Relationship between amount of cigarette smoking and coronary atherosclerosis on coronary CTA in asymptomatic individuals

Dose-Dependent association of cumulative tobacco consumption with the presence of carotid atherosclerosis in individuals with type 1 diabetes

AIMS

Evaluate the association between cumulative tobacco consumption (CTC; packs-year) and atherosclerosis in type 1 diabetes (T1D), and study whether the inclusion of CTC in the Steno T1 Risk Engine (ST1RE) equation improves the identification of plaques.

METHODS

Cross-sectional study in T1D patients without cardiovascular disease (CVD), with ≥ 1 of the following: ≥40 years-old, diabetic kidney disease, and/or T1D duration ≥ 10 years + cardiovascular risk factors.Preclinical atherosclerosis was evaluated by carotid ultrasonography.

RESULTS

N = 584 patients were included (46.1 % women, age 48.7 ± 10.5 years, T1D duration 27.3 ± 10.8 years, 26.2 % active smokers). The overall plaque prevalence was 40.9 %. In models adjusted for age, sex, lipids, blood pressure, kidney function, statin use, microvascular complications and HbA1c, CTC was dose-dependently associated with the number of plaques (none, 1-2, ≥3) overall and in both active and former smokers (p < 0.001). This association remained after adjusting for ST1RE (OR 1.11 [1.02-1.19]). Although the inclusion of CTC in the ST1RE did not improve plaque identification overall (p = 0.180), it did so when analyzing active smokers separately (AUC 0.738 vs. 0.768; p < 0.01).

CONCLUSIONS

In T1D patients, CTC is dose-dependently associated with atherosclerosis. Further prospective studies are needed to determine if CTC could identify T1D individuals more prone to accelerated atherosclerosis.

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.

Smoking and the Pathophysiology of Peripheral Artery Disease

Smoking is one of the most important preventable factors causing peripheral artery disease (PAD). The purpose of this review is to comprehensively analyze and summarize the pathogenesis and clinical characteristics of smoking in PAD based on existing clinical, in vivo, and in vitro studies. Extensive searches and literature reviews have shown that a large amount of data exists on the pathological process underlying the effects of cigarette smoke and its components on PAD through various mechanisms. Cigarette smoke extracts (CSE) induce endothelial cell dysfunction, smooth muscle cell remodeling and macrophage phenotypic transformation through multiple molecular mechanisms. These pathological changes are the molecular basis for the occurrence and development of peripheral vascular diseases. With few discussions on the topic, we will summarize recent insights into the effect of smoking on regulating PAD through multiple pathways and its possible pathogenic mechanism.

Use of Coronary Computed Tomography Angiography to Screen Hospital Employees with Cardiovascular Risk Factors

The objective of this study was to determine how coronary computed tomography angiography (CCTA) can be employed to detect coronary artery disease in hospital employees, enabling early treatment and minimizing damage. All employees of our hospital were assessed using the Framingham Risk Score. Those with a 10-year risk of myocardial infarction or death of >10% were offered CCTA; the Coronary Artery Disease Reporting and Data System (CAD-RADS) score was the outcome. A total of 3923 hospital employees were included, and the number who had received CCTA was 309. Among these 309, 31 (10.0%) had a CAD-RADS score of 3-5, with 10 of the 31 (32.3%) requiring further cardiac catheterization; 161 (52.1%) had a score of 1-2; and 117 (37.9%) had a score of 0. In the multivariate logistic regression, only age of ≥ 55 years (p < 0.05), hypertension (p < 0.05), and hyperlipidemia (p < 0.05) were discovered to be significant risk factors for a CAD-RADS score of 3-5. Thus, regular and adequate control of chronic diseases is critical for patients, and more studies are required to be confirmed if there are more significant risk factors.

Hyperuricemia and Its Associated Factors Among Adult Staff Members of the Ethiopian Public Health Institute, Ethiopia

Background

Hyperuricemia is related not only to an increased risk of gouty arthritis but also to an increased risk of cardiovascular diseases, resistant hypertension, insulin resistance and progression of type 2 diabetes mellitus. However, to the best of our knowledge, the prevalence of hyperuricemia and its associated factors have rarely been assessed in Ethiopian populations. Therefore, this study aimed to determine the prevalence of hyperuricemia and its associated factors among adult staff members of the Ethiopian Public Health Institute.

Methods

An institution-based cross-sectional study was conducted from July 1 to October 28, 2018. A total of 402 study participants were selected using a simple random sampling technique. An interviewer-administered questionnaire was used to collect the data. A blood sample of approximately 5 mL was collected from each study participant after overnight fasting through standardized methods for biochemical tests, and analyses were carried out with an automated COBAS 6000 analyzer. Data analysis was performed by SPSS version 20 software. The factors associated with the outcome variable were identified by bivariable and multivariable logistic regression analyses, and a p value <0.05 was used to declare statistical significance.

Results

The mean age of the study participants was 37.13±10.5 (mean ± SD), and 51.5% of the participants were male. The overall prevalence of hyperuricemia (>5.7 mg/dL for females and >7 mg/dL for males) was found to be 31.0%. The multivariable logistic analysis revealed that age (AOR=1.59, 95% CI 1.01–2.78), sex (AOR=1.66, 95% CI 1.02–2.70), cigarette smoking (AOR=2.05, 95% CI 1.01–4.19) and serum low-density lipoprotein (LDL) (AOR=1.70, 95% CI 1.01–2.87) were significantly associated with hyperuricemia.

Conclusion

The prevalence of hyperuricemia was relatively high compared to similar studies. Early screening for hyperuricemia in the general population, especially in those who are smokers, of older age and with high serum LDL levels, is vital to control its adverse effects at an early stage.

Association between latent tuberculosis and ischemic heart disease: a hospital-based cross-sectional study from Saudi Arabia

Introduction

atherosclerosis could be a sequela of long-term activation of cell-mediated immunity as the case of latent tuberculosis infection. Atherosclerosis is the main pathological event in ischemic heart disease. The present study aimed to assess the prevalence of Latent tuberculosis infection (LTBI) among patients with ischemic heart disease (IHD) and to detect the association between both diseases.

Methods

this cross-sectional study included 98 patients with a history of previously diagnosed ischemic heart disease who did a multi-detector computed tomography coronary angiogram (MDCTCA). Detailed clinical examination and investigations as chest X-ray and sputum examination were done for those with positive QuantiFERON-TB Gold test (QFT) to exclude active tuberculosis (TB). Participants having positive QFT results but with no evidence of active TB were considered as LTBI positive.

Results

the prevalence of LTBI in patients with IHD was 19.3% as only nineteen of the ninety-eight patients were diagnosed with latent tuberculosis infection using the QuantiFERON serum test. Eighty-four percent (84.2%) of patients with LTBI had coronary artery atherosclerosis (CAA) compared to only 55.6% in patients without LTBI with a statistically significant difference. In multivariable analysis, Diabetes Mellitus (DM) (AOR 0.179, 95% C.I.: 0.03-0.967), and LTBI (AOR 1.024, 95% C.I.: 1.002-1.736) were significantly associated with coronary artery atherosclerosis (p=0.0001, and p= 0.003 respectively).

Conclusion

the prevalence of latent tuberculosis infection among patients with ischemic heart diseases is high. Among different factors that are already well known to precipitate ischemic heart disease, latent tuberculosis should be considered.

Associations between smoking habits and major adverse cardiovascular events in patients who underwent coronary computed tomography angiography as screening for coronary artery disease

We analyzed whether smoking was associated with major adverse cardiovascular events (MACE) and the progression of coronary atherosclerosis as assessed by coronary computed tomography angiography (CCTA) as screening for coronary artery disease (CAD). We enrolled 443 patients who had all undergone CCTA and either were clinically suspected of having CAD or had at least one cardiovascular risk factor. We divided the patients into smoking (past and current smoker) and non-smoking groups and into males and females, and evaluated the presence of CAD, severity of coronary atherosclerosis and MACE (cardiovascular death, ischemic stroke, acute myocardial infarction and coronary revascularization) with a follow-up of up to 5 years. %CAD and the severity of coronary atherosclerosis in the smoking group were significantly higher than those in the non-smoking group. %MACE in males and smokers were significantly higher than those in females and non-smokers, respectively. Interestingly, Kaplan-Meier curves also showed that female non-smokers enjoyed significantly greater freedom from MACE than female smokers (p = 0.007), whereas there was no significant difference in freedom from MACE between male non-smokers and male smokers (p = 0.984). Although there were no significant predictors of MACE in all patients according to a multiple logistic regression analysis, smoking was useful for predicting MACE in females, but not males. In conclusion, smoking was significantly associated with MACE in females, but not males, who underwent CCTA as screening for CAD.

Associations of cigarette smoking and burden of thoracic aortic calcification in asymptomatic individuals: A dose-response relationship

Smoking is known as a powerful predictor of pathological coronary atherosclerosis. Thoracic aortic calcification (TAC), an alternative marker for pathological atherosclerosis, has also been shown to be associated unfavorable cardiovascular outcomes. We aimed to investigate the dose-response relationship between cigarette use and calcification burden in subjects free from clinical symptoms. Among 3109 patients enrolled in this analysis, we categorized study participants according to smoking exposure pattern as: non-smokers, ex-smokers and current smokers. Smoking dose (cigarette/day), duration (years) and pack-years were semi-quantified as smoking dose exposure variables. Thoracic aortic calcification burden (including TAC score, plaque volume and plaque density) were determined and related to smoking dose and pattern information. TAC burdens (including TAC score, plaque volume and density) were highest in current smoker compared to non-smoker group, with ex-smoker showing TAC burdens in-between (all ANOVA p<0.05). Linear regression models consistently demonstrated that TAC burdens as continuous variables were independently higher in a dose-dependent manner with smoking exposure, particularly in high-dose (> 10 cigarettes/day) and the long-duration (> 3 years) smokers, even after adjusting for baseline demographic differences (all p<0.05). By logistic regression, subjects who never smoke consistently demonstrated reduced risk of TAC existence (adjusted OR: 0.65 [95% CI: 0.48–0.86], P = 0.003) in contrary to those current smokers (adjusted OR: 1.47 [95% CI: 1.10–1.89], P = 0.009). A dose-response relationship between active cigarette use and TAC burden was observed, with those who never exposed to smoking or quitted demonstrating partial protective effects. Our data provided imaging-based evidence about the potential deleterious biological hazards of long-term and high-dose cigarette consumption.

Association of smoking with coronary artery disease in Nepalese populations: a case control study

There are well-known traditional risk factors for coronary artery disease (CAD). Among them, smoking is one of the most prominent and modifiable risk factors. This study aims to determine the magnitude of smoking as a risk factor for CAD in the Nepalese population. A hospital-based age- and sex-matched case-control study was carried out with a total of 612 respondents. Bivariate analysis showed that the risk of developing CAD in ex-smokers and current smokers was higher (odds ratio (OR): 1.81 (confidence interval (CI): 1.21-2.7) and OR: 5.2 (CI: 3.4-7.97)), with p-values less than 0.004 and <0.00001, respectively, compared to the risk in never smokers. From stratified socio-demographic, cardio-metabolic, behavioural and psychosocial risk factor analysis, smoking was found to be associated with CAD in almost all subgroups. In the subsequent multivariate analysis, adjustment for socio-demographic, cardio-metabolic and psychosocial risk factors showed a steady increase in risk. However, further adjustment for behavioural risk factors (alcohol use and physical activity) showed that the risk was attenuated by 59% in current smokers. After adjusting for the covariates, current smokers and ex-smokers had an increased risk of CAD (OR: 6.64, 95% CI: 3.64-12.12, p < 0.00001; OR: 1.89, 95% CI: 1.08-3.31, p < 0.012, respectively) compared with non-smokers. In conclusion, smoking was found to increase the risk of CAD in the Nepalese population.

Association between smoking and serum uric acid in Korean population: Data from the seventh Korea national health and nutrition examination survey 2016

The aim of this study was to identify any association between serum uric acid and smoking status using data from the Seventh Korea National Health and Nutrition Examination Survey (KNHANES VII-1) 2016 of the Korean population.This study used a cross-sectional design and analyzed 5609 subjects aged ≥ 19 years among 8150 participants enrolled in the KNHANES VII-1 2016. Smoking status was classified into current smokers, never smokers, and ex-smokers. Hyperuricemia was defined as > 7.0 mg/dL for men and > 6.0 mg/dL of serum uric acid for women. Association between smoking and serum uric acid/hyperuricemia was assessed by Pearson's or Spearman's correlation analyses and multivariate logistic regression analysis showing odds ratio (OR) and 95% confidence interval (CI).A significant difference in serum uric acid according to smoking status was identified in female (P < .001) but not in male subjects (P = .069). In female subjects, current smokers and ex-smokers showed higher serum uric acid than never smokers (P < 0.001 of both). Serum uric acid was associated with smoking status in female but not male subjects (r = 0.057, P = .001 and r = 0.025, P = .220, respectively). There was significant difference of smoking status between female subjects with and without hyperuricemia (P < .001). Current smokers had 2.7 times higher likely to have hyperuricemia in female, compared to never smokers (OR 2.674, 95% CI 1.578 - 4.531, P < .001).This study revealed that smoking was closely associated with serum uric acid in female but not in male subjects in Korean population.

Interaction between tissue factor pathway inhibitor-2 gene polymorphisms and environmental factors associated with coronary atherosclerosis in a Chinese Han

To investigate the association of single nucleotide polymorphisms (SNPs) within tissue factor pathway inhibitor-2 (TFPI-2) gene polymorphisms and additional gene-environment interaction with coronary atherosclerosis risk. Generalized multifactor dimensionality reduction (GMDR) was used to screen the best interaction combination among 4 SNPs, smoking and alcohol drinking. Logistic regression was performed to investigate association between 4 SNPs within TFPI-2 gene and coronary atherosclerosis risk. Coronary atherosclerosis risk was significantly higher in carriers with the A allele of rs34489123 within TFPI-2 gene than those with GG genotype (GA+AA versus GG), adjusted OR (95% CI) = 1.70 (1.20-2.31), and was also higher in carriers with the G allele of rs4264 within TFPI-2 gene than those with AA genotype (AG+GG versus AA), adjusted OR (95% CI) = 1.62 (1.21-2.11). GMDR model shown the best models for gene-environment interaction were rs34489123 and smoking after adjusting the covariates, which scored 10 out of 10 for cross-validation consistency and 0.0010 for the sign test. Heavy LD was found for SNPs rs34489123 and rs59805398 (D' value was more than 0.8). Compared to control individuals, the AG haplotypes appeared to be significantly associated with increased coronary atherosclerosis risk, OR (95% CI) = 1.73 (1.22-2.32). We found that the A allele of rs34489123 and the G allele of rs4264 within TFPI-2 gene, interaction between rs34489123 and smoking and AG haplotypes were all associated with increased coronary atherosclerosis risk.

Downregulated Serum 14, 15-Epoxyeicosatrienoic Acid Is Associated With Abdominal Aortic Calcification in Patients With Primary Aldosteronism

Patients with primary aldosteronism (PA) have increased risk of target-organ damage, among which vascular calcification is an important indicator of cardiovascular mortality. 14, 15-Epoxyeicosatrienoic acid (14, 15-EET) has been shown to have beneficial effects in vascular remodeling. However, whether 14, 15-EET associates with vascular calcification in PA is unknown. Thus, we aimed to investigate the association between 14, 15-EET and abdominal aortic calcification (AAC) in patients with PA. Sixty-nine patients with PA and 69 controls with essential hypertension, matched for age, sex, and blood pressure, were studied. 14, 15-Dihydroxyeicosatrienoic acid (14, 15-DHET), the inactive metabolite from 14, 15-EET, was estimated to reflect serum 14, 15-EET levels. AAC was assessed by computed tomographic scanning. Compared with matched controls, the AAC prevalence was almost 1-fold higher in patients with PA (27 [39.1%] versus 14 [20.3%]; P=0.023), accompanied by significantly higher serum 14, 15-DHET levels (7.18±4.98 versus 3.50±2.07 ng/mL; P<0.001). Plasma aldosterone concentration was positively associated with 14, 15-DHET (β=0.444; P<0.001). Multivariable logistic analysis revealed that lower 14, 15-DHET was an independent risk factor for AAC in PA (odds ratio, 1.371; 95% confidence interval, 1.145-1.640; P<0.001), especially in young patients with mild hypertension and normal body mass index. In conclusion, PA patients exibited more severe AAC, accompanied by higher serum 14, 15-DHET levels. On the contrary, decreased 14, 15-EET was significantly associated with AAC prevalence in PA patients, especially in those at low cardiovascular risk.

An association of smoking with serum urate and gout: A health paradox

BACKGROUND

The potential effect of cigarette smoking on levels of serum urate and risk of gout has been considered by a large number of studies, either as the primary variable of interest or as a covariate.

METHODS

Here we systematically review the published evidence relating to the relationship of smoking with serum urate, hyperuricaemia, and gout.

RESULTS

Many studies have reported that smoking reduces serum urate, however, the evidence has not been conclusive with other studies pointing to the opposite or no effect. It has also been suggested that smoking reduces the risk of gout, although there is some evidence to contradict this finding.

CONCLUSION

A consensus has yet to be reached as to the effect of smoking on serum urate levels and the risk of gout.

Association of tobacco use and cessation with coronary atherosclerosis

BACKGROUND AND AIMS

The impact of tobacco use and cessation on atherogenesis remains unclear. We aimed to study the association of tobacco use and prior cessation with the presence, extent and severity of atherosclerosis on coronary computed tomographic angiography (CTA).

METHODS

We examined 1798 consecutive symptomatic patients without known coronary artery disease (CAD) referred for CTA, stratified by smoking status (never, current [within 30 days], or former [>30 days before CTA]). Plaque severity (none, <50%, ≥50% stenosis), composition (non-calcified [NCP], partially calcified [PCP], or calcified plaque [CP]), and segment involvement score (SIS) were visually graded. Multivariate analysis was performed, adjusting for CAD risk factors and cholesterol lowering medication use.

RESULTS

The median age of patients was 50 years [IQR:42-58] (61% male), with 74% never smokers, 12% current smokers, and 14% former smokers (median quit duration = 12 years [IQR:3-26]). Smoking exposure in former versus current smokers was 11 [IQR:5-25] and 10 [IQR:2-20] pack-years, respectively (p = 0.01). Compared to never smokers, current smokers demonstrated an increased odds ratio of all plaque types (adjusted OR: any NCP = 1.55 [95% CI 1.04-2.32], p = 0.03; any PCP = 1.61 [1.10-2.37], p = 0.02; any CP = 1.93 [1.32-2.81], p = 0.001), non-obstructive CAD (aOR = 1.47 [1.04, 2.07], p = 0.03), obstructive CAD (aOR = 1.81 [1.01-3.24], p = 0.047), and SIS > 4 (aOR = 1.60 [1.04-2.46], p = 0.03). Compared to current smoking, prior smoking cessation (≥12 years) was associated with a decreased odds ratio of any NCP (aOR = 0.42 [0.19-0.90], p = 0.03), CP (aOR = 0.43 [0.22-0.84], p = 0.02), and obstructive CAD (aOR = 0.40, [0.15-0.98], p = 0.048).

CONCLUSIONS

Current smoking is independently associated with the presence and extent of coronary plaque, and a higher risk of non-obstructive and obstructive CAD compared to never smoking. Prior smoking cessation correlated with improvements in CTA-identified plaque measures.

The Association of Secondhand Tobacco Smoke and CT Angiography-Verified Coronary Atherosclerosis

OBJECTIVES

The aim of this study was to assess the relationship of the extent of atherosclerosis on coronary computed tomographic angiography to the extent of secondhand tobacco smoke (SHTS) exposure in asymptomatic never smokers.

BACKGROUND

A dose-related association between SHTS and coronary artery calcium has been reported, but the total extent of atherosclerosis has not been investigated.

METHODS

A total of 268 never smokers, ages 40 to 80 years, completed a questionnaire assessing risk factors and extent of lifetime SHTS exposure, providing a total SHTS exposure score. Ordinal coronary artery calcium scores were derived from low-dose nongated computed tomographic scans, followed by computed tomographic angiography. Analyses of the prevalence, extent, and plaque characteristics of atherosclerosis were performed, and the independent contribution of SHTS, adjusted for other documented risk factors, was determined.

RESULTS

Coronary atherosclerosis was noted in 48% and was more frequent with low to moderate and high versus minimal SHTS exposure (48% and 69% vs. 25%; p < 0.0001). Adjusted odds ratios for any atherosclerosis were 2.1 (95% confidence interval: 1.0 to 4.4; p = 0.05) for low to moderate and 3.5 (95% confidence interval: 1.4 to 8.5; p = 0.01) for high exposure versus minimal SHTS exposure and were not significant for standard risk factors of diabetes (p = 0.56), hyperlipidemia (p = 0.11), hypertension (p = 0.65), and renal disease (p = 0.24). With increasing SHTS exposure, the percentage of major vessel (14%, 41%, and 45%; p = 0.0013) with any plaque or stenosis increased, as did the number with 5 or more involved segments (0%, 39%, and 61%; p = 0.0001). Also the average number of involved segments increased (0.82, 1.98, and 3.49; p < 0.0001), with calcified plaques alone (0.25, 0.77, and 1.52; p < 0.0001), with calcified and partially calcified plaques (0.28, 0.82, and 1.58; p < 0.001), but not with noncalcified plaques alone (p = 0.11).

CONCLUSIONS

The presence and extent of atherosclerosis were associated with the extent of SHTS exposure even when adjusted for other risk factors, further demonstrating the causal relationship of SHTS exposure and coronary disease.

Smoking in Relation to Coronary Atherosclerotic Plaque Burden, Volume and Composition on Intravascular Ultrasound

Background

This study aimed to evaluate the relationship between cigarette smoking and coronary atherosclerotic burden, volume and composition as determined in-vivo by grayscale and virtual histology (VH) intravascular ultrasound (IVUS).

Methods and Results

Between 2008 and 2011, (VH-)IVUS of a non-culprit coronary artery was performed in 581 patients undergoing coronary angiography. To account for differences in baseline characteristics, current smokers were matched to never smokers by age, gender and indication for catheterization, resulting in 280 patients available for further analysis. Coronary atherosclerotic plaque volume, burden, composition (fibrous, fibro-fatty, dense calcium and necrotic core) and high-risk lesions (VH-IVUS derived thin-cap fibroatheroma (TCFA), plaque burden ≥70%, minimal luminal area ≤4.0 mm²) were assessed. Cigarette smoking showed a tendency towards higher coronary plaque burden (mean±SD, 38.6±12.5% in current versus 36.4±11.0% in never smokers, p = 0.080; and odds ratio (OR) of current smoking for plaque burden above versus below the median 1.69 (1.04–2.75), p = 0.033). This effect was driven by an association in patients presenting with an acute coronary syndrome (ACS) (current smokers, plaque burden 38.3±12.8% versus never smokers, plaque burden 35.0±11.2%, p = 0.049; OR 1.88 (1.02–3.44), p = 0.042). Fibrous tissue tended to be lower in current smokers (mean±SD, 57.7±10.5% versus 60.4±12.6%, p = 0.050) and fibro-fatty tissue was higher in current smokers (median[IQR], 9.6[6.0–13.7]% versus 8.6[5.8–12.2]%, p = 0.039). However, differences in percentage necrotic core and dense calcium could not be demonstrated. Also, no differences were found with regard to high-risk lesions.

Conclusions

An association between smoking and degree of coronary atherosclerosis was present in patients undergoing coronary angiography who presented with ACS. Although smoking was associated with higher fibro-fatty percentage, no associations could be demonstrated with percentage necrotic core, nor with VH-IVUS derived TCFA lesions. Since the magnitude of the differences in both degree and composition of atherosclerosis was modest, clinical relevance of the findings may be questioned.

Association between smoking habits and severity of coronary stenosis as assessed by coronary computed tomography angiography

Smoking promotes arteriosclerosis and is one of the most important coronary risk factors. However, few studies have investigated the association between smoking habits and the severity of coronary stenosis as assessed by coronary computed tomography angiography (CTA). We enrolled 416 patients [165/251 = smoker (past and current)/non-smoker)]. They had all undergone CTA and either were clinically suspected of having coronary artery disease (CAD) or had at least one cardiovascular risk factor. We divided the patients into smoking and non-smoking groups, and evaluated the presence of CAD, the number of significantly stenosed coronary vessels (VD), and the Gensini score as assessed by CTA in the two groups. The incidence of CAD, VD, the Gensini score, and coronary calcification score in the smoking group were all significantly greater than those in the non-smoking group (CAD, p = 0.009; VD, p = 0.003; Gensini score, p = 0.007; coronary calcification score, p = 0.01). Pack-year was significantly associated with VD and the Gensini score, and was strongly associated with multi-vessel disease (2- and 3-VD) (p < 0.05), whereas the duration of cessation in past smokers was not associated with VD or the Gensini score. Pack-year, but not the duration of cessation, may be the most important factor that was associated with the severity of coronary stenosis in terms of VD and the Gensini score.

Grade-response relationship between blood pressure and severity of coronary atherosclerosis in asymptomatic adults: assessment with coronary CT angiography

Hypertension is known to be a strong risk factor for coronary atherosclerosis. We aimed to investigate the prevalence, severity, and plaque characteristics of coronary atherosclerosis according to grade of blood pressure (BP) using coronary CT angiography (CCTA) in asymptomatic adults. We enrolled 8,238 asymptomatic subjects who underwent coronary artery calcium scoring (CACS) and CCTA for health screening purposes. Subjects were classified according to JNC 7 guidelines (normal, systolic BP/diastolic BP < 120/80; pre-hypertension [PH], 120-139/80-89; hypertension stage 1 [H1], 140-159/90-99; hypertension stage 2 [H2], >160/100). Isolated systolic hypertension (ISH; systolic BP > 140, diastolic BP < 80) was additionally categorized. With CCTA, the presence of plaques, severity of stenosis, and plaque types were assessed. Using multiple logistic regression analysis, the adjusted odds ratios (AORs) for plaque, obstructive coronary artery disease (CAD) (luminal stenosis ≥50 %), non-calcified plaque (NCP), and CACS > 100 were assessed according to BP grade. After adjustment for clinical risk factors, the risk of subclinical atherosclerosis, NCP, and CACS > 100 gradually increased from PH stage (all P values for trend <0.05), while the risk of obstructive CAD increased from the H1 stage (AORs of H1 and H2: 1.70 and 2.33, respectively). In the ISH group, the AOR of subclinical atherosclerosis (1.64) was higher than in the H1 group (1.55), while the AOR of obstructive CAD (2.58) was higher than in the H2 group (2.33). Therefore, our study strongly suggests that coronary atherosclerosis in asymptomatic adults shows a grade-response relationship according to hypertension grade.

Cigarette smoking exacerbates the adverse effects of age and metabolic syndrome on subclinical atherosclerosis: the Bogalusa Heart Study

Age and metabolic syndrome are major risk factors for atherosclerosis. However, limited information is available regarding whether cigarette smoking, another major, modifiable risk factor, has synergistic effects with age and metabolic syndrome on subclinical atherosclerosis, particularly in young adults. This aspect was examined in 1,051 adults (747 whites and 304 blacks; aged 24–43 years) from the Bogalusa Heart Study. General linear models were used to examine the effects of cigarette smoking and its interactive effects with age and metabolic syndrome on carotid intima-media thickness (CIMT). After adjusting for age, race, and sex, current smokers had lower BMI (mean±SE: 27.4±0.4, 29.3±0.5, and 29.9±0.3 kg/m² in current, former, and never smokers, respectively; p<0.0001) and lower levels of fasting glucose (82.8±0.9, 89.5±2.3, and 87.1±1.1 mg/dL, respectively; p = 0.001) and insulin (10.6±0.4, 14.2±1.0, 13.6±0. 6 µU/ml, respectively; p<0.0001). Despite being lean and having favorable levels of glucose and insulin, current smokers had greater CIMT (0.850±0.012, 0.808±0.011, and 0.801±0.006 mm, respectively; p = 0.0004). Importantly, cigarette smoking showed significant interactions with age and metabolic syndrome on CIMT: Age-related change in CIMT in current smokers was significantly greater (0.013±0.002 mm/year) than in nonsmokers (former and never smokers combined) (0.008±0.001 mm/year) (p for interaction = 0.005); the difference in CIMT between those with and without metabolic syndrome was significantly greater in current smokers (0.154±0.030 mm, p<0.0001) than in nonsmokers (0.031±0.014 mm, p = 0.03) (p for interaction<0.0001). In conclusion, cigarette smoking significantly exacerbates the adverse effects of age and metabolic syndrome on subclinical atherosclerosis in young adults, which underscores the importance of prevention and cessation of cigarette smoking behavior in the young.