Smoking Status and Metabolic Syndrome in the Multi-Ethnic Study of Atherosclerosis. A cross-sectional study

Metabolic and Other Endocrine Elements with Regard to Lifestyle Choices: Focus on E-Cigarettes

Our objective was to overview recent data on metabolic/endocrine disorders with respect to e-cigarette (e-cig) use. This is a narrative review; we researched English, full-length, original articles on PubMed (between January 2020 and August 2023) by using different keywords in the area of metabolic/endocrine issues. We only included original clinical studies (n = 22) and excluded case reports and experimental studies. 3 studies (N1 = 22,385; N2 = 600,046; N3 = 5101) addressed prediabetes risk; N1 showed a 1.57-fold increased risk of dual vs. never smokers, a higher risk that was not confirmed in N2 (based on self-reported assessments). Current non-smokers (N1) who were dual smokers still have an increased odd of prediabetes (a 1.27-fold risk increase). N3 and another 2 studies addressed type 2 diabetes mellitus (DM): a lower prevalence of DM among dual users (3.3%) vs. cigarette smoking (5.9%) was identified. 6 studies investigated obesity profile (4 of them found positive correlations with e-cig use). One study (N4 = 373,781) showed that e-cig use was associated with obesity in the general population (OR = 1.6, 95%CI: 1.3-2.1, p < 0.05); another (N5 = 7505, 0.82% were e-cig-only) showed that obesity had a higher prevalence in dual smokers (51%) vs. cig-only (41.2%, p < 0.05), while another (N6 = 3055) found that female (not male) e-cig smokers had higher body mass index vs. non-smokers. Data on metabolic syndrome (MS) are provided for dual smokers (n = 2): one case-control study found that female dual smokers had higher odds of MS than non-smokers. The need for awareness with respect to potential e-cig--associated medical issues should be part of modern medicine, including daily anamnesis. Whether the metabolic/endocrine frame is part of the general picture is yet to be determined. Surveillance protocols should help clinicians to easily access the medical background of one subject, including this specific matter of e-cig with/without conventional cigarettes smoking and other habits/lifestyle elements, especially when taking into consideration metabolism anomalies.

The effect of smoking on latent hazard classes of metabolic syndrome using latent class causal analysis method in the Iranian population

BACKGROUND

The prevalence of metabolic syndrome is increasing worldwide. Clinical guidelines consider metabolic syndrome as an all or none medical condition. One proposed method for classifying metabolic syndrome is latent class analysis (LCA). One approach to causal inference in LCA is using propensity score (PS) methods. The aim of this study was to investigate the causal effect of smoking on latent hazard classes of metabolic syndrome using the method of latent class causal analysis.

METHODS

In this study, we used data from the Tehran Lipid and Glucose Cohort Study (TLGS). 4857 participants aged over 20 years with complete information on exposure (smoking) and confounders in the third phase (2005-2008) were included. Metabolic syndrome was evaluated as outcome and latent variable in LCA in the data of the fifth phase (2014-2015). The step-by-step procedure for conducting causal inference in LCA included: (1) PS estimation and evaluation of overlap, (2) calculation of inverse probability-of-treatment weighting (IPTW), (3) PS matching, (4) evaluating balance of confounding variables between exposure groups, and (5) conducting LCA using the weighted or matched data set.

RESULTS

Based on the results of IPTW which compared the low, medium and high risk classes of metabolic syndrome (compared to a class without metabolic syndrome), no association was found between smoking and the metabolic syndrome latent classes. PS matching which compared low and moderate risk classes compared to class without metabolic syndrome, showed that smoking increases the probability of being in the low-risk class of metabolic syndrome (OR: 2.19; 95% CI: 1.32, 3.63). In the unadjusted analysis, smoking increased the chances of being in the low-risk (OR: 1.45; 95% CI: 1.01, 2.08) and moderate-risk (OR: 1.68; 95% CI: 1.18, 2.40) classes of metabolic syndrome compared to the class without metabolic syndrome.

CONCLUSIONS

Based on the results, the causal effect of smoking on latent hazard classes of metabolic syndrome can be different based on the type of PS method. In adjusted analysis, no relationship was observed between smoking and moderate-risk and high-risk classes of metabolic syndrome.

Understanding the prevalence, progression, and management of metabolic syndrome in Saudi Arabia

Metabolic syndrome (MetS) is characterized by the coexistence of several disorders comprising hypertension, abdominal obesity, insulin sensitivity, and dyslipidemia. In recent times, MetS has gained increased attention due to the global prevalence of obesity. Adipose tissue plays a crucial role in this syndrome by releasing various molecules significantly affecting lipid/insulin regulation, oxidative stress, and cardiovascular function. Tumor necrosis factor-α (p-α), an inflammatory cytokine, and adiponectin, an adipose tissue-specific protein, are considered vital adipokines that play a significant role in the pathogenesis of MetS. The impact of dietary ingredients on MetS management has been extensively studied over the past few decades. These plant-derived natural chemicals have demonstrated beneficial impacts on obesity, diabetes, and cardiovascular disease (CVD) due to their diverse properties. Saudi Arabia has a high prevalence of overweight and diabetes, but there has been limited research on the incidence of MetS in the country. As a result, in this review, we evaluated the prevalence of MetS in Saudi Arabia and its associated risk factors, as well as explored the mechanisms of progression of MetS and the role of natural phytochemicals in the prevention of MetS.

Risk Factors for Premature Coronary Heart Disease in Women Compared to Men: Systematic Review and Meta-Analysis

Background: We aimed to systematically examine literature on the prevalence of known modifiable and nonmodifiable risk factors for premature coronary heart disease (PCHD) in women compared with men. Materials and Methods: PubMed, CINAHL, Embase, and Web of Science databases were searched. Review protocol is registered in PROSPERO (CRD42020173216). Quality was assessed using the National Heart, Lung, and Blood Institute tool. Review Manager 5.3 was used for meta-analysis. Effect sizes were expressed as odds ratio (OR) and mean differences/standardized mean differences (SMD) with 95% confidence intervals (CIs) for categorical and continuous variables. Results: In this PCHD cohort (age <65 years), the mean age of presentation in women was 3 years older than men. Women had higher total cholesterol (SMD 0.11; 95% CI 0.00 to 0.23) and higher high-density lipoprotein cholesterol (SMD 0.49; 95% CI 0.29 to 0.69). Women were more likely to have hypertension (OR 1.51, 95% CI 1.42 to 1.60), diabetes mellitus (OR 1.78, 95% CI 1.55 to 2.04), obesity (OR 1.33, 95% CI 1.24 to 1.42), metabolic syndrome (OR 3.73, 95% CI 1.60 to 8.69), stroke (OR 1.63, 95% CI 1.51 to 1.77), peripheral vascular disorder (OR 1.67, 95% CI 1.43 to 1.96), and depression (OR 2.29, 95% CI 1.96 to 2.67). Women were less likely to be smokers (OR 0.60, 95% CI 0.55 to 0.66), have reported alcohol intake (OR 0.36, 95% CI 0.33 to 0.40), and reported use of illicit drug (OR 0.32, 95% CI 0.16 to 0.62). Conclusions: Risk factor profile in PCHD has a clear sex difference that supports early, aggressive, holistic, but sex-specific, approach to prevention.

The role of smoking history in longitudinal changes in C-reactive protein between Black and White older adults in the US

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This study is the first to examine the effect of race and smoking history on changes in CRP.

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Overall, there were no significant effects of race or current cigarette smoking on CRP change.

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In NHWs only, smoking history, education, sex, and BMI were predictive of CRP.

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In NHBs only, only BMI was predictive of CRP.

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NHBs may not experience the same reductions in CRP with smoking cessation as NHWs.

Smoking cessation is associated with decreases in C-reactive protein (CRP), a biomarker of systemic inflammation and cancer risk; yet CRP levels remain higher long-term in individuals who quit vs. those who never smoked. While non-Hispanic, Black/African American (NHB) have higher levels of CRP vs. non-Hispanic, White/Caucasian (NHW) adults, the association between CRP and race has not been examined in individuals with smoking history. Utilizing longitudinal data from the Health and Retirement Study (HRS), the current study examined the effects of race and smoking history on CRP in older adults. NHB (n = 242) and NHW (n = 1529) participants completed HRS assessments in 2006, 2010, and 2014. Dried blood spots collected at each wave were assayed for CRP. Linear mixed models were used to examine the effect of race and smoking history on CRP across waves – controlling for sociodemographics, physical activity, body mass index (BMI), and current smoking. Overall, results showed no significant effects of race or current smoking on CRP; rather age, sex, education, BMI, physical activity, smoking history, and time × race predicted CRP (ps<.04). However, while age, sex, education, BMI, physical activity, and smoking history were also predictive of CRP in NHWs (ps<.04) in race-stratified models, only BMI was a significant predictor of CRP in NHBs (p=.012). BMI may be important in explaining inflammation-related disease risk in NHBs with a history of smoking. NHBs may not experience the same reductions in CRP with smoking cessation as NHWs – potentially contributing to tobacco-related health disparities.

Sex Differences in Risk Factors for Metabolic Syndrome in the Korean Population

With an increase in the obese population, the prevalence of metabolic syndrome is increasing in Korea. This study aimed to identify sex- and age-specific risk factors for metabolic syndrome. A secondary data analysis was performed using the Korean National Health and Nutritional Examination Survey. Participants comprised 6144 adults aged 20-79 years. The prevalence of metabolic syndrome was high in the middle- and old-aged men (31.9% and 34.5%, respectively) and in old-aged women (39.1%). Risk factors for metabolic syndrome showed different patterns for men and women. In men, alcohol drinking was identified as the main risk factor for hypertension (odds ratio (OR); young = 3.3 vs. middle age = 2.0), high triglycerides (young = 2.4 vs. middle age = 2.2), and high fasting blood sugar (middle age = 1.6). In women, the main risk factors were household income and education level, showing different patterns in different age groups. In conclusion, the vulnerable groups at high risk of metabolic syndrome are those of middle-aged men and women. The pattern of risk factors is sex-specific.

Warranty Period of a Calcium Score of Zero: Comprehensive Analysis From MESA

OBJECTIVES

This study sought to quantify and model conversion of a normal coronary artery calcium (CAC) scan to an abnormal CAC scan.

BACKGROUND

Although the absence of CAC is associated with excellent prognosis, progression to CAC >0 confers increased risk. The time interval for repeated scanning remains poorly defined.

METHODS

This study included 3,116 participants from the MESA (Multi-Ethnic Study of Atherosclerosis) with baseline CAC = 0 and follow-up scans over 10 years after baseline. Prevalence of incident CAC, defined by thresholds of CAC >0, CAC >10, or CAC >100, was calculated and time to progression was derived from a Weibull parametric survival model. Warranty periods were modeled as a function of sex, race/ethnicity, cardiovascular risk, and desired yield of repeated CAC testing. Further analysis was performed of the proportion of coronary events occurring in participants with baseline CAC = 0 that preceded and followed repeated CAC testing at different time intervals.

RESULTS

Mean participants' age was 58 ± 9 years, with 63% women, and mean 10-year cardiovascular risk of 14%. Prevalence of CAC >0, CAC >10, and CAC >100 was 53%, 36%, and 8%, respectively, at 10 years. Using a 25% testing yield (number needed to scan [NNS] = 4), the estimated warranty period of CAC >0 varied from 3 to 7 years depending on sex and race/ethnicity. Approximately 15% of participants progressed to CAC >10 in 5 to 8 years, whereas 10-year progression to CAC >100 was rare. Presence of diabetes was associated with significantly shorter warranty period, whereas family history and smoking had small effects. A total of 19% of all 10-year coronary events occurred in CAC = 0 prior to performance of a subsequent scan at 3 to 5 years, whereas detection of new CAC >0 preceded 55% of future events and identified individuals at 3-fold higher risk of coronary events.

CONCLUSIONS

In a large population of individuals with baseline CAC = 0, study data provide a robust estimation of the CAC = 0 warranty period, considering progression to CAC >0, CAC >10, and CAC >100 and its impact on missed versus detectable 10-year coronary heart disease events. Beyond age, sex, race/ethnicity, diabetes also has a significant impact on the warranty period. The study suggests that evidence-based guidance would be to consider rescanning in 3 to 7 years depending on individual demographics and risk profile.

Dual use of electronic and conventional cigarettes is associated with higher cardiovascular risk factors in Korean men

Most smokers who use electronic cigarettes (e-cigarettes) to stop smoking simultaneously use conventional cigarettes (dual users). We aimed to compare the prevalence of cardiovascular risk factors among dual users, cigarette-only smokers, and never smokers in Korean men. We used data acquired from Korean National Health and Nutrition Examination Survey (2013-2017) pertaining to 7,505 male participants aged 19 years or older. About 85% of e-cigarette users were dual users. Dual users had greater nicotine dependence and higher urinary cotinine levels than cigarette-only smokers. Dual users had more psychosocial and behavioural risk factors, including perceived high stress, depressive mood, high daily intake of energy, and obesity, than never smokers and cigarette-only smokers. The prevalence of metabolic syndrome (MetS) was higher among dual users, and their multivariate-adjusted prevalence odds ratio for MetS was 2.79 (P < 0.001) compared with never smokers and 1.57 (P = 0.038) compared with cigarette-only smokers. Given that most e-cigarette users are dual users and dual users are more vulnerable to cardiovascular risk factors than cigarette-only smokers and never smokers, more active treatment for smoking cessation and intensive lifestyle interventions for dual users should be considered with priority.

Associations of tobacco smoking with body mass distribution; a population-based study of 65,875 men and women in midlife

BACKGROUND

Studies indicate an effect of smoking toward abdominal obesity, but few assess hip and waist circumferences (HC and WC) independently. The present study aimed to assess the associations of smoking status and volume smoked with HC and WC and their ratio in a population with low prevalence of obesity together with high prevalence of smoking.

METHODS

We used cross-sectional survey data from 11 of a total 19 Norwegian counties examined in 1997-99 including 65,875 men and women aged 39-44 years. Analysis of associations were adjusted for confounding by socioeconomic position, health indicators, and additionally for BMI.

RESULTS

Compared with never-smokers, when adjusting for confounders and in addition for BMI, mean HC remained lower while mean WC and waist-hip-ratio (WHR) were higher in current smokers. The finding of a lower HC and higher WHR level among smokers was consistent by sex and in strata by levels of education and physical activity, while the finding of higher WC by smoking was less consistent. Among current smokers, BMI-adjusted mean HC decreased whereas WC and WHR increased by volume smoked. Compared with current smokers, former smokers had higher BMI-adjusted HC, lower WHR and among women WC was lower.

CONCLUSIONS

The main finding in this study was the consistent negative associations of smoking with HC. In line with the hypothesis that lower percentage gluteofemoral fat is linked with higher cardiovascular risk, our results suggest that smoking impacts cardiovascular risk through mechanisms that reduce the capacity of fat storage in the lower body region.

Prevalence and associations of behavioural risk factors with blood lipids profile in Lebanese adults: findings from WHO STEPwise NCD cross-sectional survey

OBJECTIVE

To examine associations of behavioural risk factors, namely cigarette smoking, physical activity, dietary intakes and alcohol consumption, with blood lipids profile.

DESIGN AND PARTICIPANTS

Data drawn from a cross-sectional study involving participants aged 18 years and over (n=363) from the nationwide WHO STEPwise Nutrition and Non-communicable Disease Risk Factor survey in Lebanon.

MEASURES

Demographic characteristics, behaviours and medical history were obtained from participants by questionnaire. Dietary assessment was performed using a 61-item Culture-Specific Food Frequency Questionnaire that measured food intake over the past year. Lipid levels were measured by the analysis of fasting blood samples (serum total cholesterol (TC), triglycerides (TG), very low-density lipoprotein (VLDL), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C)).

RESULTS

Current cigarette smoking, alcohol consumption and low physical activity were prevalent among 33.3%, 39.7% and 41.6% of the sample, respectively. The contributions of fat and saturated fat to daily energy intake were high, estimated at 36.5% and 11.4%, respectively. Abnormal levels of TC, TG, VLDL, LDL-C and HDL-C were observed for 55.4%, 31.4%, 29.2%, 47.5% and 21.8% of participants, respectively. Adjusting for potential confounders, cigarette smoking was positively associated with higher odds of TG and VLDL (OR=4.27; 95% CI 1.69 to 10.77; and 3.26; 95% CI 1.33 to 8.03, respectively) with a significant dose-response relationship (p value for trend=0.010 and 0.030, respectively). Alcohol drinking and high saturated fat intake (≥10% energy intake) were associated with higher odds of LDL-C (OR=1.68; 95% CI 1.01 to 2.82 and OR= 1.73; 95% CI 1.02 to 2.93). Physical activity did not associate significantly with any blood lipid parameter.

CONCLUSION

The demonstrated positive associations between smoking, alcohol drinking and high saturated fat intake with adverse lipoprotein levels lay further evidence for clinical practitioners, public health professionals and dietitians in the development of preventive strategies among subjects with a high risk of cardiovascular diseases in Lebanon and other neighbouring countries with similar epidemiological profile.

Impact of combined lifestyle factors on metabolic syndrome in Korean men

Background

The purpose of this study was to determine the relationship between combined poor lifestyle factors and metabolic syndrome (MetS) in Korean men.

Methods

Data from the Korean National Health and Nutrition Examination Survey 2010 were classified according to the number and combination patterns of poor lifestyle factors, namely, current smoking, high-risk alcohol use, low physical activity and poor dietary habits. We analyzed the association between the combined poor lifestyle factors and MetS. The definition of MetS was based on the joint interim statement of the International Diabetes Federation Task Force on Epidemiology and Prevention in 2009.

Results

A total of 1408 men aged 20-75 were included in this study. Approximately one-third of the 30-49 age group had ≥3 combined poor lifestyle factors. Compared with those with no poor lifestyle factors, the ORs for MetS were 3.57 (95% CI 1.16-11.02), 3.62 (95% CI 1.18-11.08) and 6.31 (95% CI 2.08-19.26) in subjects with one, two and three or more poor lifestyle factors, respectively. When current smoking, high-risk alcohol use and low physical activity were concurrently present, the ORs for MetS, hyperglycemia, and hypertriglyceridemia were 14.32 (95% CI 3.64-56.30), 4.49 (95% CI 1.62-12.40), and 5.07 (95% CI 2.18-11.81), respectively.

Conclusions

Comprehensive lifestyle modifications need to be stressed in public health programs.

Lifestyle recommendations for the prevention and management of metabolic syndrome: an international panel recommendation

The importance of metabolic syndrome (MetS) lies in its associated risk of cardiovascular disease and type 2 diabetes, as well as other harmful conditions such as nonalcoholic fatty liver disease. In this report, the available scientific evidence on the associations between lifestyle changes and MetS and its components is reviewed to derive recommendations for MetS prevention and management. Weight loss through an energy-restricted diet together with increased energy expenditure through physical activity contribute to the prevention and treatment of MetS. A Mediterranean-type diet, with or without energy restriction, is an effective treatment component. This dietary pattern should be built upon an increased intake of unsaturated fat, primarily from olive oil, and emphasize the consumption of legumes, cereals (whole grains), fruits, vegetables, nuts, fish, and low-fat dairy products, as well as moderate consumption of alcohol. Other dietary patterns (Dietary Approaches to Stop Hypertension, new Nordic, and vegetarian diets) have also been proposed as alternatives for preventing MetS. Quitting smoking and reducing intake of sugar-sweetened beverages and meat and meat products are mandatory. Nevertheless, there are inconsistencies and gaps in the evidence, and additional research is needed to define the most appropriate therapies for MetS. In conclusion, a healthy lifestyle is critical to prevent or delay the onset of MetS in susceptible individuals and to prevent cardiovascular disease and type 2 diabetes in those with existing MetS. The recommendations provided in this article should help patients and clinicians understand and implement the most effective approaches for lifestyle change to prevent MetS and improve cardiometabolic health.

Disparities in Cardiovascular Disease and Type 2 Diabetes Risk Factors in Blacks and Whites: Dissecting Racial Paradox of Metabolic Syndrome

Cardiovascular diseases (CVD) remain as the leading cause of mortality in the western world and have become a major health threat for developing countries. There are several risk factors that account for the CVD and the associated mortality. These include genetics, type 2 diabetes (T2DM), obesity, physical inactivity, hypertension, and abnormal lipids and lipoproteins. The constellation of these risk factors has been termed metabolic syndrome (MetS). MetS varies among racial and ethnic populations. Thus, race and ethnicity account for some of the differences in the MetS and the associated CVD and T2DM. Furthermore, the relationships among traditional metabolic parameters and CVD differ, especially when comparing Black and White populations. In this regard, the greater CVD in Blacks than Whites have been partly attributed to other non-traditional CVD risk factors, such as subclinical inflammation (C-reactive protein), homocysteine, increased low-density lipoprotein oxidation, lipoprotein a, adiponectin, and plasminogen activator inhibitor-1, etc. Thus, to understand CVD and T2DM differences in Blacks and Whites with MetS, it is essential to explore the contributions of both traditional and non-traditional CVD and T2DM risk factors in Blacks of African ancestry and Whites of Europoid ancestry. Therefore, in this mini review, we propose that non-traditional risk factors should be integrated in defining MetS as a predictor of CVD and T2DM in Blacks in the African diaspora in future studies.

Synergistic and Non-synergistic Associations for Cigarette Smoking and Non-tobacco Risk Factors for Cardiovascular Disease Incidence in the Atherosclerosis Risk In Communities (ARIC) Study

INTRODUCTION

Cigarette smoking, various metabolic and lipid-related factors and hypertension are well-recognized cardiovascular disease (CVD) risk factors. Since smoking affects many of these factors, use of a single imprecise smoking metric, for example, ever or never smoked, may allow residual confounding and explain inconsistencies in current assessments of interactions.

METHODS

Using a comprehensive model in pack-years and cigarettes/day for the complex smoking-related relative risk (RR) of CVD to reduce residual confounding, we evaluated interactions with non-tobacco risk factors, including additive (non-synergistic) and multiplicative (synergistic) forms. Data were from the prospective Atherosclerosis Risk in Communities (ARIC) Study from four areas of the United States recruited in 1987-1989 with follow-up through 2008. Analyses included 14 127 participants, 207 693 person-years and 2857 CVD events.

RESULTS

Analyses revealed distinct interactions with smoking: including statistical consistency with additive (body mass index [BMI], waist to hip ratio [WHR], diabetes mellitus [DM], glucose, insulin, high density lipoproteins [HDL] and HDL(2)); and multiplicative (hypertension, total cholesterol [TC], low density lipoproteins [LDLs], apolipoprotein B [apoB], TC to HDL ratio and HDL(3)) associations, as well as indeterminate (apolipoprotein A-I [apoA-I] and triglycerides) associations.

CONCLUSIONS

The forms of the interactions were revealing but require confirmation. Improved understanding of joint associations may help clarify the public health burden of smoking for CVD, links between etiologic factors and biological mechanisms, and the consequences of joint exposures, whereby synergistic associations highlight joint effects and non-synergistic associations suggest distinct contributions.

IMPLICATIONS

Joint associations for cigarette smoking and non-tobacco risk factors were distinct, revealing synergistic/multiplicative (hypertension, TC, LDL, apoB, TC/HDL, HDL(3)), non-synergistic/additive (BMI, WHR, DM, glucose, insulin, HDL, HDL(2)) and indeterminate (apoA-I and TRIG) associations. If confirmed, these results may help better define the public health burden of smoking on CVD risk and identify links between etiologic factors and biologic mechanisms, where synergistic associations highlight joint impacts and non-synergistic associations suggest distinct contributions from each factor.

Association between the Time of Length since Smoking Cessation and Insulin Resistance in Asymptomatic Korean Male Ex-Smokers

AIM

Smoking is a major risk factor for diabetes mellitus, mainly due to decreased insulin secretion and increased insulin resistance. However, there has been little research on the effects of smoking cessation period on changes in insulin resistance. In this study, we investigated the relationships between the length of time since smoking cessation period and insulin resistance in asymptomatic Korean male ex-smokers.

METHODS

A total of 851 male adults were included in this study. We considered several factors that can affect insulin resistance, and through multiple linear regression analysis, we assessed the effect the length of time since smoking cessation on insulin resistance in ex-smokers. Insulin resistance was represented as the insulin resistance index estimated by homeostasis model assessment.

RESULTS

HOMA-IR values showed a statistically significant negative correlation with the length of time since smoking cessation (p = 0.009) in ex-smokers. After performing multiple linear regression analysis using factors that could potentially influence insulin resistance, we found that waist circumference (p = 0.026) and the length of time since smoking cessation (p = 0.039) were independent predictors of HOMA-IR in asymptomatic male ex-smokers.

CONCLUSION

The longer the smoking cessation period, the more the insulin resistance tended to decrease in asymptomatic Korean male ex-smokers.

Smoking status and abdominal obesity among normal- and overweight/obese adults: Population-based FINRISK study

Several studies have reported direct associations of smoking with body mass index (BMI) and abdominal obesity. However, the interplay between them is poorly understood. Our first aim was to investigate the interaction between smoking status and BMI on abdominal obesity (waist circumference, WC). Our second aim was to examine how the association of smoking status with WC varies among normal and overweight/obese men and women. We examined 5833 participants from the National FINRISK 2007 Study. The interactions between smoking and BMI on WC were analyzed. Participants were categorized into eight groups according to BMI (normal weight vs. overweight/obese) and smoking status (never smoker, ex-smoker, occasional/light/moderate daily smoker, heavy daily smoker). The associations between each BMI/smoking status -group and WC were analyzed by multiple regressions, the normal-weight never smokers as the reference group. The smoking status by BMI-interaction on WC was significant for women, but not for men. Among the overweight/obese women, ex-smokers (β = 2.73; 1.99, 3.46) and heavy daily smokers (β = 4.90; 3.35, 6.44) had the highest estimates for WC when adjusted for age, BMI, alcohol consumption and physical activity. In comparison to never smoking overweight/obese women, the β-coefficients of ex-smokers and heavy daily smokers were significantly higher. Among men and normal weight women the β -coefficients did not significantly differ by smoking status. An interaction between smoking status and BMI on abdominal obesity was observed in women: overweight/obese heavy daily smokers were particularly vulnerable for abdominal obesity. This risk group should be targeted for cardiovascular disease prevention.

Prevalence and Associated Factors of Insulin Resistance in Adults from Maracaibo City, Venezuela

Background and Aim. Insulin resistance (IR) is a prominent pathophysiologic component in a myriad of metabolic disorders, including obesity, prediabetes, and type 2 diabetes mellitus, which are common in our locality. The objective of this study was to determine the prevalence of IR and factors associated with this condition in an adult population from Maracaibo city, Venezuela. Methodology. A cross-sectional, descriptive study with multistaged randomized sampling was carried out in 2026 adults. IR was defined as HOMA2-IR ≥ 2. A multiple logistic regression model was constructed in order to evaluate factors associated with IR. Results. The prevalence of IR was 46.5% (n = 943), with 46.7% (n = 450) in the general population, 46.4% (n = 493) in females, and 47.90% (n = 970) in males (p = 0.895). IR prevalence tended to increase with age and was significantly greater in subjects aged ≥30 years (χ (2) = 16.726; p = 2.33 × 10(-4)). Employment, alcohol consumption, obesity, high triacylglycerides, low HDL-C, and dysglycemia were associated with greater odds of IR, whereas a high level of physical activity appeared to be weak protective factor against IR. Conclusions. The prevalence of IR is elevated in our locality. The main determinants of this condition appear to be the presence of obesity, high triacylglycerides, low HDL-C, dysglycemia, and alcohol intake.

Prevalence, associated factors and heritabilities of metabolic syndrome and its individual components in African Americans: the Jackson Heart Study

OBJECTIVE

Both environmental and genetic factors play important roles in the development of metabolic syndrome (MetS). Studies about its associated factors and genetic contribution in African Americans (AA) are sparse. Our aim was to report the prevalence, associated factors and heritability estimates of MetS and its components in AA men and women.

PARTICIPANTS AND SETTING

Data of this cross-sectional study come from a large community-based Jackson Heart Study (JHS). We analysed a total of 5227 participants, of whom 1636 from 281 families were part of a family study subset of JHS.

METHODS

Participants were classified as having MetS according to the Adult Treatment Panel III criteria. Multiple logistic regression analysis was performed to isolate independently associated factors of MetS (n=5227). Heritability was estimated from the family study subset using variance component methods (n=1636).

RESULTS

About 27% of men and 40% of women had MetS. For men, associated factors with having MetS were older age, lower physical activity, higher body mass index, and higher homocysteine and adiponectin levels (p<0.05 for all). For women, in addition to all these, lower education, current smoking and higher stress were also significant (p<0.05 for all). After adjusting for covariates, the heritability of MetS was 32% (p<0.001). Heritability ranged from 14 to 45% among its individual components. Relatively higher heritability was estimated for waist circumference (45%), high density lipoprotein-cholesterol (43%) and triglycerides (42%). Heritability of systolic blood pressure (BP), diastolic BP and fasting blood glucose was 16%, 15% and 14%, respectively.

CONCLUSIONS

Stress and low education were associated with having MetS in AA women, but not in men. Higher heritability estimates for lipids and waist circumference support the hypothesis of lipid metabolism playing a central role in the development of MetS and encourage additional efforts to identify the underlying susceptibility genes for this syndrome in AA.

Distribution and burden of newly detected coronary artery calcium: Results from the Multi-Ethnic Study of Atherosclerosis

BACKGROUND

The transition from no coronary artery calcium (CAC) to detectable CAC is important, as even mild CAC is associated with increased cardiovascular events. We sought to characterize the anatomic distribution and burden of newly detectable CAC over 10-year follow-up.

METHODS

We evaluated 3112 participants (mean age, 58 years; 64% female) with baseline CAC = 0 from the Multi-Ethnic Study of Atherosclerosis. Participants underwent repeat CAC testing at different time intervals (between 2-10 years after baseline) per the Multi-Ethnic Study of Atherosclerosis protocol. Among participants who developed CAC on a follow-up scan, we used logistic regression and marginal probability modeling to describe the coronary distribution and burden of new CAC by age, sex, and race after adjustment for cardiovascular risk factors and time to detection.

RESULTS

A total of 1125 participants developed detectable CAC during follow-up with a mean time to detection of 6.1 ± 3 years. New CAC was most commonly isolated to 1 vessel (72% of participants), with the left anterior descending artery (44% of total) most commonly affected followed by the right coronary (12%), left circumflex (10%), and left main (6%). These patterns were similar across age, sex, and race. In multivariate models, residual predictors of multivessel CAC (28% of total) included male sex, African American or Hispanic race, hypertension, obesity, and diabetes. At the first detection of CAC >0, burden was usually low with median Agatston CAC score of 7.1 and <5% with CAC scores >100.

CONCLUSION

New-onset CAC most commonly involves just 1 vessel, occurs in the left anterior descending artery, and has low CAC burden. New CAC can be detected at an early stage when aggressive preventive strategies may provide benefit.

Psychosocial Predictors of Metabolic Syndrome among Latino Groups in the Multi-Ethnic Study of Atherosclerosis (MESA)

OBJECTIVE

We sought to determine the contribution of psychological variables to risk for metabolic syndrome (MetS) among Latinos enrolled in the Multi-Ethnic Study of Atherosclerosis (MESA), and to investigate whether social support moderates these associations, and whether inflammatory markers mediate the association between psychological variables and MetS.

RESEARCH DESIGN AND METHODS

Cross-sectional analyses at study baseline were conducted with a national Latino cohort (n = 1,388) that included Mexican Americans, Dominican Americans, Puerto Rican Americans and Central/South Americans. Hierarchical logistic regression analyses were conducted to test the effects of psychosocial variables (chronic stress, depressive symptoms, and social support) on MetS. In addition, separate subgroup-specific models, controlling for nationality, age, gender, socioeconomic position, language spoken at home, exercise, smoking and drinking status, and testing for the effects of chronic stress, depressive symptoms and inflammation (IL-6, CRP, fibrinogen) in predicting risk for MetS were conducted.

RESULTS

In the overall sample, high chronic stress independently predicted risk for MetS, however this association was found to be significant only in Mexican Americans and Puerto Rican Americans. Social support did not moderate the associations between chronic stress and MetS for any group. Chronic stress was not associated with inflammatory markers in either the overall sample or in each group.

CONCLUSIONS

Our results suggest a differential contribution of chronic stress to the prevalence of MetS by national groups.

Metabolic syndrome: Risk factors among adults in Kingdom of Saudi Arabia

Background:

Metabolic syndrome (MetS) is a cluster of established cardiovascular risk factors that collectively increase predisposition to major chronic diseases, including heart diseases and diabetes mellitus. Citizens of developing countries such as Saudi Arabia are at risk for MetS as a result of industrialization and accessibility to fast foods. In this epidemiologic study, the kingdom-wide prevalence of MetS is determined.

Materials and Methods:

A total of 4578 Saudis aged 15-64 was randomly selected from 20 regions in Saudi Arabia. Anthropometrics were collected, and fasting blood samples collected to ascertain fasting blood glucose and lipid profile. Components of full MetS as defined by the International Diabetes Federation were used for screening.

Results:

The overall prevalence of MetS is 28.3%. Prevalence was significantly higher in males than in females (31.4 vs. 25.2%; P = 0.001). Prevalence of MetS was the highest in the northern and central region, and showed a parallel increase with age, and inversely with educational status. Region was also a significant contributor to MetS. Conclusion: Despite accumulating evidence of an epidemic, MetS remains largely unresolved in the kingdom. Aggressive public campaign should be launched, and policies implemented to control any future damage of MetS in the kingdom.

Rotation thromboelastometry and the hypercoagulable state in Cushing's syndrome

INTRODUCTION

Rotation thromboelastometry (ROTEM®) can be used for hypercoagulability evaluation. Cushing's syndrome (CS) is associated with hypercoagulability; however, ROTEM® has never been evaluated in this setting.

OBJECTIVE

To evaluate hypercoagulability in CS using ROTEM® and to correlate these parameters with coagulation markers and with the presence of deep vein thrombosis.

DESIGN AND METHODS

Thirty patients with active CS (26 women) and 30 controls matched for age, sex, body mass index, diabetes mellitus, arterial hypertension, ABO blood group and smoking were included. We measured levels of activated partial thromboplastin time (aPTT), platelets, fibrinogen, D-dimer, factor VIII (FVIII), von Willebrand factor (vWF) and C-reactive protein. ROTEM® was used to evaluate the intrinsic (INTEM), extrinsic (EXTEM) and fibrinogen (FIBTEM) pathways. Doppler ultrasonography was performed to search for lower limbs deep vein thrombosis.

RESULTS

INTEM clotting time using ROTEM® was shorter in patients than in controls (P = 0·04). Other ROTEM® parameters were not different. Mean aPTT was shorter in patients than in controls (P = 0·001). The FVIII, vWF and D-dimer levels were higher in patients than in controls (P = 0·001, 0·001 and 0·02, respectively). Obese CS patients presented higher levels of platelets and alterations in maximum clot formation (MCF), alpha angle and maximum speed of clot formation of INTEM (P = 0·03, 0·02 and 0·02, respectively) and an increase in the MCF of FIBTEM (P = 0·02). No deep vein thrombosis was found.

CONCLUSIONS

Although FVIII and vWF were abnormal in CS patients, only the initiation clot formation was different in the ROTEM® methodology and no deep vein thrombosis was found.

Cancer risk among gingivitis and periodontitis patients: a nationwide cohort study

AIM

Periodontal disease encompasses gingivitis and periodontitis, which exerts systemic effects. We conducted a population-based study to evaluate the association between periodontal disease and the risk of cancer.

METHODS

We used insurance claims data from 1997 to 2010, accessing a database of 1 million randomly selected insurants in Taiwan. All patients were older than 20 and newly diagnosed with periodontitis between 1 January 1997 and 31 December 2010. The comparison cohort comprised patients older than 20, who were newly diagnosed with gingivitis in the same period. Both cohorts were followed until a cancer diagnosis, lost to follow-up, death, termination of insurance, or the end of 2010.

RESULTS

The incidence rate of cancer was 1.14 times higher in the study cohort than in the comparison cohort [confidence interval (CI) = 1.11-1.17]. The adjusted hazard ratio (HR) was 1.05 (95% CI = 1.00-1.11). A multivariable analysis showed that the periodontitis patients exhibited an elevated risk of developing oral cancer (adjusted HR = 1.79, 95% CI = 1.42-2.25).

CONCLUSION

The findings indicated that patients in the periodontitis cohort exhibited a higher risk of developing oral cancer than those in the gingivitis cohort.

Associations between smoking, components of metabolic syndrome and lipoprotein particle size

BACKGROUND

The clustering of metabolic and cardiovascular risk factors is known as metabolic syndrome (MetS). The risk of having MetS is strongly associated with increased adiposity and can be further modified by smoking behavior. Apolipoproteins (apo) associated with low-density lipoprotein-cholesterol (LDL-C) and high-density lipoprotein-cholesterol (HDL-C) may be altered in MetS. This study aimed to examine the association between smoking and the following parameters: MetS and its components, levels of apolipoproteins and estimated lipoprotein particle size, separately for men and women, and in different body mass index (BMI) classes.

METHODS

We included 24,389 men and 35,078 women aged between 18 and 80 years who participated in the LifeLines Cohort Study between December 2006 and January 2012; 5,685 men and 6,989 women were current smokers. Participants were categorized into three different body mass index (BMI) classes (BMI <25; BMI 25 to 30; BMI ≥30 kg/m²). MetS was defined according to the National Cholesterol Education Program's Adult Treatment Panel III (NCEP:ATPIII) criteria. Blood pressure, anthropometric and lipid measurements were rigorously standardized, and the large sample size enabled a powerful estimate of quantitative changes. The association between smoking and the individual MetS components, and apoA1 and apoB, was tested with linear regression. Logistic regression was used to examine the effect of smoking and daily tobacco smoked on risk of having MetS. All models were age adjusted and stratified by sex and BMI class.

RESULTS

Prevalence of MetS increased with higher BMI levels. A total of 64% of obese men and 42% of obese women had MetS. Current smoking was associated with a higher risk of MetS in both sexes and all BMI classes (odds ratio 1.7 to 2.4 for men, 1.8 to 2.3 for women, all P values <0.001). Current smokers had lower levels of HDL cholesterol and apoA1, higher levels of triglycerides and apoB, and higher waist circumference than non-smokers (all P <0.001). Smoking had no consistent association with blood pressure or fasting blood glucose. In all BMI classes, we found a dose-dependent association of daily tobacco consumption with MetS prevalence as well as with lower levels of HDL cholesterol, higher triglyceride levels and lower ratios of HDL cholesterol/apoA1 and, only in those with BMI <30, LDL cholesterol/apoB (all P <0.001).

CONCLUSIONS

Smoking is associated with an increased prevalence of MetS, independent of sex and BMI class. This increased risk is mainly related to lower HDL cholesterol, and higher triglycerides and waist circumference. In addition, smoking was associated with unfavorable changes in apoA1 and apoB, and in lipoprotein particle size. Please see related commentary: http://www.biomedcentral.com/1741-7015/11/196.

Association Between MTHFR Gene Polymorphisms, Smoking, and the Incidence of Vascular Dementia

This study investigated the relationship between N5,N10-methylene tetrahydrofolic acid reductase (MTHFR) polymorphisms, smoking, and vascular dementia (VD). Polymerase chain reaction-restriction fragment length polymorphism analysis was used to analyze the frequency of the C/T polymorphism at position 677 of the MTHFR gene in 304 VD patients and 300 control patients with nondementia cerebral infarction. The CC, CT, and TT genotype frequencies of the MTHFR gene were 43.42%, 32.57%, and 24.01%, respectively, in the VD group, and 50.67%, 32.00%, and 17.33%, respectively, in the control group. The T allele frequency was significantly higher in the VD group than in the control group ( P < .05). Among patients who smoked, the relative risk of VD in patients with the TT genotype and T allele was higher than in the control group ( P < .05). Therefore, the smoking group with the T allele has the highest risk of VD, and synergy appears to exist between the MTHFR gene polymorphisms and smoking in susceptibility to VD.