Coronary Artery Calcium for Risk Stratification Among Persons With Very High HDL Cholesterol.

Background: Compared to normal high-density lipoprotein (HDL) cholesterol values, very high HDL cholesterol is associated with a higher incidence of mortality and atherosclerotic cardiovascular disease (ASCVD). As such, clinical risk stratification among persons with very high HDL cholesterol is challenging. Objectives: Among persons with very high HDL cholesterol, the purpose was to determine the prevalence of coronary artery calcium (CAC) and compare the association between traditional risk factors vs CAC for all-cause mortality and ASCVD. Methods: The primary analysis was completed among 446 participants from the Cedars-Sinai Medical Center of the CAC Consortium with very high HDL cholesterol (≥77 mg/dL in men, ≥97 mg/dL in women). Cox proportional hazards regression assessed the association of CAC and traditional risk factors with all-cause mortality during a median follow-up of 10.7 years. Replication and validation analyses were performed for all-cause mortality among 119 participants from the Multi-Ethnic Study of Atherosclerosis (MESA) with very high HDL cholesterol, who also had information on incident ASCVD. Results: The mean age was 57.9 years old, 49% were women, and the median HDL cholesterol was 98 mg/dL. One-half of participants (50%) had prevalent CAC, in whom the median CAC score was 118. Prevalent CAC conferred a 3.6-fold higher risk of all-cause mortality (HR: 3.64; 95% CI: 1.21-11.01), which appeared to be a more robust predictor than individual traditional risk factors beyond age. In the validation sample, prevalent CAC but not individual traditional risk factors were associated with all-cause mortality (HR: 2.39; 95% CI: 1.07-5.34) and a 4.0-fold higher risk of ASCVD (HR: 4.06; 95% CI: 1.11-14.84). Conclusions: Measurement of CAC may facilitate clinical risk assessment among individuals with very high HDL cholesterol.

Left Main Coronary Artery Calcium and Diabetes Confer Very-High-Risk Equivalence in Coronary Artery Calcium >1,000.

BACKGROUND: Although a coronary artery calcium (CAC) of ≥1,000 is a subclinical atherosclerosis threshold to consider combination lipid-lowering therapy, differentiating very high from high atherosclerotic cardiovascular disease (ASCVD) risk in this patient population is not well-defined. OBJECTIVES: Among persons with a CAC of ≥1,000, the authors sought to identify risk factors equating with very high-risk ASCVD mortality rates. METHODS: The authors studied 2,246 asymptomatic patients with a CAC of ≥1,000 from the CAC Consortium without a prior ASCVD event. Cox proportional hazards regression modelling was performed for ASCVD mortality during a median follow-up of 11.3 years. Crude ASCVD mortality rates were compared with those reported for secondary prevention trial patients classified as very high risk, defined by ≥2 major ASCVD events or 1 major event and ≥2 high-risk conditions (1.4 per 100 person-years). RESULTS: The mean age was 66.6 years, 14% were female, and 10% were non-White. The median CAC score was 1,592 and 6% had severe left main (LM) CAC (vessel-specific CAC ≥300). Diabetes (HR: 2.04 [95% CI: 1.47-2.83]) and severe LM CAC (HR: 2.32 [95% CI: 1.51-3.55]) were associated with ASCVD mortality. The ASCVD mortality per 100 person-years for all patients was 0.8 (95% CI: 0.7-0.9), although higher rates were observed for diabetes (1.4 [95% CI: 0.8-1.9]), severe LM CAC (1.3 [95% CI: 0.6-2.0]), and both diabetes and severe LM CAC (7.1 [95% CI: 3.4-10.8]). CONCLUSIONS: Among asymptomatic patients with a CAC of ≥1,000 without a prior index event, diabetes, and severe LM CAC define very high risk ASCVD, identifying individuals who may benefit from more intensive prevention therapies across several domains, including low-density lipoprotein-cholesterol lowering.

Clinical characteristics and statin eligibility of patients under 50 with ST-elevation myocardial infarction.

AIMS: This study seeks to understand the clinical characteristics, risk factors, and statin eligibility of younger adults who present with STEMI. METHODS: We performed a retrospective analysis of a prospective cohort of STEMI patients <50 years. Baseline characteristics, medical history, prior medications, drug use, lipid profiles, cardiovascular risk factors were examined. Ten-year ASCVD risk was calculated utilizing the Pooled Cohort Equations. Statin eligibility was determined according to the 2019 American College of Cardiology (ACC)/American Heart Association (AHA) and the 2022 US Preventive Services Task Force (USPSTF) guidelines. RESULTS: Six hundred and thirty-five individuals were included, the majority were men (82.4%) and white (89%), with a median age was 46.9 [42.0-48.0]. The most prevalent risk factors were current smoking (59%), hyperlipidemia (44%), and hypertension (37%). Drug use was rare (8.3%). Preventative medication use was low, aspirin was the most common (14%), followed by ACE inhibitors/ARBs (12%), statins (11%), and beta-blockers (9.1%). Mean HDL-C was low at 36.4 ± 12.0 mg/dL, while mean LDL was unremarkable at 112.4 ± 37.9 mg/dL. According to the 2019 ACC/AHA guidelines, 45.5% were classified as statin recommended, 8.7% were classified as statin considered, and 45.8% were classified as statin not recommended. According to the 2022 USPSTF guidelines, 29% were classified as statin recommended, 12.4% were classified as statin considered, and 58.6% were classified as statin not recommended. CONCLUSIONS: Younger adults with STEMI exhibit high rates of tobacco use and low rates of preventative medications use. Approximately half of the cohort did not meet criteria for statin initiation.

Thoracic Aortic Calcium Density and Area in Long-Term Atherosclerotic Cardiovascular Disease Risk Among Men Versus Women.

BACKGROUND: The development of thoracic aortic calcium (TAC) temporally precedes coronary artery calcium more often in women versus men. Whether TAC density and area confer sex-specific differences in atherosclerotic cardiovascular disease (ASCVD) risk is unknown. METHODS: We studied 5317 primary prevention patients who underwent coronary artery calcium scoring on noncontrast cardiac gated computed tomography with TAC >0. The Agatston TAC score (Agatston units), density (Hounsfield units), and area (mm2) were compared between men and women. Cox proportional hazards regression calculated adjusted hazard ratios for TAC density-area groups with ASCVD mortality, adjusting for traditional risk factors, coronary artery calcium, and TAC. Multinomial logistic regression calculated adjusted odds ratios for the association between traditional risk factors and TAC density-area groups. RESULTS: The mean age was 60.7 years, 38% were women, and 163 ASCVD deaths occurred over a median of 11.7-year follow-up. Women had higher median TAC scores (97 versus 84 Agatston units; P=0.004), density (223 versus 210 Hounsfield units; P<0.001), and area (37 versus 32 mm2; P=0.006) compared with men. There was a stepwise higher incidence of ASCVD deaths across increasing TAC density-area groups in men though women with low TAC density relative to TAC area (3.6 per 1000 person-years) had survival probability commensurate with the high-density-high-area group (4.8 per 1000 person-years). Compared with low TAC density-area, low TAC density/high TAC area conferred a 3.75-fold higher risk of ASCVD mortality in women (adjusted hazard ratio, 3.75 [95% CI, 1.13-12.44]) but not in men (adjusted hazard ratio, 1.16 [95% CI, 0.48-2.84]). Risk factors most strongly associated with low TAC density/high TAC area differed in women (diabetes: adjusted odds ratio, 2.61 [95% CI, 1.34-5.07]) versus men (hypertension: adjusted odds ratio, 1.45 [95% CI, 1.11-1.90]). CONCLUSIONS: TAC density-area phenotypes do not consistently associate with ASCVD mortality though low TAC density relative to area may be a marker of increased ASCVD risk in women.

Cardiovascular risk stratification among individuals with obesity: The Coronary Artery Calcium Consortium.

OBJECTIVE: The effectiveness of coronary artery calcification (CAC) for risk stratification in obesity, in which imaging is often limited because of a reduced signal to noise ratio, has not been well studied. METHODS: Data from 9334 participants (mean age: 53.3 ± 9.7 years; 67.9% men) with BMI ≥ 30 kg/m2 from the CAC Consortium, a retrospectively assembled cohort of individuals with no prior cardiovascular diseases (CVD), were used. The predictive value of CAC for all-cause and cause-specific mortality was evaluated using multivariable-adjusted Cox proportional hazards and competing-risks regression. RESULTS: Mean BMI was 34.5 (SD 4.4) kg/m2 (22.7% Class II and 10.8% Class III obesity), and 5461 (58.5%) had CAC. Compared with CAC = 0, those with CAC = 1-99, 100-299, and ≥300 Agatston units had higher rates (per 1000 person-years) of all-cause (1.97 vs. 3.5 vs. 5.2 vs. 11.3), CVD (0.4 vs. 1.1 vs. 1.5 vs. 4.2), and coronary heart disease (CHD) mortality (0.2 vs. 0.6 vs. 0.6 vs. 2.5), respectively, after mean follow-up of 10.8 ± 3.0 years. After adjusting for traditional cardiovascular risk factors, CAC ≥ 300 was associated with significantly higher risk of all-cause (hazard ratio [HR]: 2.05; 95% CI: 1.49-2.82), CVD (subdistribution HR: 3.48; 95% CI: 1.81-6.70), and CHD mortality (subdistribution HR: 5.44; 95% CI: 2.02-14.66), compared with CAC = 0. When restricting the sample to individuals with BMI ≥ 35 kg/m2 , CAC ≥ 300 remained significantly associated with the highest risk. CONCLUSIONS: Among individuals with obesity, including moderate-severe obesity, CAC strongly predicts all-cause, CVD, and CHD mortality and may serve as an effective cardiovascular risk stratification tool to prioritize the allocation of therapies for weight management.

Association of triglyceride levels with adverse cardiovascular events in patients with ST-segment elevation myocardial infarction.

Although there is an established association between elevated triglyceride (eTG, ≥175 mg/dl) levels and adverse cardiovascular events, some studies have suggested that eTG levels may be linked to neutral or even improved clinical outcomes, particularly among patients with acute myocardial infarction. However, these studies had certain limitations, including small sample sizes, heterogeneous study populations, and inadequate statistical adjustments. To address these limitations, we conducted an analysis of 5347 patients with ST-segment elevation myocardial infarction (STEMI) between March 2003 and December 2020, using a prospective registry-based cohort from two large, regional STEMI centers. We used a triglyceride level of 175 mg/dl as the cutoff point for eTG levels. Of the study participants, 24.5% (n = 1312) had eTG levels. These patients were more likely to be younger, male, and have a higher number of cardiovascular risk factors compared to those with low TG levels. Despite these unfavorable cardiovascular risk profiles, patients with eTG levels had lower unadjusted risks of 1-year major adverse cardiac events (MACE) -a composite of myocardial infarction, stroke, and death- than those with low TG levels (8.8% vs. 11%, p = 0.034). However, after adjusting for certain clinical factors and lipid profile, eTG levels were not associated with a lower 1-year MACE (aHR: 1.10 (0.71-1.70), p = 0.7). In conclusion, a quarter of STEMI patients had eTG levels and these patients had comparable long-term cardiovascular outcomes compared to those with low TG levels after controlling for clinical factors and lipid profile.

Integrated smoking cessation and mood management following acute coronary syndrome: Protocol for the post-acute cardiac event smoking (PACES) trial.

BACKGROUND: Approximately 400,000 people who smoke cigarettes survive Acute Coronary Syndrome (ACS; unstable angina, ST and non-ST elevation myocardial infarction) each year in the US. Continued smoking following ACS is an independent predictor of mortality. Depressed mood post-ACS is also predictive of mortality, and smokers with depressed mood are less likely to abstain from smoking following an ACS. A single, integrated treatment targeting depressed mood and smoking could be effective in reducing post-ACS mortality. METHOD/DESIGN: The overall aim of the current study is to conduct a fully powered efficacy trial enrolling 324 smokers with ACS and randomizing them to 12 weeks of an integrated smoking cessation and mood management treatment [Behavioral Activation Treatment for Cardiac Smokers (BAT-CS)] or control (smoking cessation and general health education). Both groups will be offered 8 weeks of the nicotine patch if medically cleared. Counseling in both arms will be provided by tobacco treatment specialists. Follow-up assessments will be conducted at end-of-treatment (12-weeks) and 6, 9, and 12 months after hospital discharge. We will track major adverse cardiac events and all-cause mortality for 36 months post-discharge. Primary outcomes are depressed mood and biochemically validated 7-day point prevalence abstinence from smoking over 12 months. DISCUSSION: Results of this study will inform smoking cessation treatments post-ACS and provide unique data on the impact of depressed mood on success of post-ACS health behavior change attempts. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03413423. Registered 29 January 2018. https://beta. CLINICALTRIALS: gov/study/NCT03413423 .

Estimated versus observed 10-year atherosclerotic cardiovascular event rates in a rural population-based health initiative: The Heart of New Ulm Project.

Objective: Assess discrepancy between estimated 10-year atherosclerotic cardiovascular disease (ASCVD) risk and observed 10-year event rates in a rural population participating in cardiovascular health initiative. Methods: The study included a rural sample of individuals participating in the Heart of New Ulm (HONU), a population-based health initiative aimed at reducing ASCVD risk in a rural community. HONU conducted over 100 baseline screening events with 5221 individuals participating in 2009. For this analysis, we included participants who were aged 40-79 years, free of ASCVD at baseline, and had adequate data to calculate 10-year ASCVD risk. Electronic health record data and state death records were used to determine rates of non-fatal myocardial infarction and stroke, and ASCVD death from 2010-2019. ASCVD event rates were compared to estimated 10-year risks calculated using the Pooled Cohort Equations, stratified by sex and clinically relevant risk categories. Results: The sample (n = 2819, mean ± SD age 56.1 ± 9.9 years, 59.6% female) had a low prevalence of tobacco use (8.1% current smokers) and diabetes (6.5%) and a high prevalence of hypertension (44.4%) and hyperlipidemia (56.6%). The median estimated 10-year ASCVD risk for the entire sample was 5.7% (IQR 2.3-13.5%) with an observed 10-year ASCVD event rate of 3.4%. The largest gap between observed and estimated risk was in those at intermediate/high (≥7.5%) ASCVD risk (median 10-year risk 15.8% [IQR 10.4-29.0], observed ASCVD event rate 6.4%). Conclusio: In a sample of rural participants exposed to a multifaceted ASCVD prevention initiative, observed rates of ASCVD were substantially lower compared to estimated ASCVD risk. The potential for significantly lower than predicted ASCVD event rates in certain populations should be included in the clinician-patient risk discussion.

Coronary Artery Calcium Dispersion and Cause-Specific Mortality.

Coronary artery calcium (CAC) measures subclinical atherosclerosis and improves risk stratification. CAC characteristics-including vessel(s) involved, number of vessels, volume, and density-have been shown to differentially impact risk. We assessed how dispersion-either the number of calcified vessels or CAC phenotype (diffuse, normal, and concentrated)-impacted cause-specific mortality. The CAC Consortium is a retrospective cohort of 66,636 participants without coronary heart disease (CHD) who underwent CAC scoring. This study included patients with CAC >0 (n = 28,147). CAC area, CAC density, and CAC phenotypes (derived from the index of diffusion = 1 - [CAC in most concentrated vessel/total Agatston score]) were calculated. The associations between CAC characteristics and cause-specific mortality were assessed. The participant details included (n = 28,147): mean age 58.3 years, 25% female, 89.6% White, and 66% had 2+ calcified vessels. Diabetes, hypertension, and hyperlipidemia were predictors of multivessel involvement (p <0.001). After controlling for the overall CAC score, those with 4-vessel CAC involvement had more CAC area and less dense calcifications than those with 1-vessel. There was a graded increase in all-cause and cardiovascular disease (CVD)- and CHD-specific mortality as the number of calcified vessels increased. Among those with ≥2 vessels involved (n = 18,516), a diffuse phenotype was associated with a higher CVD-specific mortality and had a trend toward higher all-cause and CHD-specific mortality than a concentrated CAC phenotype. Diffuse CAC involvement was characterized by less dense calcification, more CAC area, multiple coronary vessel involvement, and presence of certain traditional risk factors. There is a graded increase in all-cause and CVD- and CHD-specific mortality with increasing CAC dispersion.

Mortality impact of low CAC density predominantly occurs in early atherosclerosis: explainable ML in the CAC consortium.

BACKGROUND: Machine learning (ML) models of risk prediction with coronary artery calcium (CAC) and CAC characteristics exhibit high performance, but are not inherently interpretable. OBJECTIVES: To determine the direction and magnitude of impact of CAC characteristics on 10-year all-cause mortality (ACM) with explainable ML. METHODS: We analyzed asymptomatic subjects in the CAC consortium. We trained ML models on 80% and tested on 20% of the data with XGBoost, using clinical characteristics â€‹+ â€‹CAC (ML 1) and additional CAC characteristics of CAC density and number of calcified vessels (ML 2). We applied SHAP, an explainable ML tool, to explore the relationship of CAC and CAC characteristics with 10-year all-cause and CV mortality. RESULTS: 2376 deaths occurred among 63,215 patients [68% male, median age 54 (IQR 47-61), CAC 3 (IQR 0-94.3)]. ML2 was similar to ML1 to predict all-cause mortality (Area Under the Curve (AUC) 0.819 vs 0.821, p â€‹= â€‹0.23), but superior for CV mortality (0.847 vs 0.845, p â€‹= â€‹0.03). Low CAC density increased mortality impact, particularly ≤0.75. Very low CAC density ≤0.75 was present in only 4.3% of the patients with measurable density, and 75% occurred in CAC1-100. The number of diseased vessels did not increase mortality overall when simultaneously accounting for CAC and CAC density. CONCLUSION: CAC density contributes to mortality risk primarily when it is very low ≤0.75, which is primarily observed in CAC 1-100. CAC and CAC density are more important for mortality prediction than the number of diseased vessels, and improve prediction of CV but not all-cause mortality. Explainable ML techniques are useful to describe granular relationships in otherwise opaque prediction models.

Association between hypercholesterolemia and mortality risk among patients referred for cardiac imaging test: Evidence of a "cholesterol paradox?"

AIM: Some observational studies have observed a lower, rather than higher, mortality rate in association with hypercholesterolemia during follow-up of patients after cardiac stress testing. We aim to assess the relationship of hypercholesterolemia and other CAD risk factors to mortality across a wide spectrum of patients referred for various cardiac tests. METHODS AND RESULTS: We identified four cardiac cohorts: 64,357 patients undergoing coronary artery calcium (CAC) scanning, 10,814 patients undergoing coronary CT angiography (CCTA), 31,411 patients without known CAD undergoing stress/rest single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI), and 5051 patients with known CAD undergoing stress/rest SPECT-MPI. Each cohort was followed for all-cause mortality using risk-adjusted Cox models. We pooled the hazard ratios between cohorts with a random effects model. Baseline risk varied markedly among cohorts, from an annualized mortality rate of 0.31%/year in CAC patients to 3.63%/year among SPECT-MPI patients with known CAD. Hypertension, diabetes, and smoking were each associated with increased mortality in each patient cohort (pooled hazard ratio[95% CI]: 1.38[1.33-1.44], 1.88[1.76-2.00], and 1.67[1.48-1.86], respectively). By contrast, hypercholesterolemia was associated with decreased rather than increased mortality (pooled hazard ratio[95% CI]: 0.71[0.58-0.84]). Analysis of serum lipids among 7744 patients undergoing CAC or CCTA scanning revealed an inverse relationship between LDL cholesterol and mortality. CONCLUSIONS: Among a broad spectrum of patients referred for a variety of cardiac tests and ranging from low to high clinical risk, hypercholesterolemia was not associated with increased mortality risk. Our findings suggest that hypercholesterolemia may be sensitive to confounding by other clinical factors and post-test treatment changes in patient populations.

Discordance Between Coronary Artery Calcium Area and Density Predicts Long-Term Atherosclerotic Cardiovascular Disease Risk.

BACKGROUND: Coronary artery calcium (CAC) is commonly quantified as the product of 2 generally correlated measures: plaque area and calcium density. OBJECTIVES: The authors sought to determine whether discordance between calcium area and density has long-term prognostic importance in atherosclerotic cardiovascular disease (ASCVD) risk. METHODS: The authors studied 10,373 primary prevention participants from the CAC Consortium with CAC >0. Based on their median values, calcium area and mean calcium density were divided into 4 mutually exclusive concordant/discordant groups. Cox proportional hazards regression assessed the association of calcium area/density groups with ASCVD mortality over a median of 11.7 years, adjusting for traditional risk factors and the Agatston CAC score. RESULTS: The mean age was 56.7 years, and 24% were female. The prevalence of plaque discordance was 19% (9% low calcium area/high calcium density, 10% high calcium area/low calcium density). Female sex (odds ratio [OR]: 1.48 [95% CI: 1.27-1.74]) and body mass index (OR: 0.81 [95% CI: 0.76-0.87], per 5 kg/m2 higher) were significantly associated with high calcium density discordance, whereas diabetes (OR: 2.23 [95% CI: 1.85-3.19]) was most strongly associated with discordantly low calcium density. Compared to those with low calcium area/low calcium density, individuals with low calcium area/high calcium density had a 71% lower risk of ASCVD death (HR: 0.29 [95% CI: 0.09-0.95]). CONCLUSIONS: For a given CAC score, high calcium density relative to plaque area confers lower long-term ASCVD risk, likely serving as an imaging marker of biological resilience for lesion vulnerability. Additional research is needed to define a robust definition of calcium area/density discordance for routine clinical risk prediction.

Highlights in ASCVD Primary Prevention for 2021.

This review examines key studies published in 2021 that are related to primary prevention of atherosclerotic cardiovascular disease (ASCVD). Major randomized clinical trials (RCTs) concerning traditional risk factors or ASCVD events, meta-analyses, and key observational studies related to primary prevention of ASCVD were considered. The review includes interventions for weight loss, cardiometabolic and renal disease, blood pressure control, diet, and the occurrence of cardiovascular disease events. A few studies considered both primary and secondary prevention populations. The review is not exhaustive. We did not include studies that focused on heart failure or clinical presentations that may be difficult to classify, such as acute or chronic ischemic cardiovascular disease without myocardial infarction. Our purpose was to highlight recent research that will help the reader stay abreast of the changing field of cardiovascular prevention.

Omega-3 fatty acids, subclinical atherosclerosis, and cardiovascular events: Implications for primary prevention.

BACKGROUND AND AIMS: High-dose eicosapentaenoic acid (EPA) therapy was beneficial in high-risk patients without clinical cardiovascular disease (CVD). Whether higher plasma levels of EPA and docosahexaenoic acid (DHA) have similar benefits in those without subclinical CVD is unclear. We aim to evaluate the interplay between plasma omega-3 fatty acids and coronary artery calcium (CAC) in relation to CVD events. METHODS: We examined 6568 participants from the Multi-Ethnic Study of Atherosclerosis (MESA) with plasma EPA and DHA levels and CAC measured at baseline. The primary outcome was incident CVD events (myocardial infarction, angina, cardiac arrest, stroke, CVD death). Hazard ratios for the primary outcome were adjusted for potential confounder using Cox regression. RESULTS: Mean ± SD age was 62.1 ± 10.2 years and 52.9% were females. The median follow-up time was 15.6 years. Higher loge(EPA) (adjusted hazard ratio, aHR = 0.83; 95% CI, 0.74-0.94) and loge(DHA) (aHR = 0.79; 95% CI, 0.66-0.96) were independently associated with fewer CVD events. The difference in absolute CVD event rates between lowest vs. highest EPA tertile increased at higher CAC levels. The adjusted HR for highest vs. lowest EPA tertile within CAC = 0 was 1.02 (95% CI, 0.72-1.46), CAC = 1-99 was 0.71 (95% CI, 0.51-0.99), and CAC≥100 was 0.67 (95% CI, 0.52-0.84). A similar association was seen in tertiles of DHA by CAC category. CONCLUSIONS: In an ethnically diverse population free of clinical CVD, higher plasma omega-3 fatty acid levels were associated with fewer long-term CVD events. The absolute decrease in CVD events with higher omega-3 fatty acid levels was more apparent at higher CAC scores.

Distribution of Coronary Artery Calcium by Age, Sex, and Race Among Patients 30-45 Years Old.

BACKGROUND: Coronary artery calcium (CAC) is a measure of atherosclerotic burden and is well-validated for risk stratification in middle- to older-aged adults. Few studies have investigated CAC in younger adults, and there is no calculator for determining age-, sex-, and race-based percentiles among individuals aged <45 years. OBJECTIVES: The purpose of this study was to determine the probability of CAC >0 and develop age-sex-race percentiles for U.S. adults aged 30-45 years. METHODS: We harmonized 3 datasets-CARDIA (Coronary Artery Risk Development in Young Adults), the CAC Consortium, and the Walter Reed Cohort-to study CAC in 19,725 asymptomatic Black and White individuals aged 30-45 years without known atherosclerotic cardiovascular disease. After weighting each cohort equally, the probability of CAC >0 and age-sex-race percentiles of CAC distributions were estimated using nonparametric techniques. RESULTS: The prevalence of CAC >0 was 26% among White males, 16% among Black males, 10% among White females, and 7% among Black females. CAC >0 automatically placed all females at >90th percentile. CAC >0 placed White males at the 90th percentile at age 34 years compared with Black males at age 37 years. An interactive webpage allows one to enter an age, sex, race, and CAC score to obtain the corresponding estimated percentile. CONCLUSIONS: In a large cohort of U.S. adults aged 30-45 years without symptomatic atherosclerotic cardiovascular disease, the probability of CAC >0 varied by age, sex, and race. Estimated percentiles may help interpretation of CAC scores among young adults relative to their age-sex-race matched peers and can henceforth be included in CAC score reporting.

Coronary Artery Calcium for Risk Stratification of Sudden Cardiac Death: The Coronary Artery Calcium Consortium.

BACKGROUND: Coronary artery calcium (CAC) is a marker of plaque burden. Whether CAC improves risk stratification for incident sudden cardiac death (SCD) beyond atherosclerotic cardiovascular disease (ASCVD) risk factors is unknown. OBJECTIVES: SCD is a common initial manifestation of coronary heart disease (CHD); however, SCD risk prediction remains elusive. METHODS: The authors studied 66,636 primary prevention patients from the CAC Consortium. Multivariable competing risks regression and C-statistics were used to assess the association between CAC and SCD, adjusting for demographics and traditional risk factors. RESULTS: The mean age was 54.4 years, 33% were women, 11% were of non-White ethnicity, and 55% had CAC >0. A total of 211 SCD events (0.3%) were observed during a median follow-up of 10.6 years, 91% occurring among those with baseline CAC >0. Compared with CAC = 0, there was a stepwise higher risk (P trend < 0.001) in SCD for CAC 100 to 399 (subdistribution hazard ratio [SHR]: 2.8; 95% CI: 1.6-5.0), CAC 400 to 999 (SHR: 4.0; 95% CI: 2.2-7.3), and CAC >1,000 (SHR: 4.9; 95% CI: 2.6-9.9). CAC provided incremental improvements in the C-statistic for the prediction of SCD among individuals with a 10-year risk <7.5% (ΔC-statistic = +0.046; P = 0.02) and 7.5% to 20% (ΔC-statistic = +0.069; P = 0.003), which were larger when compared with persons with a 10-year risk >20% (ΔC-statistic = +0.01; P = 0.54). CONCLUSIONS: Higher CAC burden strongly associates with incident SCD beyond traditional risk factors, particularly among primary prevention patients with low-intermediate risk. SCD risk stratification can be useful in the early stages of CHD through the measurement of CAC, identifying patients most likely to benefit from further downstream testing.

Coronary Artery Calcium for Risk Assessment in Young Adults.

PURPOSE OF REVIEW: To review the prognostic significance and clinical utility of coronary artery calcium (CAC) for risk assessment for atherosclerotic cardiovascular disease (ASCVD) in younger adults. RECENT FINDINGS: Data from over 3000 young adults (mean age of 40.3 ± 3.6 followed for 12.5 years) in the CARDIA registry found that in an asymptomatic, community representative sample, there was a low prevalence of CAC (~ 10%) but those with CAC had an exponential increase in CAC over time and significantly higher rates of ASCVD events. Alternatively, data from the CAC consortium analyzed 22,346 asymptomatic individuals undergoing CAC for clinical indications (mean age 43.5 ± 4.5 years, followed for 13 ± 4 years) and found a much higher prevalence of CAC at 34% with rates of coronary heart disease mortality that varied significantly according to CAC. In younger adults, CAC provides clear prognostic value and can be considered in select individuals with uncertainties about their ASCVD risk or the benefit of preventive therapies.