Characterization of myocardial injury phenotype by thermal liquid biopsy

Background and aims

With the advent and implementation of high-sensitivity cardiac troponin assays, differentiation of patients with distinct types of myocardial injuries, including acute thrombotic myocardial infarction (TMI), acute non-thrombotic myocardial injury (nTMi), and chronic coronary atherosclerotic disease (cCAD), is of pressing clinical importance. Thermal liquid biopsy (TLB) emerges as a valuable diagnostic tool, relying on identifying thermally induced conformational changes of biomolecules in blood plasma. While TLB has proven useful in detecting and monitoring several cancers and autoimmune diseases, its application in cardiovascular diseases remains unexplored. In this proof-of-concept study, we sought to determine and characterize TLB profiles in patients with TMI, nTMi, and cCAD at multiple acute-phase time points (T 0 h, T 2 h, T 4 h, T 24 h, T 48 h) as well as a follow-up time point (Tfu) when the patient was in a stable state.

Methods

TLB profiles were collected for 115 patients (60 with TMI, 35 with nTMi, and 20 with cCAD) who underwent coronary angiography at the event presentation and had subsequent follow-up. Medical history, physical, electrocardiographic, histological, biochemical, and angiographic data were gathered through medical records, standardized patient interviews, and core laboratory measurements.

Results

Distinctive signatures were noted in the median TLB profiles across the three patient types. TLB profiles for TMI and nTMi patients exhibited gradual changes from T0 to Tfu, with significant differences during the acute and quiescent phases. During the quiescent phase, all three patient types demonstrated similar TLB signatures. An unsupervised clustering analysis revealed a unique TLB signature for the patients with TMI. TLB metrics generated from specific features of TLB profiles were tested for differences between patient groups. The first moment temperature (TFM) metric distinguished all three groups at time of presentation (T0). In addition, 13 other TLB-derived metrics were shown to have distinct distributions between patients with TMI and those with cCAD.

Conclusion

Our findings demonstrated the use of TLB as a sensitive and data-rich technique to be explored in cardiovascular diseases, thus providing valuable insight into acute myocardial injury events.

Prognostic performance of the IABP-SHOCK II Risk Score among cardiogenic shock subtypes in the critical care cardiology trials network registry

BACKGROUND

Risk stratification has potential to guide triage and decision-making in cardiogenic shock (CS). We assessed the prognostic performance of the IABP-SHOCK II score, derived in Europe for acute myocardial infarct-related CS (AMI-CS), in a contemporary North American cohort, including different CS phenotypes.

METHODS

The critical care cardiology trials network (CCCTN) coordinated by the TIMI study group is a multicenter network of cardiac intensive care units (CICU). Participating centers annually contribute ≥2 months of consecutive medical CICU admissions. The IABP-SHOCK II risk score includes age > 73 years, prior stroke, admission glucose > 191 mg/dl, creatinine > 1.5 mg/dl, lactate > 5 mmol/l, and post-PCI TIMI flow grade < 3. We assessed the risk score across various CS etiologies.

RESULTS

Of 17,852 medical CICU admissions 5,340 patients across 35 sites were admitted with CS. In patients with AMI-CS (n = 912), the IABP-SHOCK II score predicted a >3-fold gradient in in-hospital mortality (low risk = 26.5%, intermediate risk = 52.2%, high risk = 77.5%, P < .0001; c-statistic = 0.67; Hosmer-Lemeshow P = .79). The score showed a similar gradient of in-hospital mortality in patients with non-AMI-related CS (n = 2,517, P < .0001) and mixed shock (n = 923, P < .001), as well as in left ventricular (<0.0001), right ventricular (P = .0163) or biventricular (<0.0001) CS. The correlation between the IABP-SHOCK II score and SOFA was moderate (r2 = 0.17) and the IABP-SHOCK II score revealed a significant risk gradient within each SCAI stage.

CONCLUSIONS

In an unselected international multicenter registry of patients admitted with CS, the IABP- SHOCK II score only moderately predicted in-hospital mortality in a broad population of CS regardless of etiology or irrespective of right, left, or bi-ventricular involvement.

Optimal Screening for Predicting and Preventing the Risk of Heart Failure Among Adults With Diabetes Without Atherosclerotic Cardiovascular Disease: A Pooled Cohort Analysis

BACKGROUND

The optimal approach to identify individuals with diabetes who are at a high risk for developing heart failure (HF) to inform implementation of preventive therapies is unknown, especially in those without atherosclerotic cardiovascular disease (ASCVD).

METHODS

Adults with diabetes and no HF at baseline from 7 community-based cohorts were included. Participants without ASCVD who were at high risk for developing HF were identified using 1-step screening strategies: risk score (WATCH-DM [Weight, Age, Hypertension, Creatinine, HDL-C, Diabetes Control, QRS Duration, MI, and CABG] ≥12), NT-proBNP (N-terminal pro-B-type natriuretic peptide ≥125 pg/mL), hs-cTn (high-sensitivity cardiac troponin T ≥14 ng/L; hs-cTnI ≥31 ng/L), and echocardiography-based diabetic cardiomyopathy (echo-DbCM; left atrial enlargement, left ventricular hypertrophy, or diastolic dysfunction). High-risk participants were also identified using 2-step screening strategies with a second test to identify residual risk among those deemed low risk by the first test: WATCH-DM/NT-proBNP, NT-proBNP/hs-cTn, NT-proBNP/echo-DbCM. Across screening strategies, the proportion of HF events identified, 5-year number needed to treat and number needed to screen to prevent 1 HF event with an SGLT2i (sodium-glucose cotransporter 2 inhibitor) among high-risk participants, and cost of screening were estimated.

RESULTS

The initial study cohort included 6293 participants (48.2% women), of whom 77.7% without prevalent ASCVD were evaluated with different HF screening strategies. At 5-year follow-up, 6.2% of participants without ASCVD developed incident HF. The 5-year number needed to treat to prevent 1 HF event with an SGLT2i among participants without ASCVD was 43 (95% CI, 29-72). In the cohort without ASCVD, high-risk participants identified using 1-step screening strategies had a low 5-year number needed to treat (22 for NT-proBNP to 37 for echo-DbCM). However, a substantial proportion of HF events occurred among participants identified as low risk using 1-step screening approaches (29% for echo-DbCM to 47% for hs-cTn). Two-step screening strategies captured most HF events (75-89%) in the high-risk subgroup with a comparable 5-year number needed to treat as the 1-step screening approaches (30-32). The 5-year number needed to screen to prevent 1 HF event was similar across 2-step screening strategies (45-61). However, the number of tests and associated costs were lowest for WATCH-DM/NT-proBNP ($1061) compared with other 2-step screening strategies (NT-proBNP/hs-cTn: $2894; NT-proBNP/echo-DbCM: $16 358).

CONCLUSIONS

Selective NT-proBNP testing based on the WATCH-DM score efficiently identified a high-risk primary prevention population with diabetes expected to derive marked absolute benefits from SGLT2i to prevent HF.

Restrictive or Liberal Transfusion Strategy in Myocardial Infarction and Anemia

BACKGROUND

A strategy of administering a transfusion only when the hemoglobin level falls below 7 or 8 g per deciliter has been widely adopted. However, patients with acute myocardial infarction may benefit from a higher hemoglobin level.

METHODS

In this phase 3, interventional trial, we randomly assigned patients with myocardial infarction and a hemoglobin level of less than 10 g per deciliter to a restrictive transfusion strategy (hemoglobin cutoff for transfusion, 7 or 8 g per deciliter) or a liberal transfusion strategy (hemoglobin cutoff, <10 g per deciliter). The primary outcome was a composite of myocardial infarction or death at 30 days.

RESULTS

A total of 3504 patients were included in the primary analysis. The mean (±SD) number of red-cell units that were transfused was 0.7±1.6 in the restrictive-strategy group and 2.5±2.3 in the liberal-strategy group. The mean hemoglobin level was 1.3 to 1.6 g per deciliter lower in the restrictive-strategy group than in the liberal-strategy group on days 1 to 3 after randomization. A primary-outcome event occurred in 295 of 1749 patients (16.9%) in the restrictive-strategy group and in 255 of 1755 patients (14.5%) in the liberal-strategy group (risk ratio modeled with multiple imputation for incomplete follow-up, 1.15; 95% confidence interval [CI], 0.99 to 1.34; P = 0.07). Death occurred in 9.9% of the patients with the restrictive strategy and in 8.3% of the patients with the liberal strategy (risk ratio, 1.19; 95% CI, 0.96 to 1.47); myocardial infarction occurred in 8.5% and 7.2% of the patients, respectively (risk ratio, 1.19; 95% CI, 0.94 to 1.49).

CONCLUSIONS

In patients with acute myocardial infarction and anemia, a liberal transfusion strategy did not significantly reduce the risk of recurrent myocardial infarction or death at 30 days. However, potential harms of a restrictive transfusion strategy cannot be excluded. (Funded by the National Heart, Lung, and Blood Institute and others; MINT ClinicalTrials.gov number, NCT02981407.).

E-Cigarette Use Among US Adults in the 2021 Behavioral Risk Factor Surveillance System Survey

Importance

After the initial disruption from the COVID-19 pandemic, it is unclear how patterns of e-cigarette use in the US have changed.

Objective

To examine recent patterns in current and daily e-cigarette use among US adults in 2021.

Design, Setting, and Participants

This cross-sectional study used data from the 2021 Behavioral Risk Factor Surveillance System (BRFSS) database. The BRFSS is the largest national telephone-based survey of randomly sampled adults in the US. Adults aged 18 years or older, residing in 49 US states (all except Florida), the District of Columbia, and 3 US territories (Guam, Puerto Rico, and the US Virgin Islands), were included in the data set. Data analysis was performed in January 2023.

Main Outcomes and Measures

The main outcome was age-adjusted prevalence of current and daily e-cigarette use overall and by participant characteristics, state, and territory. Descriptive statistical analysis was conducted, applying weights to account for population representation.

Results

This study included 414 755 BRFSS participants with information on e-cigarette use. More than half of participants were women (51.3%). In terms of race and ethnicity, 0.9% of participants were American Indian or Alaska Native, 5.8% were Asian, 11.5% were Black, 17.3% were Hispanic, 0.2% were Native Hawaiian or Other Pacific Islander, 62.2% were White, 1.4% were of multiple races or ethnicities, and 0.6% were of other race or ethnicity. Individuals aged 18 to 24 years comprised 12.4% of the study population. The age-standardized prevalence of current e-cigarette use was 6.9% (95% CI, 6.7%-7.1%), with almost half of participants using e-cigarettes daily (3.2% [95% CI, 3.1%-3.4%]). Among individuals aged 18 to 24 years, there was a consistently higher prevalence of e-cigarette use, with more than 18.6% reporting current use and more than 9.0% reporting daily use. Overall, among individuals reporting current e-cigarette use, 42.2% (95% CI, 40.7%-43.7%) indicated former combustible cigarette use, 37.1% (95% CI, 35.6%-38.6%) indicated current combustible cigarette use, and 20.7% (95% CI, 19.7%-21.8%) indicated never using combustible cigarettes. Although relatively older adults (aged ≥25 years) who reported current e-cigarette use were more likely to report former or current combustible cigarette use, younger adults (aged 18-24 years) were more likely to report never using combustible cigarettes. Notably, the proportion of individuals who reported current e-cigarette use and never using combustible cigarettes was higher in the group aged 18 to 20 years (71.5% [95% CI, 66.8%-75.7%]) compared with those aged 21 to 24 years (53.0% [95% CI, 49.8%-56.1%]).

Conclusion and Relevance

These findings suggest that e-cigarette use remained common during the COVID-19 pandemic, particularly among young adults aged 18 to 24 years (18.3% prevalence). Notably, 71.5% of individuals aged 18 to 20 years who reported current e-cigarette use had never used combustible cigarettes. These results underscore the rationale for the implementation and enforcement of public health policies tailored to young adults.

Association of Electronic Cigarette Exposure on Cardiovascular Health: A Systematic Review and Meta-Analysis

Despite the growing use of electronic cigarettes (EC) in the Unites States, particularly among young people, and their perceived safety, current evidence suggests that EC usage may cause adverse clinical cardiovascular effects. Therefore, we aim to pool all studies evaluating the association of EC exposure with cardiovascular health. Medline, Cochrane CENTRAL, and Scopus were searched for studies from January 1, 2006 until December 31, 2022. Randomized and observational studies reporting cardiovascular outcomes, hemodynamic parameters, and biomarkers of platelet physiology, before and after acute or chronic EC exposure were pooled using a random-effects model. Overall, 27 studies (n = 863) were included. Heart rate increased significantly after acute EC exposure (weighted mean difference [WMD]: 0.76 bpm; 95% confidence interval [CI], 0.48, 1.03; P < 0.00001; I2 = 92%). Significant increases in systolic blood pressure (WMD: 0.28 mmHg; 95% CI, 0.06, 0.51; P = 0.01; I2 = 94%), diastolic blood pressure (WMD: 0.38 mmHg; 95% CI, 0.16, 0.60; P = 0.0006; I2 = 90%), and PWV (WMD: 0.38; 95% CI, 0.13, 0.63; P = 0.003; I2 = 100%) were also observed. Augmentation index increased significantly (SMD: 0.39; 95% CI, 0.11, 0.67; P = 0.007; I2 = 90%), whereas reduction in flow-mediated dilation (WMD: -1.48; 95% CI, -2.49, -0.47; P = 0.004; I2 = 45%) was observed. Moreover, significant rise in both soluble P-selectin (WMD: 4.73; 95% CI, 0.80, 8.66; P = 0.02; I2 = 98%) and CD40L (WMD: 1.14; 95% CI, 0.41, 1.87; P = 0.002; I2 = 79%) was observed. Our results demonstrate that smoking EC is associated with a significant increase in cardiovascular hemodynamic measures and biomarkers. Our findings can aid policymakers in making informed decisions regarding the regulation of EC to ensure public safety.

Investigating the association of traditional and non-traditional tobacco product use with subclinical and clinical cardiovascular disease: The Cross-Cohort Collaboration-Tobacco working group rationale, design, and methodology

While the impact of combustible cigarette smoking on cardiovascular disease (CVD) is well-established, the longitudinal association of non-traditional tobacco products with subclinical and clinical CVD has not been fully explored due to: 1) limited data availability; and 2) the lack of well-phenotyped prospective cohorts. Therefore, there is the need for sufficiently powered well-phenotyped datasets to fully elucidate the CVD risks associated with non-cigarette tobacco products. The Cross-Cohort Collaboration (CCC)-Tobacco is a harmonized dataset of 23 prospective cohort studies predominantly in the US. A priori defined variables collected from each cohort included baseline characteristics, details of traditional and non-traditional tobacco product use, inflammatory markers, and outcomes including subclinical and clinical CVD. The definitions of the variables in each cohort were systematically evaluated by a team of two physician-scientists and a biostatistician. Herein, we describe the method of data acquisition and harmonization and the baseline sociodemographic and risk profile of participants in the combined CCC-Tobacco dataset. The total number of participants in the pooled cohort is 322782 (mean age: 59.7 ± 11.8 years) of which 76% are women. White individuals make up the majority (73.1%), although there is good representation of other race and ethnicity groups including African American (15.6%) and Hispanic/Latino individuals (6.4%). The prevalence of participants who never smoked, formerly smoked, and currently smoke combustible cigarettes is 50%, 36%, and 14%, respectively. The prevalence of current and former cigar, pipe, and smokeless tobacco is 7.3%, 6.4%, and 8.6%, respectively. E-cigarette use was measured only in follow-up visits of select studies, totaling 1704 former and current users. CCC-Tobacco is a large, pooled cohort dataset that is uniquely designed with increased power to expand knowledge regarding the association of traditional and non-traditional tobacco use with subclinical and clinical CVD, with extension to understudied groups including women and individuals from underrepresented racial-ethnic groups.

Comprehensive review of the national surveys that assess E-cigarette use domains among youth and adults in the United States

Surveillance of e-cigarette use among different population groups is important for the timely implementation and evaluation of tobacco regulatory policies. In this review, we identified 13 nationally representative, repeatedly conducted epidemiologic surveys that assess e-cigarette use among U.S. youth and/or adults and have been instrumental in e-cigarette surveillance. These surveys included National Youth Tobacco Survey, Youth Risk Behavior Surveillance System, Monitoring the Future Survey, International Tobacco Control Policy Evaluation Project (ITC) Youth Tobacco and Vaping Survey, Behavioral Risk Factor Surveillance System, National Health Interview Survey, Tobacco Use Supplement of the Current Population Survey, Health Information National Trends Survey, Tobacco Products and Risk Perception Surveys, ITC Four Country Smoking and Vaping Survey, National Health and Nutrition Examination Survey, National Survey on Drug Use and Health, and Population Assessment of Tobacco and Health. These surveys vary in scope and detail, with their unique strengths and the regulatory questions that can be answered using each survey data. We also highlighted the gaps in these surveys and made recommendations for improvement.

Psychosocial stressors and current e-cigarette use in the youth risk behavior survey

BACKGROUND

This study explores the association between psychosocial stressors and current e-cigarette use among adolescents in the United States.

METHODS

We used data from 12,767 participants in the 2019 National Youth Risk Behavioral Survey to examine the association between psychosocial stressors (bullying, sexual assault, safety-related absence from school, depressive symptoms, suicidal ideation, physical altercation, and weapon threats) and past-30-day e-cigarette use using multivariable-adjusted logistic regression models. We examined the association for each stressor and then as a burden score (0-7). To compare the strength of the association between stressors and current e-cigarette use to current combustible cigarette use, we additionally examined the association between each stressor and current combustible cigarette use.

RESULTS

Approximately 32.7% reported current e-cigarette use. The weighted prevalence of current e-cigarette use was higher among individuals who experienced stressors than those who did not. For example, bullying (43.9% vs. 29.0%). Similar prevalence patterns were seen among other stressors. Individuals who experienced stressors had significantly higher adjusted odds of current e-cigarette use than those who did not (OR [Odds Ratio] range: 1.47-1.75). Similarly, individuals with higher burden scores had a higher prevalence (zero [20.5%], one [32.8%], two [41.4%], three [49.6%], four to seven [60.9%]) and higher odds of current e-cigarette use (OR range: 1.43-2.73) than those with a score of zero. The strength of the association between the stressors and e-cigarette use was similar to that between the stressors and combustible cigarette use.

CONCLUSION

The study demonstrates a significant association between psychosocial stressors and adolescent e-cigarette use, highlighting the potential importance of interventions, such as targeted school-based programs that address stressors and promote stress management, as possible means of reducing adolescent e-cigarette use. Future research directions include exploring underlying mechanisms linking stressors to e-cigarette use and evaluating the effectiveness of interventions addressing stressors in reducing adolescent e-cigarette use.

Risk factor associations with individual myocardial infarction subtypes and acute non-ischemic myocardial injury in the Multi-Ethnic Study of Atherosclerosis (MESA): Design and rationale

BACKGROUND

Despite different prevalence, pathobiology, and prognosis between etiologically distinct myocardial infarction (MI) subtypes, prospective study of risk factor for MI in large NHLBI-sponsored cardiovascular cohorts is limited to acute MI as a singular entity. Therefore, we sought to utilize the Multi-Ethnic Study of Atherosclerosis (MESA), a large prospective primary prevention cardiovascular study, to define the incidence and risk factor profile of individual myocardial injury subtypes.

METHODS

We describe the rationale and design of re-adjudicating 4,080 events that occurred over the first 14 years of follow-up in MESA for the presence and subtype of myocardial injury as defined by the Fourth Universal Definition of MI: MI type 1 to 5, acute non-ischemic myocardial injury, and chronic myocardial injury. The project utilizes a 2-physician adjudication process via examination of medical records, abstracted data collection forms, cardiac biomarker results, and electrocardiograms of all relevant clinical events. Comparison of the magnitude and direction of associations between baseline traditional and novel cardiovascular risk factors with incident and recurrent acute MI subtypes and acute non-ischemic myocardial injury events will be made.

CONCLUSIONS

This project will result in one of the first large prospective cardiovascular cohort with modern classification of acute MI subtypes, as well as a full accounting of non-ischemic myocardial injury events, with implications for numerous ongoing and future studies in MESA. By creating precise MI phenotypes, and defining their epidemiology, this project will allow for discovery of novel pathobiology-specific risk factors, allow for development of more accurate risk prediction, and suggest more targeted preventive strategies.

Patterns of tobacco product use and substance misuse among adolescents in the United States

Among adolescents, sole use is the most common pattern of e-cigarette use. However, concurrent use of e-cigarettes with other tobacco products is not uncommon and may be associated with high-risk behaviors. We used data from 12,767 participants in the 2019 Youth Risk Behavior Survey to examine the patterns of tobacco product use among youth in the US. First, we examined the prevalence of e-cigarette-specific patterns of tobacco use (nonuse[no tobacco product use], sole use[sole e-cigarette use], dual-use[e-cigarette and one other tobacco product], and poly use[e-cigarette and two or more other tobacco products]). Then, using multivariable Poisson regression, we assessed how the tobacco use patterns were associated with the misuse of nine substances of abuse (alcohol, marijuana, cocaine, ecstasy, hallucinogens, heroin, inhalants, injectables, and methamphetamines). 62.9% of youth reported nonuse of any tobacco product. The weighted prevalence of sole e-cigarette use, dual use, and poly use was 23.2%, 4.2%, and 3.3%, respectively. Across all the substances explored, the prevalence was highest among poly users, followed by dual users, sole users, and non-users. Compared to non-users, sole, dual, and poly users had 7.8(95 %CI:6.1-10.0), 14.3(95 %CI:10.8-18.8), and 19.7(95 %CI:15.0-25.9) times higher adjusted prevalence of reporting past-30-day binge drinking, after adjusting for age, sex, race/ethnicity, sexual orientation, and depressive symptoms. This pattern was seen across all the different substances explored. These findings highlight the high prevalence of substance misuse among youth who use tobacco products and the need to educate and counsel on substances of abuse among this population, particularly among poly-tobacco users.

Blood Levels of Angiotensinogen and Hypertension in the Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

Angiotensinogen is the proximal precursor of the angiotensin peptide hormones of the renin-angiotensin-aldosterone system (RAAS). Clinical trials are ongoing targeting angiotensinogen for the treatment of hypertension and heart failure. The epidemiology of angiotensinogen is not well defined, particularly its relationship to ethnicity, sex, and blood pressure (BP)/hypertension.

OBJECTIVES

The authors sought to determine the relationship of circulating angiotensinogen levels to ethnicity, sex, BP, incident hypertension, and prevalent hypertension in a modern sex-balanced ethnically diverse cohort.

METHODS

Plasma angiotensinogen levels were measured in 5,786 participants from the MESA (Multi-Ethnic Study of Atherosclerosis). Linear, logistic, and Cox proportional hazards models were utilized to examine the associations of angiotensinogen with BP, prevalent hypertension, and incident hypertension, respectively.

RESULTS

Angiotensinogen levels were significantly higher in females than males and differed across self-reported ethnicities with the ordering (from highest to lowest): White, Black, Hispanic, and Chinese adults. Higher levels were associated with higher BP and odds of prevalent hypertension, after adjusting for other risk factors. Equivalent relative differences in angiotensinogen were associated with greater differences in BP in males vs females. In males not taking RAAS-blocking medications, a standard deviation increment in log-angiotensinogen was associated with 2.61 mm Hg higher systolic BP (95% CI: 1.49-3.80), while in females the same increment in angiotensinogen was associated with 0.97 mm Hg higher systolic BP (95% CI: 0.30-1.65).

CONCLUSIONS

Significant differences in angiotensinogen levels are present between sexes and ethnicities. A positive association is present between levels and prevalent hypertension and BP, which differs between sexes.

Pod-based e-cigarette use among US college-aged adults: A survey on the perception of health effects, sociodemographic correlates, and interplay with other tobacco products

INTRODUCTION

E-cigarette use among youth and young adults remains of public health concern. Pod-based e-cigarettes, including JUUL, significantly changed the e-cigarette landscape in the US. Using an online survey, we explored the socio-behavioral correlates, predisposing factors, and addictive behaviors, among young adult pod-mod users within a University in Maryland, USA.

METHODS

In total, 112 eligible college students aged 18-24 years, recruited from a University in Maryland, who reported using pod-mods were included in this study. Participants were categorized into current/non-current users based on past-30-day use. Descriptive statistics were used to analyze participants' responses.

RESULTS

The mean age of the survey participants was 20.5 ± 1.2 years, 56.3% were female, 48.2% White, and 40.2% reported past-30-day (current) use of pod-mods. The mean age of first experimentation with pod-mods was 17.8 ± 1.4 years, while the mean age of regular use was 18.5 ± 1.4 years, with the majority (67.9%) citing social influence as the reason for initiation. Of the current users, 62.2% owned their own devices, and 82.2% predominantly used JUUL and menthol flavor (37.8%). A significant proportion of current users (73.3%) reported buying pods in person, 45.5% of whom were aged <21 years. Among all participants, 67% had had a past serious quit attempt. Among them, 89.3% neither used nicotine replacement therapy nor prescription medications. Finally, current use (adjusted odds ratio, AOR=4.52; 95% CI: 1.76-11.64), JUUL use (AOR=2.56; 95% CI: 1.08-6.03), and menthol flavor (AOR=6.52; 95% CI: 1.38-30.89) were associated with reduced nicotine autonomy, a measure of addiction.

CONCLUSIONS

Our findings provide specific data to inform the development of public health interventions targeted at college youth, including the need for more robust cessation support for pod-mod users.

Rationale and design for the myocardial ischemia and transfusion (MINT) randomized clinical trial

BACKGROUND

Accumulating evidence from clinical trials suggests that a lower (restrictive) hemoglobin threshold (<8 g/dL) for red blood cell (RBC) transfusion, compared with a higher (liberal) threshold (≥10 g/dL) is safe. However, in anemic patients with acute myocardial infarction (MI), maintaining a higher hemoglobin level may increase oxygen delivery to vulnerable myocardium resulting in improved clinical outcomes. Conversely, RBC transfusion may result in increased blood viscosity, vascular inflammation, and reduction in available nitric oxide resulting in worse clinical outcomes. We hypothesize that a liberal transfusion strategy would improve clinical outcomes as compared to a more restrictive strategy.

METHODS

We will enroll 3500 patients with acute MI (type 1, 2, 4b or 4c) as defined by the Third Universal Definition of MI and a hemoglobin <10 g/dL at 144 centers in the United States, Canada, France, Brazil, New Zealand, and Australia. We randomly assign trial participants to a liberal or restrictive transfusion strategy. Participants assigned to the liberal strategy receive transfusion of RBCs sufficient to raise their hemoglobin to at least 10 g/dL. Participants assigned to the restrictive strategy are permitted to receive transfusion of RBCs if the hemoglobin falls below 8 g/dL or for persistent angina despite medical therapy. We will contact each participant at 30 days to assess clinical outcomes and at 180 days to ascertain vital status. The primary end point is a composite of all-cause death or recurrent MI through 30 days following randomization. Secondary end points include all-cause mortality at 30 days, recurrent adjudicated MI, and the composite outcome of all-cause mortality, nonfatal recurrent MI, ischemia driven unscheduled coronary revascularization (percutaneous coronary intervention or coronary artery bypass grafting), or readmission to the hospital for ischemic cardiac diagnosis within 30 days. The trial will assess multiple tertiary end points.

CONCLUSIONS

The MINT trial will inform RBC transfusion practice in patients with acute MI.

Angiotensinogen: More Than its Downstream Products: Evidence From Population Studies and Novel Therapeutics

The renin-angiotensin-aldosterone system (RAAS) is a well-defined pathway playing a key role in maintaining circulatory homeostasis. Abnormal activation of RAAS contributes to development of cardiovascular disease, including heart failure, cardiac hypertrophy, hypertension, and atherosclerosis. Although several key RAAS enzymes and peptide hormones have been thoroughly investigated, the role of angiotensinogen-the precursor substrate of the RAAS pathway-remains less understood. The study of angiotensinogen single-nucleotide polymorphisms (SNPs) has provided insight into associations between angiotensinogen and hypertension, congestive heart failure, and atherosclerotic cardiovascular disease. Targeted drug therapy of RAAS has dramatically improved clinical outcomes for patients with heart failure, myocardial infarction, and hypertension. However, all such therapeutics block RAAS components downstream of angiotensinogen and elicit compensatory pathways that limit their therapeutic efficacy as monotherapy. Upstream RAAS targeting by an angiotensinogen inhibitor has the potential to be more efficacious in patients with suboptimal RAAS inhibition and has a better safety profile than multiagent RAAS blockade. Newly developed therapeutics that target angiotensinogen through antisense oligonucleotides or silencer RNA technologies are providing a novel perspective into the pathobiology of angiotensinogen and show promise as the next frontier in the treatment of cardiovascular disease.

The Interplay of Race/Ethnicity and Obesity on the Incidence of Venous Thromboembolism

INTRODUCTION

Factors predisposing asymptomatic individuals within the community to venous thromboembolism are not fully understood. This study characterizes the incidence and determinants of venous thromboembolism among the Multiethnic Study of Atherosclerosis cohort with a focus on race/ethnicity and obesity.

METHODS

This study (analyzed in 2020-2021) used the Multiethnic Study of Atherosclerosis cohort (2000-2017), which included participants with diverse ethnic/racial backgrounds aged 45-84 years without cardiovascular disease at baseline. The primary endpoint was time to diagnosis of venous thromboembolism defined using International Classification of Diseases codes (415, 451, 453, 126, 180, and 182). Multivariable-adjusted hazard ratios of the predictors of venous thromboembolism were calculated with a focus on the interaction between obesity and race/ethnicity categories.

RESULTS

Over a median follow-up period of 14 years, 233 individuals developed venous thromboembolism. Incidence rates (per 1,000 person-years) varied across racial/ethnic groups with the highest incidence among Black (4.02) followed by White (2.98), Hispanic (2.08), and Chinese (0.79) participants. There was a stepwise increase in the incidence rate of venous thromboembolism with increasing BMI regardless of race/ethnicity: normal (1.95), overweight (2.52), obese (3.63), and morbidly obese (4.55). The association between BMI and venous thromboembolism was strongest among non-White women with the highest incidence rate for obese (4.8) compared with non-obese (1.6). The interaction among obesity, gender, and race was statistically significant (p=0.01) in non-White obese women. Risk of venous thromboembolism increased with age for all race/ethnicities.

CONCLUSIONS

This study finds that obesity may confer an increased risk for venous thromboembolism among non-White women compared with other groups-White men, White women, and non-White men.

Assessment of Patterns in e-Cigarette Use Among Adults in the US, 2017-2020

IMPORTANCE

Updated data on the patterns of e-cigarette use among adults in the US are needed.

OBJECTIVE

To examine recent patterns in current and daily e-cigarette use among US adults.

DESIGN, SETTING, AND PARTICIPANTS

This repeated cross-sectional study used data from the 2017, 2018, and 2020 Behavioral Risk Factor Surveillance System, a nationally representative state-based survey of noninstitutionalized US adults. A total of 994 307 adults 18 years and older who were living in states and territories that provided data on e-cigarette use in 2017 (53 states and territories), 2018 (36 states and Guam), and 2020 (42 states and Guam) were included.

MAIN OUTCOMES AND MEASURES

The weighted prevalence of current (past 30 days) and daily e-cigarette use was estimated for each year, and changes in prevalence from 2017 to 2020 were assessed, first overall and then stratified by participant characteristics, including state or territory of residence.

RESULTS

Among 994 307 adults from states with data on e-cigarette use, 429 370 individuals (weighted 51.3% female) were participants in the 2017 survey, 280 184 (weighted 52.1% female) were participants in the 2018 survey, and 284 753 (weighted 52.1% female) were participants in the 2020 survey. The weighted proportions of young adults aged 18 to 24 years were 12.6% in 2017, 11.8% in 2018, and 11.9% in 2020. Across all 3 years, 17 035 participants (weighted, 1.0%) were American Indian or Alaska Native, 22 313 (weighted, 4.6%) were Asian, 75 780 (weighted, 12.2%) were Black, 72 190 (weighted, 15.1%) were Hispanic, 4817 (weighted, 0.2%) were Native Hawaiian, 757 140 (weighted, 65.1%) were White, 20 332 (weighted, 1.3%) were multiracial, and 6245 (weighted, 0.5%) were of other races and/or ethnicities. The prevalence of current e-cigarette use was 4.4% (95% CI, 4.3%-4.5%) in 2017, which increased to 5.5% (95% CI, 5.4%-5.7%) in 2018 and decreased slightly to 5.1% (95% CI, 4.9%-5.3%) in 2020. The recent decrease, though modest, was observed mainly among young adults aged 18 to 20 years (from 18.9% [95% CI, 17.2%-20.7%] to 15.6% [95% CI, 14.1%-17.1%]; P = .004). However, the prevalence of daily e-cigarette use increased consistently from 1.5% (95% CI, 1.4%-1.6%) in 2017 to 2.1% (95% CI, 2.0%-2.2%) in 2018 and 2.3% (95% CI, 2.2%-2.4%) in 2020. Among young adults aged 21 to 24 years, there was a slight, albeit insignificant, increase in the prevalence of current e-cigarette use (from 13.5% [95% CI, 12.3%-14.7%] to 14.5% [95% CI, 13.2%-15.9%]; P = .28) but a significant increase in the prevalence of daily e-cigarette use (from 4.4% [95% CI, 3.8%-5.1%] to 6.6% [95% CI, 5.6%-7.6%]; P < .001) between 2018 and 2020. State-level patterns in the prevalence of current e-cigarette use were heterogeneous, with states like Massachusetts (from 5.6% [95% CI, 4.8%-6.5%] to 4.1% [95% CI, 3.1%-5.3%]; P = .03) and New York (from 5.4% [95% CI, 4.9%-5.9%] to 4.1% [95% CI, 3.5%-4.7%]; P = .001) recording significant decreases between 2018 and 2020. In contrast, Guam (from 5.9% [95% CI, 4.5%-7.9%] to 11.4% [95% CI, 8.7%-14.8%]; P = .002) and Utah (from 6.1% [95% CI, 5.5%-6.7%] to 7.2% [95% CI, 6.5%-8.0%]; P = .02) recorded significant increases in current e-cigarette use over the same period.

CONCLUSIONS AND RELEVANCE

In this study, a slight decrease in the prevalence of current e-cigarette use was found between 2018 and 2020; this decrease was mainly observed among young adults aged 18 to 20 years. In contrast, daily e-cigarette use consistently increased, particularly among young adults aged 21 to 24 years. This increase in daily use suggests greater nicotine dependence among those who use e-cigarettes, warranting continued surveillance.

Association of Electronic Cigarette Use with Respiratory Symptom Development among U.S. Young Adults

Rationale: Electronic cigarette (e-cigarette) use is highly prevalent among young adults. However, longitudinal data assessing the association between e-cigarette use and respiratory symptoms are lacking. Objectives: To determine whether e-cigarette use is associated with the development of respiratory symptoms in young adults. Methods: Data are derived from the PATH (Population Assessment of Tobacco and Health) study waves 2 (2014-2015), 3 (2015-2016), 4 (2016-2018), and 5 (2018-2019). Young adults aged 18-24 years at baseline with no prevalent respiratory disease or symptoms were included in the analyses. Binary logistic regression models with a generalized estimating equation were used to estimate time-varying and time-lagged associations of e-cigarette use during waves 2-4, with respiratory symptom development approximately 12 months later at waves 3-5. Measurements and Main Results: The per-wave prevalence of former and current e-cigarette use was 15.2% and 5.6%, respectively. Former e-cigarette use was associated with higher odds of developing any respiratory symptom (adjusted odds ratio [aOR], 1.20; 95% confidence interval [CI], 1.04-1.39) and wheezing in the chest (aOR, 1.41; 95% CI, 1.08-1.83) in multivariable adjusted models. Current e-cigarette use was associated with higher odds for any respiratory symptom (aOR, 1.32; 95% CI, 1.06-1.65) and wheezing in the chest (aOR, 1.51; 95% CI, 1.06-2.14). Associations persisted among participants who never smoked combustible cigarettes. Conclusions: In this nationally representative cohort of young adults, former and current e-cigarette use was associated with higher odds of developing wheezing-related respiratory symptoms, after accounting for cigarette smoking and other combustible tobacco product use.

In-vivo platelet activation and aggregation during and after acute atherothrombotic myocardial infarction in patients with and without Type-2 diabetes mellitus treated with ticagrelor

INTRODUCTION

Patients with type-2 diabetes are twice as likely to suffer from acute myocardial infarction (AMI) and have a higher incidence of recurrent events than their non-diabetic counterparts. Ticagrelor is a platelet inhibitor known to reduce major adverse cardiovascular events (MACE) in AMI patients. This study measures the level and change in platelet activation and aggregation at the time of and following an AMI in patients with and without diabetes treated with ticagrelor.

MATERIALS/METHODS

P₂Y₁₂ receptor inhibitor naïve patients presenting with AMI were prospectively enrolled. Blood collection occurred before coronary angiography (baseline: T₀), 2, 4, 24, 48 h after baseline, and at a three-month follow-up. Ticagrelor was administered within five minutes of T₀. We assessed platelet activation via measurements of surface P-selectin and platelet activated glycoprotein IIb/IIIa-1 (PAC-1) and assessed platelet aggregation via monocyte, lymphocyte, and granulocyte aggregates. We hypothesize that platelet activation and aggregation will be proportionally impacted to the same degree by ticagrelor, regardless of diabetes status.

RESULTS

Ninety-seven patients were prospectively enrolled (diabetes, N = 33; no diabetes, N = 64). No difference was observed in the expression of P-selectin and PAC-1 at any given point between diabetes and non-diabetes groups (p > 0.05). No difference was observed in the percentage of platelet bound to leukocytes at any measured timepoint between patients with and without diabetes (p > 0.05). Platelet leukocyte aggregation was suppressed during the acute phase compared to quiescence equally among both groups.

DISCUSSION

Ticagrelor demonstrated similar in-vivo effects on platelet activation and aggregation regardless of diabetes status in patients presenting with AMI.

Atherothrombotic factors and atherosclerotic cardiovascular events: the multi-ethnic study of atherosclerosis

AIMS

Traditional atherosclerotic cardiovascular disease (ASCVD) risk factors fail to address the full spectrum of the complex interplay of atherosclerotic and atherothrombotic factors integral to ASCVD events. This study sought to examine the association between atherothrombotic biomarkers and ASCVD events.

METHODS AND RESULTS

The association between atherothrombotic biomarkers and 877 ASCVD events with and without adjustment for traditional risk factors was evaluated via Cox proportional hazards models and factor analysis in 5789 Multi-Ethnic Study of Atherosclerosis participants over a median follow-up of 14.7 years. Factor analysis accounted for multidimensional relationship and shared variance among study biomarkers, which identified two new variables: a thrombotic factor (Factor 1), principally defined by shared variance in fibrinogen, plasmin-antiplasmin complex, factor VIII, D-dimer, and lipoprotein(a), and a fibrinolytic factor (Factor 2), principally defined by shared variance of plasminogen and oxidized phospholipids on plasminogen. In a model including both factors, the thrombotic factor was associated with the higher risk of ASCVD events [hazard ratio (HR) 1.57, 95% confidence interval (CI) 1.45, 1.70], while the fibrinolytic factor was associated with the lower risk of ASCVD events (HR 0.76, 95% CI 0.70, 0.82), with estimated ASCVD free survival highest for low atherothrombotic Factor 1 and high atherothrombotic Factor 2.

CONCLUSION

Two atherothrombotic factors, one representative of thrombotic propensity and the other representative of fibrinolytic propensity, were significantly and complementarily associated with incident ASCVD events, remained significantly associated with incident ASCVD after controlling for traditional risk factors, and have promise for identifying patients at high ASCVD event risk specifically due to their atherothrombotic profile.

A pragmatic lab-based tool for risk assessment in cardiac critical care: data from the Critical Care Cardiology Trials Network (CCCTN) Registry

AIMS

Contemporary cardiac intensive care unit (CICU) outcomes remain highly heterogeneous. As such, a risk-stratification tool using readily available lab data at time of CICU admission may help inform clinical decision-making.

METHODS AND RESULTS

The primary derivation cohort included 4352 consecutive CICU admissions across 25 tertiary care CICUs included in the Critical Care Cardiology Trials Network (CCCTN) Registry. Candidate lab indicators were assessed using multivariable logistic regression. An integer risk score incorporating the top independent lab indicators associated with in-hospital mortality was developed. External validation was performed in a separate CICU cohort of 9716 patients from the Mayo Clinic (Rochester, MN, USA). On multivariable analysis, lower pH [odds ratio (OR) 1.96, 95% confidence interval (CI) 1.72-2.24], higher lactate (OR 1.40, 95% CI 1.22-1.62), lower estimated glomerular filtration rate (OR 1.26, 95% CI 1.10-1.45), and lower platelets (OR 1.18, 95% CI 1.05-1.32) were the top four independent lab indicators associated with higher in-hospital mortality. Incorporated into the CCCTN Lab-Based Risk Score, these four lab indicators identified a 20-fold gradient in mortality risk with very good discrimination (C-index 0.82, 95% CI 0.80-0.84) in the derivation cohort. Validation of the risk score in a separate cohort of 3888 patients from the Registry demonstrated good performance (C-index of 0.82; 95% CI 0.80-0.84). Performance remained consistent in the external validation cohort (C-index 0.79, 95% CI 0.77-0.80). Calibration was very good in both validation cohorts (r = 0.99).

CONCLUSION

A simple integer risk score utilizing readily available lab indicators at time of CICU admission may accurately stratify in-hospital mortality risk.

Multi-Ethnic Study of Atherosclerosis (MESA): JACC Focus Seminar 5/8

The MESA (Multi-Ethnic Study of Atherosclerosis) is a National Heart, Lung, and Blood Institute-sponsored prospective study aimed at studying the prevalence, progression, determinants, and prognostic significance of subclinical cardiovascular disease in a sex-balanced, multiethnic, community-dwelling U.S. cohort. MESA helped usher in an era of noninvasive evaluation of subclinical atherosclerosis presence, burden, and progression for the evaluation of atherosclerotic cardiovascular disease risk, beyond what could be predicted by traditional risk factors alone. Concepts developed in MESA have informed international patient care guidelines, providing new tools to effectively guide public health policy, population screening, and clinical decision-making. MESA is grounded in an open science model that continues to be a beacon for collaborative science. In this review, we detail the original goals of MESA, and describe how the scope of MESA has evolved over time. We highlight 10 significant MESA contributions to cardiovascular medicine, and chart the path forward for MESA in the year 2021 and beyond.

Exposure to volatile organic compounds - acrolein, 1,3-butadiene, and crotonaldehyde - is associated with vascular dysfunction

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of mortality worldwide. Exposure to air pollution, specifically particulate matter of diameter ≤2.5 μm (PM2.5), is a well-established risk factor for CVD. However, the contribution of gaseous pollutant exposure to CVD risk is less clear.

OBJECTIVE

To examine the vascular effects of exposure to individual volatile organic compounds (VOCs) and mixtures of VOCs.

METHODS

We measured urinary metabolites of acrolein (CEMA and 3HPMA), 1,3-butadiene (DHBMA and MHBMA3), and crotonaldehyde (HPMMA) in 346 nonsmokers with varying levels of CVD risk. On the day of enrollment, we measured blood pressure (BP), reactive hyperemia index (RHI - a measure of endothelial function), and urinary levels of catecholamines and their metabolites. We used generalized linear models for evaluating the association between individual VOC metabolites and BP, RHI, and catecholamines, and we used Bayesian Kernel Machine Regression (BKMR) to assess exposure to VOC metabolite mixtures and BP.

RESULTS

We found that the levels of 3HPMA were positively associated with systolic BP (0.98 mmHg per interquartile range (IQR) of 3HPMA; CI: 0.06, 1.91; P = 0.04). Stratified analysis revealed an increased association with systolic BP in Black participants despite lower levels of urinary 3HPMA. This association was independent of PM2.5 exposure and BP medications. BKMR analysis confirmed that 3HPMA was the major metabolite associated with higher BP in the presence of other metabolites. We also found that 3HPMA and DHBMA were associated with decreased endothelial function. For each IQR of 3HPMA or DHBMA, there was a -4.4% (CI: -7.2, -0.0; P = 0.03) and a -3.9% (CI: -9.4, -0.0; P = 0.04) difference in RHI, respectively. Although in the entire cohort the levels of several urinary VOC metabolites were weakly associated with urinary catecholamines and their metabolites, in Black participants, DHBMA levels showed strong associations with urinary norepinephrine and normetanephrine levels.

DISCUSSION

Exposure to acrolein and 1,3-butadiene is associated with endothelial dysfunction and may contribute to elevated risk of hypertension in participants with increased sympathetic tone, particularly in Black individuals.

Cigarette Smoking, Incident Coronary Heart Disease, and Coronary Artery Calcification in Black Adults: The Jackson Heart Study

Background

Although Black adults are more likely to die from coronary heart disease (CHD) compared with White adults, few studies have examined the relationship between cigarette smoking and CHD risk among Black adults. We evaluated the relationship between cigarette smoking, incident CHD, and coronary artery calcification in the JHS (Jackson Heart Study).

Methods and Results

We classified JHS participants without a history of CHD (n=4432) by self‐reported baseline smoking status into current, former (smoked at least 400 cigarettes/life) or never smokers at baseline (2000–2004). We further classified current smokers by smoking intensity (number of cigarettes smoked per day [1–19 or ≥20]) and followed for incident CHD (through 2016). Hazard ratios (HR) for incident CHD for each smoking group compared with never smokers were estimated with adjusted Cox proportional hazard regression models. At baseline, there were 548 (12.4%) current, 782 (17.6%) former, and 3102 (70%) never smokers. During follow‐up (median, 13.8 years), 254 participants developed CHD. After risk factor adjustment, CHD risk was significantly higher in current smokers compared with never smokers (HR, 2.11; 95% CI, 1.39–3.18); the difference between former smokers and never smokers (HR, 1.37; 95% CI, 1.0–1.90) did not achieve statistical significance. Among current smokers, we did not observe a dose‐response effect for CHD risk. Additionally, in multivariable logistic regression models with a subset of our analytic cohort, current smokers had greater odds of coronary artery calcification score >0 compared with never smokers (odds ratio, 2.63; 95% CI, 1.88–3.68).

Conclusions

In a large prospective cohort of Black adults, current smoking was associated with a >2‐fold increased risk of CHD over a median follow‐up of greater than a decade.

Derivation of a Coronary Age Calculator Using Traditional Risk Factors and Coronary Artery Calcium: The Multi-Ethnic Study of Atherosclerosis

Background

The optimal method for communicating coronary heart disease (CHD) risk to individual patients is not yet clear. Recent research supports the concept of "coronary age" for more effective risk communication. We defined an individual's coronary age as the age at which an average healthy individual would have an equivalent estimated CHD risk as that calculated for the index individual, building on our previously validated MESA (Multi‐Ethnic Study of Atherosclerosis) 10‐year CHD Risk Score equations with and without coronary artery calcium (CAC).

Methods and Results

We derived a coronary age by (1) calculating the MESA 10‐year CHD risk; (2) mathematically setting this equal to an equation describing risk of an average healthy MESA participant, as a function of age; and (3) solving for age. The risk discrimination of the resultant coronary age was compared with that of chronological age, the MESA CHD Risk Score, and CAC alone. Approximately 95% of coronary age values ranged from 30 years less to 30 years higher than chronological age. Although the mean chronological age of individuals experiencing CHD events compared with those free of events was 67.4 versus 61.8 years, the difference in coronary age including CAC was larger (80.6 versus 62.8 years). Coronary age with CAC had identical predictive ability to that of MESA CHD Risk Score and outperformed chronological age and CAC alone.

Conclusions

The newly derived coronary age is a convenient transformation of MESA CHD Risk, retaining very good risk discrimination. This easy‐to‐communicate tool will be available for patients and clinicians, potentially facilitating risk communication in routine care.

Residential proximity to greenness mitigates the hemodynamic effects of ambient air pollution

Residential proximity to greenness is associated with a lower risk of cardiovascular disease (CVD) and all-cause mortality. However, it is unclear whether the beneficial effects of greenness are linked to a reduction in the effects of ambient air pollutants. We measured arterial stiffness in 73 participants with moderate to high CVD risk. Average levels of ambient PM2.5 and ozone were calculated from local monitoring stations. Residential greenness was estimated using satellite-derived normalized difference vegetation index (NDVI) for a 200-m and 1-km radius around each participant's home. Participants were 51% female, average age of 52 yr, and 79% had diagnosed hypertension. In multiple linear regression models, residential NDVI was negatively associated with augmentation index (-3.8% per 0.1 NDVI). Ambient levels of PM2.5 [per interquartile range (IQR) of 6.9 μg/m3] were positively associated with augmentation pressure (3.1 mmHg), pulse pressure (5.9 mmHg), and aortic systolic pressure (8.1 mmHg). Ozone (per IQR of 0.03 ppm) was positively associated with augmentation index (5.5%), augmentation pressure (3.1 mmHg), and aortic systolic pressure (10 mmHg). In areas of low greenness, both PM2.5 and ozone were positively associated with pulse pressure. Additionally, ozone was positively associated with augmentation pressure and systolic blood pressure. However, in areas of high greenness, there was no significant association between indices of arterial stiffness with either PM2.5 or ozone. Residential proximity to greenness is associated with lower values of arterial stiffness. Residential greenness may mitigate the adverse effects of PM2.5 and ozone on arterial stiffness.NEW & NOTEWORTHY Previous studies have linked proximity to green spaces with lower cardiovascular disease risk. However, the mechanisms underlying the salutary effects of green areas are not known. In our study of participants at risk of cardiovascular disease, we found that arterial stiffness was positively associated with short-term exposure to PM2.5, PM10, and ozone and inversely associated with greenness. The association between pollution and arterial stiffness was attenuated in areas of high greenness, suggesting that living green neighborhoods can lessen the adverse cardiovascular effects of air pollution.

Smoking Accelerates Atrioventricular Conduction in Humans Concordant with Increased Dopamine Release

Smoking is associated with cardiac arrhythmia, stroke, heart failure, and sudden cardiac arrest, all of which may derive from increased sympathetic influence on cardiac conduction system and altered ventricular repolarization. However, knowledge of the effects of smoking on supraventricular conduction, and the role of the sympathetic nervous system in them, remains incomplete. Participants with intermediate-high cardiovascular disease risk were measured for urinary catecholamines and cotinine, and 12-lead electrocardiograms (ECGs) were measured for atrial and atrioventricular conduction times, including P duration, PR interval, and PR segment (lead II), which were analyzed for associations with cotinine by generalized linear models. Statistical mediation analyses were then used to test whether any significant associations between cotinine and atrioventricular conduction were mediated by catecholamines. ECG endpoints and urinary metabolites were included from a total of 136 participants in sinus rhythm. Atrial and atrioventricular conduction did not significantly differ between smokers (n = 53) and non-smokers (n = 83). Unadjusted and model-adjusted linear regressions revealed cotinine significantly and inversely associated with PR interval and PR segment, but not P duration. Dopamine, norepinephrine, and epinephrine all inversely associated with PR interval, whereas only dopamine was also inversely associated with PR segment (p < 0.05). Dopamine and norepinephrine (but not epinephrine) also associated positively with cotinine. Dopamine mediated the relationship between cotinine and PR interval, as well as the relationship between cotinine and PR segment. Smoking is associated with accelerated atrioventricular conduction and elevated urinary dopamine and norepinephrine. Smoking may accelerate atrioventricular nodal conduction via increased dopamine production.

Protocol to assess the efficacy of carnosine supplementation in mitigating the adverse cardiovascular responses to particulate matter (PM) exposure: the Nucleophilic Defense Against PM Toxicity (NEAT) trial

INTRODUCTION

Exposure to airborne particulate matter (PM) is associated with cardiovascular disease. These outcomes are believed to originate from pulmonary oxidative stress and the systemic delivery of oxidised biomolecules (eg, aldehydes) generated in the lungs. Carnosine is an endogenous di-peptide (β-alanine-L-histidine) which promotes physiological homeostasis in part by conjugating to and neutralising toxic aldehydes. We hypothesise that an increase of endogenous carnosine by dietary supplementation would mitigate the adverse cardiovascular outcomes associated with PM exposure in humans.

METHODS AND ANALYSIS

To test this, we designed the Nucleophilic Defense Against PM Toxicity trial. This trial will enroll 240 participants over 2 years and determine if carnosine supplementation mitigates the adverse effects of PM inhalation. The participants will have low levels of endogenous carnosine to facilitate identification of supplementation-specific outcomes. At enrollment, we will measure several indices of inflammation, preclinical cardiovascular disease and physical function. Participants will be randomly allocated to carnosine or placebo groups and instructed to take their oral supplement for 12 weeks with two return clinical visits and repeated assessments during times of peak PM exposure (June-September) in Louisville, Kentucky, USA. Statistical modelling approaches will be used to assess the efficacy of carnosine supplementation in mitigating adverse outcomes.

ETHICS AND DISSEMINATION

This study protocol has been approved by the Institutional Review Board at the University of Louisville. Results from this study will be disseminated at scientific conferences and in peer-reviewed publications.Trial registration: NCT03314987; Pre-results.

Recurrent Admissions for Acute Decompensated Heart Failure Among Patients With and Without Peripheral Artery Disease: The ARIC Study

Background

Peripheral artery disease (PAD) is both a common comorbidity and a contributing factor to heart failure. Whether PAD is associated with hospitalization for recurrent decompensation among patients with established heart failure is uncertain.

Methods and Results

Since 2005, the ARIC (Atherosclerosis Risk in Communities) study has conducted active surveillance of hospitalized acute decompensated heart failure (ADHF), with events verified by physician review. From 2005 to 2016, 1481 patients were hospitalized with ADHF and discharged alive (mean age, 78 years; 69% White). Of these, 207 (14%) had diagnosis of PAD. Those with PAD were more often men (55% versus 44%) and smokers (17% versus 8%), with a greater prevalence of coronary artery disease (72% versus 52%). Patients with PAD had an increased risk of at least 1 ADHF readmission, both within 30 days (11% versus 7%) and 1 year (39% versus 28%) of discharge from the index hospitalization. After adjustments, PAD was associated with twice the hazard of ADHF readmission within 30 days (HR, 2.02; 95% CI, 1.14–3.60) and a 60% higher hazard of ADHF readmission within 1 year (HR, 1.60; 95% CI, 1.25–2.05). The 1‐year hazard of ADHF readmission associated with PAD was stronger with heart failure with reduced ejection fraction (HR, 2.01; 95% CI, 1.29–3.13) than preserved ejection fraction (HR, 1.04; 95% CI, 0.69–1.56); P for interaction=0.05.

Conclusions

Patients with ADHF and concomitant PAD have a higher likelihood of ADHF readmission. Strategies to prevent ADHF readmissions in this high‐risk group are warranted.

Prevalence, Trends, and Distribution of Nicotine and Marijuana use in E-cigarettes among US adults: The Behavioral Risk Factor Surveillance System 2016-2018

Use of substances other than nicotine in e-cigarettes, especially marijuana, is becoming increasingly popular in the US. However, population-representative data on such poly-use (nicotine and marijuana) remains limited. We therefore conducted a cross-sectional logistic regression analysis of the 2018 Behavioral Risk Factor Surveillance System among 16 US states/territories with data on past 30-day marijuana use to describe the emerging dual nicotine and marijuana vaping population. We additionally examined trends in marijuana use, including marijuana vaping, from 2016 to 2018. Of the 131,807 participants studied, 3068 were current e-cigarette users, among whom 7.1% also vaped marijuana. Prevalence of nicotine-predominant, dual nicotine marijuana, and marijuana-predominant vaping was 3.36%, 0.38% and 1.09%, respectively. Compared to nicotine-predominant vapers, dual and marijuana-predominant vapers were older, had greater proportions of non-Whites, particularly Hispanics, and less likely to be current smokers (nicotine-predominant vs dual vs marijuana-predominant vaping: current tobacco use 44.7 vs 23.7 vs 11.1%). Proportion of dual vapers among current e-cigarette users was 8.6%, 2.6% and 7.1% for 2016, 2017 and 2018, respectively. Prevalence of marijuana use increased from 8.97% (2016) to 13.1% (2018) while no clear trend was observed for marijuana vaping. Dual nicotine and marijuana vaping is prevalent in the US, and compared to predominantly nicotine vapers such users have higher mean ages, and are more likely to be Blacks, Hispanics, and never cigarette smokers. Marijuana use overall increased from 2016 to 2018. Dual vapers represent a large and important emerging population that will require dedicated study of health effects and tailored regulatory strategies.

Characterization of Volatile Organic Compound Metabolites in Cigarette Smokers, Electronic Nicotine Device Users, Dual Users, and Nonusers of Tobacco

INTRODUCTION

Limited research exists about the possible cardiovascular effects of electronic nicotine delivery systems (ENDS). We therefore sought to compare exposure to known or potentially cardiotoxic volatile organic compounds (VOCs) in ENDS users, smokers, and dual users.

METHODS

A total of 371 individuals from the Cardiovascular Injury due to Tobacco Use study, a cross-sectional study of healthy participants aged 21-45 years, were categorized as nonusers of tobacco (n = 87), sole ENDS users (n = 17), cigarette smokers (n = 237), and dual users (n = 30) based on 30-day self-reported tobacco product use patterns. Participants provided urine samples for VOC and nicotine metabolite measurement. We assessed associations between tobacco product use and VOC metabolite measures using multivariable-adjusted linear regression models.

RESULTS

Mean (SD) age of the population was 32 (±6.8) years, 55% men. Mean urinary cotinine level in nonusers of tobacco was 2.6 ng/mg creatinine, whereas cotinine levels were similar across all tobacco product use categories (851.6-910.9 ng/mg creatinine). In multivariable-adjusted models, sole ENDS users had higher levels of metabolites of acrolein, acrylamide, acrylonitrile, and xylene compared with nonusers of tobacco, but lower levels of most VOC metabolites compared with cigarette smokers or dual users. In direct comparison of cigarettes smokers and dual users, we found lower levels of metabolites of styrene and xylene in dual users.

CONCLUSION

Although sole ENDS use may be associated with lower VOC exposure compared to cigarette smoking, further study is required to determine the potential health effects of the higher levels of certain reactive aldehydes, including acrolein, in ENDS users compared with nonusers of tobacco.

IMPLICATIONS

ENDS use in conjunction with other tobacco products may not significantly reduce exposure to VOC, but sole use does generally reduce some VOC exposure and warrants more in-depth studies.

E-Cigarette Use Patterns and High-Risk Behaviors in Pregnancy: Behavioral Risk Factor Surveillance System, 2016-2018

INTRODUCTION

The prevalence of e-cigarette use has increased dramatically in the last decade in the U.S. Understanding the prevalence, patterns of use, and risk factor associations of e-cigarette use in pregnant women is particularly important, as this could have potential health implications for the mother and the developing child.

METHODS

Using Behavioral Risk Factor Surveillance System Survey data from 2016 to 2018, adult women of reproductive age (18-49 years) who reported being pregnant (n=7,434) were studied. Self-reported current e-cigarette use was the main exposure. Other measures included combustible cigarette smoking status and high-risk behaviors (including other tobacco, marijuana, or heavy alcohol use; binge drinking; and others). All analyses were done in 2019.

RESULTS

Approximately 2.2% of pregnant women reported current e-cigarette use, of whom 0.6% reported daily use. The highest prevalence of e-cigarette use was observed in the youngest age group of pregnant women (3.2%), with 41.7% of all pregnant current e-cigarette users being aged 18-24 years. There was a marked increase in the prevalence of current use of e-cigarettes among pregnant women from 1.9% in 2016 to 3.8% in 2018. Approximately 46% of pregnant current e-cigarette users reported concomitant cigarette smoking. Compared with pregnant never e-cigarette users, pregnant current e-cigarette users had a higher prevalence of other tobacco product use, marijuana use, heavy alcohol intake, binge drinking, and other high-risk behaviors.

CONCLUSIONS

These findings underscore the need to strengthen prevention and policy efforts, specifically in the vulnerable subgroup of pregnant women.

Atherosclerotic Cardiovascular Disease Risk Stratification Based on Measurements of Troponin and Coronary Artery Calcium

BACKGROUND

Low values of high-sensitivity cardiac troponin (hs-cTn) and coronary artery calcium (CAC) scores of zero are associated with a low risk for atherosclerotic cardiovascular disease (ASCVD).

OBJECTIVES

The purpose of this study was to evaluate baseline hs-cTnT and CAC in relation to ASCVD.

METHODS

Baseline hs-cTnT (limit of detection [LoD] 3 ng/l) and CAC measurements were analyzed across participants age 45 to 84 years without clinical cardiovascular disease from the prospective MESA (Multi-Ethnic Study of Atherosclerosis) in relationship to incident ASCVD.

RESULTS

Among 6,749 participants, 1,002 ASCVD events occurred during a median follow-up of 15 years. Participants with detectable CAC (20.1 vs. 5.0 events per 1,000 person-years; adjusted hazard ratio [HR]: 2.35; 95% confidence interval [CI]: 2.0 to 2.76; p < 0.001) and detectable hs-cTnT (15.4 vs. 5.2 per 1,000 person-years; adjusted HR: 1.47; 95% CI: 1.21 to 1.77; p < 0.001) had higher rates of ASCVD than those with undetectable results. Individuals with undetectable hs-cTnT (32%) had similar risk for ASCVD as did those with a CAC of zero (50%) (5.2 vs. 5.0 per 1,000 person-years). Together, hs-cTnT and CAC (discordance 38%) resulted in the following ASCVD event rates: hs-cTnT < LoD/CAC = 0: 2.8 per 1,000 person-years (reference), hs-cTnT ≥ LoD/CAC = 0: 6.8 per 1,000 person-years (HR: 1.59; 95% CI: 1.17 to 2.16; p = 0.003), hs-cTnT < LoD/CAC > 0: 11.1 per 1,000 person-years (HR: 2.74; 95% CI: 1.96 to 3.83; p < 0.00001), and hs-cTnT ≥ LoD/CAC > 0: 22.6 per 1,000 person-years (HR: 3.50; 95% CI: 2.60 to 4.70; p < 0.00001).

CONCLUSIONS

An undetectable hs-cTnT identifies patients with a similar, low risk for ASCVD as those with a CAC score of zero. The increased risk among those with discordant results supports their conjoined use for risk prediction.

Flow cytometric evaluation of platelet-leukocyte conjugate stability over time: methodological implications of sample handling and processing

Platelet activation and subsequent aggregation is a vital component of atherothrombosis resulting in acute myocardial infarction. Therefore, quantifying platelet aggregation is a valuable measure for elucidating the pathogenesis of acute coronary syndromes (ACS). Circulating platelet-monocyte conjugates (PMC) as determined by flow cytometry (FCM) are an important measure of in vivo platelet aggregation. However, the influence of sample handling on FCM measurement of PMC is not well-studied. The changes in FCM measurement of PMC with variation in sample handling techniques were evaluated. The stability of PMC concentrations over time with changes in fixation and immunolabeling intervals was assessed. The effect of Time-to-Fix and Time-to-Stain on FCM PMC measurements was investigated in five healthy volunteers. Time-to-Fix (i.e., interval between phlebotomy and sample fixation) was performed at 3, 30, and 60 min. Time-to-Stain (i.e., time of fixed sample storage to staining) was performed at 1, 24, and 48 h. Increasing Time-to-Stain from 1 to 24 or 48 h resulted in lower PMC measures (p < 0.0001). A statistically significant difference in PMC measurement with increasing Time-to-Fix was not observed (p < 0.41). Postponement of sample staining has deleterious effects on the measurement of PMC via FCM. Delays in immunolabeling of fixed samples compromised measurement of PMC by 30% over the first 24 h. Staining/FCM should be completed within an hour of collection.

Cigarette Smoking and Incident Stroke in Blacks of the Jackson Heart Study

Background Blacks are disproportionately affected by stroke compared with whites; however, less is known about the relationship between stroke and cigarette smoking in blacks. Therefore, we evaluated the relationship between cigarette smoking and all incident stroke in the JHS (Jackson Heart Study). Methods and Results JHS participants without a history of stroke (n=4410) were classified by self-reported baseline smoking status into current, past (smoked at least 400 cigarettes/life), or never smokers at baseline (2000-2004). Current smokers were further classified by smoking intensity (number of cigarettes smoked per day [1-19 and ≥20]) and followed up for incident stroke (through 2015). Hazard ratios (HRs) for incident stroke for current and past smoking compared with never smoking were estimated with adjusted Cox proportional hazard regression models. After adjusting for cardiovascular risk factors, the risk for stroke in current smokers was significantly higher compared with never smokers (HR, 2.48; 95% CI, 1.60-3.83) but there was no significant difference between past smokers and never smokers (HR, 1.10; 95% CI, 0.74-1.64). There was a dose-dependent increased risk of stroke with smoking intensity (HR, 2.28 [95% CI, 1.38-3.86] and HR, 2.78 [95% CI, 1.47-5.28] for current smokers smoking 1-19 and ≥20 cigarettes/day, respectively). Conclusions In a large cohort of blacks, current cigarette smoking was associated with a dose-dependent higher risk of all stroke. In addition, past smokers did not have a significantly increased risk of all stroke compared with never smokers, which suggests that smoking cessation may have potential benefits in reducing the incidence of stroke in blacks.

Association Between E-Cigarette Use and Chronic Obstructive Pulmonary Disease by Smoking Status: Behavioral Risk Factor Surveillance System 2016 and 2017

INTRODUCTION

The association between e-cigarette use and chronic bronchitis, emphysema, and chronic obstructive pulmonary disease has not been studied thoroughly, particularly in populations defined by concomitant combustible smoking status.

METHODS

Using pooled 2016 and 2017 data from the Behavioral Risk Factor Surveillance System, investigators studied 705,159 participants with complete self-reported information on e-cigarette use, combustible cigarette use, key covariates, and chronic bronchitis, emphysema, or chronic obstructive pulmonary disease. Current e-cigarette use was the main exposure, with current use further classified as daily or occasional use. The main outcome was defined as reported ever having a diagnosis of chronic bronchitis, emphysema, or chronic obstructive pulmonary disease. For all the analyses, multivariable adjusted logistic regression was used, with the study population stratified by combustible cigarette use status (never, former, or current). All the analyses were conducted in 2019.

RESULTS

Of 705,159 participants, 25,175 (3.6%) were current e-cigarette users, 64,792 (9.2%) current combustible cigarette smokers, 207,905 (29.5%) former combustible cigarette smokers, 432,462 (61.3%) never combustible cigarette smokers, and 14,036 (2.0%) dual users of e-cigarettes and combustible cigarettes. A total of 53,702 (7.6%) participants self-reported chronic bronchitis, emphysema, or chronic obstructive pulmonary disease. Among never combustible cigarette smokers, current e-cigarette use was associated with 75% higher odds of chronic bronchitis, emphysema, or chronic obstructive pulmonary disease compared with never e-cigarette users (OR=1.75, 95% CI=1.25, 2.45), with daily users of e-cigarettes having the highest odds (OR=2.64, 95% CI=1.43, 4.89). Similar associations between e-cigarette use and chronic bronchitis, emphysema, or chronic obstructive pulmonary disease were noted among both former and current combustible cigarette smokers.

CONCLUSIONS

The results suggest possible e-cigarette-related pulmonary toxicity across all the categories of combustible cigarette smoking status, including those who had never smoked combustible cigarettes.

Ultrasound-induced molecular delivery to erythrocytes using a microfluidic system

Preservation of erythrocytes in a desiccated state for storage at ambient temperature could simplify blood transfusions in austere environments, such as rural clinics, far-forward military operations, and during space travel. Currently, storage of erythrocytes is limited by a short shelf-life of 42 days at 4 °C, and long-term preservation requires a complex process that involves the addition and removal of glycerol from erythrocytes before and after storage at -80 °C, respectively. Natural compounds, such as trehalose, can protect cells in a desiccated state if they are present at sufficient levels inside the cell, but mammalian cell membranes lack transporters for this compound. To facilitate compound loading across the plasma membrane via ultrasound and microbubbles (sonoporation), a polydimethylsiloxane-based microfluidic device was developed. Delivery of fluorescein into erythrocytes was tested at various conditions to assess the effects of parameters such as ultrasound pressure, ultrasound pulse interval, microbubble dose, and flow rate. Changes in ultrasound pressure and mean flow rate caused statistically significant increases in fluorescein delivery of up to 73 ± 37% (p < 0.05) and 44 ± 33% (p < 0.01), respectively, compared to control groups, but no statistically significant differences were detected with changes in ultrasound pulse intervals. Following freeze-drying and rehydration, recovery of viable erythrocytes increased by up to 128 ± 32% after ultrasound-mediated loading of trehalose compared to control groups (p < 0.05). These results suggest that ultrasound-mediated molecular delivery in microfluidic channels may be a viable approach to process erythrocytes for long-term storage in a desiccated state at ambient temperatures.

Association Between e-Cigarette Use and Depression in the Behavioral Risk Factor Surveillance System, 2016-2017

IMPORTANCE

The prevalence of the use of electronic cigarettes (e-cigarettes) in the United States has grown rapidly since their introduction to the market more than a decade ago. While several studies have demonstrated an association between combustible cigarette smoking and depression, the association between e-cigarette use and depression has not been thoroughly studied.

OBJECTIVE

To examine the association between e-cigarette use and depression in a nationally representative sample of the adult population in the United States.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional study of the Behavioral Risk Factor Surveillance System database, 2016 to 2017. The Behavioral Risk Factor Surveillance System is the largest national telephone-based survey of randomly sampled adults in the United States. A total of 892 394 participants with information on e-cigarette use and depression were included. Data analysis was conducted in May 2019.

EXPOSURES

Electronic cigarette use status defined by self-report as never, former, or current use.

MAIN OUTCOMES AND MEASURES

Self-reported history of a clinical diagnosis of depression.

RESULTS

Of the 892 394 participants (414 326 [29.0%] aged ≥60 years; 502 448 [51.3%] women), there were 28 736 (4.4%) current e-cigarette users, of whom 13 071 (62.1%) were aged between 18 and 39 years. Compared with never e-cigarette users, current e-cigarette users were more likely to be single, male, younger than 40 years, and current combustible cigarette smokers (single, 120 797 [24.3%] vs 10 517 [48.4%]; men, 318 970 [46.6%] vs 14 962 [60.1%]; aged 18-39 years, 129 085 [32.2%] vs 13 071 [62.1%]; current combustible cigarette use, 217 895 [7.9%] vs 8823 [51.8%]). In multivariable adjusted models, former e-cigarette users had 1.60-fold (95% CI, 1.54-1.67) higher odds of reporting a history of clinical diagnosis of depression than never users, whereas current e-cigarette users had 2.10 (95% CI, 1.98-2.23) times higher odds. Additionally, higher odds of reporting depression were observed with increased frequency of use among current e-cigarette users compared with never users (daily use: odds ratio, 2.39; 95% CI, 2.19-2.61; occasional use: odds ratio, 1.96; 95% CI, 1.82-2.10). Similar results were seen in subgroup analyses by sex, race/ethnicity, smoking status, and student status.

CONCLUSIONS AND RELEVANCE

This study found a significant cross-sectional association between e-cigarette use and depression, which highlights the need for prospective studies analyzing the longitudinal risk of depression with e-cigarette use. If confirmed by other study designs, the potential mental health consequences may have regulatory implications for novel tobacco products.

Clinical Practice Patterns in Temporary Mechanical Circulatory Support for Shock in the Critical Care Cardiology Trials Network (CCCTN) Registry

BACKGROUND

Temporary mechanical circulatory support (MCS) devices provide hemodynamic assistance for shock refractory to pharmacological treatment. Most registries have focused on single devices or specific etiologies of shock, limiting data regarding overall practice patterns with temporary MCS in cardiac intensive care units.

METHODS

The CCCTN (Critical Care Cardiology Trials Network) is a multicenter network of tertiary CICUs in North America. Between September 2017 and September 2018, each center (n=16) contributed a 2-month snapshot of consecutive medical CICU admissions.

RESULTS

Of the 270 admissions using temporary MCS, 33% had acute myocardial infarction-related cardiogenic shock (CS), 31% had CS not related to acute myocardial infarction, 11% had mixed shock, and 22% had an indication other than shock. Among all 585 admissions with CS or mixed shock, 34% used temporary MCS during the CICU stay with substantial variation between centers (range: 17%-50%). The most common temporary MCS devices were intraaortic balloon pumps (72%), Impella (17%), and veno-arterial extracorporeal membrane oxygenation (11%), although intraaortic balloon pump use also varied between centers (range: 40%-100%). Patients managed with intraaortic balloon pump versus other forms of MCS (advanced MCS) had lower Sequential Organ Failure Assessment scores and less severe metabolic derangements. Illness severity was similar at high- versus low-MCS utilizing centers and at centers with more advanced MCS use.

CONCLUSIONS

There is wide variation in the use of temporary MCS among patients with shock in tertiary CICUs. While hospital-level variation in temporary MCS device selection is not explained by differences in illness severity, patient-level variation appears to be related, at least in part, to illness severity.

The association between e-cigarette use and asthma among never combustible cigarette smokers: behavioral risk factor surveillance system (BRFSS) 2016 & 2017

BACKGROUND

E-cigarette use prevalence has grown rapidly in the US. Despite the popularity of these products, few acute exposure toxicity studies exist, and studies on long-term pulmonary health effects are limited. E-cigarette users who are never combustible cigarette smokers (sole users) constitute a unique group of young adults that may be at increased risk of bronchial hyperreactivity and development of asthma. Given the public health concern about the potential pulmonary health effects of sole e-cigarette use, we aimed to examine the association between e-cigarette use and asthma among never combustible cigarette smokers.

METHODS

We pooled 2016 and 2017 data of the Behavioral Risk Factor Surveillance System (BRFSS), a large, cross-sectional telephone survey of adults aged 18 years and older in the U.S. We included 402,822 participants without any history of combustible cigarette smoking (defined as lifetime smoking < 100 cigarettes) and with complete self-reported information on key variables. Current e-cigarette use, further classified as daily or occasional use, was the primary exposure. The main outcome, asthma, was defined as self-reported history of asthma. We assess the relationship of sole e-cigarette use with asthma using multivariable logistic regression adjusting for age, sex, race, income, level of education and body mass index.

RESULTS

Of 402,822 never combustible cigarette smokers, there were 3103 (0.8%) current e-cigarette users and 34,074 (8.5%) with asthma. The median age group of current e-cigarette users was 18-24 years. Current e-cigarette use was associated with 39% higher odds of self-reported asthma compared to never e-cigarette users (Odds Ratio [OR], 1.39; 95% confidence interval: 1.15, 1.68). There was a graded increased odds of having asthma with increase of e-cigarette use intensity. The odds ratio of self-reported asthma increased from 1.31 (95% confidence interval: 1.05, 1.62) in occasional users to 1.73 (95% confidence interval: 1.21, 2.48) in daily e-cigarette users, compared to never e-cigarette users.

CONCLUSION

Our findings from a large, nationally representative survey suggest increased odds of asthma among never combustible smoking e-cigarette users. This may have potential public health implications, providing a strong rationale to support future longitudinal studies of pulmonary health in young e-cigarette-using adults.

Assessment and Treatment of Patients With Type 2 Myocardial Infarction and Acute Nonischemic Myocardial Injury

Although coronary thrombus overlying a disrupted atherosclerotic plaque has long been considered the hallmark and the primary therapeutic target for acute myocardial infarction (MI), multiple other mechanisms are now known to cause or contribute to MI. It is further recognized that an MI is just one of many types of acute myocardial injury. The Fourth Universal Definition of Myocardial Infarction provides a taxonomy for acute myocardial injury, including 5 subtypes of MI and nonischemic myocardial injury. The diagnosis of MI is reserved for patients with myocardial ischemia as the cause of myocardial injury, whether attributable to acute atherothrombosis (type 1 MI) or supply/demand mismatch without acute atherothrombosis (type 2 MI). Myocardial injury in the absence of ischemia is categorized as acute or chronic nonischemic myocardial injury. However, optimal evaluation and treatment strategies for these etiologically distinct diagnoses have yet to be defined. Herein, we review the epidemiology, risk factor associations, and diagnostic tools that may assist in differentiating between nonischemic myocardial injury, type 1 MI, and type 2 MI. We identify limitations, review new research, and propose a framework for the diagnostic and therapeutic approach for patients who have suspected MI or other causes of myocardial injury.

Association Between E-Cigarette Use and Cardiovascular Disease Among Never and Current Combustible-Cigarette Smokers

BACKGROUND

The prevalence of e-cigarette use in the United States has increased rapidly. However, the association between e-cigarette use and cardiovascular disease remains virtually unknown. Therefore, we aimed to examine the association between e-cigarette use and cardiovascular disease among never and current combustible-cigarette smokers.

METHODS

We pooled 2016 and 2017 data from the Behavioral Risk Factor Surveillance System (BRFSS), a large, nationally representative, cross-sectional telephone survey. We included 449,092 participants with complete self-reported information on all key variables. The main exposure, e-cigarette use, was further divided into daily or occasional use, and stratified by combustible-cigarette use (never and current). Cardiovascular disease, the main outcome, was defined as a composite of self-reported coronary heart disease, myocardial infarction, or stroke.

RESULTS

Of 449,092 participants, there were 15,863 (3.5%) current e-cigarette users, 12,908 (2.9%) dual users of e-cigarettes + combustible cigarettes, and 44,852 (10.0%) with cardiovascular disease. We found no significant association between e-cigarette use and cardiovascular disease among never combustible-cigarette smokers. Compared with current combustible-cigarette smokers who never used e-cigarettes, dual use of e-cigarettes + combustible cigarettes was associated with 36% higher odds of cardiovascular disease (odds ratio 1.36; 95% confidence interval, 1.18-1.56); with consistent results in subgroup analyses of premature cardiovascular disease in women <65 years and men <55 years old.

CONCLUSION

Our results suggest significantly higher odds of cardiovascular disease among dual users of e-cigarettes + combustible cigarettes compared with smoking alone. These data, although preliminary, support the critical need to conduct longitudinal studies exploring cardiovascular disease risk associated with e-cigarette use, particularly among dual users.

Relation Between Cigarette Smoking and Heart Failure (from the Multiethnic Study of Atherosclerosis)

We studied the association between cigarette smoking and incident heart failure (HF) in a racially diverse US cohort. We included 6,792 participants from the Multi-Ethnic Study of Atherosclerosis with information on cigarette smoking at baseline, characterized by status, intensity, burden, and time since quitting. Adjudicated outcomes included total incident HF cases and HF stratified by ejection fraction (EF) into HF with reduced EF (HFrEF; EF ≤ 40%) and preserved EF (HFpEF; EF ≥ 50%). We used Cox proportional hazards models adjusted for traditional cardiovascular risk factors and accounted for competing risk of each HF type. Mean age was 62 ± 10 years; 53% were women, 61% were nonwhite, and 13% were current smokers. A total of 279 incident HF cases occurred over a median follow-up of 12.2 years. The incidence rates of HFrEF and HFpEF were 2.2 and 1.9 cases per 1000 person-years, respectively. Current smoking was associated with higher risk of HF compared with never smoking (hazard ratio [HR], 2.05; 95% confidence interval [CI], 1.36 to 3.09); this was similar for HFrEF (HR, 2.58; 95% CI, 1.27 to 5.25) and HFpEF (HR, 2.51; 95% CI, 1.15 to 5.49). Former smoking was not significantly associated with HF (HR, 1.17; 95% CI, 0.88 to 1.56). Smoking intensity, burden, and time since quitting did not provide additional information for HF risk after accounting for smoking status.