CI [1.27–63.9]), P = 0.032). The multivariate regression analyses showed the association between high carotid IMT and SSNHL with an adjusted OR of 4.655 (95% CI [1.348–16.076], P = 0.015), particularly in female SSNHL patients (adjusted OR, 9.818 (95% CI [1.064–90.587], P = 0.044). The carotid IMT was not associated with the treatment outcomes of SSNHL. Our results indicate that early-stage atherosclerosis may be associated with SSNHL, particularly in female patients more than 50 years old.

The effect of sex and menopause on carotid intima-media thickness and pulse wave velocity in morbid obesity

BACKGROUND

Women are relatively protected from cardiovascular disease compared with men. Since morbid obesity is an independent risk factor for cardiovascular disease, the current study investigated whether the association between sex and cardiovascular risk factors and outcomes can be demonstrated in subjects suffering from morbid obesity.

MATERIALS AND METHODS

Two hundred subjects enrolled in a study on cardiovascular risk factors in morbid obesity underwent extensive laboratory screening, carotid intima-media thickness (cIMT) and pulse wave velocity (PWV) measurements. Gender differences were analysed using univariate and multivariable linear regression models. In addition, the effect of menopause on cIMT and PWV was analysed. Results of these models were reported as B coefficients with 95% confidence intervals.

RESULTS

The group consisted of 52 men and 148 women, with a mean age of 41 (±11.8) years and a mean body mass index (BMI) of 42.7 (±5.2) kg/m² . Both, cIMT and PWV were significantly higher in men than in women, although the difference in cIMT disappeared after adjustment for covariables such as waist circumference, age, high-density lipoprotein cholesterol and mean arterial pressure. PWV was associated with sex after adjustments for covariables in morbidly obese patients. Postmenopausal women had significantly increased cIMT and PWV when compared with premenopausal women.

CONCLUSION

Sex differences in PWV persist in subjects suffering from morbid obesity. However, no difference was found in cIMT between morbidly obese men and women after adjustment for classic cardiovascular risk factors. Premenopausal morbidly obese women are protected for cardiovascular disease when compared with postmenopausal morbidly obese women.

Dietary antioxidant intake decreases carotid intima media thickness in women but not in men: A cross-sectional assessment in the Kardiovize study

OBJECTIVE

Atherosclerosis is a major contributor to cardiovascular disease, with a higher burden on men than women during the occupational age. Intake of individual dietary antioxidants is inversely associated with risk of atherosclerosis development. We aimed to understand the relationship between dietary composite antioxidant intake and the carotid intima media thickness (cIMT), which is a proxy of atherosclerosis progression.

APPROACH AND RESULTS

We performed a cross-sectional analysis that included 894 members of the Kardiovize cohort, a random urban sample population. Nutrient intakes were derived by 24-h recall. We constructed a composite dietary antioxidant index (CDAI), based on zinc, selenium, vitamin A, vitamin C, vitamin E and carotenoids. We considered the CDAI as the exposure variable and primary outcomes were the following cardio-metabolic parameters: body mass index (BMI), waist-to-hip ratio (WHR), body fat mass (BFM), systolic and diastolic blood pressure, triglycerides, HDL and LDL cholesterol, and cIMT. Associations and interactions between variables were evaluated using linear regression analyses. In women, a 1 mg increase in dietary intake of zinc or vitamin E decreased the cIMT by 3.36 and 1.48 µm, respectively, after adjusting for covariates. Similarly, the cIMT decreased by 4.72 µm for each one-unit increase in CDAI (p = 0.018). Beyond CDAI, age (β = 3.61; SE=0.89; p = 0.001), systolic blood pressure (β = 1.30; SE=0.59; p = 0.029) and triglycerides (β = 22.94; SE=10.09; p = 0.024) were significant predictors of cIMT in women. By contrast, we found no association between CDAI and cIMT in men.

CONCLUSIONS

CDAI negatively associates with cIMT in women. These findings indicate that combined intake of nutrients with anti-oxidant properties might prevent the initiation and progression of arterial lesions in a sex-specific manner.

Is there a gender-specific association between asthma and carotid intima media thickness in Swiss adolescents?

Respiratory diseases are associated with increased cardiovascular risk in adults, but little is known on the early impact on the vasculature in youth. The SAPALDIA Youth study, the offspring study of the Swiss Study on Air Pollution and Lung and Heart Disease In Adults (SAPALDIA), investigated the association between physician-diagnosed asthma status and common carotid artery intima media thickness (CIMT). Offspring underwent standardized clinical protocols and provided information on early life factors, health, and lifestyle. The association between per subject averages of CIMT and asthma was estimated using mixed linear regression analyses adjusting for main confounders, testing for interaction with gender and age. Of 257 offspring (mean age 15 years, 53% female), 11.5% reported doctor-diagnosed asthma (male 17%, female 7%). Mean CIMT was significantly different by gender (male 0.53 mm (± 0.045), female 0.50 mm (± 0.048); p < 0.001). Interaction was highly significant by gender (p = 0.001) with significantly increased CIMT in asthmatic vs. non-asthmatics boys (difference 0.023 mm, 95% CI 0.003; 0.043), as compared to girls.

CONCLUSION

Our study suggests an increased risk for early vascular change in adolescent asthmatic boys. Whereas the small number of girls limits the interpretation, the result necessitates further research into sex-specific atherosclerotic burden related to respiratory health in adolescence. What is Known: • Evidence points to a significant impact of adult respiratory disease on cardiovascular health indicators as well as on endpoints. • Inflammation is a key pathway in vascular change across the life course. What is New: • We observe an adverse association between physician-diagnosed asthma and carotid intima media thickness in adolescent boys. • Albeit a limited number of asthmatic girls, we hypothesize the gender typical timing of asthma or a higher male cardiovascular vulnerability as possible explanations for the gender-specific results.

The association between elevated fasting plasma glucose levels and carotid intima-media thickness in non-diabetic adults: a population-based cross-sectional study

We assessed the association between the mean carotid intima-media thickness (CIMT) and fasting plasma glucose (FPG) levels in a low-income population in rural China. Adults aged ≥45 years without a history of diabetes, stroke, or cardiovascular disease were recruited. All participants were categorized into four groups according to FPG level. A total of 3509 participants were analyzed in this study. In the univariate analysis, sex, age, education level, hypertension, central obesity, current smoking, alcohol consumption, and higher levels of FPG, total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were associated with mean CIMT and frequency of increased CIMT. FPG levels were significantly associated with mean CIMT; each 1-mmol/L increase in FPG resulted in a 2.75-μm increase in mean CIMT when adjusted by age, sex, education level, current smoking status, alcohol consumption, hypertension, and the levels of TC, TG, HDL-C, and LDL-C (P = 0.044). However, the association between FPG and the frequency of increased CIMT disappeared after adjusting by covariates. These findings indicate that FPG is an independent determinant of mean CIMT in a non-diabetic population. Management and control of FPG levels is crucial for preventing atherosclerosis in populations with high stroke risks in China.

Muscle fatigue: general understanding and treatment

Muscle fatigue is a common complaint in clinical practice. In humans, muscle fatigue can be defined as exercise-induced decrease in the ability to produce force. Here, to provide a general understanding and describe potential therapies for muscle fatigue, we summarize studies on muscle fatigue, including topics such as the sequence of events observed during force production, in vivo fatigue-site evaluation techniques, diagnostic markers and non-specific but effective treatments.

Increased maximum common carotid intima-media thickness is associated with smoking and hypertension in Tochigi Prefecture residents

OBJECTIVE

We investigated maximum intima-media thickness of the common carotid artery (IMT-C_max) in residents of Tochigi Prefecture, who have been reported to have high stroke mortality.

METHOD

Our study included 840 individuals. All participants underwent carotid ultrasonography and answered a questionnaire during participation in a health festival in Tochigi Prefecture. The questionnaire was designed to collect information on age, gender, and risk factors for stroke. IMT-C_max was measured. Statistical analyses were performed to identify factors contributing to IMT-C_max values ≥1.1 mm.

RESULTS

In total, 117 subjects had an IMT-C_max value ≥1.1 mm. IMT-C_max correlated significantly with age, current smoking, hypertension, diabetes mellitus, heart disease, and previous symptomatic stroke (p < 0.05) in univariate analysis. Current smoking (p < 0.001, odds ratio 3.88) and hypertension (p = 0.0070, odds ratio 1.83) were seen as significant contributing factors to IMT-C_max ≥1.1 mm in logistic regression analysis adjusted by age, gender, and previous symptomatic stroke.

CONCLUSION

We identified current smoking and hypertension as the most significant contributing factors to increased IMT-C_max in residents of Tochigi Prefecture, emphasizing the importance of routine blood pressure monitoring and anti-smoking education in this population.

Features and risk factors of carotid atherosclerosis in a population with high stroke incidence in China

Epidemiological studies have reported associations between traditional cardiovascular risk factors and carotid intima-media thickness (CIMT) or carotid plaque. However, definite risk factors at different phases of carotid atherosclerosis remain controversial. We aimed to explore risk factors and characteristics of carotid atherosclerosis at different stages in a low-income population with a high incidence of stroke in China. Between April 2014 and January 2015, we recruited 3789 stroke-free and cardiovascular disease-free residents aged ≥ 45 years. B-mode ultrasonography was performed to measure CIMT and the presence of carotid plaque. Traditional risk factors were compared between the increased CIMT group and normal CIMT group, and between those with and without carotid plaque. A total of 3789 participants were assessed in this study, with a mean age (standard deviation) of 59.92 (9.70) years. The prevalence of increased CIMT and carotid plaque increased with older age and higher education levels. Age, hypertension, diabetes, and high low-density lipoprotein cholesterol levels were risk factors for increased CIMT and carotid plaque. Furthermore, compared to never smoking, passive smoking was positively associated with increased CIMT, with an odds ratio (95% confidence interval) of 1.26 (1.05, 1.53; P = 0.016); high body mass index was an obvious protective factor against carotid plaque, with an odds ratio (95% confidence interval) of 0.97 (0.95, 0.99; P = 0.004). It is important to identify factors associated with atherosclerosis to prevent cardiovascular disease and stroke and reduce the burden of stroke in this high-risk population.

Impact of inflammation and oxidative stress on carotid intima-media thickness in obstructive sleep apnea patients without metabolic syndrome

Obstructive sleep apnea (OSA) increases the risk of cardiovascular diseases, and carotid intima-media thickness (IMT) is a good indicator of the severity of atherosclerotic disease. This study tested the hypothesis that inflammation and oxidative stress determined carotid IMT in patients with OSA. The carotid IMT, mean systolic and diastolic pressure (night and morning) were significantly higher and the level of thiols and high-density lipoprotein were significantly lower in our 121 OSA patients than in 27 controls (P < 0.05). The apnea/hypopnea index was correlated positively with E-selectin (r = 0.222, P = 0.014), total cholesterol (r = 0.185, P = 0.042), low-density lipoprotein (r = 0.264, P = 0.003) and HbA1c levels (r = 0.304, P = 0.001), but inversely with high-density lipoprotein level (r = -0.203, P = 0.025) in the 121 patients with OSA. In OSA subjects, multiple linear regression analysis revealed that age, systolic blood pressure and intercellular cell adhesion molecule-1 level associated independently with carotid IMT. Besides both age and systolic blood pressure, our study demonstrated that intercellular cell adhesion molecule-1 level was associated significantly with carotid IMT in those patients who had OSA but without metabolic syndrome.

Serum chemerin and high-sensitivity C reactive protein as markers of subclinical atherosclerosis in Egyptian patients with type 2 diabetes

CONTEXT

Chemerin is one of the adipokines that regulate fat metabolism. High-sensitivity C-reactive protein (hs-CRP) may be considered as a cardiovascular risk predictor. Measuring intima-media thickness of the CCA (C-IMT) is a well-evidenced tool for the detection of early stages of atherosclerosis. We aimed here to study both serum chemerin and hs-CRP as markers of subclinical atherosclerosis in Egyptian patients with type 2 diabetes, who are angiographically free of coronary artery disease (CAD).

SUBJECTS AND METHODS

This cross-sectional study was conducted on 180 subjects divided into two groups: Group A included 90 type 2 diabetic patients without CAD and group B including 90 nondiabetic control subjects. All study subjects were having normal coronary angiography. Serum chemerin, homeostasis model assessment for insulin resistance (HOMA-IR), glycated haemoglobin (HbA1c), lipid profile, hs-CRP as well as C-IMT were assessed in all study subjects.

RESULTS

There was a statistically significant difference between the 2 groups regarding serum chemerin level, HOMA-IR, hs-CRP and C-IMT; being higher in the diabetic patients than in the control group (p = 0.006, 0.024, 0.040 and <0.001, respectively). There was positive correlation between serum chemerin level and waist-to-hip ratio (WHR), HOMA-IR, hs-CRP and C-IMT. Carotid intima-media thickness was positively correlated with patients' WHR, blood pressure, HbA1c, diabetes duration as well as hs-CRP, and negatively correlated with ankle-brachial index (ABI). Linear regression analysis showed that HbA1c, serum chemerin and hs-CRP were independently affecting C-IMT. Serum hs-CRP was positively correlated with HbA1c and HOMA-IR (p = 0.006 and 0.032, respectively), and negatively correlated with HDL-cholesterol level (p = 0.018).

CONCLUSION

Both serum chemerin and hs-CRP could be considered as markers of subclinical atherosclerosis, and hence, may be utilized for the early detection of macrovascular disease, in Egyptian patients with type 2 diabetes.

Gender-based differences in the relationship between fatty liver disease and atherosclerosis

Background

Carotid intima–media thickness (CIMT) is a surrogate of subclinical atherosclerosis. Fatty liver disease is also linked to increased risk of cardiovascular events. The aim of this study was to evaluate the association between fatty liver disease and CIMT according to gender.

Methods

Patients who had undergone carotid and abdominal ultrasound between June 2011 and December 2013 were retrospectively evaluated. The differences between the CIMT values measured in the common carotid artery and the prevalence of carotid plaque in patients with fatty liver disease and those with normal livers were investigated.

Results

Out of a total of 1 121 patients, the men had more fatty liver disease than the women. The mean CIMT of the men was significantly higher than that of the women, and the men had more plaque than the women. The women with fatty liver disease had a significantly higher mean CIMT value and more plaque than the women with normal livers. The differences between the men with fatty liver and those with normal livers in mean CIMT values and in the prevalence of plaque were not significant. In the women, multivariate analysis showed that fatty liver disease was independently associated with subclinical atherosclerosis [adjusted hazards ratio (HR) 1.65, 95% confidence interval (CI) 1.007–2.697, p = 0.047].

Conclusions

The men had more fatty liver disease, carotid plaque and higher CIMT values than the women. Fatty liver disease was a useful predictor of atherosclerosis, especially for the female study patients.

Carotid Intima Media Thickness Is Independently Associated with Male Gender, Middle Age, and IGF-1 in Metabolically Healthy Obese Individuals

Background/Aims. The effect of benign obesity on subclinical cardiovascular disease is still questionable. The purpose of this study was to assess carotid intima media thickness (CIMT), as a marker of subclinical atherosclerosis, and to evaluate its relation to age, sex, and IGF-1 in metabolically healthy obese (MHO) subjects. Methods. A total of 75 MHO subjects and 80 age, and sex matched healthy nonobese control subjects were included in the study. Body mass index (BMI), waist circumference (WC), blood pressure, fasting plasma glucose, fasting insulin, HOMA-IR, lipid profile, insulin like growth factor-1 (IGF-1), and CIMT were assessed in all subjects. Results. MHO subjects had significantly higher CIMT and lower IGF-1 than healthy nonobese controls. Mean CIMT was significantly higher in MHO men age subgroup range from 30 to 50 years than in their age range matched (premenopausal) MHO women subgroup. In MHO subjects, CIMT was positively correlated with age, BMI, WC, SBP, HOMA-IR, TG, and LDL-C, and negatively correlated with IGF-1. Regression analysis revealed that middle age, male sex and IGF-1 remained independently associated with CIMT in MHO subjects. Conclusion. CIMT is elevated and IGF-1 is reduced in MHO subjects, and CIMT is independently associated with male gender, middle age, and IGF-1. Definition of healthy obesity may be broadened to include IMT measurement.

Long-term effects on carotid intima-media thickness after radiotherapy in patients with nasopharyngeal carcinoma

Background

Vascular abnormalities are the predominant histologic changes associated with radiation in nasopharyngeal carcinoma (NPC). This study examined if the duration after radiotherapy correlates with the progression of carotid intima-media thickness (IMT) and investigated its relationship with inflammatory markers.

Methods

One hundred and five NPC patients post-radiotherapy for more than one year and 25 healthy control subjects were examined by B-mode ultrasound for IMT measurement at the far wall of the common carotid artery (CCA). Surrogate markers including lipid profile, HbA1c, and high sensitive C-reactive protein (hs-CRP) were assessed.

Results

The IMT of CCA was significantly increased in NPC patients and carotid plaque was detected in 38 NPC patients (38/105, 36.2%). Significant risk factors for carotid plaques included age, duration after radiotherapy, and HbA1c levels. Age, duration after radiotherapy, hs-CRP, HbA1c, and platelet count positively correlated with IMT. The cut-off value of age and duration after radiotherapy for the presence of plaque was 52.5 years and 42.5 months, respectively. In NPC subjects, multiple linear regression analysis revealed that age, gender, duration after radiotherapy and platelet counts were independently associated with CCA IMT. After adjustments for age, gender and platelet counts, IMT increased in a linear manner with duration after radiotherapy.

Conclusions

Radiation-induced vasculopathy is a dynamic and progressive process due to late radiation effects. Extra-cranial color-coded duplex sonography can be part of routine follow-up in NPC patients aged ≥50 years at 40 months post-radiotherapy.

Traditional risk factors are not major contributors to the variance in carotid intima-media thickness

BACKGROUND AND PURPOSE

Carotid intima-media thickness (cIMT) was a widely accepted ultrasound marker of subclinical atherosclerosis in the past. Although traditional risk factors may explain ≈50% of the variance in plaque burden, they may not explain such a high proportion of the variance in IMT, especially when measured in plaque-freel ocations. We aimed this study to identify individuals with cIMT unexplained by traditional risk factors for future environmental and genetic research.

METHODS

As part of the Northern Manhattan Study, 1790 stroke-free individuals (mean age, 69±9 years; 60% women; 61% Hispanic; 19% black; 18% white) were assessed for cIMT using B-mode carotid ultrasound. Multiple linear regression models were evaluated: (1) incorporating prespecified traditional risk factors; and (2) including less traditional factors, such as inflammation biomarkers, adiponectin, homocysteine, and kidney function. Standardized cIMT residual scores were constructed to select individuals with unexplained cIMT.

RESULTS

Mean total cIMT was 0.92±0.09 mm. The traditional model explained 11% of the variance in cIMT. Age (7%), male sex (3%), glucose (<1%), pack-years of smoking (<1%), and low-density lipoprotein cholesterol (<1%) were significant contributing factors. The model, including inflammatory biomarkers, explained 16% of the variance in cIMT. Adiponectin was the only additional significant contributor to the variance in cIMT. We identified 358 individuals (20%) with cIMT unexplained by the investigated risk factors.

CONCLUSIONS

Vascular risk factors explain only a small proportion of variance in cIMT. Identification of novel genetic and environmental factors underlying unexplained subclinical atherosclerosis is of utmost importance for future effective prevention of vascular disease.

Factors associated with increased carotid intima-media thickness in obstructive sleep apnea/hypopnea syndrome

BACKGROUND

Obstructive sleep apnea/hypopnea syndrome (OSAHS) is strongly associated with the increase of cardiovascular and cerebrovascular disorders. Carotid intima-media thickness (IMT) is used as a surrogate marker for subclinical or early atherosclerosis. Knowledge regarding early atherosclerosis in patients with OSAHS is scarce, and factors predicting carotid IMT have not been well studied.

OBJECTIVE

To compare IMT in patients with OSAHS versus controls and explore the factors associated with increased IMT in OSAHS.

METHODS

One hundred fifty-six OSAHS patients and 35 controls without history of vascular events, hypertension, and diabetes mellitus who underwent polysomnography were consecutively enrolled. Carotid IMT was measured using B-mode ultrasonography. Body mass index, waist circumference, hip circumference, waist-to-hip circumference ratio, Epworth Sleepiness Scale, and polysomnographic variables including arousal index, apnea/hypopnea index, mean oxygen saturation, and lowest oxygen saturation were assessed. Fasting plasma glucose, blood lipid profile, and high-sensitivity C-reactive protein were measured.

RESULTS

Average carotid IMT of OSAHS patients was significantly thicker than controls (0.66 vs. 0.58 mm, P=0.002) and multivariable logistic regression analysis revealed that arousal index [odds ratio (OR), 0.77; confidence interval (CI), 0.63-0.95; P=0.01] and lowest oxygen saturation (OR, 1.91; CI, 1.24-2.95; P=0.003) were significantly associated with OSAHS patients. Among the OSAHS patients, age (OR, 1.16; CI, 1.10-1.22; P<0.0001), fasting plasma glucose (OR, 1.05; CI, 1.01-1.10; P=0.04), low-density lipoprotein cholesterol (OR, 1.03; CI, 1.02-1.05; P<0.0001), and high-sensitivity C-reactive protein (OR, 1.48; CI, 1.13-1.95; P=0.005) were significantly associated with patients with IMT≥0.65 mm.

CONCLUSIONS

IMT was thicker in OSAHS patients without history of vascular events, hypertension, and diabetes mellitus. This study demonstrates that early atherosclerosis exists in this group of patients.

Long-term effects of neck irradiation on cardiovascular autonomic function: a study in nasopharyngeal carcinoma patients after radiotherapy

INTRODUCTION

Baroreflex failure has been reported as a late sequalum of neck radiotherapy. In this study we investigated cardiovascular autonomic function in patients after neck radiotherapy to determine predictive factors associated with outcome.

METHODS

Eighty-nine patients with nasopharyngeal carcinoma were evaluated ≥6 months after radiotherapy for cardiovascular autonomic function and compared with 48 control subjects. Inflammatory markers and carotid intima-media thickness were also assessed.

RESULTS

Autonomic parameters of heart rate response to deep breathing and Valsalva ratio were significantly lower in the patient group. Cardiovascular autonomic impairment was generally mild with relative sparing of the efferent cardiovagal pathway. By univariate and multivariate analyses, the time after radiotherapy and C-reactive protein level were significantly associated with the degree of cardiovascular autonomic dysfunction.

CONCLUSIONS

Radiation-induced cardiovascular autonomic impairment is a dynamic and progressive process that occurs long after radiotherapy. Chronic inflammation plays a major role in this process.

Gender-specific differences in carotid intima-media thickness and its progression over three years: a multicenter European study

BACKGROUND AND AIMS

This multicentre European study evaluated, in a young-to-middle-aged healthy population without carotid atherosclerosis, the gender-related differences in carotid intima-media thickness (IMT) and its short-term (3-year) progression, and whether these differences are related to different vascular ageing rate, cardiovascular risk profile or different susceptibility to family predisposition to cardiovascular diseases (CVD).

METHODS AND RESULTS

366 men and 422 women (age between 30 and 60 years) underwent B-mode carotid ultrasound at baseline and after 3-year follow-up period. IMT in 3 carotid segments was higher in men than in women (p < 0.0001 for all segments). When evaluated according to age decade, differences between men and women disappeared in the 6th decade, as in this decade a 3-year IMT progression rate accelerated in women (p < 0.05 as compared to the 4th and 5th age decade). Age was a major determinant of baseline all-segment IMT in women; in men all-segment IMT was influenced by age and LDL-cholesterol. IMT progression did not correlate with established cardiovascular risk factors, their short-term changes or family predisposition to CVD. Yet, a 3-year IMT progression in common carotid artery (CCA) was higher in men (p = 0.01) and women (p < 0.01) in whom relative Framingham risk increased during the corresponding period.

CONCLUSION

This study provides reference values on IMT and its short-term progression in healthy young-to-middle-aged population, and demonstrates gender-related differences in the susceptibility of carotid wall to ageing and LDL-cholesterol. Increase in Framingham risk accelerated a short-term CCA IMT progression rate in both genders, whereas family predisposition to CVD did not influence carotid IMT.

Biomarkers of peripheral muscle fatigue during exercise

BACKGROUND

Biomarkers of peripheral muscle fatigue (BPMFs) are used to offer insights into mechanisms of exhaustion during exercise in order to detect abnormal fatigue or to detect defective metabolic pathways. This review aims at describing recent advances and future perspectives concerning the most important biomarkers of muscle fatigue during exercise.

RESULTS

BPMFs are classified according to the mechanism of fatigue related to adenosine-triphosphate-metabolism, acidosis, or oxidative-metabolism. Muscle fatigue is also related to an immunological response. impaired calcium handling, disturbances in bioenergetic pathways, and genetic responses. The immunological and genetic response may make the muscle susceptible to fatigue but may not directly cause muscle fatigue. Production of BPMFs is predominantly dependent on the type of exercise. BPMFs need to change as a function of the process being monitored, be stable without appreciable diurnal variations, correlate well with exercise intensity, and be present in detectable amounts in easily accessible biological fluids. The most well-known BPMFs are serum lactate and interleukin-6. The most widely applied clinical application is screening for defective oxidative metabolism in mitochondrial disorders by means of the lactate stress test. The clinical relevance of most other BPMFs, however, is under debate, since they often depend on age, gender, physical fitness, the energy supply during exercise, the type of exercise needed to produce the BPMF, and whether healthy or diseased subjects are investigated.

CONCLUSIONS

Though the role of BPMFs during fatigue is poorly understood, measuring BPMFs under specific, standardised conditions appears to be helpful for assessing biological states or processes during exercise and fatigue.

Age- and gender-associated determinants of carotid intima-media thickness: a community-based study

AIM

Few population-based studies have assessed the risk factors of and gender differences in intima-media thickness (IMT) at the common carotid artery (CCA) for different age groups.

OBJECTIVE

Factors determining age and gender differences in IMT were studied in ethnic Chinese participants of the Chin-Shan Community Cardiovascular Cohort in Taiwan.

METHODS

From July 1994 through August 1996, the CCA-IMT of 1203 men and 1487 women aged 35 years or more was measured using high-resolution B-mode carotid ultrasound. Cardiovascular risk factors were recorded for each subject.

RESULTS

The CCA-IMT consistently increased with age and was more in men than in women. For participants aged 55 years or more, women showed a more rapid increase in systolic blood pressure (SBP) and low-density lipoprotein cholesterol (LDL) than men. The gender difference in CCA-IMT became insignificant after 75 years of age. The major determinants of CCA-IMT in addition to age and gender were body mass index at 35-44 years of age, LDL in both genders and SBP in women at 45-54 years old, SBP at 55-64 and 65-74 years old, and women with left ventricular hypertrophy, hypertension with medication, and high LDL levels at 65-74 years old after multivariate linear regression analysis. For those aged over 75 years, SBP was an important determinant of CCA-IMT.

CONCLUSIONS

The CCA-IMT increases with age and its determinants are associated with age and gender. The rapid increase in cardiovascular risk factors in women after 55 years of age attenuates the female advantage in CCA-IMT.

Gender difference in carotid intima-media thickness in type 2 diabetic patients: a 4-year follow-up study

Background

Different population studies have reported gender difference in carotid intima-media thickness (CIMT), which is proved to be a risk factor of cardiovascular diseases. However, few longitudinal researches examine this gender difference in type 2 diabetes mellitus (T2DM) patients. Therefore, we prospectively analyzed CIMT in T2DM patients over a 4-year follow-up period.

Methods

355 T2DM patients (mean age 59 years; 54.9% women) were included in the present study. CIMT were measured using Color Doppler ultrasound. CIMT was measured at baseline (CIMT) in 2006 and at follow-up in 2010. Biochemical and clinical measurements were collected at baseline.

Results

Mean value of CIMT1 and CIMT2 were 0.740 ± 0.148 mm and 0.842 ± 0.179 mm, respectively. Men had higher CIMT than women both at baseline and at follow-up (CIMT1: 0.762 ± 0.149 vs 0.723 ± 0.146 mm, P = 0.0149; CIMT2: 0.880 ± 0.189 vs 0.810 ± 0.164 mm, P = 0.0002). Mean annual progression of CIMT (dCIMT) was 0.025 ± 0.022 mm/year. dCIMT was larger in men than in women (0.030 ± 0.025 vs 0.022 ± 0.019 mm, P = 0.0006). In multiple regression analyses, age was an independent risk factor of CIMT in both genders, while dCIMT was associated with age only in men.

Conclusions

Gender difference in CIMT was confirmed in T2DM patients. Moreover, impact of ageing on CIMT progression only existed in men, which might be the reason that gender difference in CIMT increased with age.

Analysis of femoral artery intima-media thickness during the cardiac cycle

BACKGROUND

Variations in the intima-media thickness (IMT) of the carotid artery during the cardiac cycle are well established. The change in femoral IMT during the cardiac cycle is largely unknown. This study focuses on the variation of femoral IMT, vessel diameter, and cross-sectional area (CSA) of the IMT during the cardiac cycle.

METHODS

Video clips of the femoral artery were obtained using B-mode ultrasonography in 60 patients between the ages of 18 and 50. IMT and diameter measurements were made using automated software, and CSA was subsequently calculated. Triplicate measurements of each femoral artery were made at three points in the cardiac cycle: the R wave, the T wave, and at the point of maximal vessel diameter falling after the T wave and before the following P wave.

RESULTS

Femoral IMT, diameter, and CSA did not show a statistically significant difference with measurement on the R versus the T wave (P>0.36, P>0.28, and P>0.76, respectively). Interestingly, when comparing measurements on the R or T wave with measurements taken at the maximum vessel diameter, there was a statistically significant difference in vessel diameter (P<0.001) and CSA (P<0.005) but not in femoral IMT (P>0.2).

CONCLUSIONS

Unlike studies of the carotid artery, there were no statistically significant differences between measurements made at the R versus the T wave. There were, however, statistically significant differences noted in diameter and CSA when measurements were taken at a point later in the cardiac cycle. This has ramifications for future studies on vascular remodeling.

Carotid artery intima-media thickness in college students: race/ethnicity matters

OBJECTIVE

Racial/ethnic differences in common carotid artery intima-media thickness (CIMT) and in risk factors associated with CIMT have been predominantly observed in middle-aged and older individuals. We aimed to characterize racial/ethnic differences CIMT and other cardiovascular risk factors in a healthy, young-adult population.

METHODS

College students were recruited as part of a study to characterize determinants of atherogenesis. Students were eligible if they were lifetime non-smokers, lived in the United States since six months of age, and attended high school in the United States. Blood pressure, heart rate, height, and weight were measured, B-mode carotid ultrasound was performed, questionnaires were administered and a 12-h fasting blood sample was collected. Associations between CIMT and other variables were assessed in 768 students aged 18-25 years using linear regression analysis.

RESULTS

In models adjusted for common cardiovascular risk factors, sex exhibited the strongest influence on CIMT, with men having 15.4 μm larger CIMT compared to women (95%CI 6.6, 24.2). Race/ethnicity was also strongly associated with CIMT. African Americans had 17.3 μm greater CIMT (95%CI -0.3, 34.8) compared to non Hispanic Whites, whereas Asians and Hispanic Whites had 14.3 (95%CI -24.3, -4.4) and 15.4 (95%CI -26.2, -4.7) μm smaller CIMT, respectively. BMI and systolic blood pressure were positively associated with CIMT.

CONCLUSION

The risk factors associated with atherogenesis later in life are already present and observable in college-aged young adults, so targeted campaigns to reduce life-long cardiovascular disease burden should be initiated earlier in life to improve public health.

Determinants of vascular function in patients with chronic gout

Epidemiologic studies have proposed a relationship between hyperuricemia and cardiovascular (CV) risk. However, it is unclear whether uric acid (UA) is an independent risk factor for CV disease (CVD) after controlling for other predisposing conditions. Gout patients might have persistent systemic inflammation, which, in addition to hyperuricemia, may potentiate CVD. This study examined vascular function and markers of CV damage in gout patients when compared with healthy controls. Brachial artery flow-mediated dilatation, arterial compliance, and microvascular function were measured. Circulating apoptotic endothelial cells and endothelial progenitor cells were quantified by FACS and circulating biomarkers of CVD by enzyme-linked immunosorbent assay. Gout patients displayed significant increases in body mass index, C-reactive protein, UA, and triglycerides and decreases in high-density lipoprotein. There were no significant differences in other CV traditional risk factors, adhesion molecules, or chemokines. Gout patients did not differ from controls in vascular function. In univariate and multivariate analysis, UA was not associated with the quantified CV risk parameters. Despite an increase in several CV risk factors, inflammation, and UA, gout patients display normal endothelial function and no increases in biomarkers of CVD. These results do not support the notion that gout is an independent risk factor for premature CVD.