Smoking cessation and carotid atherosclerosis: the Guangzhou Biobank Cohort Study--CVD

Risk factors and prediction model of nomogram for preoperative calf muscle vein thrombosis in geriatric hip fracture patients

Introduction

Calf muscular vein thrombosis (CMVT) is a common complication in geriatric hip fracture patients. Despite its high incidence, prior research on the topic is limited. The occurrence of CMVT in patients will prolong the preoperative waiting time and even lead to serious thromboembolic events, which can be detrimental to the patient's prognosis. Therefore, this study aimed to identify the risk factors for preoperative CMVT in geriatric hip fracture patients and construct a nomogram model to predict the risk of preoperative CMVT in patients.

Materials and methods

Geriatric hip fracture patients who underwent surgery between January 2019 and January 2022 were included. The patients were categorized into two groups depending on whether they had preoperative CMVT, confirmed through Color Doppler ultrasound or venography examination. Univariate and multivariate logistic regression analyses were used to analyze demographic characteristics, medical history, comorbidities, and laboratory tests. A nomogram was constructed to predict preoperative CMVT in geriatric hip fracture patients based on the results of the multivariate logistic regression.

Results

Three hundred and eighty-eight geriatric hip fracture patients, including one hundred and thirty-four patients with CMVT and two hundred and fifty-four patients without CMVT, were ultimately included in our study. After multivariable logistic regression analysis, the time from injury to admission, smoking history, serum albumin levels, and D-dimer levels was identified as independent risk factors and was entered into a nomogram model. The nomogram showed robust discrimination, with an area under the receiver operating characteristic curve of 0.805. The calibration curve showed strong agreement between the CMVT probabilities predicted by the nomogram and the actual probabilities. The decision curve analysis illustrates the excellent clinical utility of the model.

Conclusion

We have constructed a new nomogram prediction model that can effectively predict the risk of preoperative CMVT in geriatric hip fracture patients based on their medical history and blood test results. This model can help clinicians make individualized predictions of CMVT that are tailored to each patient's unique circumstances.

Cumulative tobacco consumption has a dose-dependent effect on atheromatosis burden and improves severe atheromatosis prediction in asymptomatic middle-aged individuals: The ILERVAS study

BACKGROUND AND AIMS

Sex-specific impact of cumulative tobacco consumption (CTC) on atheromatosis extension and total plaque area remains unknown. We aimed to determine the impact of CTC in atheromatosis localization and burden.

METHODS

We performed a cross-sectional analysis in 8330 asymptomatic middle-aged individuals. 12-territory vascular ultrasounds in carotid and femoral arteries were performed to detect atheromatous plaque presence and to measure total plaque area. Adjusted regressions and conditional predictions by smoking habit or CTC (stratified in terciles as low (≤13.53), medium (13.54-29.3), and high (>29.3 packs-year)) were calculated. Severe atheromatosis (SA, ≥3 territories with atheroma plaque) was predicted with the Systematic COronary Risk Evaluation 2 (SCORE2) model. The improvement of SA prediction after adding CTC was evaluated.

RESULTS

CTC was associated with an increased risk of atheromatosis, stronger in femoral than in carotid artery, but similar in both sexes. A dose-dependent effect of CTC on the number of territories with atheroma plaque and total plaque area was observed. Addition of CTC to the SCORE2 showed a higher sensitivity, accuracy, and negative predictive value in males, and a higher specificity and positive predictive value in females. In both sexes, the new SCORE2-CTC model showed a significant increase in AUC (males: 0.033, females: 0.038), and in the integrated discrimination index (males: 0.072; females: 0.058, p < 0.001). Age and CTC were the most important clinical predictors of SA in both sexes.

CONCLUSIONS

CTC shows a dose-dependent association with atheromatosis burden, impacts more strongly in femoral arteries, and improves SA prediction.

Disturbed Ratios between Essential and Toxic Trace Elements as Potential Biomarkers of Acute Ischemic Stroke

Background: Cadmium (Cd) and lead (Pb) are known to be two of the metal contaminants that pose the greatest potential threat to human health. The purpose of this research study was to compare the levels of toxic metals (Cd, Pb) in patients with acute ischemic stroke (AIS), with a control group in Podlaskie Voivodeship, Poland. The study also aimed to assess the correlations between toxic metals and clinical data in AIS patients, and to assess the potential effect of smoking. Materials and methods: The levels of mineral components in the collected blood samples were assessed by means of atomic absorption spectrometry (AAS). Results: The Cd blood concentration was significantly higher in AIS patients as compared to the control group. We found that the molar ratios of Cd/Zn and Cd/Pb were significantly higher (p < 0.001; p < 0.001, respectively), when the molar ratios of Se/Pb, Se/Cd, and Cu/Cd were significantly lower (p = 0.01; p < 0.001; p < 0.001, respectively), in AIS patients as compared to control subjects. However, there were no considerable fluctuations in relation to the blood Pb concentration or molar ratios of Zn/Pb and Cu/Pb between our AIS patients and the control group. We also found that patients with internal carotid artery (ICA) atherosclerosis, particularly those with 20–50% ICA stenosis, had higher concentrations of Cd and Cd/Zn, but lower Cu/Cd and Se/Cd molar ratios. In the course of our analysis, we observed that current smokers among AIS patients had significantly higher blood-Cd concentrations, Cd/Zn and Cd/Pb molar ratios, and hemoglobin levels, but significantly lower HDL-C concentrations, Se/Cd, and Cu/Cd molar ratios. Conclusions: Our research has shown that the disruption of the metal balance plays a crucial role in the pathogenesis of AIS. Furthermore, our results broaden those of previous studies on the exposure to Cd and Pb as risk factors for AIS. Further investigations are necessary to examine the probable mechanisms of Cd and Pb in the onset of ischemic stroke. The Cd/Zn molar ratio may be a useful biomarker of atherosclerosis in AIS patients. An accurate assessment of changes in the molar ratios of essential and toxic trace elements could serve as a valuable indicator of the nutritional status and levels of oxidative stress in AIS patients. It is critical to investigate the potential role of exposure to metal mixtures in AIS, due to its public health implications.

The Impact of Dietary Diversity, Lifestyle, and Blood Lipids on Carotid Atherosclerosis: A Cross-Sectional Study

Carotid atherosclerosis is a common arterial wall lesion that causes narrowing and occlusion of the arteries and is the basis of cardiovascular events. Dietary habits, lifestyle, and lipid metabolism should be considered integrally in the context of carotid atherosclerosis (CAS). However, this area has been investigated less often in China. To understand the prevalence of CAS in China and the impact of dietary diversity and habits, lifestyle, and lipid metabolism on CAS as well as its predictive factors, a cross-sectional study was performed in two northern and southern Chinese tertiary hospitals from 2017 to 2019. Included participants underwent carotid artery color Doppler ultrasonography, blood lipid examination and dietary evaluation. In total, 11,601 CAS patients and 27,041 individuals without carotid artery lesions were included. The prevalence of CAS was 30.0% in this group. High BMI (OR: 1.685, 95% CI [1.315-2.160]), current (1.148 [1.077-1.224]) or ex-smoking (1.349 [1.190-1.529]), abstinence from alcohol ((1.223 [1.026-1.459]), social engagement (1.122 [1.050-1.198]), hypertension (1.828 [1.718-1.945]), and total cholesterol (1.438 [1.298-1.594]) were risk factors for CAS, while higher dietary diversity according to DDS-2 (0.891 [0.805-0.989]), HDL-C (0.558 [0.487-0.639]), sugar-sweetened beverages (0.734 [0.696-0.774]), and no midnight snack consumption (0.846 [0.792-0.903]) were protective factors. This current study demonstrated that higher dietary diversity was a protective factor against CAS in a healthy population. In addition, current recommendations of healthy lifestyle and dietary habits for preventing CAS should be strengthened. In addition, dietary diversity should concentrate on food attributes and dietary balance, rather than increased quantities.

Optimal Medical Management of Asymptomatic Carotid Stenosis

Asymptomatic carotid stenosis (ACS) due to atherosclerosis is a risk factor for ipsilateral ischemic cerebrovascular events and cognitive impairment. The prognosis of ACS has improved over the past 4 decades due largely to improvements in medical management. Most patients with ACS can be managed without revascularization, but some patients with vulnerable plaque should be considered for revascularization. Regardless of the decision to refer for revascularization, all patients with ACS should receive intensive medical management. This includes lifestyle modification (Mediterranean diet, exercise, and smoking cessation) and pharmacological therapy (antiplatelets, lipid-lowering agents, blood pressure reduction, and glycemic control). Patients with ACS often have atherosclerosis in other critical locations, and thus optimal medical therapy is likely to reduce events outside the carotid arteries. The nature of optimal medical therapy is described.

Global and regional prevalence, burden, and risk factors for carotid atherosclerosis: a systematic review, meta-analysis, and modelling study

BACKGROUND

Estimation of the epidemiological burden of carotid atherosclerosis can serve as a basis for prevention and management of cardiovascular disease. We aimed to provide the first estimation on the prevalence, number of cases, and risk factors for carotid atherosclerosis in the general population globally and regionally.

METHODS

In this systematic review, meta-analysis, and modelling study, we searched PubMed, MEDLINE, Embase, Global Health, and China National Knowledge Infrastructure for articles published from database inception until May 7, 2019, with no language restrictions, for population-based studies that quantified prevalence of carotid atherosclerosis by means of increased carotid intima-media thickness, carotid plaque, and carotid stenosis. Studies were eligible if they included bilaterally scanned carotid arteries using ultrasonography and defined increased carotid intima-media thickness as a thickness of 1·0 mm or more, carotid plaque as a focal carotid intima-media thickness of 1·5 mm or more encroaching into the lumen or at least 0·5 mm or 50% compared with the surrounding carotid intima-media thickness values, and carotid stenosis as 50% or more stenosis. Studies were excluded if the sample was not representative of the general population. We also included studies identified in our previous systematic review and meta-analysis of the prevalence of carotid atherosclerosis in China. We estimated age-specific and sex-specific prevalences of increased carotid intima-media thickness, carotid plaque, and carotid stenosis. We used UN population data to generate the number of people affected in 2000, 2015, and 2020. We did random-effects meta-analyses to assess the effects of risk factors for increased carotid intima-media thickness and carotid plaque. We derived regional numbers of people living with increased carotid intima-media thickness and carotid plaque in 2015 using a risk factors-based model by WHO region. All analyses were done in populations aged 30-79 years due to availability of data. This systematic review and meta-analysis is registered online on PROSPERO, CRD42019134709.

FINDINGS

We identified 8632 articles through our database search, of which 515 were eligible for full-text review, including 37 articles from our previous study, and 59 articles were eligible for inclusion in our systematic review and meta-analysis. Overall, in people aged 30-79 years in 2020, the global prevalence of increased carotid intima-media thickness is estimated to be 27·6% (95% CI 16·9-41·3), equivalent to 1066·70 million affected people and a percentage change of 57·46% from 2000; of carotid plaque is estimated to be 21·1% (13·2-31·5), equivalent to 815·76 million affected people and a percentage change of 58·97% from 2000; and carotid stenosis is estimated to be 1·5% (1·1-2·1), equivalent to 57·79 million affected people and a percentage change of 59·13% from 2000. The prevalence of increased carotid intima-media thickness, carotid plaque, and carotid stenosis increased consistently with age and was higher in men than in women. Current smoking, diabetes, and hypertension were common risk factors for increased carotid intima-media thickness and carotid plaque. In 2015, the Western Pacific region had the largest share of global cases of increased carotid intima-media thickness (317·62 million [33·36%] of 952·13 million affected people) and carotid plaque (240·77 million [33·20%] of 725·25 million), whereas the African region had the smallest share of cases of increased carotid intima-media thickness (59·08 million [6·21%]) and the Eastern Mediterranean region had the smallest share of carotid plaque cases (44·59 million [6·15%]).

INTERPRETATION

A substantial global burden of carotid atherosclerosis exists. Effective strategies are needed for primary prevention and management of carotid atherosclerosis. High-quality epidemiological investigations on carotid atherosclerosis are needed to better address the global burden of carotid atherosclerosis at finer levels.

FUNDING

None.

The mediating role of inflammation in the association between cigarette smoking and intima-media thickness: The Guangzhou biobank cohort study

Cigarette smoking is associated with thicker carotid intima-media thickness (IMT), probably partly through inflammatory pathways. However, to what extent does inflammation mediate the smoking-carotid atherosclerosis association is unclear. We investigated the mediating effect of inflammation on the association between cigarette smoking and carotid IMT, and quantified the respective contributions of inflammatory markers to this association.A total of 1752 participants from Guangzhou Biobank Cohort Study-Cardiovascular Disease Sub-cohort (GBCS-CVD) were included. Using causal mediation analysis under the counterfactual framework, we decomposed total effects of cigarette smoking on IMT into indirect effects (through inflammatory response) and direct effects (not through inflammatory response).After adjusting for traditional risk factors, the indirect effects of per 10/L increment in leukocyte and granulocyte, per mg/L increment in high-sensitivity C-reactive protein (hs-CRP), and per mg/dL increment in fibrinogen on carotid IMT was 0.0028 mm (95% confidence interval [CI], 0.0011-0.0047), 0.0019 mm (95% CI, 0.0006-0.0034), 0.0017 mm (95% CI, 0.0006-0.003), and 0.001 mm (95% CI, 0.0001-0.0021), respectively. No evidence for a mediating role of lymphocyte was found. The proportion of the smoking-IMT association mediated by leukocyte, granulocyte, hs-CRP, and fibrinogen was 12.57% (95% CI, 8.50%-22.11%), 8.50% (95% CI, 5.76%-15.09%), 7.64% (95% CI, 5.20%-13.79%), and 4.48% (95% CI, 3.04%-8.03%), respectively. Restricting data analysis to men showed similar results.The effects of cigarette smoking on IMT were partly mediated by leukocyte, hs-CRP, and fibrinogen. The mediating role of leukocyte was likely mainly driven by higher granulocyte.

Adolescence benzo[a]pyrene treatment induces learning and memory impairment and anxiolytic like behavioral response altering neuronal morphology of hippocampus in adult male Wistar rats

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Intraperitoneal B[a]P administration induces anxiolytic like behavior in rats.

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B[a]P induces oxidative stress and reduces antioxidant enzyme activity.

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Exposure to B[a]P-induces decrease in dendrite length and spine density through oxidative stress affecting antioxidant defence system.

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Alteration in the neuronal architecture of the hippocampal cells after B[a]P administration is associated with learning and memory defict.

Exposure to benzo[a]pyrene (B[a]P), a prototype of polycyclic aromatic hydrocarbons (PAHs) easily cross blood brain barrier (BBB) and is associated with impaired learning and memory in adult rats. However, there is no symmetric study reported on association between B[a]P exposure during the early development and hippocampal dendritic architecture causing behavioral changes like learning and memory deficit of adult rats. We investigated a fourteen day consecutive B[a]P administration, intraperitonial (i.p.), with two different doses (0.1 and 1μM) during early adolescence at PND30-44 and learning behavior assessed between PND 45-60 in adult male rats. The anxiolytic like behavioural analysis was done by LDPT. Depressive like behaviour was estimated through sucrose preference and learning and memory by T-maze. After B[a]P administration oxidative stress markers like glutathione S-transferase (GST), glutathione reductase (GR), glutathione peroxidase (GPx), reduced (GSH) and oxidized glutathione (GSSG) were evaluated. To parallel these behavioral and antioxidant level changes to alteration in dendritic morphology, Golgi-Cox staining was performed in the hippocampus. Our study showed anxiolytic like behavioral response with significant increase in time spent in light zone and significant (p < 0.05) decrease in preference for sucrose and a reduction in percentage of spontaneous responses in T-maze test in B[a]P administered group as compared to vehicle control. B[a]P exposed male rats showed significant increase in GST activity (p < 0.05) and concentration of GSSG with a decay in GSH, GPx and GR in both the groups as compared to control. B[a]P administered rats showed significant loss in total dendritic length and number (28%) with reduced spine density (18%) in both higher and lower doses. These results suggested that B[a]P administration can be associated with an increase ROS production showing altered antioxidant defence system through glutathione biosynthesis and causing profound alterations in dendritic length and spine density of hippocampal neurons leading towards learning and memory deficits in adult rats.

Assessment of the Role of Carotid Atherosclerosis in the Association Between Major Cardiovascular Risk Factors and Ischemic Stroke Subtypes

IMPORTANCE

A better understanding of the role of atherosclerosis in the development of ischemic stroke subtypes could help to improve strategies for prevention of stroke worldwide.

OBJECTIVE

To assess the role of carotid atherosclerosis in the association between major cardiovascular risk factors and ischemic stroke subtypes.

DESIGN, SETTING, AND PARTICIPANTS

The prospective China Kadoorie Biobank cohort study was conducted in the general population of 5 urban and 5 rural areas in China, with a baseline survey obtained between June 2004 and July 2008. A random sample of 23 973 participants with no history of cardiovascular disease at enrollment who had carotid artery ultrasonographic measurements recorded at a resurvey from September 2013 to June 2014 were included. Data analysis was performed from July 1, 2016, to April 10, 2019.

EXPOSURES

Major cardiovascular risk factors (ie, blood pressure [BP], blood lipid levels, smoking, and diabetes).

MAIN OUTCOMES AND MEASURES

Carotid ultrasonographic measures of plaque burden (derived from number and maximum size of carotid artery plaques at resurvey) and first ischemic stroke during follow-up (n = 952), with subtyping (data release, August 2018) as lacunar (n = 263), probable large artery (n = 193), probable cardioembolic (n = 66), or unconfirmed (n = 430). Associations between cardiovascular risk factors, carotid plaque burden, and ischemic stroke subtypes were adjusted for age, sex, and geographic area.

RESULTS

The 23 973 participants in the study had a mean (SD) age of 50.6 (10.0) years, and 14 833 (61.9%) were women. Systolic BP had a stronger association (odds ratio [OR] per SD, 1.51; 95% CI, 1.42-1.61) than plaque burden (OR per SD, 1.34; 95% CI, 1.26-1.44) with ischemic stroke, and the associations of systolic BP with each subtype of ischemic stroke were modestly attenuated by adjustment for plaque burden. After adjustment for BP, plaque burden had a stronger association with probable large artery stroke (OR, 1.43; 95% CI, 1.24-1.63) than with lacunar stroke (OR, 1.25; 95% CI, 1.10-1.43) but was not associated with probable cardioembolic stroke (OR, 1.06; 95% CI, 0.83-1.36).

CONCLUSIONS AND RELEVANCE

Although BP was an important risk factor for all ischemic stroke subtypes, carotid atherosclerosis was an important risk factor only for large artery and lacunar strokes, suggesting that drug treatments targeting atherosclerosis may reduce the risk of stroke subtypes to different extents.

Exposure to Cigarette Smoke and the Carotid Arteries Calcification Index in Patients with Essential Hypertension

The arteries calcification index is a quantitative, mathematically estimated parameter characterizing the total amount of calcium within atherosclerotic plaques in the walls of arteries. The objective is to determine a relationship between exposure to cigarette smoke and the carotid arteries calcification index in patients with essential hypertension. The tested group included 66 patients with essential hypertension: 19 active smokers (subgroup A), 20 non-smokers, environmentally exposed to cigarette smoke (subgroup B) and 27 persons without exposure to cigarette smoke (subgroup C). The tested group was subjected to computed tomography angiography of carotid arteries. Evaluation of the carotid arteries calcification indexes was conducted. The average value of the total calcification index of the carotid arteries (CAci) amounted to 368.28 ± 384.21. In subgroup A and B in relation to subgroup C, CAci was significantly higher. In summary, active and passive smoking in patients with essential hypertension may be associated with a higher calcification index of carotid arteries.

Partial Mediation by Cadmium Exposure of the Association Between Tobacco Smoking and Atherosclerotic Plaques in the Carotid Artery

Exposure to cadmium confers increased cardiovascular risk. Tobacco smoke contains cadmium, which, hypothetically, may mediate parts of the tobacco-associated risk of developing atherosclerotic plaques. Baseline data from the Swedish Malmö Diet and Cancer cohort (1991-1996) were used to test this hypothesis. Mediation analysis was used to examine associations between smoking and blood cadmium levels and the prevalence of ultrasound-assessed carotid atherosclerotic plaques. The total association with smoking status (never smokers, 2 categories of former smokers, and current smokers) was split into direct and indirect association, and the proportion mediated was estimated. The adjusted estimated plaque prevalence was approximately 27% among never smokers. We identified both a direct and an indirect pathway between smoking and carotid plaques; the indirect association, through cadmium, was observed among current smokers and former smokers who had quit smoking less than 15 years before. For current smokers, the prevalence ratio for plaque was 1.5, with 60%-65% of the association with smoking being mediated through cadmium. Recent former smokers had a prevalence ratio of 1.3, and 40%-45% was mediated through cadmium. Long-time former smokers had a prevalence ratio of 1.2, but none of the association was mediated through cadmium. In conclusion, about two-thirds of the proatherosclerotic association with smoking was mediated by cadmium.

Mortality reduction from quitting smoking in Hong Kong: population-wide proportional mortality study

BACKGROUND

The effects of smoking cessation might be different in different populations. Proportional mortality studies of all deaths, relating the certified cause to retrospectively determined smoking habits, have helped assess the hazards of smoking in Hong Kong, and further analyses can help assess the effects of prolonged cessation (although not of recent cessation, as life-threatening disease can itself cause cessation, particularly in old age).

METHODS

The LIMOR study sought the certified causes of all deaths in 1998, and interviewed 81% of families at death registries to determine the decedent's smoking history. Cases were deaths from pre-defined diseases of interest (N = 15 356); controls were deaths from pre-defined non-smoking-related diseases (N = 5023). Case vs control odds ratios for ex-smokers vs smokers were calculated by age-, sex- and education-standardized logistic regression. These are described as mortality rate ratios (RRs), with a group-specific confidence interval (CI).

RESULTS

For the aggregate of all deaths from any of the diseases of interest at ages 35-69 years, the RRs for current smoking, quitting 0-4, 5-9 or 10+ years ago and never-smoking were, respectively, RR = 1 (95% CI 0.86-1.17), 0.91 (0.73-1.14), 0.71 (0.49-1.02), 0.66 (0.50-0.87) and 0.43 (0.37-0.48). Younger age of quitting (25-44 or 45-64) appeared to be associated with greater protection: RR = 0.58 (0.38-0.88) and 0.71 (0.54-0.93), respectively. These patterns were less clear at older ages, particularly for death from emphysema.

CONCLUSIONS

Longer durations of smoking cessation are associated with progressively lower mortality rates from the diseases of interest. For sustainable monitoring of tobacco-attributed mortality, approximate years since last smoked should be recorded during death registration.

Exposure to Cigarette Smoke and the Morphology of Atherosclerotic Plaques in the Extracranial Arteries Assessed by Computed Tomography Angiography in Patients with Essential Hypertension

The aim of the study was to determine the relationship between exposure to cigarette smoke and the morphology of atherosclerotic plaques in the extracranial arteries assessed by computed tomography angiography in patients with hypertension. The study included 61 hypertensive patients: 17 active smokers (group A), 18 non-smokers, declaring environmental exposure to tobacco smoke (group B), and 26 non-smokers, not declaring exposure to cigarette smoke (group C). The number of segments with plaques was significantly higher in group A compared to groups B and C. The number of segments with non-calcified and mixed plaques was significantly higher in group A and group B than in group C. A positive correlation between cigarette-years and the number of segments with atherosclerotic plaques was noted. In summary, both active smoking and environmental exposure to tobacco smoke appear to increase the number of segments of the extracranial arteries with non-calcified and mixed atherosclerotic plaques.

Smoking and serum vitamin D in older Chinese people: cross-sectional analysis based on the Guangzhou Biobank Cohort Study

OBJECTIVE

Studies on serum vitamin D in smokers showed conflicting results. We examined the association of smoking status with serum vitamin D in older Chinese men, taking advantage of a community-based sample with natural exposure to vitamin D.

DESIGN

Cross-sectional study based on the Guangzhou Biobank Cohort Study (GBCS).

SETTING

Community-based sample from the Guangzhou Biobank Cohort Study.

PARTICIPANTS

612 male participants aged 50+years recruited from 2009 to 2011.

RESULTS

The mean (SD) of vitamin D concentration was 58.3 (17.2), 57.0 (15.0) and 54.7 (15.4) nmol/L for never, former and current smokers, respectively. Adjusted for multiple confounders, vitamin D decreased from never to former, then to current smokers (P for trend 0.02). Compared to never smokers, current smokers had lower serum concentrations of vitamin D, and the concentrations decreased with the increasing number of cigarettes per day (-3.11 (95% CI -9.05 to 2.82), -3.29 (-8.3 to 1.72) and -4.61 (-8.89 to -0.33) for 1-9, 10-19 and 20+cigarettes per day, respectively; p for trend 0.01), duration of smoking (-1.39 (-6.09 to 3.30) and -5.39 (-9.42 to -1.35) for 1-39 and 40+years, respectively; p for trend 0.008) as well as pack-years (-2.89 (-6.78 to 1.01) and -5.58 (-10.48 to -0.67) for 1-39 and 40+pack-years, respectively; p for trend 0.009). Longer duration of quitting smoking was associated with higher vitamin D than was current smoking (P for trend 0.04).

CONCLUSIONS

Current smokers had lower vitamin D than never smokers, and the association showed a dose-response pattern.

The protective effect of astragaloside IV against benzo[a]pyrene induced endothelial progenitor cell dysfunction

AIMS

Benzo[a]pyrene (BaP), a prominent component of tobacco, has been revealed to induce damage to endothelial progenitor cells (EPCs). Astragaloside IV (AS-IV) is widely used for the treatment of cardiovascular diseases in China. In this study, we evaluated the effects of AS-IV on the function of human EPCs after BaP exposure and explored the underlying mechanism.

MATERIALS AND METHODS

Human umbilical cord blood mononuclear cells were isolated using density gradient centrifugation. Cells of the 4th passage were randomly divided into 6 groups. EPCs of experimental groups were pre-treated with different concentrations (2, 10 and 50 μg/mL) of AS-IV for 2h before exposure to BaP (20 μM) for 24h. The proliferation, migration, and adhesion of the treated EPCs were evaluated using a cell counting kit-8, Transwell assay and adhesion assay respectively. Interleukin-1β, tumor necrosis factor-α, malondialdehyde and SOD contents in the supernatant were evaluated. The expression of RAGE protein was measured by Western blotting.

KEY FINDINGS

The results demonstrated that AS-IV pre-treatment significantly improved BaP-induced dysfunction of EPCs in terms of proliferation, migration and adhesion. Furthermore, AS-IV reduced the production of reactive oxygen species, malondialdehyde, interleukin-1β and tumor necrosis factor-α of the BaP-treated EPCs. Finally AS-IV pre-treated EPCs showed an increased SOD activity and decreased RAGE protein expression.

SIGNIFICANCE

AS-IV is able to prevent BaP-mediated EPC dysfunction by at least inhibiting oxidative stress through the RAGE pathway.

Metabolic syndrome showed significant relationship with carotid atherosclerosis

Metabolic syndrome (MetS) is associated with an increased risk of cardiovascular disease. We assessed the associations between MetS and the indicators of carotid atherosclerosis as assessed by ultrasonography taking into consideration of confounders in the general population. A total of 1281 subjects (856 males, 425 females) were included in the present study. The total plaque score and maximum intima-media thickness (IMT) of the carotid arteries were measured as indicators of atherosclerosis. Cardiovascular risk factors were several metabolic components, serum uric acid, serum C-reactive protein (CRP), and lifestyle factors. MetS was defined according to the criteria of the National Cholesterol Education Program. The prevalences of an elevated total plaque score (≥5) and elevated IMT (>1 mm) of the carotid arteries were significantly higher in subjects with MetS as compared to subjects without MetS. Furthermore, a trend was observed towards higher prevalences of these indicators of atherosclerosis as the number of components of MetS increased. Logistic regression analysis revealed a significant association between elevated plaque score and MetS even after adjustments for age, serum uric acid, serum CRP and lifestyle factors in the males. Among the indicators of atherosclerosis assessed by carotid ultrasonography, a significant independent association was observed between the total plaque score and MetS in males in the general population.

Prior preterm birth and maternal subclinical cardiovascular disease 4 to 12 years after pregnancy

BACKGROUND

We considered that women with prior preterm birth (PTB) would have evidence of subclinical atherosclerosis, endothelial dysfunction, and arterial stiffness.

METHODS

Four to 12 years after pregnancy, blood pressure and fasting lipids were analyzed, and women underwent evaluation, following standardized protocols, of carotid intima-media thickness (IMT), brachial flow-mediated dilation (FMD), and pulse wave velocity (PWV). Women with prior preterm (<37 weeks, n=181) or term births (>= 37 weeks, n=306) were compared. Those with preeclampsia or term small-for-gestational-age (SGA) births were excluded.

RESULTS

Women with a prior preterm vs. term birth had higher blood pressure, on average, and a more atherogenic lipid profile. They also had marginally higher IMT (0.579 standard error [SE] 0.005-vs. 0.567 [0.004] mm, p=0.06), adjusted for body size, demographics, and smoking. IMT differences were greater among those with non-preeclamptic-indicated PTB (0.034 mm, p=0.05) and PTB<34 weeks (0.024 mm, p=0.04) compared to those with term births. These differences appeared to be explained in part by the atherogenic lipid elevations in women with preterm birth. Women with prior PTB<34 weeks tended to have lower FMD, but results were not statistically significant. PWV did not differ according to PTB.

CONCLUSIONS

In the decade following pregnancy, women with non-preeclamptic-indicated PTB or PTB delivered before 34 weeks had higher blood pressure, atherogenic lipids, and IMT compared to women with term births. There may be subgroups of women with a prior PTB with excess cardiovascular risk that is detectable before overt clinical disease.

Afericoes e exames clinicos realizados nos participantes do ELSA-Brasil

Este artigo descreve os exames clínicos realizados no Estudo Longitudinal de Saúde do Adulto (ELSA-Brasil). Alguns deles (antropometria, pressão arterial e índice tornozelo-braquial) já têm uso clínico consolidado. Outros, como a velocidade de onda de pulso, variabilidade da frequência cardíaca e medida da espessura médio-intimal de carótidas, carecem de valor de referência na população brasileira não doente e podem constituir preditores importantes de desfechos cardiovasculares. A medida da pressão arterial após manobra postural foi incluída no ELSA-Brasil porque foi pouco testada em estudos epidemiológicos. O ELSA-Brasil inovou na realização do índice tornozelo-braquial, ao usar um aparelho automático em substituição à coluna de mercúrio na medida da pressão arterial, e também na medida do diâmetro ântero-posterior do lobo direito do fígado pela ultrassonografia, proposta para avaliação quantitativa da doença hepática gordurosa não-alcoólica. Os participantes são indivíduos mais jovens (a partir dos 35 anos) do que em outras coortes focadas no estudo da aterosclerose subclínica. A inclusão de indivíduos mais jovens e a diversidade dos exames realizados tornam o ELSA-Brasil um estudo relevante no contexto da epidemiologia brasileira e internacional.

Joint associations of 61 genetic variants in the nicotinic acetylcholine receptor genes with subclinical atherosclerosis in American Indians: a gene-family analysis

BACKGROUND

Atherosclerosis is the underlying cause of cardiovascular disease, the leading cause of morbidity and mortality in all American populations, including American Indians. Genetic factors play an important role in the pathogenesis of atherosclerosis. Although a single-nucleotide polymorphism (SNP) may explain only a small portion of variability in disease, the joint effect of multiple variants in a pathway on disease susceptibility could be large.

METHODS AND RESULTS

Using a gene-family analysis, we investigated the joint associations of 61 tag SNPs in 7 nicotinic acetylcholine receptor genes with subclinical atherosclerosis, as measured by carotid intima-media thickness and plaque score, in 3665 American Indians from 94 families recruited by the Strong Heart Family Study (SHFS). Although multiple SNPs showed marginal association with intima-media thickness and plaque score individually, only a few survived adjustments for multiple testing. However, simultaneously modeling of the joint effect of all 61 SNPs in 7 nicotinic acetylcholine receptor genes revealed significant association of the nicotinic acetylcholine receptor gene family with both intima-media thickness and plaque score independent of known coronary risk factors.

CONCLUSIONS

Genetic variants in the nicotinic acetylcholine receptor gene family jointly contribute to subclinical atherosclerosis in American Indians who participated in the SHFS. These variants may influence the susceptibility of atherosclerosis through pathways other than cigarette smoking per se.

Cadmium exposure is accompanied by increased prevalence and future growth of atherosclerotic plaques in 64-year-old women

OBJECTIVES

There is currently widespread exposure to the toxic metal cadmium through the diet as well as through smoking, and it has been suggested that cadmium exposure may increase the risk of cardiovascular disease. Here we examined whether cadmium exposure is associated with prevalence and growth of atherosclerotic plaques in the carotid arteries.

DESIGN AND SUBJECTS

The analyses were performed in a screening-based cohort of 64-year-old Caucasian women with stratified, random selection to groups with normal glucose tolerance, impaired glucose tolerance and diabetes (n = 599). We measured cadmium concentrations in blood and urine at baseline. In addition, we performed ultrasound examination to determine the prevalence and area of atherosclerotic plaques in the carotid arteries and assessed smoking history and other cardiovascular risk factors at baseline and at a follow-up examination after a mean of 5.4 years.

RESULTS

At baseline, blood cadmium levels were associated with increased risk of plaque and a large plaque area after adjustment for confounders. In women who had never smoked, blood cadmium levels correlated positively with plaque area at baseline. The occurrence of large plaques and the change in plaque area at follow-up were associated with blood and creatinine-corrected urinary cadmium concentrations at baseline after adjustment for confounders. Blood and urine cadmium levels added information to established cardiovascular risk factors in predicting progress of atherosclerosis.

CONCLUSIONS

We have shown that cadmium levels in blood and urine are independent factors associated with the development of atherosclerotic plaques at baseline as well as prospectively. This novel observation emphasizes the need to consider cadmium as a pro-atherogenic pollutant.

Effects of cigarette smoking, metabolic syndrome and dehydroepiandrosterone deficiency on intima-media thickness and endothelial function in hypertensive postmenopausal women

Background

Cigarette smoking is a major risk factor of atherosclerosis. The aim of this study was to assess the relationship between smoking and arterial hypertension as well as endothelial dysfunction in postmenopausal women without clinically manifested symptoms of atherosclerosis.

Material/Methods

The study groups consisted of 35 current smokers and 45 nonsmokers. The thickness of intima-media complex (IMT), a marker of atherosclerosis, was measured in carotid arteries. Plasma concentrations of fasting glucose, insulin, lipoproteins, inflammatory markers (tumor necrosis factor-alpha, intercellular adhesion molecule-1), matrix metalloproteinases (metalloproteinase-9, tissue inhibitor of metalloproteinase-1), insulin, and dehydroepiandrosterone sulfate (DHEA-S) were measured.

Results

Smokers compared with nonsmokers showed lower fasting glucose levels in blood (87.0±10.9 and 93.2±13.6 mg/dl, p<0.05), higher mean systolic (131.1±15.9 vs. 123.0±10.9 mm Hg, p<0.05) and diastolic (81.7±11.4 vs. 75.2±9.2 mm Hg, p<0.05) blood pressure during daytime, and higher average heart rate during the daytime (78.2±9.3/min vs. 71.5±9.5/min, p<0.01) and at night (67.2±10.6/min vs. 61.7±7.7/min, p<0.05), respectively. The IMT in the right carotid artery was significantly higher in smokers than in nonsmokers (0.96±0.16 mm vs. 0.82±0.21, p<0.05) and was positively correlated with smoking intensity (R=0.36) and habit duration (R=0.35). The comparison of inflammatory markers, metalloproteinases, and DHEA-S concentrations in plasma did not reveal significant differences between the 2 groups. A significant negative correlation between DHEA-S concentration in plasma and IMT in right carotid artery was found in smokers.

Conclusions

Smoking in hypertensive postmenopausal women is associated with lower fasting blood glucose and BMI values, but higher arterial pressure and heart rate, and increases in IMT in right carotid artery.

Aging, components of metabolic syndrome and serum C-reactive protein showed significant relationship with carotid atherosclerosis

OBJECTIVE

metabolic syndrome (MetS) is known to be associated with an increased risk for cerebro- as well as cardio-vascular disease. Prediction of carotid atherosclerosis by components of MetS, serum C-reactive protein, aging and related factors was conducted for Japanese inhabitants.

METHODS

A total of 887 subjects (761 males, 126 females) were included in the present study. Early atherosclerosis was assessed by measurement of the intima-media thickness of the common carotid arteries.

RESULTS

The carotid arterial intima-media thickness on both the right and left sides significantly increased as the number of components of MetS increased. The maximum intima-media thickness values in the right (left) carotid arteries in the male and female subjects who fulfilled the criteria for MetS were 0.65 ± 0.18 (0.66 ± 0.17) mm and 0.58 ± 0.12 (0.59 ± 0.11) mm, respectively. After adjustment for several factors, the intima-media thickness related significantly with aging, some components of MetS and serum C-reactive protein by multiple regression analysis. β-coefficient of age was largest, presenting 0.457 in right side and 0.479 in left side.

CONCLUSIONS

Aging, metabolic components and serum C-reactive protein are independent predictors of intima-media thickness in subjects.

The utility of collaborative biobanks for cardiovascular research

Differences between animal and human atherosclerosis have led to the requirement for clinical data, imaging information and biological material from large numbers of patients and healthy persons. Where such "biobanks" exist, they have been fruitful sources for genomewide association, diagnostic accuracy, ethnicity, and risk stratification cohort studies. In addition once established, they attract funding for future projects. Biobanks require a network of medical contributors, secure storage facilities, bioinformatics expertise, database managers, and ethical working practices to function optimally. There is the opportunity for collaboration between individual biobanks to further amplify the advantages afforded.