Ramin Farzaneh-Far

Association of marine omega-3 fatty acid levels with telomeric aging in patients with coronary heart disease

CONTEXT Increased dietary intake of marine omega-3 fatty acids is associated with prolonged survival in patients with coronary heart disease. However, the mechanisms underlying this protective effect are poorly understood. OBJECTIVE To investigate the association of omega-3 fatty acid blood levels with temporal changes in telomere length, an emerging marker of biological age. DESIGN, SETTING, AND PARTICIPANTS Prospective cohort study of 608 ambulatory outpatients in California with stable coronary artery disease recruited from the Heart and Soul Study between September 2000 and December 2002 and followed up to January 2009 (median, 6.0 years; range, 5.0-8.1 years). MAIN OUTCOME MEASURES We measured leukocyte telomere length at baseline and again after 5 years of follow-up. Multivariable linear and logistic regression models were used to investigate the association of baseline levels of omega-3 fatty acids (docosahexaenoic acid [DHA] and eicosapentaenoic acid [EPA]) with subsequent change in telomere length. RESULTS Individuals in the lowest quartile of DHA+EPA experienced the fastest rate of telomere shortening (0.13 telomere-to-single-copy gene ratio [T/S] units over 5 years; 95% confidence interval [CI], 0.09-0.17), whereas those in the highest quartile experienced the slowest rate of telomere shortening (0.05 T/S units over 5 years; 95% CI, 0.02-0.08; P < .001 for linear trend across quartiles). Levels of DHA+EPA were associated with less telomere shortening before (unadjusted beta coefficient x 10(-3) = 0.06; 95% CI, 0.02-0.10) and after (adjusted beta coefficient x 10(-3) = 0.05; 95% CI, 0.01-0.08) sequential adjustment for established risk factors and potential confounders. Each 1-SD increase in DHA+EPA levels was associated with a 32% reduction in the odds of telomere shortening (adjusted odds ratio, 0.68; 95% CI, 0.47-0.98). CONCLUSION Among this cohort of patients with coronary artery disease, there was an inverse relationship between baseline blood levels of marine omega-3 fatty acids and the rate of telomere shortening over 5 years.

Prognostic Value of Leukocyte Telomere Length in Patients With Stable Coronary Artery Disease. Data From the Heart and Soul Study

Background—Telomere shortening has been proposed as a marker of biological aging. Whether leukocyte telomere length is associated with mortality among patients with stable coronary artery disease (CAD) is unknown. Methods and Results—We measured leukocyte telomere length in 780 patients with stable CAD in a prospective cohort study. Participants were categorized by quartiles of telomere length. Hazard Ratios (HRs) and 95% confidence intervals were calculated for all-cause mortality, heart failure (HF) hospitalization, and cardiovascular (CV) events. After 4.4 years of follow-up there were 166 deaths. Compared with participants in the highest telomere length quartile, those in the lowest quartile were at increased risk of death (age-adjusted HR 1.8; 95% CI 1.2 to 2.9). After multivariate adjustment for clinical (HR 2.1; CI 1.3 to 3.3), inflammatory (HR 2.0; CI 1.2 to 3.2), and echocardiographic (HR 1.9; CI 1.0 to 3.5) risk factors, patients in the lowest quartile of telomere length remained at significantly increased risk of death compared to those in the highest quartile. Patients in the lowest quartile of telomere length were also at significantly increased risk of HF hospitalization (HR 2.6; CI 1.1 to 6.0) but not CV events (HR 1.7; CI 0.9 to 3.5). Conclusions—Reduced leukocyte telomere length is associated with all-cause mortality in patients with stable CAD. The prognostic value of short telomeres in predicting death is not completely captured by existing clinical, inflammatory, and echocardiographic markers of risk.

Telomere Length Trajectory and Its Determinants in Persons with Coronary Artery Disease: Longitudinal Findings from the Heart and Soul Study

Background Leukocyte telomere length, an emerging marker of biological age, has been shown to predict cardiovascular morbidity and mortality. However, the natural history of telomere length in patients with coronary artery disease has not been studied. We sought to investigate the longitudinal trajectory of telomere length, and to identify the independent predictors of telomere shortening, in persons with coronary artery disease. Methodology/Principal Findings In a prospective cohort study of 608 individuals with stable coronary artery disease, we measured leukocyte telomere length at baseline, and again after five years of follow-up. We used multivariable linear and logistic regression models to identify the independent predictors of leukocyte telomere trajectory. Baseline and follow-up telomere lengths were normally distributed. Mean telomere length decreased by 42 base pairs per year (p<0.001). Three distinct telomere trajectories were observed: shortening in 45%, maintenance in 32%, and lengthening in 23% of participants. The most powerful predictor of telomere shortening was baseline telomere length (OR per SD increase = 7.6; 95% CI 5.5, 10.6). Other independent predictors of telomere shortening were age (OR per 10 years = 1.6; 95% CI 1.3, 2.1), male sex (OR = 2.4; 95% CI 1.3, 4.7), and waist-to-hip ratio (OR per 0.1 increase = 1.4; 95% CI 1.0, 2.0). Conclusions/Significance Leukocyte telomere length may increase as well as decrease in persons with coronary artery disease. Telomere length trajectory is powerfully influenced by baseline telomere length, possibly suggesting negative feedback regulation. Age, male sex, and abdominal obesity independently predict telomere shortening. The mechanisms and reversibility of telomeric aging in cardiovascular disease deserve further study.

Inverse association of erythrocyte n-3 fatty acid levels with inflammatory biomarkers in patients with stable coronary artery disease: The Heart and Soul Study

OBJECTIVE Dietary intake of polyunsaturated n-3 fatty acids has been associated with a reduced incidence of adverse cardiovascular events. The protective mechanisms involved are not fully understood, but may include anti-inflammatory factors. We sought to investigate the relationship between n-3 fatty acid levels in erythrocyte membranes and markers of systemic inflammation in 992 individuals with stable coronary artery disease. METHODS Cross-sectional associations of C-reactive protein (CRP) and Interleukin-6 (Il-6) with docosahexaenoic acid (DHA) and eicosapentaenoic acid (EHA) were evaluated in multivariable linear regression models adjusted for demographics, cardiovascular risk factors, medication use, exercise capacity, body-mass index, and waist-to-hip ratio. RESULTS After multivariable adjustment, n-3 fatty acid levels (DHA+EPA) were inversely associated with CRP and IL-6. The inverse association of n-3 fatty acids with CRP and IL-6 was not modified by demographics, body-mass index, smoking, LDL-cholesterol, or statin use (p values for interaction>0.1). CONCLUSIONS In patients with stable coronary artery disease, an independent and inverse association exists between n-3 fatty acid levels and inflammatory biomarkers. These findings suggest that inhibition of systemic inflammation may be a mechanism by which n-3 fatty acids prevent recurrent cardiovascular events.

Depression and Leukocyte Telomere Length in Patients With Coronary Heart Disease : Data From The Heart and Soul Study

Objective: Shortened telomere length has been associated with mortality in patients with coronary heart disease (CHD) and is considered as an emerging marker of biologic age. Whether depression is associated with telomere length or trajectory has not been evaluated in patients with CHD. Methods: In a prospective cohort study, we measured leukocyte telomere length in 952 participants with stable CHD at baseline and in 608 of these participants after 5 years of follow-up. The presence of major depressive disorder in the past month was assessed using the computerized diagnostic interview schedule at baseline. We used linear and logistic regression models to evaluate the association of depression with baseline and 5-year change in leukocyte telomere length. Results: Of the 952 participants, 206 (22%) had major depression at baseline. After the adjustment for age and sex, the patients with current major depressive disorder had shorter baseline telomere length than those without depression (mean [standard error] = 0.86 [0.02] versus 0.90 [0.01]; p =.02). This association was similar (but no longer statistically significant) after adjustment for body mass index, smoking, diabetes, left ventricular ejection fraction, statin use, antidepressant use, physical inactivity, and anxiety (0.85 [0.02] versus 0.89 [0.01], p =.06). Depression was not predictive of 5-year change in telomere length after adjustment for the mentioned covariates and baseline telomere length. Conclusions: Depression is associated with reduced leukocyte telomere length in patients with CHD but does not predict 5-year change in telomere length. Future research is necessary to elucidate the potential mechanisms underlying the association between depression and telomere length.CHD = coronary heart disease; MDD = major depressive disorder; CDIS-IV = computerized diagnostic interview schedule; MI = myocardial infarction; PHQ = Patient Health Questionnaire; BMI = body mass index; LVEF = left ventricular ejection fraction

Physical Fitness and Risk for Heart Failure and Coronary Artery Disease

Background—Multiple studies have demonstrated strong associations between cardiorespiratory fitness and lower cardiovascular disease mortality. In contrast, little is known about associations of fitness with nonfatal cardiovascular events. Methods and Results—Linking individual participant data from the Cooper Center Longitudinal Study with Medicare claims files, we studied 20 642 participants (21% women) with fitness measured at the mean age of 49 years and who survived to receive Medicare coverage from 1999 to 2009. Fitness was categorized into age- and sex-specific quintiles (Q) according to Balke protocol treadmill time with Q1 as low fitness. Fitness was also estimated in metabolic equivalents according to treadmill time. Associations between midlife fitness and hospitalizations for heart failure and acute myocardial infarction after the age of 65 years were assessed by applying a proportional hazards model to the multivariate failure time data. After 133 514 person-years of Medicare follow-up, we observed 1051 hospitalizations for heart failure and 832 hospitalizations for acute myocardial infarction. Compared with high fitness (Q4–5), low fitness (Q1) was associated with a higher rate of heart failure hospitalization (14.3% versus 4.2%) and hospitalization for myocardial infarction (9.7% versus 4.5%). After multivariable adjustment for baseline age, blood pressure, diabetes mellitus, body mass index, smoking status, and total cholesterol, a 1 unit greater fitness level in metabolic equivalents achieved in midlife was associated with ≈20% lower risk for heart failure hospitalization after the age of 65 years (men: hazard ratio [95% confidence intervals], 0.79 [0.75–0.83]; P<0.001 and women: 0.81 [0.68–0.96]; P=0.01) but just a 10% lower risk for acute myocardial infarction in men (0.91 [0.87–0.95]; P<0.001) and no association in women (0.97 [0.83–1.13]; P=0.68). Conclusions—Fitness in healthy, middle-aged adults is more strongly associated with heart failure hospitalization than acute myocardial infarction outcomes decades later in older age.

A Functional Polymorphism in Renalase (Glu37Asp) Is Associated with Cardiac Hypertrophy, Dysfunction, and Ischemia: Data from the Heart and Soul Study

Background Renalase is a soluble enzyme that metabolizes circulating catecholamines. A common missense polymorphism in the flavin-adenine dinucleotide-binding domain of human renalase (Glu37Asp) has recently been described. The association of this polymorphism with cardiac structure, function, and ischemia has not previously been reported. Methods We genotyped the rs2296545 single-nucleotide polymorphism (Glu37Asp) in 590 Caucasian individuals and performed resting and stress echocardiography. Logistic regression was used to examine the associations of the Glu37Asp polymorphism (C allele) with cardiac hypertrophy (LV mass>100 g/m2), systolic dysfunction (LVEF<50%), diastolic dysfunction, poor treadmill exercise capacity (METS<5) and inducible ischemia. Results Compared with the 406 participants who had GG or CG genotypes, the 184 participants with the CC genotype had increased odds of left ventricular hypertrophy (OR = 1.43; 95% CI 0.99–2.06), systolic dysfunction (OR = 1.72; 95% CI 1.01–2.94), diastolic dysfunction (OR = 1.75; 95% CI 1.05–2.93), poor exercise capacity (OR = 1.61; 95% CI 1.05–2.47), and inducible ischemia (OR = 1.49, 95% CI 0.99–2.24). The Glu37Asp (CC genotype) caused a 24-fold decrease in affinity for NADH and a 2.3-fold reduction in maximal renalase enzymatic activity. Conclusions A functional missense polymorphism in renalase (Glu37Asp) is associated with cardiac hypertrophy, ventricular dysfunction, poor exercise capacity, and inducible ischemia in persons with stable coronary artery disease. Further studies investigating the therapeutic implications of this polymorphism should be considered.

First-degree atrioventricular block is associated with heart failure and death in persons with stable coronary artery disease: data from the Heart and Soul Study

AIMS First-degree atrioventricular block (AVB) has traditionally been considered a benign electrocardiographic finding in healthy individuals. However, the clinical significance of first-degree AVB has not been evaluated in patients with stable coronary heart disease. We investigated whether first-degree AVB is associated with heart failure (HF) and mortality in a prospective cohort study of outpatients with stable coronary artery disease (CAD). METHODS AND RESULTS We measured the P-R interval in 938 patients with stable CAD and classified them into those with (P-R interval ≥ 220 ms) and without (P-R interval <220 ms) first-degree AVB. Hazard ratios (HRs) and 95% confidence intervals were calculated for HF hospitalization and all-cause mortality. During 5 years of follow-up, there were 123 hospitalizations for HF and 285 deaths. Compared with patients who had normal atrioventricular conduction, those with first-degree AVB were at increased risk for HF hospitalization (age-adjusted HR 2.33: 95% CI 1.49-3.65; P= 0.0002), mortality [age-adjusted HR 1.58; 95% CI (1.13-2.20); P = 0.008], cardiovascular (CV) mortality [age-adjusted HR 2.33; 95% CI (1.28-4.22); P= 0.005], and the combined endpoint of HF hospitalization or CV mortality (age-adjusted HR 2.43: 95% CI 1.64-3.61; P ≤ 0.0001). These associations persisted after multivariable adjustment for heart rate, medication use, ischaemic burden, and QRS duration. Adjustment for left ventricular systolic and diastolic function partially attenuated the effect, but first-degree AVB remained associated with the combined endpoint of HF or CV death (HR 1.61, CI 1.02-2.54; P= 0.04). CONCLUSION In a large cohort of patients with stable coronary artery disease, first-degree AVB is associated with HF and death.

Development of an Echocardiographic Risk-Stratification Index to Predict Heart Failure in Patients With Stable Coronary Artery Disease: The Heart and Soul Study

OBJECTIVES We sought to determine which transthoracic echocardiographic (TTE) measurements most strongly predict heart failure (HF) and to develop an index for risk stratification in outpatients with coronary artery disease (CAD). BACKGROUND Many TTE measurements have been shown to be predictive of HF, and they might be useful if aggregated into a risk-prediction index. METHODS We performed TTE in 1,024 outpatients with stable CAD enrolled in the Heart and Soul study and followed them for 4.4 years. With Cox proportional hazard models, we evaluated the association of 15 TTE measurements with subsequent HF hospital stay. Those measurements that independently predicted HF were combined into an index. Variables were defined as normal or abnormal on the basis of dichotomous cutoffs determined from the American Society of Echocardiography. Abnormal variables in each measurement were assigned points on the basis of strength of association with HF. RESULTS Of the 15 variables, 5 measurements were independent predictors of HF: left ventricular mass index (LVMI), left atrial volume index (LAVI), mitral regurgitation (MR), left ventricular outflow tract velocity-time integral (VTI(LVOT)), and diastolic dysfunction (DD). In multivariate analysis, each of the 5 measurements independently predicted HF: LVMI >90 g/m(2) (hazard ratio [HR]: 4.1; 95% confidence interval [CI]: 2.3 to 7.2, p < 0.0001); pseudo-normal or restrictive DD (HR: 2.9; 95% CI: 1.8 to 4.5, p < 0.0001); VTI(LVOT) <22 mm (HR: 2.2; 95% CI: 1.4 to 3.5, p = 0.0004); mild, moderate, or severe MR (HR: 1.8; 95% CI: 1.2 to 2.8, p = 0.009); and LAVI >29 ml/m(2) (HR: 1.6; 95% CI: 1.0 to 2.5, p < 0.06). Combining these measurements, the Heart Failure Index ranged from 0 to 8, representing risk as follows: 3 points for LVMI, 2 points for DD, and 1 point for VTI(LVOT), MR, and LAVI. Among participants with 0 to 2 points: 4% had HF hospital stays (reference); 3 to 4 points: 10% (HR: 2.4; 95% CI: 1.3 to 4.4, p = 0.003); 5 to 6 points: 24% (HR: 6.2; 95% CI: 3.6 to 10.6, p < 0.0001); 7 to 8 points: 48% (HR: 13.7; 95% CI: 7.2 to 25.9, p < 0.0001). CONCLUSIONS We identified 5 TTE measurements that independently predict HF in patients with stable CAD and combined them as an index that might be useful for risk stratification and serial observations.

Association of low leptin with cardiovascular events and mortality in patients with stable coronary artery disease: The Heart and Soul Study

OBJECTIVE Leptin is an adipokine with both protective and harmful effects on the cardiovascular (CV) system. Prior studies evaluating the association between leptin and CV outcomes have yielded conflicting results. Thus, we sought to investigate the relationship between leptin and CV events and mortality in patients with chronic stable coronary artery disease (CAD). METHODS We performed a prospective cohort study of 981 outpatients with stable CAD. Leptin levels were measured in fasting venous samples at baseline. We used proportional hazards models to evaluate the association of baseline leptin with subsequent CV events (myocardial infarction, stroke, transient ischemic attack) and death. RESULTS During a mean follow-up of 6.2±2.1 years, there were 304 deaths, 112 myocardial infarctions, and 52 strokes/TIAs. In models adjusted for age, sex, and race, low leptin was associated with a 30% increased risk of the combined outcome (HR 1.30, CI 1.05-1.59, p=0.01). After further adjustment for obesity, traditional CV risk factors and biomarkers, low leptin remained associated with a 37% increased risk of events (HR 1.37, CI 1.06-1.76, p=0.02). CONCLUSIONS Low leptin is associated with increased CV events and mortality in patients with stable coronary artery disease. This association is independent of known factors affecting leptin levels, including gender and obesity.