A loss-of-function CCR2 variant is associated with lower cardiovascular risk

Background and Aims

Ample evidence links CCL2, a key chemokine governing monocyte trafficking, with atherosclerosis. However, it remains unknown whether targeting the CCL2 receptor CCR2 could provide protection against cardiovascular disease.

Methods

Computationally predicted damaging (REVEL>0.5) variants within CCR2 were detected in whole-exome-sequencing data from 454,775 UK Biobank participants and tested for association with cardiovascular endpoints in gene-burden tests. Given the key role of CCR2 in monocyte mobilization, variants associated with lower monocyte count were prioritized for experimental validation. The response to CCL2 of human cells transfected with these variants was tested in migration and cAMP assays. Validated loss-of-function variants were tested for association with cardiovascular endpoints, atherosclerosis burden, and vascular risk factors. Significant associations were replicated in six independent datasets (n=1,062,595).

Results

Carriers of 45 predicted damaging CCR2 variants were at lower risk of myocardial infarction and coronary artery disease. One of these variants (M249K) was associated with lower monocyte count and decreased signaling and chemoattraction in response to CCL2. While M249K showed no association with conventional vascular risk factors, it was consistently associated with a lower risk of myocardial infarction (Odds Ratio: 0.66 95% Confidence Interval: 0.54-0.81,p=6.1×10-5) and coronary artery disease(Odds Ratio: 0.74 95% Confidence Interval: 0.62-0.87, p=2.9×10-4) in the UK Biobank and in six replication cohorts. In a phenome-wide association study, there was no evidence of higher infections risk among M249K carriers.

Conclusions

Carriers of an experimentally confirmed loss-of-function CCR2 variant are at a lower lifetime risk of myocardial infarction and coronary artery disease without carrying a higher infection risk. Our findings provide genetic support for the translational potential of CCR2-targeting as an atheroprotective approach.

Associations of Fecal Microbiota with Ectopic Fat in African Caribbean Men

OBJECTIVE

The gut microbiome has been associated with visceral fat (VAT) in European and Asian populations; however, associations with VAT and with ectopic fats among African-ancestry individuals are not known. Our objective was to investigate cross-sectional associations of fecal microbiota diversity and composition with VAT and ectopic fat, as well as body mass index (BMI), among middle-aged and older African Caribbean men.

METHODS

We included in our analysis n = 193 men (mean age = 62.2 ± 7.6 years; mean BMI = 28.3 ± 4.9 kg/m2) from the Tobago Health Study. We assessed fecal microbiota using V4 16s rRNA gene sequencing. We evaluated multivariable-adjusted associations of microbiota features (alpha diversity, beta diversity, microbiota differential abundance) with BMI and with computed tomography-measured VAT and ectopic fats (pericardial and intermuscular fat; muscle and liver attenuation).

RESULTS

Lower alpha diversity was associated with higher VAT and BMI, and somewhat with higher pericardial and liver fat. VAT, BMI, and pericardial fat each explained similar levels of variance in beta diversity. Gram-negative Prevotellaceae and Negativicutes microbiota showed positive associations, while gram-positive Ruminococcaceae microbiota showed inverse associations, with ectopic fats.

CONCLUSIONS

Fecal microbiota features associated with measures of general adiposity also extend to metabolically pernicious VAT and ectopic fat accumulation in older African-ancestry men.

Non-alcoholic fatty liver modifies associations of body mass index and waist circumference with cardiometabolic risk: The CARDIA study

Background

Non-alcoholic fatty liver disease (NAFLD) is recognized as a prevalent determinant of cardiometabolic diseases. The association between NAFLD and obesity warrants further research on how NAFLD modifies associations between body mass index (BMI) and Waist circumference (WC) with cardiometabolic risk (CMR).

Objective

This study assessed whether NAFLD modifies associations between BMI and WC with 5-year changes in CMR in 2366 CARDIA study participants.

Methods

Non-contrast CT was used to quantify liver attenuation, with ≤51 Hounsfield Units (HU) used to define NAFLD in the absence of secondary causes of excess liver fat. The dependent variable was the average Z score of fasting glucose, insulin, triglycerides [log], (-) high-density lipoprotein cholesterol (HDL-C), and systolic blood pressure(SBP). Multivariable linear regression was used to estimate the associations between BMI and WC with CMR. Effect modification by NAFLD was assessed by an interaction term between NAFLD and BMI or WC.

Results

The final sample had 539 (23%) NAFLD cases. NAFLD modified the association of BMI and WC with CMR (interaction p < 0.0001 for both). BMI and WC were associated with CMR in participants without NAFLD (p < 0.001), but not among those with NAFLD. Participants with NAFLD and normal BMI and WC had CMR estimates that were higher than those without NAFLD in the obese categories. Among those without NAFLD the 5 years CMR change estimate was 0.09 (95% CI: 0.062, 0.125) for BMI ≥30 kg/m2 compared to -0.06 (-0.092, -0.018) for BMI < 25 kg/m2, and among those with NAFLD, these estimates were 0.15 (0.108, 0.193) and 0.16 (-0.035, 0.363).

Conclusions

NAFLD modifies associations of BMI and WC with CMR. Compared with BMI and WC, NAFLD was more strongly associated with CMR. In the presence of NAFLD, BMI and WC were not associated with CMR. These findings have implications for clinical screening guidelines.

Carotid Intima-Media Thickness and Improved Stroke Risk Assessment in Hypertensive Black Adults

BACKGROUND

We aim to determine the added value of carotid intima-media thickness (cIMT) in stroke risk assessment for hypertensive Black adults.

METHODS

We examined 1,647 participants with hypertension without a history of cardiovascular (CV) disease, from the Jackson Heart Study. Cox regression analysis estimated hazard ratios (HRs) for incident stroke per standard deviation increase in cIMT and quartiles while adjusting for baseline variables. We then evaluated the predictive capacity of cIMT when added to the pool cohort equations (PCEs).

RESULTS

The mean age at baseline was 57 ± 10 years. Each standard deviation increase in cIMT (0.17 mm) was associated with approximately 30% higher risk of stroke (HR 1.27, 95% confidence interval: 1.08-1.49). Notably, cIMT proved valuable in identifying residual stroke risk among participants with well-controlled blood pressure, showing up to a 56% increase in the odds of stroke for each 0.17 mm increase in cIMT among those with systolic blood pressure <120 mm Hg. Additionally, the addition of cIMT to the PCE resulted in the reclassification of 58% of low to borderline risk participants with stroke to a higher-risk category and 28% without stroke to a lower-risk category, leading to a significant net reclassification improvement of 0.22 (0.10-0.30).

CONCLUSIONS

In this community-based cohort of middle-aged Black adults with hypertension and no history of CV disease at baseline, cIMT is significantly associated with incident stroke and enhances stroke risk stratification.

Comparing coronary artery cross-sectional area among asymptomatic South Asian, White, and Black participants: the MASALA and CARDIA studies

BACKGROUND

South Asian individuals have high risk of atherosclerotic cardiovascular disease (ASCVD). Some investigators suggest smaller coronary artery size may be partially responsible.

METHODS

We compared the left anterior descending (LAD) artery cross-sectional area (CSA) (lumen and arterial wall) among South Asians in the Mediators of Atherosclerosis in South Asians Living in America (MASALA) study with White and Black participants in the Coronary Artery Risk Development in Young Adults (CARDIA) study, adjusting for BMI, height, and other ASCVD risk factors. We used thin-slice non-contrast cardiac computed tomography to measure LAD CSA. We used linear regression models to determine whether race/ethnicity was associated with LAD CSA after adjusting for demographic factors, BMI, height, coronary artery calcium (CAC), and traditional cardiovascular risk factors.

RESULTS

Our sample included 3,353 participants: 513 self-identified as South Asian (44.4% women), 1286 as Black (59.6% women), and 1554 as White (53.5% women). After adjusting for age, BMI, height, there was no difference in LAD CSA between South Asian men and women compared to White men and women, respectively. After full adjustment for CVD risk factors, LAD CSA values were: South Asian women (19.9 mm2, 95% CI [18.8 - 20.9]) and men (22.3 mm2, 95% CI [21.4 - 23.2]; White women (20.0 mm2, 95% CI [19.4-20.5]) and men (23.6 mm2, 95% CI [23.0-24.2]); and Black women (21.6 mm2, 95% CI [21.0 - 22.2]) and men (26.0 mm2, 95% CI [25.3 - 26.7]). Height, BMI, hypertension, CAC, and age were positively associated with LAD CSA; current and former cigarette use were inversely associated.

CONCLUSIONS

South Asian men and women have similar LAD CSA to White men and women, and smaller LAD CSA compared to Black men and women, respectively, after accounting for differences in body size. Future studies should determine whether LAD CSA is associated with future ASCVD events.

Epigenetic Aging Is Associated With Measures of Midlife Muscle Volume and Attenuation in CARDIA Study

BACKGROUND

GrimAge acceleration (GAA), an epigenetic marker that represents physiologic aging, is associated with age-related diseases including cancer and cardiovascular diseases. However, the associations between GAA and muscle mass and function are unknown.

METHODS

We estimated measures of GAA in 1 118 Black and White participants from the Coronary Artery Risk Development in Young Adults (CARDIA) Study at exam years (Y) 15 (2000-2001) and 20 (2005-2006). Abdominal muscle composition was measured using CT scans at the Y25 (2010-2011) visit. We used multivariate regression models to examine associations of GAA estimates with muscle imaging measurements.

RESULTS

In the CARDIA study, each 1-year higher GAA was associated with an average 1.1% (95% confidence interval [CI]: 0.6%, 1.5%) higher intermuscular adipose tissue (IMAT) volume for abdominal muscles. Each 1-year higher GAA was associated with an average -0.089 Hounsfield unit (HU; 95% CI: -0.146, -0.032) lower lean muscle attenuation and an average -0.049 HU (95% CI: -0.092, -0.007) lower IMAT attenuation for abdominal muscles. Stratified analyses showed that GAA was more strongly associated with higher abdominal muscle IMAT volume in females and significantly associated with lower lean muscle attenuation for White participants only.

CONCLUSIONS

Higher GAA is associated with higher abdominal muscle IMAT volume and lower lean muscle attenuation in a midlife population.

Diet quality is associated with adipose tissue and muscle mass: the Coronary Artery Risk Development in Young Adults (CARDIA) study

BACKGROUND

Aging is associated with changes in body composition, and preventing loss of muscle mass and accumulation of excess adipose tissue in middle-aged adults may reduce age-related conditions at older ages. Dietary intake is one lifestyle factor shown to improve or maintain body composition. However, few studies have examined the Healthy Eating Index2015 (HEI2015), a measure of diet quality, and the association with body composition in adult men and women.

METHODS

Participant data (n = 3017) from the Coronary Artery Risk Development in Young Adults (CARDIA) study were used to examine the associations of the HEI2015 with body composition measures at Year 25 (Y25), including (1) 25 year-change in weight, body mass index (BMI), and waist circumference and (2) a computed tomography (CT) scan at Y25 measured muscle mass, muscle quality (better quality = less lipid within the muscle), and adipose tissue depots visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and adipose within skeletal muscle (intermuscular adipose tissue; IMAT). Dietary intake was assessed by a diet history three times over 20 years, at years 0, 7, and 20. HEI2015, averaged over three exams, was created and categorized into quintiles. Multiple regression analysis evaluated the associations of body composition stratified across quintiles of HEI2015 adjusted for demographic characteristics, energy intake, lifestyle factors, and baseline anthropometric measures as appropriate. Race-sex interaction was tested (Pinteraction  > 0.30).

RESULTS

Over 25 years of follow-up, averaged HEI2015 was significantly and inversely associated with weight gain (Quintile 1 (Q1) 37.3 lb vs. 32.9 in Q5; Ptrend  = 0.01), change in BMI (Q1 5.8 kg/m2 vs. 5.0 in Q5; Ptrend  = 0.005), and change in waist circumference (Q1 17.5 cm vs. 15.2 cm in Q5; Ptrend  < 0.001). By Y25, HEI2015 was inversely associated with VAT Q1 136.8 cm3 vs. 116.6 in Q5; Ptrend  < 0.001) and IMAT volumes (Q1 9.52 vs. 8.12 cm3 in Q5; Ptrend  < 0.001). Although total muscle volume declined (Ptrend  = 0.03), lean muscle mass volume was similar across quintiles (Ptrend  = 0.55). The IMAT/total muscle mass ratio declined across HEI2015 quintiles (Ptrend  < 0.001). Finally, higher HEI2015 was associated with better muscle quality at Y25 (higher value = less lipid within the muscle; Q1 41.1 vs. 42.2 HU in Q5; Ptrend  = 0.002). HEI2015 was nonlinearly, but inversely, associated with SAT (nonlinear P = 0.011).

CONCLUSIONS

Improving diet quality in young to middle-aged adults is a recommended strategy to promote better measures of body composition. Our study findings suggest that healthier food choices may influence body composition.

Consumption of foods and beverages rich in added sugar associated with incident metabolic syndrome: Coronary Artery Risk Development in Young Adults (CARDIA) study

AIMS

Numerous studies report positive associations between total carbohydrate (CHO) intake and incident metabolic syndrome (MetS), but few differentiate quality or type of CHO relative to MetS. We examined source of CHO intake, including added sugar (AS), AS-rich CHO foods and sugar-sweetened beverages (SSBs) associated with incident MetS in adults enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study.

METHODS

Among 3154 Black American and White American women and men aged 18-30 years at baseline, dietary intake was assessed by diet history three times over 20 years. Sources of AS-rich CHO foods and beverages include sugar-rich refined grain products, candy, sugar products, and SSBs. Incident MetS was created according to standard criteria. Time-dependent Cox proportional-hazards regression analysis evaluated the associations of incident MetS across quintiles of cumulative intakes of AS-rich CHO foods and beverages, AS, and SSBs adjusted for potential confounding factors over 30 years of follow-up.

RESULTS

The associations of AS-rich CHO foods and beverages, AS, and SSB intakes with incident MetS were consistent. Compared to the lowest intake, the greatest intake of AS-rich CHOs, AS, and SSBs were associated with 59% (ptrend<0.001), 44% (ptrend=0.01), and 34% (ptrend=0.03) higher risk of developing MetS, respectively. As expected, diet quality was lower across increasing quintiles of AS-rich CHO foods and beverages, AS, and SSBs (all ptrend<0.001).

CONCLUSION

Our study findings are consistent with an elevated risk of developing MetS with greater consumption of AS, AS-rich CHO foods, and SSBs which support consuming fewer AS-rich CHO foods and SSBs.

Chronic Stress and Cardiovascular Events: Findings From the CARDIA Study

INTRODUCTION

Higher levels of perceived stress are associated with adverse cardiovascular health. It is plausible that these associations are attenuated among individuals with positive psychological factors such as social support and health-enhancing behaviors. Therefore, this study examined longitudinal associations of chronic stress with cardiovascular disease (CVD) events, and whether social support and physical activity (PA) modify these associations.

METHODS

Data from 3,401 adults (mean age 40.2 years; 46.7% Black; 56.2% women) from the Coronary Artery Risk Development in Young Adults (CARDIA) study, with no prior CVD event in 2000-2001 were analyzed. Chronic stress lasting ≥6 months across 5 life domains (work, financial, relationships, health of self, and health of close other) was self-reported. Adjudicated CVD events (fatal/or nonfatal CVD event) were ascertained yearly through 2020. PA and social support were self-reported via questionnaires. Statistical analyses were conducted in 2023 using multivariable stepwise Accelerated Failure Time analysis to assess associations between key study variables.

RESULTS

The mean chronic stress score was 1.30±1.33 stressors and, by 2020, 220 participants had experienced a CVD event. Chronic stress was associated with lowered survival (time ratio: 0.92; 95% CI: 0.854-0.989), when adjusted for sociodemographic and lifestyle variables but no longer significant when adjusting for clinical factors. Neither PA nor social support were significant modifiers (all ps>0.05).

CONCLUSIONS

Chronic stress was associated with the risk of having a CVD event among middle-aged adults, due at least in part to clinical mediators. Studies should continue exploring positive psychosocial and behavioral factors that may modify this association.

Age-related Muscle Fat Infiltration in Lung Screening Participants: Impact of Smoking Cessation

Rationale

Skeletal muscle fat infiltration progresses with aging and is worsened among individuals with a history of cigarette smoking. Many negative impacts of smoking on muscles are likely reversible with smoking cessation.

Objectives

To determine if the progression of skeletal muscle fat infiltration with aging is altered by smoking cessation among lung cancer screening participants.

Methods

This was a secondary analysis based on the National Lung Screening Trial. Skeletal muscle attenuation in Hounsfield unit (HU) was derived from the baseline and follow-up low-dose CT scans using a previously validated artificial intelligence algorithm. Lower attenuation indicates greater fatty infiltration. Linear mixed-effects models were constructed to evaluate the associations between smoking status and the muscle attenuation trajectory.

Measurements and Main Results

Of 19,019 included participants (age: 61 years, 5 [SD]; 11,290 males), 8,971 (47.2%) were actively smoking cigarettes. Accounting for body mass index, pack-years, percent emphysema, and other confounding factors, actively smoking predicted a lower attenuation in both males (β0 =-0.88 HU, P<.001) and females (β0 =-0.69 HU, P<.001), and an accelerated muscle attenuation decline-rate in males (β1=-0.08 HU/y, P<.05). Age-stratified analyses indicated that the accelerated muscle attenuation decline associated with smoking likely occurred at younger age, especially in females.

Conclusions

Among lung cancer screening participants, active cigarette smoking was associated with greater skeletal muscle fat infiltration in both males and females, and accelerated muscle adipose accumulation rate in males. These findings support the important role of smoking cessation in preserving muscle health.

Type 2 Diabetes Modifies the Association of CAD Genomic Risk Variants With Subclinical Atherosclerosis

BACKGROUND

Individuals with type 2 diabetes (T2D) have an increased risk of coronary artery disease (CAD), but questions remain about the underlying pathology. Identifying which CAD loci are modified by T2D in the development of subclinical atherosclerosis (coronary artery calcification [CAC], carotid intima-media thickness, or carotid plaque) may improve our understanding of the mechanisms leading to the increased CAD in T2D.

METHODS

We compared the common and rare variant associations of known CAD loci from the literature on CAC, carotid intima-media thickness, and carotid plaque in up to 29 670 participants, including up to 24 157 normoglycemic controls and 5513 T2D cases leveraging whole-genome sequencing data from the Trans-Omics for Precision Medicine program. We included first-order T2D interaction terms in each model to determine whether CAD loci were modified by T2D. The genetic main and interaction effects were assessed using a joint test to determine whether a CAD variant, or gene-based rare variant set, was associated with the respective subclinical atherosclerosis measures and then further determined whether these loci had a significant interaction test.

RESULTS

Using a Bonferroni-corrected significance threshold of P<1.6×10-4, we identified 3 genes (ATP1B1, ARVCF, and LIPG) associated with CAC and 2 genes (ABCG8 and EIF2B2) associated with carotid intima-media thickness and carotid plaque, respectively, through gene-based rare variant set analysis. Both ATP1B1 and ARVCF also had significantly different associations for CAC in T2D cases versus controls. No significant interaction tests were identified through the candidate single-variant analysis.

CONCLUSIONS

These results highlight T2D as an important modifier of rare variant associations in CAD loci with CAC.

Young Adult Physical Activity Trajectories and Midlife Nonalcoholic Fatty Liver Disease

Importance

Physical activity (PA) is recommended for preventing and treating nonalcoholic fatty liver disease (NAFLD). Yet, how long-term patterns of intensity-based physical activity, including moderate-intensity PA (MPA) and vigorous-intensity PA (VPA), might affect the prevalence of NAFLD in middle age remains unclear.

Objective

To identify distinct intensity-based PA trajectories from young to middle adulthood and examine the associations between PA trajectories and NAFLD prevalence in midlife.

Design, Setting, and Participants

This population-based cohort of 2833 participants used the Coronary Artery Risk Development in Young Adults study data. The setting included field clinics in Birmingham, Alabama; Chicago, Illinois; Minneapolis, Minnesota; and Oakland, California. Data analysis was completed in March 2023.

Exposures

PA was self-reported at 8 examinations over 25 years (1985-1986 to 2010-2011) and separately scored for MPA and VPA.

Main Outcomes and Measures

NAFLD was defined as liver attenuation values less than 51 Hounsfield units after exclusion of other causes of liver fat, measured using computed tomography in year 25 (2010-2011).

Results

Among a total of 2833 participants included in the sample, 1379 (48.7%) self-identified as Black, 1454 (51.3%) as White, 1206 (42.6%) as male, and 1627 (57.4%) as female from baseline (1985-1986) (mean [SD] age, 25.0 [3.6] years) to year 25 (2010-2011) (mean [SD] age, 50.1 [3.6] years). Three MPA trajectories were identified: very low stable (1514 participants [53.4%]), low increasing (1096 [38.7%]), and moderate increasing (223 [7.9%]); and 3 VPA trajectories: low stable (1649 [58.2%]), moderate decreasing (1015 [35.8%]), and high decreasing (169 [6.0%]). After adjustment for covariates (sex, age, race, study center, education, smoking status, and alcohol consumption), participants in the moderate decreasing (risk ratio [RR], 0.74; 95% CI, 0.54-0.85) and the high decreasing (RR, 0.59; 95% CI, 0.44-0.80) VPA trajectories had a lower risk of NAFLD in middle age, relative to participants in the low stable VPA trajectory. Adjustments for baseline body mass index and waist circumference attenuated these estimates, but the results remained statistically significant. The adjusted RRs across the MPA trajectories were close to null and not statistically significant.

Conclusions and Relevance

This cohort study of Black and White participants found a reduced risk of NAFLD in middle age for individuals with higher levels of VPA throughout young to middle adulthood compared with those with lower VPA levels. These results suggest the need for promoting sustainable and equitable prevention programs focused on VPA over the life course to aid in lowering NAFLD risk.

Long-term aspartame and saccharin intakes are related to greater volumes of visceral, intermuscular, and subcutaneous adipose tissue: the CARDIA study

BACKGROUND

Artificial sweetener (ArtSw) intakes have been previously associated with higher BMI in observational studies and may promote visceral and skeletal muscle adipose tissue (AT) accumulation. This study aimed to determine whether habitual, long-term ArtSw or diet beverage intakes are related to greater AT depot volumes and anthropometry-related outcomes.

METHODS

A validated diet history questionnaire was administered at baseline, year 7, and year 20 examinations in 3088 men and women enrolled in the Coronary Artery Risk Development in Young Adults cohort (CARDIA), mean age of 25.2 years and mean BMI of 24.5 kg/m2 at baseline. Volumes of visceral (VAT), intermuscular (IMAT), and subcutaneous adipose tissue (SAT) were assessed by computed tomography at year 25. Linear regression evaluated associations of aspartame, saccharin, sucralose, total ArtSw, and diet beverage intakes with AT volumes, anthropometric measures, and 25-year change in anthropometry. Cox regression estimated associations of ArtSw with obesity incidence. Adjustments were made for demographic and lifestyle factors, total energy intake, and the 2015 healthy eating index.

RESULTS

Total ArtSw, aspartame, saccharin, and diet beverage intakes were positively associated with VAT, SAT, and IMAT volumes (all ptrend ≤ 0.001), but no associations were observed for sucralose intake (all ptrend > 0.05). In addition, total ArtSw, saccharin, aspartame, and diet beverage intakes were associated with greater body mass index, body weight, waist circumference, and their increases over a 25-year period. Except for saccharin (ptrend = 0.13), ArtSw, including diet soda, was associated with greater risks of incident obesity over a median 17.5-year follow-up (all ptrend < 0.05).

CONCLUSIONS

Results suggest that long-term intakes of aspartame, saccharin, or diet soda may increase AT deposition and risk of incident obesity independent of diet quality or caloric intake. Coupled with previous evidence, alternatives to national recommendations to replace added sugar with ArtSw should be considered since both may have health consequences.

Multi-ancestry genome-wide study identifies effector genes and druggable pathways for coronary artery calcification

Coronary artery calcification (CAC), a measure of subclinical atherosclerosis, predicts future symptomatic coronary artery disease (CAD). Identifying genetic risk factors for CAC may point to new therapeutic avenues for prevention. Currently, there are only four known risk loci for CAC identified from genome-wide association studies (GWAS) in the general population. Here we conducted the largest multi-ancestry GWAS meta-analysis of CAC to date, which comprised 26,909 individuals of European ancestry and 8,867 individuals of African ancestry. We identified 11 independent risk loci, of which eight were new for CAC and five had not been reported for CAD. These new CAC loci are related to bone mineralization, phosphate catabolism and hormone metabolic pathways. Several new loci harbor candidate causal genes supported by multiple lines of functional evidence and are regulators of smooth muscle cell-mediated calcification ex vivo and in vitro. Together, these findings help refine the genetic architecture of CAC and extend our understanding of the biological and potential druggable pathways underlying CAC.

Genome-wide association meta-analysis identifies 17 loci associated with nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is common and partially heritable and has no effective treatments. We carried out a genome-wide association study (GWAS) meta-analysis of imaging (n = 66,814) and diagnostic code (3,584 cases versus 621,081 controls) measured NAFLD across diverse ancestries. We identified NAFLD-associated variants at torsin family 1 member B (TOR1B), fat mass and obesity associated (FTO), cordon-bleu WH2 repeat protein like 1 (COBLL1)/growth factor receptor-bound protein 14 (GRB14), insulin receptor (INSR), sterol regulatory element-binding transcription factor 1 (SREBF1) and patatin-like phospholipase domain-containing protein 2 (PNPLA2), as well as validated NAFLD-associated variants at patatin-like phospholipase domain-containing protein 3 (PNPLA3), transmembrane 6 superfamily 2 (TM6SF2), apolipoprotein E (APOE), glucokinase regulator (GCKR), tribbles homolog 1 (TRIB1), glycerol-3-phosphate acyltransferase (GPAM), mitochondrial amidoxime-reducing component 1 (MARC1), microsomal triglyceride transfer protein large subunit (MTTP), alcohol dehydrogenase 1B (ADH1B), transmembrane channel like 4 (TMC4)/membrane-bound O-acyltransferase domain containing 7 (MBOAT7) and receptor-type tyrosine-protein phosphatase δ (PTPRD). Implicated genes highlight mitochondrial, cholesterol and de novo lipogenesis as causally contributing to NAFLD predisposition. Phenome-wide association study (PheWAS) analyses suggest at least seven subtypes of NAFLD. Individuals in the top 10% and 1% of genetic risk have a 2.5-fold to 6-fold increased risk of NAFLD, cirrhosis and hepatocellular carcinoma. These genetic variants identify subtypes of NAFLD, improve estimates of disease risk and can guide the development of targeted therapeutics.

Performance of an automated deep learning algorithm to identify hepatic steatosis within noncontrast computed tomography scans among people with and without HIV

PURPOSE

Hepatic steatosis (fatty liver disease) affects 25% of the world's population, particularly people with HIV (PWH). Pharmacoepidemiologic studies to identify medications associated with steatosis have not been conducted because methods to evaluate liver fat within digitized images have not been developed. We determined the accuracy of a deep learning algorithm (automatic liver attenuation region-of-interest-based measurement [ALARM]) to identify steatosis within clinically obtained noncontrast abdominal CT images compared to manual radiologist review and evaluated its performance by HIV status.

METHODS

We performed a cross-sectional study to evaluate the performance of ALARM within noncontrast abdominal CT images from a sample of patients with and without HIV in the US Veterans Health Administration. We evaluated the ability of ALARM to identify moderate-to-severe hepatic steatosis, defined by mean absolute liver attenuation <40 Hounsfield units (HU), compared to manual radiologist assessment.

RESULTS

Among 120 patients (51 PWH) who underwent noncontrast abdominal CT, moderate-to-severe hepatic steatosis was identified in 15 (12.5%) persons via ALARM and 12 (10%) by radiologist assessment. Percent agreement between ALARM and radiologist assessment of absolute liver attenuation <40 HU was 95.8%. Sensitivity, specificity, positive predictive value, and negative predictive value of ALARM were 91.7% (95%CI, 51.5%-99.8%), 96.3% (95%CI, 90.8%-99.0%), 73.3% (95%CI, 44.9%-92.2%), and 99.0% (95%CI, 94.8%-100%), respectively. No differences in performance were observed by HIV status.

CONCLUSIONS

ALARM demonstrated excellent accuracy for moderate-to-severe hepatic steatosis regardless of HIV status. Application of ALARM to radiographic repositories could facilitate real-world studies to evaluate medications associated with steatosis and assess differences by HIV status.

Association of alpha-aminoadipic acid with cardiometabolic risk factors in healthy and high-risk individuals

Introduction

Plasma levels of the metabolite alpha-aminoadipic acid (2-AAA) have been associated with risk of type 2 diabetes (T2D) and atherosclerosis. However, little is known about the relationship of 2-AAA to other cardiometabolic risk markers in pre-disease states, or in the setting of comorbid disease.

Methods

We measured circulating 2-AAA using two methods in 1) a sample of 261 healthy individuals (2-AAA Study), and 2) in a sample of 134 persons comprising 110 individuals with treated HIV, with or without T2D, a population at high risk of metabolic disease and cardiovascular events despite suppression of circulating virus, and 24 individuals with T2D without HIV (HATIM Study). We examined associations between plasma 2-AAA and markers of cardiometabolic health within each cohort.

Results and discussion

We observed differences in 2-AAA by sex and race in both cohorts, with higher levels observed in men compared with women, and in Asian compared with Black or white individuals (P<0.05). There was no significant difference in 2-AAA by HIV status within individuals with T2D in the HATIM Study. We confirmed associations between 2-AAA and dyslipidemia in both cohorts, where high 2-AAA associated with low HDL cholesterol (P<0.001) and high triglycerides (P<0.05). As expected, within the cohort of people with HIV, 2-AAA was higher in the setting of T2D compared to pre-diabetes or normoglycemia (P<0.001). 2-AAA was positively associated with body mass index (BMI) in the 2-AAA Study, and with waist circumference and measures of visceral fat volume in HATIM (all P<0.05). Further, 2-AAA associated with increased liver fat in persons with HIV (P<0.001). Our study confirms 2-AAA as a marker of cardiometabolic risk in both healthy individuals and those at high cardiometabolic risk, reveals relationships with adiposity and hepatic steatosis, and highlights important differences by sex and race. Further studies are warranted to establish molecular mechanisms linking 2-AAA to disease in other high-risk populations.

Aerobic and Muscle-Strengthening Physical Activity, Television Viewing, and Nonalcoholic Fatty Liver Disease: The CARDIA Study

BACKGROUND

The prevalence of non-alcoholic fatty liver disease (NAFLD) in U.S. adults is over 30%, yet the role of lifestyle factors in the etiology of NAFLD remains understudied. We examined the associations of physical activity, by intensity and type, and television viewing with prevalent NAFLD.

METHODS

Cross-sectional analysis of a population-based sample of 2726 Black (49%) and White (51%) adults (Mean (SD) age, 50 (3.6) years; 57.3% female) from the CARDIA study. Exposures were aerobic activity by intensity (moderate, vigorous; hours/week); activity type (aerobic, muscle-strengthening; hours/week); and television viewing (hours/week), examined concurrently in all models and assessed by validated questionnaires. Our outcome was NAFLD (liver attenuation < 51 Hounsfield Units), measured by non-contrast computed tomography, after exclusions for other causes of liver fat. Covariates were sex, age, race, study center, education, diet quality, smoking status, alcohol consumption, and body mass index or waist circumference.

RESULTS

648 participants had NAFLD. In the fully adjusted modified Poisson regression model, the risk ratios per interquartile range of each exposure were moderate-intensity aerobic activity, 1.10 (95% CI, 0.97-1.26); vigorous-intensity aerobic activity, 0.72 (0.63-0.82); muscle-strengthening activity, 0.89 (0.80-1.01); and television viewing, 1.20 (1.10-1.32). Relative to less active participants with higher levels of television viewing, those who participated in ≥2 h/week of both vigorous-intensity aerobic and muscle-strengthening activity and <7 h/week of television viewing had 65% lower risk of NAFLD (risk ratio = 0.35, 95% CI = 0.23-0.51).

CONCLUSION

Adults who follow public health recommendations for vigorous-aerobic and muscle-strengthening activity, as well as minimize television viewing, are considerably less likely to have NAFLD than those who do not follow the recommendations and who have relatively high levels of television viewing.

AI Body Composition in Lung Cancer Screening: Added Value Beyond Lung Cancer Detection

Background An artificial intelligence (AI) algorithm has been developed for fully automated body composition assessment of lung cancer screening noncontrast low-dose CT of the chest (LDCT) scans, but the utility of these measurements in disease risk prediction models has not been assessed. Purpose To evaluate the added value of CT-based AI-derived body composition measurements in risk prediction of lung cancer incidence, lung cancer death, cardiovascular disease (CVD) death, and all-cause mortality in the National Lung Screening Trial (NLST). Materials and Methods In this secondary analysis of the NLST, body composition measurements, including area and attenuation attributes of skeletal muscle and subcutaneous adipose tissue, were derived from baseline LDCT examinations by using a previously developed AI algorithm. The added value of these measurements was assessed with sex- and cause-specific Cox proportional hazards models with and without the AI-derived body composition measurements for predicting lung cancer incidence, lung cancer death, CVD death, and all-cause mortality. Models were adjusted for confounding variables including age; body mass index; quantitative emphysema; coronary artery calcification; history of diabetes, heart disease, hypertension, and stroke; and other PLCO_M2012 lung cancer risk factors. Goodness-of-fit improvements were assessed with the likelihood ratio test. Results Among 20 768 included participants (median age, 61 years [IQR, 57-65 years]; 12 317 men), 865 were diagnosed with lung cancer and 4180 died during follow-up. Including the AI-derived body composition measurements improved risk prediction for lung cancer death (male participants: χ² = 23.09, P < .001; female participants: χ² = 15.04, P = .002), CVD death (males: χ² = 69.94, P < .001; females: χ² = 16.60, P < .001), and all-cause mortality (males: χ² = 248.13, P < .001; females: χ² = 94.54, P < .001), but not for lung cancer incidence (male participants: χ² = 2.53, P = .11; female participants: χ² = 1.73, P = .19). Conclusion The body composition measurements automatically derived from baseline low-dose CT examinations added predictive value for lung cancer death, CVD death, and all-cause death, but not for lung cancer incidence in the NLST. Clinical trial registration no. NCT00047385 © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Fintelmann in this issue.

Association of alpha-aminoadipic acid (2-AAA) with cardiometabolic risk factors in healthy and high-risk individuals

Plasma levels of the metabolite alpha-aminoadipic acid (2-AAA) have been associated with risk of type 2 diabetes (T2D) and atherosclerosis. However, little is known about the relationship of 2-AAA to other cardiometabolic risk markers in pre-disease states, or in the setting of comorbid disease. We measured circulating 2-AAA using two methods in 1) a sample of 261 healthy individuals (2-AAA Study), and 2) in a sample of 134 persons comprising 110 individuals with treated HIV, with or without T2D, a population at high risk of metabolic disease and cardiovascular events despite suppression of circulating virus, and 24 individuals with T2D without HIV (HATIM Study). We examined associations between plasma 2-AAA and markers of cardiometabolic health within each cohort. We observed differences in 2-AAA by sex and race in both cohorts, with higher levels observed in men compared with women, and in Asian compared with Black or white individuals (P<0.05). There was no significant difference in 2-AAA by HIV status within individuals with T2D in the HATIM Study. We confirmed associations between 2-AAA and dyslipidemia in both cohorts where high 2-AAA associated with low HDL cholesterol (P<0.001) and high triglycerides (P<0.05). As expected, within the cohort of people with HIV, 2-AAA was higher in the setting of T2D compared to pre-diabetes or normoglycemia (P<0.001). 2-AAA was positively associated with body mass index (BMI) in the 2-AAA Study, and with waist circumference and measures of visceral fat volume in HATIM (all P<0.05). Further, 2-AAA associated with increased liver fat in persons with HIV (P<0.001). Our study confirms 2-AAA as a marker of cardiometabolic risk in both healthy individuals and those at high cardiometabolic risk, reveals relationships with adiposity and hepatic steatosis, and highlights important differences by sex and race. Further studies are warranted to establish molecular mechanisms linking 2-AAA to disease in other high-risk populations.

The association between hepatic steatosis and incident cardiovascular disease, cancer, and all-cause mortality in a US multicohort study

BACKGROUND AND AIMS

NAFLD strongly associates with cardiovascular disease (CVD) risk factors; however, the association between NAFLD and incident CVD, CVD-related mortality, incident cancer, and all-cause mortality is unclear.

APPROACH AND RESULTS

We included 10,040 participants from the Framingham Heart Study, the Coronary Artery Risk Development in Young Adults Study, and the Multi-ethnic Study of Atherosclerosis to assess the longitudinal association between liver fat (defined on CT) and incident CVD, CVD-related mortality, incident cancer, and all-cause mortality. We performed multivariable-adjusted Cox regression models including age, sex, diabetes, systolic blood pressure, alcohol use, smoking, HDL, triglycerides, and body mass index at baseline or time-varying covariates. The average age was 51.3±3.3 years and 50.6% were women. Hepatic steatosis was associated with all-cause mortality after 12.7 years of mean follow-up when adjusting for baseline CVD risk factors, including body mass index (HR: 1.21, 1.04-1.40); however, the results were attenuated when utilizing time-varying covariates. The association between hepatic steatosis and incident CVD was not statistically significant after we accounted for body mass index in models considering baseline covariates or time-varying covariates. We observed no association between hepatic steatosis and CVD-related mortality or incident cancer.

CONCLUSIONS

In this large, multicohort study of participants with CT-defined hepatic steatosis, accounting for change in CVD risk factors over time attenuated associations between liver fat and overall mortality or incident CVD. Our work highlights the need to consider concurrent cardiometabolic disease when determining associations between NAFLD and CVD and mortality outcomes.

Enlarged perivascular space burden associations with arterial stiffness and cognition

Enlarged perivascular spaces (ePVS) are difficult to quantify, and their etiologies and consequences are poorly understood. Vanderbilt Memory and Aging Project participants (n = 327, 73 ± 7 years) completed 3T brain MRI to quantify ePVS volume and count, longitudinal neuropsychological assessment, and cardiac MRI to quantify aortic stiffness. Linear regressions related (1) PWV to ePVS burden and (2) ePVS burden to cross-sectional and longitudinal neuropsychological performance adjusting for key demographic and medical factors. Higher aortic stiffness related to greater basal ganglia ePVS volume (β = 7.0×10-5, p = 0.04). Higher baseline ePVS volume was associated with worse baseline information processing (β = -974, p = 0.003), executive function (β = -81.9, p < 0.001), and visuospatial performances (β = -192, p = 0.02) and worse longitudinal language (β = -54.9, p = 0.05), information processing (β = -147, p = 0.03), executive function (β = -10.9, p = 0.03), and episodic memory performances (β = -10.6, p = 0.02). Results were similar for ePVS count. Greater arterial stiffness relates to worse basal ganglia ePVS burden, suggesting cardiovascular aging as an etiology. ePVS burden is associated with adverse cognitive trajectory, emphasizing the clinical relevance of ePVS.

Thigh and Calf Myosteatosis are Strongly Associated with Muscle and Physical Function in African Caribbean Men

BACKGROUND

African Caribbeans have higher levels of myosteatosis than other populations; however, little is known about the impact of myosteatosis on physical function in African Caribbeans. Herein, we examined the association between regional myosteatosis of the calf, thigh, and abdomen versus physical function in 850 African-Ancestry men aged 64.2 ± 8.9 (range 50-95) living on the Caribbean Island of Tobago.

METHODS

Myosteatosis was measured using computed tomography and included intermuscular adipose tissue (IMAT) and muscle density levels of the thigh, calf, psoas, and paraspinous muscles. Outcomes included grip strength, time to complete 5 chair-rises, and 4-meter gait speed. Associations were quantified using separate linear models for each myosteatosis depot and were adjusted for age, height, demographics, physical activity, and chronic diseases. Beta coefficients were presented per standard deviation of each myosteatosis depot.

RESULTS

Higher thigh IMAT was the only IMAT depot significantly associated with weaker grip strength (β = -1.3 ± 0.43 kg, p = .003). However, lower muscle density of all 4 muscle groups was associated with weaker grip strength (all p < .05). Calf and thigh myosteatosis (IMAT and muscle density) were significantly associated with both worse chair rise time and gait speed (all p < .05), whereas psoas IMAT and paraspinous muscle density were associated with gait speed.

CONCLUSION

Myosteatosis of the calf and thigh-but not the abdomen-were strongly associated with grip strength and performance measures of physical function in African Caribbean men. However, posterior abdominal myosteatosis may have some utility when abdominal images are all that are available.

Abstract MP34: Non-Alcoholic Fatty Liver Disease Modifies the Associations of Body Mass Index and Waist Circumference With Changes in Cardiometabolic Risk: The Cardia Study

Introduction: Non-alcoholic fatty liver disease (NAFLD) is often unrecognized and untreated despite its high prevalence (~25% of adults) and implications for cardiometabolic diseases. We examined the potential for NAFLD to modify the associations between BMI and waist circumference (WC) with changes in cardiometabolic risk.

Hypothesis: The associations of BMI and WC with CMR risk are modified by NAFLD.

Methods: We analyzed data from Years 25 (2010/11) and 30 (2015/6) of the CARDIA cohort. NAFLD status was determined by noncontrast CT with a liver attenuation cut-off <51 HU after exclusions for other causes of liver fat. The outcome was 5-yr change in cardiometabolic risk score (CMR) derived by the mean Z-score score of fasting glucose, insulin, triglycerides [log], (-)HDL cholesterol, and systolic blood pressure. BMI and WC were directly assessed, and covariates included age, sex, race, center, education, smoking, alcohol, and medications for diabetes or CVD, and Year 25 CMR. Multivariable linear regression models included NAFLD status, BMI, and WC as the independent variables. Effect modification was assessed by interaction terms between NAFLD and continuous BMI and WC in separate models. Subsequent models were stratified by NAFLD status.

Results: Our final sample size was 2366 (mean age: 50.1 y, males: 42.6%, Black race: 47.2%) with a NAFLD prevalence of 23% (n=539). Year 25 mean (± sd) CMR for those with and without NAFLD was -0.21 ± 0.58 and 0.50 ± 0.60, respectively. NAFLD status considerably modified the association of both BMI (interaction p<0.001) and WC (interaction p=0.002) with CMR change. BMI and WC were more strongly associated with CMR in participants without NAFLD compared to those with NAFLD (see Table). Within each BMI and WC category, CMR change was higher for those with NAFLD relative to those without NAFLD.

Conclusion: NAFLD status modifies the association between BMI and WC with CMR changes. These findings have implications for routine clinical screening guidelines and risk stratification.

Abstract P226: Aerobic and Muscle Strengthening Physical Activity and Television Viewing Are Independently Associated With Odds of Nonalcoholic Fatty Liver Disease: The Cardia Study

Introduction: The prevalence of nonalcoholic fatty liver disease (NAFLD) in US adults is over 25%, yet the etiology of lifestyle factors in the development of NAFLD remains understudied. We examined the independent and joint associations among aerobic physical activity (PA) intensity (moderate, vigorous) and PA type (aerobic, muscle strengthening), television viewing (TV), and odds of NAFLD.

Hypothesis: Higher levels of aerobic and muscle strengthening PA are associated with lower odds of NAFLD, and higher levels of TV are associated with higher odds of NAFLD.

Methods: We analyzed data from Year 25 of the CARDIA cohort study. Our exposures (moderate and vigorous aerobic and muscle strengthening PA, TV; hr/wk) were assessed using validated questionnaires. Our outcome (NAFLD) was measured using non-contrast computed tomography. We constructed multivariable logistic regression models to examine the independent and joint associations between PA (moderate or vigorous aerobic and strength), TV, and odds of NAFLD. Covariates were sex, age, race, study center, education, diet, smoking status, alcohol consumption, and waist circumference.

Results: 2726 participants (648 with NAFLD) were analyzed (mean (SD) age, 50.1 (3.6) years; 49% Black; 43% male). Fully adjusted odds ratios per IQR-standardized continuous PA and TV were: moderate aerobic PA (IQR = 4.3), 0.93 (95% CI, 0.81-1.07); vigorous aerobic PA (IQR = 1.9), 0.63 (95% CI, 0.55-0.73); muscle strengthening PA (IQR = 3.3), 0.80 (95% CI, 0.07-0.92); and TV (IQR = 14.0), 1.20 (95% CI, 1.10-1.32). Only vigorous aerobic PA remained statistically significant after waist circumference adjustment, 0.83 (95% CI, 0.70-0.98). A PA-TV index model (Figure) indicated the combination of higher vigorous aerobic and muscle strengthening PA and lower TV resulted in an odds ratio of 0.23 (95% CI, 0.15-0.37).

Conclusion: Concurrent higher levels of vigorous aerobic PA (≥2 hr/wk), muscle strengthening PA (≥2 hr/wk), and lower levels of TV (<7 hr/wk) were associated with 77% lower odds of NAFLD.

Abstract MP71: Associations Between Physical Activity Trajectories and Nonalcoholic Fatty Liver Disease: The Cardia Study

Introduction: Non-alcoholic fatty liver disease (NAFLD) is one of the most common causes of chronic liver disease in the US. Weight loss and lifestyle modifications, including increases in physical activity (PA), are the primary therapeutic recommendations for managing NAFLD. However, little is known about longitudinal physical activity patterns and NAFLD prevalence among a racially diverse population of adults. This study aimed to (1) identify distinct physical activity trajectories from young to middle adulthood and (2) examine the associations between physical activity trajectories and NAFLD prevalence in middle-aged adults.

Methods: The analytic sample included 2833 participants of the Coronary Artery Risk Development in Young Adults (CARDIA) study. Physical activity was self-reported at eight examinations over 25 years (1985/1986 to 2010/2011), and separately scored for moderate- (MPA) and vigorous-intensity (VPA) physical activity. NAFLD was defined as liver attenuation values ≤51 Hounsfield units after exclusion of other causes of liver fat, measured using computed tomography in year 25 (2010/2011). Group-based trajectory modeling was used to identify MPA and VPA trajectories over 25 years. Modified Poisson regression models were used to estimate the risk ratios (RR) of NAFLD across the PA trajectories, adjusted for year 25 sex, age, CARDIA study center, race, education, smoking status, dietary pattern, and alcohol consumption.

Results: We identified three distinct MPA and VPA trajectories. MPA: ‘very low stable’ (53%), ‘low stable’ (39%), and ‘moderate increasing’ (8%). VPA: ‘low stable’ (57%), ‘moderate stable’ (36%), and ‘high decreasing’ (7%). Year 25 NAFLD prevalence was 24%. Relative to participants with ‘moderate increasing’ MPA over time, those with lower levels of MPA had adjusted risk ratios of 1.11 (95% CI 0.87-1.43) for ‘low stable’ and 1.11 (95% CI 0.86-1.42) for ‘very low stable.’ Relative to participants with ‘high decreasing’ VPA over time, those with lower levels of VPA had adjusted risk ratios of 1.26 (95% CI 0.95-1.69) for ‘moderate stable’ and 1.62 (95% CI 1.21-2.16) for ‘low stable.’

Conclusions: Our results suggest a higher risk of NAFLD in middle age for those with low levels of VPA from young to middle adulthood relative to those with the highest levels of VPA over time, with evidence of dose-response. Sustaining VPA throughout adulthood may be efficacious in the prevention of NAFLD, highlighting the importance of targeted delivery of prevention and management programs aimed at modifying lifestyle risk factors to reduce NAFLD risk.

Abstract P664: Proteomic Profiling of African-Ancestry Adults Identifies Potential Novel Biomarkers of Vascular Aging

During the aging process, the vasculature undergoes pathologic changes which are strongly associated with hypertension and future cardiovascular disease (CVD) risk. Previous work to identify protein biomarkers of these subclinical vascular changes, which have largely focused on single proteins, has observed many associations in different populations. However, research in African-ancestry populations, who are at high risk for hypertensive CVD, is limited and may be biased by the existing research in Whites. Therefore, we used a proteomic approach to identify biomarkers of vascular aging as assessed by pulse-wave velocity (PWV) and abdominal aortic calcification (AAC). We included 346 African-ancestry men from the Tobago Health Study, a prospective cohort study of community-dwelling men aged ≥40 years residing on the Caribbean island of Tobago. These men were aged from 53-89 years old (mean ± SD = 63.4 ± 8.1 years) and were overweight on average (mean ± SD BMI = 27.7 ± 4.3kg/m2). 79.2% of men had hypertension, 24.6% had diabetes, and 5.9% were current smokers. We quantified protein expression using the Olink® Target 96 Cardiovascular III proteomics panel which includes 92 proteins with known association to human cardiovascular processes (CVDIII; Olink®, Waltham, MA). Brachial-ankle PWV (cm/s) was measured using an automated waveform analyzer. AAC was measured in the aorta at the iliac bifurcation via CT and scored using the Agatston method. Partial Spearman correlations were calculated to assess the relationship between each protein biomarker and both vascular aging outcomes adjusting for age, Olink® assay batch, height, weight, diabetes status, hypertension status, and current smoking. There were 13 and 5 proteins correlated with PWV and AAC, respectively (at P<0.05). All correlations were in the direct direction of effect. Only one protein, cystatin B, was correlated with both PWV and AAC (r= 0.17 and 0.12, P=0.002 and 0.03; respectively). After applying false discovery rate adjustment for multiple comparisons, only fatty acid binding protein 4 (FABP4) and PWV remained significant (r=0.18, P=0.046). In general, proteins categorized by Olink® as belonging to the inflammatory pathway were most likely to be correlated with PWV; whereas, those in the hormone response pathway were most frequently correlated with AAC. Our results highlight that FABP4, a protein related to atherosclerosis via inflammation, may also be an important marker of arterial stiffening in these African-ancestry men. Additionally, we identified cystatin B, a member of the cathepsin protease pathway, as a strong correlate of both PWV and AAC, which may warrant further research into it as a novel biomarker of vascular aging and CVD in this high-risk population. In conclusion, proteomics may be an effective tool for evaluating and identifying novel markers of vascular aging and CVD in underrepresented populations.

Improved bias and reproducibility of coronary artery calcification features using deconvolution

Purpose

Our long-range goal is to improve whole-heart CT calcium scores by extracting quantitative features from individual calcifications. Here, we perform deconvolution to improve bias/reproducibility of small calcification assessments, which can be degraded at the normal CT calcium score image resolution.

Approach

We analyzed features of individual calcifications on repeated standard (2.5 mm) and thin (1.25 mm) slice scans from QRM-Cardio phantom, cadaver hearts, and CARDIA study participants. Preprocessing to improve the resolution involved of Lucy-Richardson deconvolution with a measured point spread function (PSF) or three-dimensional blind deconvolution in which the PSF was iteratively optimized on high detail structures such as calcifications in images.

Results

Using QRM with inserts having known mg-calcium, we determined that both blind and conventional deconvolution improved mass measurements nearly equally well on standard images. Further, deconvolved thin images gave an excellent recovery of actual mass scores, suggesting that such processing could be our gold standard. For CARDIA images, blind deconvolution greatly improved results on standard slices. Bias across 33 calcifications (without, with deconvolution) was (23%, 9%), (18%, 1%), and ( - 19 % , - 1 % ) for Agatston, volume, and mass scores, respectively. Reproducibility was (0.13, 0.10), (0.12, 0.08), and (0.11, 0.06), respectively. Mass scores were more reproducible than Agatston scores or volume scores. For many other calcification features, blind deconvolution improved reproducibility in 21 out of 24 features. Cadaver images showed similar improvements in bias/reproducibility and slightly better results with a measured PSF.

Conclusions

Deconvolution improves bias and reproducibility of multiple features extracted from individual calcifications in CT calcium score exams. Blind deconvolution is useful for improving feature assessments of coronary calcification in archived datasets.

Mean Coronary Cross-Sectional Area as a Measure of Arterial Remodeling Using Noncontrast CT Imaging in Persons With HIV

Background Persons with HIV have a higher prevalence of coronary artery disease compared with their HIV-negative counterparts. Earlier identification of subclinical atherosclerosis may provide a greater opportunity for cardiovascular disease risk reduction. We investigated coronary cross-sectional area (CorCSA) by noncontrasted computed tomography imaging as a noninvasive measure of arterial remodeling among virally suppressed persons with HIV. Methods and Results We assessed 105 persons with HIV with a spectrum of cardiometabolic health. All participants underwent computed tomography imaging to assess the mean corCSA of the proximal left anterior descending artery and 28 participants underwent additional coronary computed tomography angiography. Partial Spearman rank correlations adjusted for cardiovascular disease risk factors were used to assess relationships of corCSA with anthropometric measurements, HIV-related factors, and plasma cytokines. Mean corCSA measured by noncontrast computed tomography and coronary computed tomography angiography were strongly correlated (ρ=0.91, P<0.0001). Higher mean corCSA was present in those with coronary artery calcium (P=0.005) and it correlated with participants' atherosclerotic cardiovascular disease risk score (ρ=0.35, P=0.01). After adjusting for established cardiovascular disease risk factors, we observed an inverse relationship between corCSA and CD4+ T-cell count (ρ=-0.2, P=0.047). Removal of age from the model strengthened the relationships between corCSA and antiretroviral therapy duration (from ρ=0.19, P=0.08 to ρ=0.3, P=0.01). CorCSA was also inversely correlated with plasma IL-10 (ρ=-0.25, P=0.03) but had no relationship with IL-6 (ρ=0.11, P=0.4) or IL-1β (ρ=0.08, P=0.5). Conclusions Positive coronary arterial remodeling, an imaging marker of subclinical atherosclerosis, is associated with a lower CD4 T-cell count, lower circulating IL-10, and possibly a longer antiretroviral therapy duration in persons with HIV. Registration Clinicaltrials.gov; Unique identifier: NCT04451980.

Long-term association of pericardial adipose tissue with incident diabetes and prediabetes: the Coronary Artery Risk Development in Young Adults Study

OBJECTIVES

We examined whether pericardial adipose tissue (PAT) is predictive of prediabetes and type 2 diabetes over time.

METHODS

In total, 2,570 adults without prediabetes/diabetes from the Coronary Artery Risk Development in Young Adults Study were followed up over 15 years. PAT volume was measured by computed tomography scans, and the new onset of prediabetes/diabetes was examined 5 years, 10 years, and 15 years after the PAT measurements. Multivariable Cox regression models were used to examine the association between the tertile of PAT and incident prediabetes/diabetes up to 15 years later. The predictive ability of PAT (vs. waist circumference [WC], body mass index [BMI], waist-to-height ratio [WHtR]) for prediabetes/diabetes was examined by comparing the area under the receiver operating characteristic curve (AUC).

RESULTS

The highest tertile of PAT was associated with a 1.56 times (95% confidence interval [CI], 1.03 to 2.34) higher rate of diabetes than the lowest tertile; however, no association was found between the highest tertile of PAT and prediabetes in the fully adjusted models, including additional adjustment for BMI or WC. In the fully adjusted models, the AUCs of WC, BMI, WHtR, and PAT for predicting diabetes were not significantly different, whereas the AUC of WC for predicting prediabetes was higher than that of PAT.

CONCLUSIONS

PAT may be a significant predictor of hyperglycemia, but this association might depend on the effect of BMI or WC. Additional work is warranted to examine whether novel adiposity indicators can suggest advanced and optimal information to supplement the established diagnosis for prediabetes/diabetes.

Replacing sedentary time with light activity was associated with less adiposity across several depots in African ancestry men

OBJECTIVE

The aim of this study was to determine whether displacement of sedentary time with activity was cross-sectionally associated with less adiposity among Black Caribbean men in the Tobago Health Study.

METHODS

Objectively assessed activity was categorized as sedentary (< 1.5 metabolic equivalents; METs), light (≥ 1.5 to < 3.0 METs), or moderate-to-vigorous (≥ 3.0 METs) using the SenseWear Pro armband. Computed tomography scans of the chest, abdomen, liver, and thigh were used to assess subcutaneous and ectopic adipose tissue. The isotemporal substitution framework paired with linear regression was used to examine associations between activity and adiposity adjusting for age, height, total awake time, and multiple comparisons.

RESULTS

On average, participants (n = 271) were 63 years old with 11.2 h/d of sedentary behavior, 4.5 h/d of light activity, and 54 min/d of moderate-to-vigorous activity. Replacing sedentary time with light activity was cross-sectionally associated with lower volume and higher density of abdominal and thigh subcutaneous adiposity, visceral adiposity, abdominal and thigh intermuscular adiposity, and pericardial adiposity and higher liver attenuation (p values ≤ 0.0001).

CONCLUSIONS

Displacement of sedentary time with light activity was associated with less adiposity among this Black Caribbean cohort. Interventions focused on increasing light activity may be easier to maintain than higher intensity interventions and thus may be more successful at reducing adiposity.

Antimüllerian hormone and leukocyte aging markers in the Coronary Artery Risk Development in Young Adults study

OBJECTIVE

To examine whether premenopausal reproductive age, as indicated by serum antimüllerian hormone (AMH), is associated with leukocyte aging biomarkers.

DESIGN

Prospective cohort analysis.

SETTING

The Coronary Artery Risk Development in Young Adults study, a population-based study of Black and White adults from four US communities (Birmingham, AL; Chicago, IL; Minneapolis, MN; Oakland, CA).

PATIENT(S)

Premenopausal women with serum AMH measures at examination year 15 as well as leukocyte aging markers.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Telomere length, mitochondrial deoxyribonucleic acid (mtDNA) copy number, and intrinsic and extrinsic epigenetic age acceleration (EAA) at examination years 15, 20, and 25 as well as change between examination years.

RESULT(S)

Women were 40.2 (standard deviation, 3.7) years of age at examination year 15 when the AMH and initial measures of telomere length and mtDNA copy number (n = 386) were obtained and EAA occurred. After adjustment for chronological age, race, and smoking history, AMH quartile at examination year 15 was not associated with telomere length at examination years 15 and 25 or telomere length change between these years, mtDNA copy number at examination years 15 and 25 or change between these years, or intrinsic EAA at examination years 15 and 20 or change between these years. Women in the second AMH quartile had faster extrinsic EAA than women in the lowest AMH quartile (β-coefficient, 1.84; 95% confidence interval, 0.20-3.49).

CONCLUSION(S)

In a population-based cohort, AMH did not have associations with leukocyte telomere length, mtDNA copy number, or intrinsic EAA.

Relationship of Subcutaneous Adipose Tissue Inflammation-Related Gene Expression With Ectopic Lipid Deposition in Persons With HIV

OBJECTIVE

Fat redistribution from subcutaneous adipose tissue (SAT) to the abdominal viscera, pericardium, liver, and skeletal muscle contributes to the rising burden of cardiometabolic disease among persons with HIV (PWH). Previous studies found SAT inflammation in PWH impairs lipid storage and persists despite plasma viral suppression on antiretroviral therapy (ART). In this study, we identified SAT immune-related genes associated with ectopic fat deposition in PWH on long-term ART.

DESIGN AND METHODS

A total of 92 PWH with well-controlled viremia underwent computed tomography imaging and abdominal SAT biopsy for gene expression analysis. SAT gene expression was measured using a NanoString panel of 255 immune-related genes. Associations between gene expression and computed tomography measurements of the volume and attenuation (radiodensity) of metabolically relevant ectopic fat depots were assessed using multivariable linear regression and network analysis.

RESULTS

Greater SAT volume was associated with higher visceral and pericardial adipose tissue volume, but lower skeletal muscle attenuation. Lower SAT attenuation, a measure of lipid content, was associated with lower visceral adipose tissue attenuation. Hierarchical clustering identified a subset of macrophage-related genes in SAT, including CCL2, CCL22, CCL13, CCR1, CD86, CD163, IL-6, IL-10, MRC1, and TREM2, which were associated with an increased lipid deposition in multiple ectopic depots.

CONCLUSION

Altered expression of macrophage-related genes in SAT is associated with differences in ectopic fat depot morphometrics among PWH on long-term ART, including in the pericardial and visceral compartments. These findings provide basis for future studies to assess host, virus, and treatment factors shaping the SAT immune environment and its effects on morphometric changes and metabolic comorbidities in PWH.

Cardiorespiratory Fitness in Adults Aged 18 to 34 Years and Long-Term Pericardial Adipose Tissue (from the Coronary Artery Risk Development in Young Adults Study)

Pericardial adipose tissue (PAT), an ectopic adipose depot surrounding the coronary arteries, is a pathogenic risk marker for cardiometabolic disease; however, the association between cardiorespiratory fitness (CRF) and PAT is unclear. Young adults (n = 2,614, mean age 25.1 years, 55.8% women, and 43.8% Black at baseline [1985 to 1986]) from the Coronary Artery Risk Development in Young Adults study were included. Maximal CRF was estimated at baseline, examination year 7 (1992 to 1993) and year 20 (2005 to 2006), using a symptom-limited maximal treadmill exercise test (duration in minutes) among those achieving ≥85% of age-predicted maximal heart rate. PAT volume (ml) was quantified at examination year 15 (2000 to 2001) and year 25 (2010 to 2011) using computed tomography. Multivariable linear and linear mixed regressions with covariates (sociodemographics, cardiovascular disease risk factors, inflammation, waist circumference) from baseline, year 7, and/or year 20 were used. Separate multivariable regression models revealed inverse associations of CRF at baseline, year 7, or year 20 with PAT at year 25 in fully adjusted models (all p <0.001). The linear mixed model showed that a 1-minute increase in treadmill exercise test duration over 20 years was associated with 1.49 ml lower subsequent PAT volume (p <0.001). In conclusion, findings suggest that higher CRF is inversely associated with subsequent PAT volume. Strategies to optimize CRF may be preventive against excessive PAT accumulation with age.

Aortic Area as an Indicator of Subclinical Cardiovascular Disease

Aim:

Outward arterial remodeling occurs early in cardiovascular disease (CVD) and, as such, measuring arterial dimension may be an early indicator of subclinical disease.

Objective:

The objective of our study was to measure area at three aortic locations: The ascending thoracic (ASC), the descending thoracic (DSC), and the abdominal (ABD), and to test for association with traditional CVD risk factors and subclinical CVD throughout the body.

Methods:

We measured ASC, DSC, and ABD using computed tomography (CT) in 408 African ancestry men aged 50-89 years. We assessed prevalent CVD risk factors via participant interview and clinical exam, and subclinical CVD, including carotid atherosclerosis through B-mode carotid ultrasound, vascular calcification via chest and abdominal CT, and arterial stiffness via pulse-wave velocity (PWV).

Results:

As expected, all aortic areas were in correlation with each other (r=0.39-0.63, all p<0.0001) and associated with greater age, greater body size, and hypertension (p≤0.01 for all). After adjustment for traditional CVD risk factors, ASC was positively associated with carotid atherosclerosis (p<0.01). A greater area at each location was associated with greater PWV (p<0.03 for all), with the DSC region showing the most significant association.

Conclusion:

This is the first study to test the association of aortic area measured at multiple points with subclinical CVD. We found that combined CT assessment of ascending and descending aortic area may indicate a high risk of prevalent subclinical CVD elsewhere in the body independent of age, body size, and blood pressure.

Axonal Injury Partially Mediates Associations Between Increased Left Ventricular Mass Index and White Matter Damage

BACKGROUND AND PURPOSE

Left ventricular (LV) mass index is a marker of subclinical LV remodeling that relates to white matter damage in aging, but molecular pathways underlying this association are unknown. This study assessed if LV mass index related to cerebrospinal fluid (CSF) biomarkers of microglial activation (sTREM2 [soluble triggering receptor expressed on myeloid cells 2]), axonal injury (NFL [neurofilament light]), neurodegeneration (total-tau), and amyloid-β, and whether these biomarkers partially accounted for associations between increased LV mass index and white matter damage. We hypothesized higher LV mass index would relate to greater CSF biomarker levels, and these pathologies would partially mediate associations with cerebral white matter microstructure.

METHODS

Vanderbilt Memory and Aging Project participants who underwent cardiac magnetic resonance, lumbar puncture, and diffusion tensor imaging (n=142, 72±6 years, 37% mild cognitive impairment [MCI], 32% APOE-ε4 positive, LV mass index 51.4±8.1 g/m², NFL 1070±588 pg/mL) were included. Linear regressions and voxel-wise analyses related LV mass index to each biomarker and diffusion tensor imaging metrics, respectively. Follow-up models assessed interactions with MCI and APOE-ε4. In models where LV mass index significantly related to a biomarker and white matter microstructure, we assessed if the biomarker mediated white matter associations.

RESULTS

Among all participants, LV mass index was unrelated to CSF biomarkers (P>0.33). LV mass index interacted with MCI (P=0.01), such that higher LV mass index related to increased NFL among MCI participants. Associations were also present among APOE-ε4 carriers (P=0.02). NFL partially mediated up to 13% of the effect of increased LV mass index on white matter damage.

CONCLUSIONS

Subclinical cardiovascular remodeling, measured as an increase in LV mass index, is associated with neuroaxonal degeneration among individuals with MCI and APOE-ε4. Neuroaxonal degeneration partially reflects associations between higher LV mass index and white matter damage. Findings highlight neuroaxonal degeneration, rather than amyloidosis or microglia, may be more relevant in pathways between structural cardiovascular remodeling and white matter damage.

Dietary Patterns and Prevalent NAFLD at Year 25 from the Coronary Artery Risk Development in Young Adults (CARDIA) Study

The prevalence of nonalcoholic fatty liver disease is rapidly rising. We aimed to investigate associations of diet quality and dietary patterns with nonalcoholic fatty liver disease (NAFLD) in Black and White adults. We included 1726 participants who attended the Year 20 Exam of the Coronary Artery Risk Development in Young Adults (CARDIA) study and had their liver attenuation (LA) measured using computed tomography at Year 25 (2010–2011). NAFLD was defined as an LA of ≤51 Hounsfield units after the exclusion of other causes of liver fat. The a priori diet-quality score (APDQS) was used to assess diet quality, and dietary patterns were derived from principal components analysis. Univariate and multivariable logistic regression models were used to evaluate the association between the APDQS, dietary patterns, and NAFLD, and were adjusted for Year 20 covariates. NAFLD prevalence at Year 25 was 23.6%. In a model adjusted for age, race, sex, education, alcohol use, physical activity, smoking, and center at Year 25, the APDQS was inversely associated (p = 0.004) and meat dietary pattern was positively associated (p < 0.0001) with NAFLD, while the fruit-vegetable dietary pattern was not significantly associated (p = 0.40). These associations remained significant when additionally adjusting for comorbidities (type 2 diabetes mellitus, dyslipidemia, hypertension), however, significant associations were diminished after additionally adjusting for body mass index (BMI). Overall, this study finds that the APDQS and meat dietary patterns are associated with prevalent NAFLD in mid-life. The associations appear to be partially mediated through higher BMI.

Exposure to Neighborhood-Level Racial Residential Segregation in Young Adulthood to Midlife and Incident Subclinical Atherosclerosis in Black Adults: The Coronary Artery Risk Development in Young Adults Study

BACKGROUND

Neighborhood-level racial residential segregation has been linked to several cardiovascular disease risk factors and outcomes in Black adults, but its impact on subclinical atherosclerosis remains unknown. In addition, although the impact of segregation on health may vary over the life course, most studies have examined segregation exposure at a single point in time. This article takes a life course approach by examining associations of exposure to neighborhood-level racial residential segregation in young adulthood and patterns of exposure from young adulthood to midlife with coronary artery calcification (CAC) incidence.

METHODS

We used data on 1125 Black CARDIA study (Coronary Artery Risk Development in Young Adults) participants free of CAC. Residential segregation was assessed using the Gi* statistic and measured when participants were young adults (18-30 years old, in 1985-1986) and as the pattern from young adulthood to midlife (15 years later). Poisson regression with generalized estimating equations models was used to measure CAC incidence.

RESULTS

We found participants living in low segregation neighborhoods in young adulthood had 0.52 (rate ratio [95% CI: 0.28-0.98]) times lower risk of developing CAC compared with high segregation after adjusting for young adulthood sociodemographic characteristics and neighborhood poverty. Associations were attenuated and no longer statistically significant with adjustment for midlife CAC risk factors hypothesized to be on the causal pathway (rate ratio: 0.56 [95% CI: 0.29-1.09]). Findings for patterns of segregation over time suggest participants living in low segregation neighborhoods in young adulthood were less likely to develop CAC than those who started out in medium/high segregation neighborhoods, regardless of where they lived in midlife (rate ratio for increase from low to medium/high: 0.42 [95% CI: 0.19-0.95]; rate ratio for continuously low versus continuously medium/high segregation neighborhoods: 0.75 [95% CI: 0.31-1.83]).

CONCLUSIONS

We found that participants living in more segregated neighborhoods in young adulthood were more likely to develop CAC due at least in part to differences in CAC risk factor burden accumulated over follow-up.

Association of Abdominal Aorta Calcium and Coronary Artery Calcium with Incident Cardiovascular and Coronary Heart Disease Events in Black and White Middle-Aged People: The Coronary Artery Risk Development in Young Adults Study

Background Assessing coronary artery calcium (CAC) is among AHA/ACC prevention guidelines for people at least 40 years old at intermediate risk for coronary heart disease (CHD). To study enhanced risk stratification, we investigated the predictive value of abdominal aorta calcium (AAC) relative to CAC for cardiovascular disease (CVD) and CHD events in Black and White early middle-aged participants, initially free of overt CVD. Methods and Results In the CARDIA (Coronary Artery Risk Development in Young Adults) study, a multi-center, community-based, longitudinal cohort study of CVD risk, the CAC and AAC scores were assessed in 3011 participants in 2010-2011 with follow-up until 2019 for incident CVD and CHD events. Distributions and predictions, overall and by race, were computed. During the 8-year follow-up, 106 incident CVD events (55 were CHD) occurred. AAC scores tended to be much higher than CAC scores. AAC scores were higher in Black women than in White women. CAC predicted CVD with HR 1.77 (1.52-2.06) and similarly for AAC, while only CAC predicted CHD. After adjustment for risk factors and calcium in the other arterial bed, the association of CAC with CVD was independent of risk factors and AAC, while the association of AAC with CVD was greatly attenuated. However, AAC predicted incident CVD when CAC was 0. Prediction did not vary by race. Conclusions AAC predicted CVD nearly as strongly as CAC and could be especially useful as a diagnostic tool when it is an incidental finding or when no CAC is found.

Elevated Aortic Pulse Wave Velocity Relates to Longitudinal Gray and White Matter Changes

OBJECTIVE

To determine whether baseline aortic stiffness, measured by aortic pulse wave velocity (PWV), relates to longitudinal cerebral gray or white matter changes among older adults. Baseline cardiac magnetic resonance imaging will be used to assess aortic PWV while brain magnetic resonance imaging will be used to assess gray matter and white matter hyperintensity (WMH) volumes at baseline, 18 months, 3 years, 5 years, and 7 years. Approach and Results: Aortic PWV (m/s) was quantified from cardiac magnetic resonance. Multimodal 3T brain magnetic resonance imaging included T₁-weighted imaging for quantifying gray matter volumes and T₂-weighted fluid-attenuated inversion recovery imaging for quantifying WMHs. Mixed-effects regression models related baseline aortic PWV to longitudinal gray matter volumes (total, frontal, parietal, temporal, occipital, hippocampal, and inferior lateral ventricle) and WMH volumes (total, frontal, parietal, temporal, and occipital) adjusting for age, sex, race/ethnicity, education, cognitive diagnosis, Framingham stroke risk profile, APOE (apolipoprotein E)-ε4 carrier status, and intracranial volume. Two hundred seventy-eight participants (73±7 years, 58% male, 87% self-identified as non-Hispanic White, 159 with normal cognition, and 119 with mild cognitive impairment) from the Vanderbilt Memory & Aging Project (n=335) were followed on average for 4.9±1.6 years with PWV measurements occurring from September 2012 to November 2014 and longitudinal brain magnetic resonance imaging measurements occurring from September 2012 to June 2021. Higher baseline aortic PWV was related to greater decrease in hippocampal (β=-3.6 [mm³/y]/[m/s]; [95% CI, -7.2 to -0.02] P=0.049) and occipital lobe (β=-34.2 [mm³/y]/[m/s]; [95% CI, -67.8 to -0.55] P=0.046) gray matter volume over time. Higher baseline aortic PWV was related to greater increase in WMH volume over time in the temporal lobe (β=17.0 [mm³/y]/[m/s]; [95% CI, 7.2-26.9] P<0.001). All associations may be driven by outliers.

CONCLUSIONS

In older adults, higher baseline aortic PWV related to greater decrease in gray matter volume and greater increase in WMHs over time. Because of unmet cerebral metabolic demands and microvascular remodeling, arterial stiffening may preferentially affect certain highly active brain regions like the temporal lobes. These same regions are affected early in the course of Alzheimer disease.

Relative associations of abdominal and thigh compositions with cardiometabolic diseases in African Caribbean men

BACKGROUND

Regional body compositions are differentially associated with cardiometabolic risk factors. Simultaneous inclusion of both upper and lower body composition predictors in models is not often done, and studies which do include both measures (1) tend to exclude some tissue(s) of potential metabolic relevance, and (2) have used study populations with underrepresentation of individuals with African ancestries. Further, most body composition analyses do not employ compositional data analytic approaches, which may result in spurious associations.

OBJECTIVE

The objective of this analysis was to assess associations of abdominal and thigh adipose (AT) and muscle tissues with hypertension and type 2 diabetes using compositional data analytic methods.

RESEARCH DESIGN AND METHODS

This cross-sectional analysis included 610 African Caribbean men (median age: 62 years; mean BMI: 27.8 kg/m2). Abdominal (three components: subcutaneous [ASAT] and visceral [VAT] AT, 'other' abdominal tissue) and mid-thigh (four components: subcutaneous and intermuscular AT, muscle, bone) compositions were measured by computed tomography; additive log ratio transformations were applied to each composition. Regression models were used to simultaneously assess associations of abdominal and thigh component ratios with continuous risk factors (blood pressures, fasting glucose and insulin, HOMA-IR) and disease categories.

RESULTS

A two-fold increase in ASAT:'Other' ratio was associated with higher continuous risk factors and with odds of being in a higher hypertension (OR: 1.77, 95%CI: 1.10-2.84) or diabetes (OR: 1.81, 95%CI: 1.06-3.10) category. A two-fold increased VAT ratio was only associated with higher log-insulin and log-HOMA-IR (β = 0.10, p < 0.05 for both), while a two-fold increased thigh muscle:bone ratio was associated with a lower diabetes category (OR: 0.37, 95%CI: 0.14-1.01).

CONCLUSIONS

These findings support ASAT as a significant driver of cardiometabolic disease in African Ancestry populations, independent of other abdominal and thigh tissues.

Association of Aortic Stiffness With Biomarkers of Neuroinflammation, Synaptic Dysfunction, and Neurodegeneration

OBJECTIVES

To test the hypothesis that increased aortic stiffening is associated with greater CSF evidence of core Alzheimer disease pathology (β-amyloid [Aβ], phosphorylated tau [p-tau]), neurodegeneration (total tau [t-tau]), synaptic dysfunction (neurogranin), neuroaxonal injury (neurofilament light [NFL]), and neuroinflammation (YKL-40, soluble triggering receptor expressed on myeloid cells 2 [sTREM2]), we analyzed pulse wave velocity (PWV) data and CSF data among older adults.

METHODS

Participants free of stroke and dementia from the Vanderbilt Memory and Aging Project, an observational community-based study, underwent cardiac magnetic resonance to assess aortic PWV (meters per second) and lumbar puncture to obtain CSF. Linear regressions related aortic PWV to CSF Aβ, p-tau, t-tau, neurogranin, NFL, YKL-40, and sTREM2 concentrations after adjustment for age, race/ethnicity, education, apolipoprotein (APOE) ε4 status, Framingham Stroke Risk Profile, and cognitive diagnosis. Models were repeated testing PWV interactions with age, diagnosis, APOE ε4, and hypertension on each biomarker.

RESULTS

One hundred forty-six participants were examined (age 72 ± 6 years). Aortic PWV interacted with age on p-tau (β = 0.31, p = 0.04), t-tau, (β = 2.67, p = 0.05), neurogranin (β = 0.94, p = 0.04), and sTREM2 (β = 20.4, p = 0.05). Among participants >73 years of age, higher aortic PWV related to higher p-tau (β = 2.4, p = 0.03), t-tau (β = 19.3, p = 0.05), neurogranin (β = 8.4, p = 0.01), and YKL-40 concentrations (β = 7,880, p = 0.005). Aortic PWV had modest interactions with diagnosis on neurogranin (β = -10.76, p = 0.03) and hypertension status on YKL-40 (β = 18,020, p < 0.001).

CONCLUSIONS

Among our oldest participants, ≥74 years of age, greater aortic stiffening is associated with in vivo biomarker evidence of neuroinflammation, tau phosphorylation, synaptic dysfunction, and neurodegeneration, but not amyloidosis. Central arterial stiffening may lead to cumulative cerebral microcirculatory damage and reduced blood flow delivery to tissue, resulting in neuroinflammation and neurodegeneration in more advanced age.

Allele-specific variation at APOE increases nonalcoholic fatty liver disease and obesity but decreases risk of Alzheimer's disease and myocardial infarction

Nonalcoholic fatty liver disease (NAFLD) is a leading cause of chronic liver disease and is highly correlated with metabolic disease. NAFLD results from environmental exposures acting on a susceptible polygenic background. This study performed the largest multiethnic investigation of exonic variation associated with NAFLD and correlated metabolic traits and diseases. An exome array meta-analysis was carried out among eight multiethnic population-based cohorts (n = 16 492) with computed tomography (CT) measured hepatic steatosis. A fixed effects meta-analysis identified five exome-wide significant loci (P < 5.30 × 10-7); including a novel signal near TOMM40/APOE. Joint analysis of TOMM40/APOE variants revealed the TOMM40 signal was attributed to APOE rs429358-T; APOE rs7412 was not associated with liver attenuation. Moreover, rs429358-T was associated with higher serum alanine aminotransferase, liver steatosis, cirrhosis, triglycerides and obesity; as well as, lower cholesterol and decreased risk of myocardial infarction and Alzheimer's disease (AD) in phenome-wide association analyses in the Michigan Genomics Initiative, United Kingdom Biobank and/or public datasets. These results implicate APOE in imaging-based identification of NAFLD. This association may or may not translate to nonalcoholic steatohepatitis; however, these results indicate a significant association with advanced liver disease and hepatic cirrhosis. These findings highlight allelic heterogeneity at the APOE locus and demonstrate an inverse link between NAFLD and AD at the exome level in the largest analysis to date.

Hepatic Steatosis and Ectopic Fat Are Associated With Differences in Subcutaneous Adipose Tissue Gene Expression in People With HIV

Persons with human immunodeficiency virus (PWH) have subcutaneous adipose tissue (SAT) dysfunction related to antiretroviral therapy and direct viral effects, which may contribute to a higher risk of nonalcoholic fatty liver disease compared with human immunodeficiency virus-negative individuals. We assessed relationships between SAT expression of major adipocyte regulatory and lipid storage genes with hepatic and other ectopic lipid deposits in PWH. We enrolled 97 PWH on long-term antiretroviral therapy with suppressed plasma viremia and performed computed tomography measurements of liver attenuation, a measure of hepatic steatosis, skeletal muscle (SM) attenuation, and the volume of abdominal subcutaneous, visceral, and pericardial adipose tissue. Whole SAT gene expression was measured using the Nanostring platform, and relationships with computed tomography imaging and fasting lipids were assessed using multivariable linear regression and network mapping. The cohort had a mean age of 47 years, body mass index of 33.4 kg/m2, and CD4 count of 492 cells/mm3. Lower liver attenuation, a marker of greater steatosis, was associated with differences in SAT gene expression, including lower lipoprotein lipase and acyl-CoA dehydrogenase, and higher phospholipid transfer protein. Lower liver attenuation clustered with lower visceral adipose tissue (VAT) attenuation and greater VAT volume, pericardial fat volume and triglycerides, but no relationship was observed between liver attenuation and SAT volume, SM attenuation, or low-density lipoprotein. Conclusion: Liver attenuation was associated with altered SAT expression of genes regulating lipid metabolism and storage, suggesting that SAT dysfunction may contribute to nonalcoholic fatty liver disease in PWH. SAT gene-expression relationships were similar for VAT volume and attenuation, but not SM, indicating that ectopic lipid deposition may involve multiple pathways.

Abstract 071: Ten-year Change In Tv Viewing Is Associated With Concurrent Change In Pericardial Adipose Tissue In Middle-aged Adults: The Coronary Artery Risk Development In Young Adults (CARDIA) Study

Introduction: Pericardial adipose tissue (PAT), an ectopic adipose depot surrounding the coronary arteries, is a pathogenic risk factor for cardiometabolic disease; however, the association of sedentary behavior with PAT is poorly understood. We examined the longitudinal association of 10-year change in TV viewing with concurrent change in PAT.

Hypothesis: Increased h/day of TV viewing over 10 years are associated with larger mean increases in PAT during the same 10-year period.

Methods: Middle-aged adults (N=1659, mean age=40.4, 912 females, 733 blacks) from the Coronary Artery Risk Development in Young Adults (CARDIA) Study at the exam years 15 (2000-2001) and 25 (2010-2011) were included. Both TV viewing (h/day) and the volume of PAT (mL) were measured at Years 15 and 25 using the CARDIA physical activity questionnaire and computed tomography, respectively. Covariates measured at year 15 included PAT, sociodemographic factors, cardiovascular disease risk factors, diet quality, TV viewing, moderate-to-vigorous intensity physical activity (MVPA), inflammatory cytokines, and waist circumference. Multivariable linear regression was used to estimate 10-year change in PAT across increasing tertiles (≤ -1, > -1 to < 1, ≥ 1 h/day) of 10-year changes in TV viewing.

Results: On average, TV viewing and PAT increased between the two exam years by 0.2 h/day (8.7% increase, mean: 2.3 → 2.5 h/day) and 11.8 mL (25.9% increase, mean: 45.6 → 57.4 mL), respectively (all p < 0.01). In the fully adjusted model including MVPA and other major confounders, the highest tertile of 10-year change in TV viewing was associated with greater change in PAT (β = 2.97 mL, p < 0.01) when compared with the lowest tertile (see Figure 1 ), while mean PAT change was intermediate in the middle tertile.

Conclusions: A greater 10-year increase in TV viewing is associated with a greater concurrent increase in PAT, independent of MVPA and other important confounders. Reducing TV viewing time may be associated with less PAT accumulation with age.

Association Between Ambulatory Blood Pressure and Coronary Artery Calcification: The JHS

[Figure: see text].