A Technology-Assisted Web Application for Consumer Access to a Nonprescription Statin Medication.

BACKGROUND: Although statins reduce adverse cardiovascular outcomes, less than one-half of eligible patients receive treatment. A nonprescription statin has the potential to improve access to statins. OBJECTIVES: This study sought to assess concordance between clinician and consumer assessment of eligibility for nonprescription statin treatment using a technology assisted self-selection Web application (Web App) and evaluate effect on low-density lipoprotein cholesterol (LDL-C) levels. METHODS: This study was a prospective actual use 6-month study to evaluate use of a Web App to qualify participants without a medical background for a moderate-intensity statin based on current guidelines. Participants entered demographic information, cholesterol values, blood pressure, and concomitant medications into the Web App, resulting in 3 possible outcomes: "do not use," "ask a doctor," and "OK to use." RESULTS: The study included 1,196 participants, with a median age of 63 years (Q1-Q3: 57-68 years); 39.6% were women, 79.3% were White, 11.7% were Black, and 4.1% had limited literacy. Mean LDL-C was 139.6 ± 28.3 mg/dL and the median calculated 10-year risk of atherosclerotic cardiovascular disease was 10.1% (Q1-Q3: 7.3%-14.0%). Initial Web App self-selection resulted in an outcome concordant with clinician assessment in 90.7% (95% CI: 88.9%-92.3%) of participants, and 98.1% (95% CI: 97.1%-98.8%) had a concordant final use outcome during treatment. Mean percent change in LDL-C was -35.5% (95% CI: -36.6% to -34.3%). Serious adverse events occurred in 27 (2.3%) participants, none related to the study drug. CONCLUSIONS: In this actual use study, a technology-assisted Web App allowed >90% of consumers to correctly self-select for statin use and achieve clinically important LDL-C reductions. (Technology-Assisted Cholesterol Trial in Consumers [TACTiC]; NCT04964544).

Impact of COVID-19 Pandemic on Sex and Racial Disparities in Chest Pain Presentation and Management Through the Emergency Department.

Background: Sex and racial disparities in the presentation and management of chest pain persist, however, the impact of coronavirus disease 2019 (COVID-19) on these disparities have not been studied. We sought to determine whether the COVID-19 pandemic contributed to pre-existing sex and racial disparities in the presentation, management, and outcomes of patients presenting to the emergency department (ED) with chest pain. Methods: We conducted an observational cohort study with retrospective data collection of patients between January 1, 2016, and May 1, 2022. This was a single study conducted at a quaternary academic medical center of all patients who presented to the ED with a complaint of chest pain or chest pain equivalent symptoms. Patient were further segregated into different groups based on sex (male, female), race, ethnicity (Asian, Black, Hispanic, White, and other), and age (18 - 40, 41 - 65, > 65). We compared diagnostic evaluations, treatment decisions, and outcomes during prespecified time points before, during, and after the COVID-19 pandemic. Results: This study included 95,764 chest pain encounters. Total chest pain presentations to the ED fell about 38% during the early pandemic months. Females presented significantly less than males during initial COVID-19 (48% vs. 52%, P < 0.001) and Asian females were least likely to present. There was an increase in the total number of troponins and echocardiograms ordered during peak COVID-19 across both sexes, but females were still less likely to have these tests ordered across all timepoints. The number of coronary angiograms did not increase during peak COVID-19, and females were less likely to undergo coronary angiogram during all timepoints. Finally, females with chest pain were less likely to be diagnosed with acute myocardial infarction (AMI) during all timepoints, while in-hospital deaths were similar between males and females during all timepoints. Conclusions: During COVID-19, females, especially Asian females, were less likely to present to the ED for chest pain. Non-White patients were less likely to present to the ED compared to White patients prior to and during the pandemic. Disparities in management and outcomes of chest pain encounters remained similar to pre-COVID-19, with females receiving less cardiac workup and AMI diagnoses than males, but in-hospital mortality remaining similar between groups and timepoints.

Associations Between Visceral Fat, Abdominal Muscle, and Coronary Artery Calcification: A Cross-Sectional Analysis of the Multi-Ethnic Study of Atherosclerosis.

The associations of body composition components, including muscle and adipose tissue, and markers of subclinical coronary artery disease are unclear. We examined the relation between abdominal computed tomography (CT)-derived measures of the area and density of fat and muscle with coronary artery calcification (CAC), using data from the Multi-Ethnic Study of Atherosclerosis (MESA). A total of 1,974 randomly selected MESA participants free of coronary heart disease underwent abdominal CT scans at examinations 2 or 3, with the resulting images interrogated for abdominal body composition. Using 6 cross-sectional slices spanning L2 to L5, the Medical Imaging Processing Analysis and Visualization software was used to determine abdominal muscle and fat composition using appropriate Hounsfield units ranges. CT chest scans were used to obtain CAC scores, calculated using the Agatston method and spatially weighted calcium score. Multivariable linear and logistic regression analyses were performed to assess the relation between abdominal visceral fat and muscle area and density to prevalent CAC. A total of 1,089 participants had a CAC >0, with an average CAC score of 310. In the fully adjusted model, for every 10-cm2 increase in visceral fat area, the likelihood of having a CAC greater than 0 increased by 0.60% (p <0.001). In the minimally adjusted model, abdominal muscle area was significantly associated with CAC >0, which became nonsignificant in the fully adjusted model. For the density of visceral fat, every 1-Hounsfield unit increase (less lipid-dense fat tissue), the likelihood of having a CAC score >0 decreased by 0.29% (p <0.05). No significant relation was observed between density of abdominal muscle and CAC >0. A greater area and higher lipid density of abdominal visceral fat were associated with an increased likelihood of having CAC, whereas there was no significant relation between abdominal muscle area or density and CAC. The quantity and the quality of fat have associations, with an important marker of subclinical atherosclerosis, CAC, and their significance with respect to cardiovascular outcomes, require further evaluation.

Peripheral Blood Mononuclear Cell Gene Expression Associated with Pulmonary Microvascular Perfusion: The Multi-Ethnic Study of Atherosclerosis Chronic Obstructive Pulmonary Disease Study.

Rationale Chronic obstructive pulmonary disease (COPD) and emphysema are associated with endothelial damage and altered pulmonary microvascular perfusion. Molecular mechanisms underlying these changes are poorly understood in patients due, in part, to the inaccessibility of the pulmonary vasculature. Peripheral blood mononuclear cells (PBMC) interact with the pulmonary endothelium. Objective To test the association between gene expression in PBMCs and pulmonary microvascular perfusion in COPD. Methods The Multi-Ethnic Study of Atherosclerosis (MESA) COPD Study recruited two independent samples of COPD cases and controls with 10 or more pack-years. In both samples, pulmonary microvascular blood flow, pulmonary microvascular blood volume (PMBV), and mean transit time were assessed on contrast-enhanced MRI, and PBMC gene expression was assessed by microarray. Additional replication was performed in a third sample with PMBV measures on contrast-enhanced, dual-energy CT. Differential expression analyses were adjusted for age, gender, race-ethnicity, educational attainment, height, weight, smoking status, and pack-years. Results The 79 participants in the discovery sample had mean age of 69±6 years, 44% were female, 25% were non-white, 34% were current smokers and 66% had COPD. There were large PBMC gene expression signatures associated with pulmonary microvascular perfusion traits, with several replicated in the replication sets with MRI (n=47) or dual-energy CT scan (n=157) measures. Many of the identified genes are involved in inflammatory processes, including NF-κB and chemokine signaling pathways. Conclusions PBMC gene expression in NF-κB, inflammatory and chemokine signaling pathways was associated pulmonary microvascular perfusion in COPD, potentially offering new targetable candidates for novel therapies.

Airway tree caliber heterogeneity and airflow obstruction among older adults.

Smaller mean airway tree caliber is associated with airflow obstruction and chronic obstructive pulmonary disease (COPD). We investigated whether airway tree caliber heterogeneity was associated with airflow obstruction and COPD. Two community-based cohorts (MESA Lung, CanCOLD) and a longitudinal case-control study of COPD (SPIROMICS) performed spirometry and computed tomography measurements of airway lumen diameters at standard anatomical locations (trachea-to-subsegments) and total lung volume. Percent-predicted airway lumen diameters were calculated using sex-specific reference equations accounting for age, height, and lung volume. The association of airway tree caliber heterogeneity, quantified as the standard deviation (SD) of percent-predicted airway lumen diameters, with baseline forced expired volume in 1-second (FEV1), FEV1/forced vital capacity (FEV1/FVC) and COPD, as well as longitudinal spirometry, were assessed using regression models adjusted for age, sex, height, race-ethnicity, and mean airway tree caliber. Among 2,505 MESA Lung participants (means ± SD age: 69 ± 9 yr; 53% female, mean airway tree caliber: 99 ± 10% predicted, airway tree caliber heterogeneity: 14 ± 5%; median follow-up: 6.1 yr), participants in the highest quartile of airway tree caliber heterogeneity exhibited lower FEV1 (adjusted mean difference: -125 mL, 95%CI: -171,-79), lower FEV1/FVC (adjusted mean difference: -0.01, 95%CI: -0.02,-0.01), and higher odds of COPD (adjusted odds ratio: 1.42, 95%CI: 1.01-2.02) when compared with the lowest quartile, whereas longitudinal changes in FEV1 and FEV1/FVC did not differ significantly. Observations in CanCOLD and SPIROMICS were consistent. Among older adults, airway tree caliber heterogeneity was associated with airflow obstruction and COPD at baseline but was not associated with longitudinal changes in spirometry.NEW & NOTEWORTHY In this study, by leveraging two community-based samples and a case-control study of heavy smokers, we show that among older adults, airway tree caliber heterogeneity quantified by CT is associated with airflow obstruction and COPD independent of age, sex, height, race-ethnicity, and dysanapsis. These observations suggest that airway tree caliber heterogeneity is a structural trait associated with low baseline lung function and normal decline trajectory that is relevant to COPD.

Adipokines and adiposity among postmenopausal women of the Multi-Ethnic Study of Atherosclerosis.

OBJECTIVE: We investigated whether the associations of serum adiponectin, leptin, and resistin with adiposity differ with menopausal age. METHODS: In this cross-sectional study, we included 751 postmenopausal women from the Multi-Ethnic Study of Atherosclerosis (MESA) who reported their menopausal age (<45, 45-49, 50-54 and ≥55 y) and had anthropometrics, serum adipokines, and abdominal computed tomography measures of visceral and subcutaneous adipose tissue (VAT and SAT) obtained at MESA exam 2 or 3. Linear regression models were used for analysis. RESULTS: The mean ± SD age was 65.1 ± 9.0 years for all participants. The median (interquartile range) values for serum adiponectin, leptin and resistin, VAT, and SAT were 21.9 (14.8-31.7) ng/L, 24.3 (12.5-42.4) pg/L, 15.3 (11.8-19.5) pg/L, 183.9 (130.8-251.1) cm2, and 103.7 (65.6-151.5) cm2, respectively. The mean ± SD values for body mass index, waist circumference, and waist-to-hip ratio were 28.3 ± 5.81 kg/m2, 96.6 ± 15.9 cm, and 0.91 ± 0.078, respectively. Adiponectin was inversely associated with all adiposity measures, with similar patterns across menopausal age categories. Leptin was positively associated with all adiposity measures, and the strength of associations varied across menopausal age categories for body mass index, waist circumference, and SAT (Pinteraction ≤ 0.01 for all). The associations of resistin with adiposity measures were mostly nonsignificant except in the 45- to 49-year menopausal age category. CONCLUSIONS: Menopausal age category had no influence on the association of serum adiponectin with adiposity. The association of serum leptin and resistin differed according to menopausal age category for generalized adiposity but was inconsistent for measures of abdominal adiposity.

National Trends in Racial and Ethnic Disparities in Use of Recommended Therapies in Adults with Atherosclerotic Cardiovascular Disease, 1999-2020.

Importance: Despite efforts to improve the quality of care for patients with atherosclerotic cardiovascular disease (ASCVD), it is unclear whether the US has made progress in reducing racial and ethnic differences in utilization of guideline-recommended therapies for secondary prevention. Objective: To evaluate 21-year trends in racial and ethnic differences in utilization of guideline-recommended pharmacological medications and lifestyle modifications among US adults with ASCVD. Design, Setting, and Participants: This cross-sectional study includes data from the National Health and Nutrition Examination Survey between 1999 and 2020. Eligible participants were adults aged 18 years or older with a history of ASCVD. Data were analyzed between March 2022 and May 2023. Exposure: Self-reported race and ethnicity. Main Outcome and Measures: Rates and racial and ethnic differences in the use of guideline-recommended pharmacological medications and lifestyle modifications. Results: The study included 5218 adults with a history of ASCVD (mean [SD] age, 65.5 [13.2] years, 2148 women [weighted average, 44.2%]), among whom 1170 (11.6%) were Black, 930 (7.7%) were Hispanic or Latino, and 3118 (80.7%) were White in the weighted sample. Between 1999 and 2020, there was a significant increase in total cholesterol control and statin use in all racial and ethnic subgroups, and in angiotensin-converting enzyme inhibitor (ACEI) and angiotensin receptor blocker (ARB) utilization in non-Hispanic White individuals and Hispanic and Latino individuals (Hispanic and Latino individuals: 17.12 percentage points; 95% CI, 0.37-37.88 percentage points; P = .046; non-Hispanic White individuals: 12.14 percentage points; 95% CI, 6.08-18.20 percentage points; P < .001), as well as smoking cessation within the Hispanic and Latino population (-27.13 percentage points; 95% CI, -43.14 to -11.12 percentage points; P = .002). During the same period, the difference in smoking cessation between Hispanic and Latino individuals and White individuals was reduced (-24.85 percentage points; 95% CI, -38.19 to -11.51 percentage points; P < .001), but racial and ethnic differences for other metrics did not change significantly. Notably, substantial gaps persisted between current care and optimal care throughout the 2 decades of data analyzed. In the period of 2017 to 2020, optimal regimens were observed in 47.4% (95% CI, 39.3%-55.4%), 48.7% (95% CI, 36.7%-60.6%), and 53.0% (95% CI, 45.6%-60.4%) of Black, Hispanic and Latino, and White individuals, respectively. Conclusions and Relevance: In this cross-sectional study of US adults with ASCVD, significant disparities persisted between current care and optimal care, surpassing any differences observed among demographic groups. These findings highlight the critical need for sustained efforts to bridge these gaps and achieve better outcomes for all patients, regardless of their racial and ethnic backgrounds.

Urinary cortisol and cardiovascular events in women vs. men: The multi-ethnic study of atherosclerosis.

Research suggests that women experience greater cardiovascular ischemic effects from stress than men. Visceral adiposity is an endocrine tissue that differs by sex and interacts with stress hormones. We hypothesized that urinary cortisol would be associated with increased cardiovascular events and change in coronary artery calcium score (CAC) in women, and these relationships would vary by central obesity. In the Multi-Ethnic Study of Atherosclerosis Stress Ancillary study, cortisol was quantified by 12-h overnight urine collection. Central obesity was estimated by waist-hip ratio (WHR). Multivariable Cox models estimated the relationship between cortisol and cardiovascular events and assessed for moderation by WHR. The relationship between cortisol and change in CAC Agatston score was assessed by Tobit regression models. 918 patients were analyzed with median follow up of 11 years. There was no association between urinary cortisol and cardiovascular events in the cohort. However, in individuals with below median WHR, higher urinary cortisol levels (upper tertile) were associated with higher cardiovascular event rates in the full cohort, women, and men, but not in groups with above median WHR. There was significant moderation by WHR in women, but not men, whereby the association between elevated cortisol and increased cardiovascular events diminished as WHR increased. Urinary cortisol was associated with increased change in CAC in women (P = 0.003) but not men, without moderation by WHR. Our study highlights associations between cortisol and subclinical atherosclerosis in women, and moderation of the relationship between cortisol and cardiovascular events by central obesity in both genders.

Coronary Artery Calcium and Cognitive Decline in the Diabetes Prevention Program Outcomes Study.

Background Our aim was to investigate the association of coronary artery calcium (CAC) with cognitive function in adults with impaired glucose tolerance or type 2 diabetes. Methods and Results The Diabetes Prevention Program was a randomized controlled trial comparing an intensive lifestyle intervention, metformin, or placebo for prevention of type 2 diabetes among patients with prediabetes. After 3 years, intensive lifestyle intervention and placebo were stopped, the metformin arm was unmasked, and participants continued in the DPPOS (Diabetes Prevention Program Outcomes Study). Approximately 14 years after randomization (Y14), CAC (Agatston score) was assessed with computed tomography, and cognitive performance was assessed with the Spanish English Verbal Learning Test (SEVLT) and Digit Symbol Substitution Test. SEVLT and Digit Symbol Substitution Test were reassessed 5 years later (Y19) along with the Modified Mini-Mental State Exam. We examined cross-sectional and longitudinal associations between CAC and cognition among 1931 participants using linear and logistic regression. In unadjusted analyses, compared with no calcification, CAC score >300 was associated with decreased performance on all cognitive tests at Y14 in both sexes. Additionally, CAC >300 was associated with a greater 5-year decline in SEVLT Immediate Recall in both sexes and SEVLT Delayed Recall in women. After adjustment for demographic, genetic, metabolic, vascular, and behavioral covariates, CAC score >300 remained associated with greater decline in only SEVLT Delayed Recall in women. Conclusions In women with prediabetes or diabetes, CAC >300, compared with no calcification, was independently associated with greater decline in verbal memory. Registration information clinicaltrials.gov. Identifier: NCT00038727.

Endogenous Sex Hormone Levels and Myocardial Fibrosis in Men and Postmenopausal Women.

BACKGROUND: Sex hormone (SH) imbalances have been linked to a higher risk of heart failure in both sexes. However, mechanisms that underlie this relationship remain unclear. We examined the association of baseline SH with interstitial and replacement myocardial fibrosis in the MESA (Multi-Ethnic Study of Atherosclerosis) using cardiac magnetic resonance (CMR) T1 mapping and late gadolinium enhancement (LGE). OBJECTIVES: The purpose of this study was to assess the link between baseline sex hormone levels and myocardial fibrosis in the MESA cohort using CMR. METHODS: A total of 2,324 participants (men and postmenopausal women [PMW]) were included in the MESA with SH measured at baseline and had underwent CMR 10 years later. All analyses were stratified by sex and age. Regression models were constructed to assess the associations of baseline SH with extracellular volume (ECV)% and native T1 time and with LGE. Higher native T1 time and ECV% are interpreted as evidence of increasing interstitial myocardial fibrosis (IMF). Given the limited number of myocardial scars present in PMW, analysis of LGE was limited to men. RESULTS: Among older men (age ≥65 years), a 1-SD increment higher free testosterone was significantly associated with 2.45% lower ECV% and 21.5% lower native T1 time, while a 1-SD increment higher bioavailable testosterone was associated with 12.5% lower native T1 time. A 1-SD increment greater sex hormone-binding globulin level was associated with 1% higher ECV%. Among PMW of 55 to 64 years, a 1-SD increment higher total testosterone was associated with 9.5% lower native T1 time. Higher levels of estradiol in older men were independently associated with higher odds of having a myocardial scar (OR: 4.10; 95% CI: 1.35-12.40; P = 0.01). CONCLUSIONS: Among older men, SH imbalances at initial evaluation were independently associated with CMR defined IMF and replacement fibrosis, respectively; while increasing total testosterone in middle-aged PMW was associated with lesser marker of IMF. (JACC Adv 2023;2:100320) Published by Elsevier on behalf of the American College of Cardiology Foundation.

Pulmonary emphysema subtypes defined by unsupervised machine learning on CT scans.

BACKGROUND: Treatment and preventative advances for chronic obstructive pulmonary disease (COPD) have been slow due, in part, to limited subphenotypes. We tested if unsupervised machine learning on CT images would discover CT emphysema subtypes with distinct characteristics, prognoses and genetic associations. METHODS: New CT emphysema subtypes were identified by unsupervised machine learning on only the texture and location of emphysematous regions on CT scans from 2853 participants in the Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS), a COPD case-control study, followed by data reduction. Subtypes were compared with symptoms and physiology among 2949 participants in the population-based Multi-Ethnic Study of Atherosclerosis (MESA) Lung Study and with prognosis among 6658 MESA participants. Associations with genome-wide single-nucleotide-polymorphisms were examined. RESULTS: The algorithm discovered six reproducible (interlearner intraclass correlation coefficient, 0.91-1.00) CT emphysema subtypes. The most common subtype in SPIROMICS, the combined bronchitis-apical subtype, was associated with chronic bronchitis, accelerated lung function decline, hospitalisations, deaths, incident airflow limitation and a gene variant near DRD1, which is implicated in mucin hypersecretion (p=1.1 ×10-8). The second, the diffuse subtype was associated with lower weight, respiratory hospitalisations and deaths, and incident airflow limitation. The third was associated with age only. The fourth and fifth visually resembled combined pulmonary fibrosis emphysema and had distinct symptoms, physiology, prognosis and genetic associations. The sixth visually resembled vanishing lung syndrome. CONCLUSION: Large-scale unsupervised machine learning on CT scans defined six reproducible, familiar CT emphysema subtypes that suggest paths to specific diagnosis and personalised therapies in COPD and pre-COPD.

Excess Mortality and Years of Potential Life Lost Among the Black Population in the US, 1999-2020.

Importance: Amid efforts in the US to promote health equity, there is a need to assess recent progress in reducing excess deaths and years of potential life lost among the Black population compared with the White population. Objective: To evaluate trends in excess mortality and years of potential life lost among the Black population compared with the White population. Design, setting, and participants: Serial cross-sectional study using US national data from the Centers for Disease Control and Prevention from 1999 through 2020. We included data from non-Hispanic White and non-Hispanic Black populations across all age groups. Exposures: Race as documented in the death certificates. Main outcomes and measures: Excess age-adjusted all-cause mortality, cause-specific mortality, age-specific mortality, and years of potential life lost rates (per 100 000 individuals) among the Black population compared with the White population. Results: From 1999 to 2011, the age-adjusted excess mortality rate declined from 404 to 211 excess deaths per 100 000 individuals among Black males (P for trend <.001). However, the rate plateaued from 2011 through 2019 (P for trend = .98) and increased in 2020 to 395-rates not seen since 2000. Among Black females, the rate declined from 224 excess deaths per 100 000 individuals in 1999 to 87 in 2015 (P for trend <.001). There was no significant change between 2016 and 2019 (P for trend = .71) and in 2020 rates increased to 192-levels not seen since 2005. The trends in rates of excess years of potential life lost followed a similar pattern. From 1999 to 2020, the disproportionately higher mortality rates in Black males and females resulted in 997 623 and 628 464 excess deaths, respectively, representing a loss of more than 80 million years of life. Heart disease had the highest excess mortality rates, and the excess years of potential life lost rates were largest among infants and middle-aged adults. Conclusions and relevance: Over a recent 22-year period, the Black population in the US experienced more than 1.63 million excess deaths and more than 80 million excess years of life lost when compared with the White population. After a period of progress in reducing disparities, improvements stalled, and differences between the Black population and the White population worsened in 2020.

Assessing and Addressing Social Determinants of Cardiovascular Health: JACC State-of-the-Art Review.

Social determinants of health (SDOH) are the social conditions in which people are born, live, and work. SDOH offers a more inclusive view of how environment, geographic location, neighborhoods, access to health care, nutrition, socioeconomics, and so on are critical in cardiovascular morbidity and mortality. SDOH will continue to increase in relevance and integration of patient management, thus, applying the information herein to clinical and health systems will become increasingly commonplace. This state-of-the-art review covers the 5 domains of SDOH, including economic stability, education, health care access and quality, social and community context, and neighborhood and built environment. Recognizing and addressing SDOH is an important step toward achieving equity in cardiovascular care. We discuss each SDOH within the context of cardiovascular disease, how they can be assessed by clinicians and within health care systems, and key strategies for clinicians and health care systems to address these SDOH. Summaries of these tools and key strategies are provided.

Locking the Revolving Door: Racial Disparities in Cardiovascular Disease.

Racial disparities in cardiovascular disease are unjust, systematic, and preventable. Social determinants are a primary cause of health disparities, and these include factors such as structural and overt racism. Despite a number of efforts implemented over the past several decades, disparities in cardiovascular disease care and outcomes persist, pervading more the outpatient rather than the inpatient setting, thus putting racial and ethnic minority groups at risk for hospital readmissions. In this article, we discuss differences in care and outcomes of racial and ethnic minority groups in both of these settings through a review of registries. Furthermore, we explore potential factors that connote a revolving door phenomenon for those whose adverse outpatient environment puts them at risk for hospital readmissions. Additionally, we review promising strategies, as well as actionable items at the policy, clinical, and educational levels aimed at locking this revolving door.

Association Between Measures of Body Composition and Coronary Calcium: Findings From the Multi-Ethnic Study of Atherosclerosis.

Background Obesity, as measured by body mass index, is widely recognized as a risk factor for the development of cardiovascular disease. However, the role of body composition components such as fat and lean mass is not well studied. Methods and Results A total of 3129 patients who underwent computed tomography scans for quantification of coronary artery calcification and had bioelectrical impedance analysis of body composition (fat mass and fat-free mass) during exam 5 of MESA (Multi-Ethnic Study of Atherosclerosis) were included in this cross-sectional analysis. Multivariable adjusted linear regression analysis was performed to assess the relationship between both fat mass and fat-free mass to prevalent coronary artery calcification, a marker of subclinical coronary artery disease quantified by both the coronary artery calcification (CAC) Agatston score and the spatially weighted calcium score. CAC and spatially weighted calcium score were natural log-transformed for analysis as continuous variables. Fat-free mass, but not fat mass, was independently associated with CAC. There was a 7.6% prevalence risk difference for CAC>0 per 10 kg. Fat-free mass was also significantly associated with natural log of CAC (coefficient=0.272, P<0.001). Both fat-free mass and fat mass were positively associated with natural log of spatially weighted calcium score, with risk difference coefficients of 0.729 and 0.359, respectively (P<0.001). Conclusions In this cross-sectional study, higher lean mass by bioelectrical impedance analysis and, to a lesser extent, higher fat mass by bioelectrical impedance analysis were significantly associated with higher coronary calcium, a marker of subclinical cardiovascular disease. Further exploration of the relationship between components of body composition and the development of cardiovascular disease is warranted.

Heterogeneity in the Association Between the Presence of Coronary Artery Calcium and Cardiovascular Events: A Machine-Learning Approach in the MESA Study.

BACKGROUND: Coronary artery calcium (CAC) has been widely recognized as an important predictor of cardiovascular disease (CVD). Given the finite resources, it is important to identify individuals who would receive the most benefit from detecting positive CAC by screening. However, the evidence is limited as to whether the burden of positive CAC on CVD differs by multidimensional individual characteristics. We sought to investigate the heterogeneity in the association between positive CAC and incident CVD. METHODS: This cohort study included adults from MESA (Multi-Ethnic Study of Atherosclerosis) ages ≥45 years and free of cardiovascular disease. After propensity score matching in a 1:1 ratio, we applied a machine learning causal forest model to (1) evaluate the heterogeneity in the association between positive CAC and incident CVD, and (2) predict the increase in CVD risk at 10-years when CAC>0 (versus CAC=0) at the individual level. We then compared the estimated increase in CVD risk when CAC>0 to the absolute 10-year atherosclerotic CVD (ASCVD) risk calculated by the 2013 American College of Cardiology/American Heart Association pooled cohort equations. RESULTS: Across 3328 adults in our propensity score-matched analysis, our causal forest model showed the heterogeneity in the association between CAC>0 and incident CVD. We found a dose-response relationship of the estimated increase in CVD risk when CAC>0 with higher 10-year ASCVD risk. Almost all individuals (2293 of 2428 [94.4%]) with borderline risk of ASCVD or higher showed ≥2.5% increase in CVD risk when CAC>0. Even among 900 adults with low ASCVD risk, 689 (69.2%) showed ≥2.5% increase in CVD risk when CAC>0; these individuals were more likely to be male, Hispanic, and have unfavorable CVD risk factors than others. CONCLUSIONS: The expected increases in CVD risk when CAC>0 were heterogeneous across individuals. Moreover, nearly 70% of people with low ASCVD risk showed a large increase in CVD risk when CAC>0, highlighting the need for CAC screening among such low-risk individuals. Future studies are needed to assess whether targeting individuals for CAC measurements based on not only the absolute ASCVD risk but also the expected increase in CVD risk when CAC>0 improves cardiovascular outcomes.