Project description:BackgroundSerum N-terminal pro-B-type natriuretic peptide (NT-proBNP) is considered a marker that is expressed in response to myocardial strain and possibly fibrosis. However, the relationship to myocardial fibrosis in a community-based population is unknown.ObjectivesThe authors evaluated the relationship between cardiac magnetic resonance (CMR) measures of fibrosis and NT-proBNP levels in the MESA (Multi-Ethnic Study of Atherosclerosis) study.MethodsA total of 1,334 participants (52% white, 23% black, 11% Chinese, 14% Hispanic, and 52% men with a mean age of 67.6 years) at 6 sites had both serum NT-proBNP measurements and CMR with T1 mapping of indices of fibrosis at 1.5 T. Univariate and multivariable regression analyses adjusting for demographics, cardiovascular risk factors, and left ventricular (LV) mass were performed to examine the association of log NT-proBNP with CMR T1 mapping indices.ResultsIn the fully adjusted model, each 1-SD increment (0.44 pg/ml) of log NT-proBNP was associated with a 0.62% increment in extracellular volume fraction (p < 0.001), 0.011 increment in partition coefficient (p < 0.001), and 4.7-ms increment in native T1 (p = 0.001). Results remained unchanged after excluding individuals with clinical cardiovascular disease or late gadolinium enhancement (n = 167), and after replacing LV mass by LV end-diastolic volume in the regression models.ConclusionsElevated NT-proBNP is related to subclinical fibrosis in a community-based setting. (Multi-Ethnic Study of Atherosclerosis [MESA]; NCT00005487).
Project description:BackgroundIncreasing evidence suggests that elevated plasma fibrinogen is associated with incident heart failure. However, the underlying pathophysiological mechanisms have not been well elucidated.MethodsWe examined the relationship between plasma fibrinogen level and peak systolic midwall circumferential strain (Ecc) at the base, mid cavity, and apex of the left ventricle measured by magnetic resonance imaging myocardial tagging in 1096 participants without clinical cardiovascular disease enrolled in the Multi-Ethnic Study of Atherosclerosis (MESA).ResultsAfter adjustment for demographics, established risk factors and body mass index, elevated fibrinogen was independently associated with reductions in absolute Ecc indicative of impaired systolic function in all regions (all P < or = .015). The relationships were consistently significant upon further adjustment for measures of atherosclerosis (all P < .024) and were modestly attenuated with regional heterogeneity after additional adjustment for other inflammatory biomarker and N-terminal pro-brain natriuretic peptide. In this fully-adjusted model, every 1-SD (74 mg/dL) increment in plasma fibrinogen was independently associated with a reduction in left ventricular absolute Ecc of 0.29% (95% CI 0.03%-0.59%, P = .048) at the base, 0.22% (95% CI 0.006%-0.43%, P = .044) at mid cavity, 0.20% (95% CI = -0.035% to 0.43%, P = .097) at the apex, and 0.24% (95% CI = 0.05%-0.43%, P = .015) overall.ConclusionsAmong asymptomatic individuals without clinical cardiovascular disease, elevated fibrinogen is independently associated with impaired myocardial systolic function. These findings support roles of inflammation, procoagulation, and hyperviscosity underlying hyperfibrinogenemia in the pathogenesis of incipient myocardial dysfunction.
Project description:ObjectivesExamine the associations of sleep measures with kidney function changes over time among individuals from a community-based study.MethodsThe sample includes 1657 participants (287 with chronic kidney disease [CKD]) in the Multi-Ethnic Study of Atherosclerosis Sleep Cohort (mean age: 57.7 years, male: 46.0%). We examined associations between a large set of sleep variables (polysomnography, actigraphy, and questionnaires) and cardiovascular disease risk factors and changes in estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatinine ratio over approximately 5 years using high-dimensional regression. We investigated the modifying effect of sleep on the associations between cardiovascular disease risk factors and kidney function.ResultsSleep metrics predicted kidney function decline only among individuals with baseline CKD. Among this group, eGFR decline was associated with decreased stage N3 sleep (0.32 mL/min/1.73 m2/y per 10% decrease in N3, p < .001); increased actigraphy napping frequency (beta: -0.20 [-0.30, -0.07]); and actigraphy sleep midpoint trajectory in early morning (ref: midnight, beta: -0.84 [-1.19, -0.50]). Urinary albumin-to-creatinine ratio increase was associated with high wake bouts trajectory (ref: low, beta: 0.97 [0.28, 1.67]) and increased sleep-related hypoxemia (oxygen saturation %time<90 [≥5%], beta: 2.17 [1.26, 3.08]). Sleep metrics--N3 sleep, naps, and midpoint trajectory--significantly modified associations between hemoglobin A1C and eGFR decline.ConclusionsReduced deep sleep, daytime napping, increased wake bouts, delayed sleep rhythms, and overnight hypoxemia are associated with longitudinal kidney function decline, with effects most apparent in individuals with CKD. Deep sleep, napping, and sleep timing modified the association between hemoglobin A1C and kidney function.
Project description:BackgroundTagged cardiac magnetic resonance provides detailed information on regional myocardial function and mechanical behavior. T1 mapping by cardiac magnetic resonance allows noninvasive quantification of myocardial extracellular expansion (ECE), which has been related to interstitial fibrosis in previous clinical and subclinical studies. We assessed sex-associated differences in the relation of ECE to left ventricular (LV) remodeling and myocardial systolic and diastolic deformation in a large community-based multiethnic population.Methods and resultsMidventricular midwall peak circumferential shortening and early diastolic strain rate and LV torsion and torsional recoil rate were determined using cardiac magnetic resonance tagging. Midventricular short-axis T1 maps were acquired in the same examination pre- and postcontrast injection using Modified Look-Locker Inversion-Recovery sequence. Multivariable linear regression (estimated regression coefficient, B) was used to adjust for risk factors and subclinical disease measures. Of 1230 participants, 114 had a visible myocardial scar by late gadolinium enhancement. Participants without a visible myocardial scar (n=1116) had no history of previous clinical events. In the latter group, multivariable linear regression demonstrated that lower postcontrast T1 times, reflecting greater ECE, were associated with lower circumferential shortening (B=-0.1; P=0.0001), lower LV end-diastolic volume index (B=0.6; P=0.0001), and lower LV end-diastolic mass index (B=0.4; P=0.0001). In addition, lower postcontrast T1 times were associated with lower early diastolic strain rate (B=0.01; P=0.03) in women only and lower LV torsion (B=0.005; P=0.03) and lower LV ejection fraction (B=0.2, P=0.01) in men only.ConclusionsGreater ECE is associated with reduced LV end-diastolic volume index and LV end-diastolic mass index in a large multiethnic population without history of previous cardiovascular events. In addition, greater ECE is associated with reduced circumferential shortening, lower early diastolic strain rate, and a preserved ejection fraction in women, whereas in men, greater ECE is associated with greater LV dysfunction manifested as reduced circumferential shortening, reduced LV torsion, and reduced ejection fraction.
Project description:BackgroundRare pathogenic variants in cardiomyopathy (CM) genes can predispose to cardiac remodeling or fibrosis. We studied the carrier status for such variants in adults without clinical cardiovascular disease (CVD) in whom cardiac MRI (CMR)-derived measures of myocardial fibrosis were obtained in the Multi-Ethnic Study of Atherosclerosis (MESA).ObjectivesTo identify CM-associated pathogenic variants and assess their relative prevalence in participants with extensive myocardial fibrosis by CMR.MethodsMESA whole-genome sequencing data was evaluated to capture variants in CM-associated genes (n = 82). Coding variants with a frequency of <0.1% in gnomAD and 1,000 Genomes Project databases and damaging/deleterious effects based on in-silico scoring tools were assessed by ClinVar database and ACMG curation guidelines for evidence of pathogenicity. Cases were participants with high myocardial fibrosis defined as highest quartile of extracellular volume (ECV) or native T1 time in T1-mapping CMR and controls were the remainder of participants.ResultsA total of 1,135 MESA participants had available genetic data and phenotypic measures and were free of clinical CVD at the time of CMR. We identified 6,349 rare variants in CM-associated genes in the overall MESA population, of which six pathogenic/likely pathogenic (P/LP) variants were present in the phenotyped subpopulation. The genes harboring P/LP variants in the case group were MYH7, CRYAB, and SCN5A. The prevalence of P/LP rare variants in cases was higher than controls (5 in 420 [1.1%] vs. 1 in 715 [0.1%], p = 0.03). We identified two MYBPC3 Variants of Unknown Significance (VUS)s with borderline pathogenicity in the case group. The left ventricle (LV) volume, mass, ejection fraction (EF), and longitudinal and circumferential strain in participants with the variants were not different compared to the overall cohort.ConclusionsWe observed a higher prevalence of rare potentially pathogenic CM associated genetic variants in participants with significant myocardial fibrosis quantified in CMR as compared to controls without significant fibrosis. No cardiac structural or functional differences were found between participants with or without P/LP variants.
Project description:IntroductionThe contribution of occupational exposure to the risk of chronic obstructive pulmonary disease COPD in population-based studies is of interest. We compared the performance of self-reported exposure to a newly developed JEM in exposure-response evaluation.MethodsWe used cross-sectional data from Multi-Ethnic Study of Atherosclerosis (MESA), a population-based sample of 45-84 year olds free of clinical cardiovascular disease at baseline. MESA ascertained the most recent job and employment, and the MESA Lung Study measured spirometry, and occupational exposures for 3686 participants. Associations between health outcomes (spirometry defined airflow limitation and Medical Research Council-defined chronic bronchitis) and occupational exposure [self-reported occupational exposure to vapor-gas, dust, or fumes (VGDF), severity of exposure, and a job-exposure matrix (JEM)-derived score] were evaluated using logistic regression models adjusted for non-occupational risk factors.ResultsThe prevalence of airflow limitation was associated with self-reported exposure to vapor-gas (OR 2.6, 95%CI 1.1-2.3), severity of VGDF exposure (P-trend < 0.01), and JEM dust exposure (OR 2.4, 95%CI 1.1-5.0), and with organic dust exposure in females; these associations were generally of greater magnitude among never smokers. The prevalence of chronic bronchitis and wheeze was associated with exposure to VGDF. The association between airflow limitation and the combined effect of smoking and VGDF exposure showed an increasing trend. Self-reported vapor-gas, dust, fumes, years and severity of exposure were associated with increased prevalence of chronic bronchitis and wheeze (P < 0.001).ConclusionsAirflow limitation was associated with self-reported VGDF exposure, its severity, and JEM-ascertained dust exposure in smokers and never-smokers in this multiethnic study.
Project description:ObjectivesThere is limited research on racial/ethnic variation in sleep disturbances. This study aimed to quantify the distributions of objectively measured sleep disordered breathing (SDB), short sleep duration, poor sleep quality, and self-reported sleep disturbances (e.g., insomnia) across racial/ethnic groups.DesignCross-sectional study.SettingSix US communities.ParticipantsRacially/ethnically diverse men and women aged 54-93 y in the Multi-Ethnic Study of Atherosclerosis Sleep Cohort (n = 2,230).InterventionsN/A.Measurements and resultsInformation from polysomnography-measured SDB, actigraphy-measured sleep duration and quality, and self-reported daytime sleepiness were obtained between 2010 and 2013. Overall, 15.0% of individuals had severe SDB (apnea-hypopnea index [AHI] ≥ 30); 30.9% short sleep duration (< 6 h); 6.5% poor sleep quality (sleep efficiency < 85%); and 13.9% had daytime sleepiness. Compared with Whites, Blacks had higher odds of sleep apnea syndrome (AHI ≥ 5 plus sleepiness) (sex-, age-, and study site-adjusted odds ratio [OR] = 1.78, 95% confidence interval [CI]: 1.20, 2.63), short sleep (OR = 4.95, 95% CI: 3.56, 6.90), poor sleep quality (OR = 1.57, 95% CI: 1.00, 2.48), and daytime sleepiness (OR = 1.89, 95% CI: 1.38, 2.60). Hispanics and Chinese had higher odds of SDB and short sleep than Whites. Among non-obese individuals, Chinese had the highest odds of SDB compared to Whites. Only 7.4% to 16.2% of individuals with an AHI ≥ 15 reported a prior diagnosis of sleep apnea.ConclusionsSleep disturbances are prevalent among middle-aged and older adults, and vary by race/ethnicity, sex, and obesity status. The high prevalence of sleep disturbances and undiagnosed sleep apnea among racial/ethnic minorities may contribute to health disparities.
Project description:Background and aimsSubclinical atherosclerosis (sCVD), measured by coronary artery calcium (CAC) and carotid intima media thickness (CIMT) is associated with cardiovascular disease (CVD). Genome-Wide Association Studies (GWAS) of sCVD and CVD have focused primarily on Caucasian populations. We hypothesized that these associations may differ in populations from distinct genetic backgrounds.MethodsThe associations between sCVD and 66 single nucleotide polymorphisms (SNPs) from published GWAS of sCVD and CVD were tested in 8224 Multi-Ethnic Study of Atherosclerosis (MESA) and MESA Family participants [2329 Caucasians (EUA), 691 Chinese (CHN), 2482 African Americans (AFA), and 2012 Hispanic (HIS)] using an additive model adjusting for CVD risk factors, with SNP significance defined by a Bonferroni-corrected p < 7.6 × 10(-4) (0.05/66).ResultsIn EUA there were significant associations for CAC with SNPs in 9p21 (rs1333049, P = 2 × 10(-9); rs4977574, P = 4 × 10(-9)), COL4A1 (rs9515203, P = 9 × 10(-6)), and PHACTR1 (rs9349379, P = 4 × 10(-4)). In HIS, CAC was associated with SNPs in 9p21 (rs1333049, P = 8 × 10(-5); rs4977574, P = 5 × 10(-5)), APOA5 (rs964184, P = 2 × 10(-4)), and ADAMTS7 (rs7173743, P = 4 × 10(-4)). There were no associations between CAC and 9p21 SNPs for AFA and CHN. Fine mapping of the 9p21 region revealed SNPs with robust associations with CAC in EUA and HIS but no significant associations in AFA and CHN.ConclusionOur results suggest some shared genetic architecture for sCVD across ethnic groups, while also underscoring the possibility of novel variants and/or pathways in risk of CVD in ethnically diverse populations.