Circulating brain‐derived neurotrophic factor concentrations and the risk of cardiovascular disease in the community

BACKGROUND: Brain‐derived neurotrophic factor (BDNF) is a pleiotropic peptide involved in maintaining endothelial integrity. It is unknown if circulating BDNF levels are associated with risk of cardiovascular disease (CVD). METHODS AND RESULTS: We prospectively investigated the association of circulating BDNF levels with cardiovascular events and mortality in 3687 participants (mean age 65 years, 2068 women) from the Framingham Heart Study (FHS). Using a common nonsynonomous single nucleotide polymorphism (SNP) in the BDNF gene (rs6265), we then performed a Mendelian randomization experiment in the CARDIoGRAM (Coronary ARtery DIsease Genome‐Wide Replication And Meta‐Analysis) consortium (>22 000 coronary artery disease [CAD] cases, >60 000 controls) to investigate whether SNP rs6265 was associated with CAD in CARDIoGRAM and, if so, whether the effect estimate differed from that predicted based on FHS data. On follow‐up (median 8.9 years), 467 individuals (261 women) in FHS experienced a CVD event, and 835 (430 women) died. In multivariable‐adjusted Cox regression, serum BDNF was associated inversely with CVD risk (hazard ratio [HR] per 1‐SD increase 0.88, 95% CI 0.80 to 0.97, P=0.01) and with mortality (HR 0.87, 95% CI 0.80 to 0.93, P=0.0002). SNP rs6265 was associated with BDNF concentrations (0.772 ng/mL increase per minor allele copy) in FHS. In CARDIoGRAM, SNP rs6265 was associated with CAD (odds ratio 0.957, 95% CI 0.923 to 0.992), a magnitude consistent with the predicted effect (HR per minor allele copy 0.99, 95% CI 0.98 to 1.0; P=0.06 for difference between predicted and observed effect). CONCLUSION: Higher serum BDNF is associated with a decreased risk of CVD and mortality. Mendelian randomization suggests a causal protective role of BDNF in the pathogenesis of CVD

Secular trends in echocardiographic left ventricular mass in the community: the Framingham Heart Study

Objective: To investigate secular trends in echocardiographically determined left ventricular mass (LVM). Design, setting and participants: Longitudinal community-based cohort study in Framingham, Massachussetts. LVM was calculated from routine echocardiography in 4320 participants (52% women) of the Framingham offspring cohort at examination cycles 4 (1987–1991), 5 (1991–1995), 6 (1995–1998) and 8 (2005–2008), totalling 13 971 person-observations. Main outcome measures: Sex-specific trends in mean LVM (and its components, LV diastolic diameter (LVDD) and LV wall thickness (LVWT)), and LVM indexed to body surface area (BSA). Results: In men, age-adjusted LVM modestly increased from examination 4 to 8 (192 g to 198 g, p-trend=0.0005), whereas, in women it decreased from 147 g at examination 4 to 140 g at examination 8 (p-trend<0.0001). The trend for increasing LVM in men tracked with an increasing LVDD (p-trend=0.0002), whereas the decline in LVM in women was accompanied by a decrease in LVWT (p-trend<0.0001). Indexing LVM to BSA abolished the increasing trend in men (p-trend=0.49), whereas, the decreasing trend in women was maintained. Conclusions: In our longitudinal analysis of a large community-based sample spanning two decades, we observed sex-related differences in trends in LVM, with a modest increase of LVM in men (likely attributable to increasing body size), but a decrease in women. Additional studies are warranted to elucidate the basis for these sex-related differences

Large-Scale Candidate Gene Analysis of HDL Particle Features

Background: HDL cholesterol (HDL-C) is an established marker of cardiovascular risk with significant genetic determination. However, HDL particles are not homogenous, and refined HDL phenotyping may improve insight into regulation of HDL metabolism. We therefore assessed HDL particles by NMR spectroscopy and conducted a large-scale candidate gene association analysis. Methodology/Principal Findings: We measured plasma HDL-C and determined mean HDL particle size and particle number by NMR spectroscopy in 2024 individuals from 512 British Caucasian families. Genotypes were 49,094 SNPs in >2,100 cardiometabolic candidate genes/loci as represented on the HumanCVD BeadChip version 2. False discovery rates (FDR) were calculated to account for multiple testing. Analyses on classical HDL-C revealed significant associations (FDR<0.05) only for CETP (cholesteryl ester transfer protein; lead SNP rs3764261: p = 5.6*10(-15)) and SGCD (sarcoglycan delta; rs6877118: p = 8.6*10(-6)). In contrast, analysis with HDL mean particle size yielded additional associations in LIPC (hepatic lipase; rs261332: p = 6.1*10(-9)), PLTP (phospholipid transfer protein, rs4810479: p = 1.7*10(-8)) and FBLN5 (fibulin-5; rs2246416: p = 6.2*10(-6)). The associations of SGCD and Fibulin-5 with HDL particle size could not be replicated in PROCARDIS (n = 3,078) and/or the Women's Genome Health Study (n = 23,170). Conclusions: We show that refined HDL phenotyping by NMR spectroscopy can detect known genes of HDL metabolism better than analyses on HDL-C

Association of Common Polymorphisms in GLUT9 Gene with Gout but Not with Coronary Artery Disease in a Large Case-Control Study

BACKGROUND: Serum uric acid (UA) levels have recently been shown to be genetically influenced by common polymorphisms in the GLUT9 gene in two genome-wide association analyses of Italian and British populations. Elevated serum UA levels are often found in conjunction with the metabolic syndrome. Hyperuricemia is the major risk factor for gout and has been associated with increased cardiovascular morbidity and mortality. The aim of the present study was to further elucidate the association of polymorphisms in GLUT9 with gout and coronary artery disease (CAD) or myocardial infarction (MI). To test our hypotheses, we performed two large case-control association analyses of individuals from the German MI Family Study. METHODS AND FINDINGS: First, 665 patients with gout and 665 healthy controls, which were carefully matched for age and gender, were genotyped for four single nucleotide polymorphisms (SNPs) within or near the GLUT9 gene. All four SNPs demonstrated highly significant association with gout. SNP rs6855911, located within intron 7 of GLUT9, showed the strongest signal with a protective effect of the minor allele with an allelic odds ratio of 0.62 (95% confidence interval 0.52-0.75; p = 3.2*10(-7)). Importantly, this finding was not influenced by adjustment for components of the metabolic syndrome or intake of diuretics. Secondly, 1,473 cases with severe CAD or MI and 1,241 healthy controls were tested for the same four GLUT9 SNPs. The analyses revealed, however, no significant association with CAD or with MI. Additional screening of genome-wide association data sets showed no signal for CAD or MI within the GLUT9 gene region. CONCLUSION: Thus, our results provide compelling evidence that common genetic variations within the GLUT9 gene strongly influence the risk for gout but are unlikely to have a major effect on CAD or MI in a German population

The early repolarization pattern: Echocardiographic characteristics in elite athletes

Background The electrocardiographic early repolarization (ER) pattern is associated with idiopathic ventricular fibrillation and increased long-term cardiovascular mortality. Whether structural cardiac aberrations influence the phenotype is unclear. Since ER is particularly common in athletes, we evaluated its prevalence and investigated predisposing echocardiographic characteristics and cardiopulmonary exercise capacity in a cohort of elite athletes. Methods A total of 623 elite athletes (age 21 +/- 5 years) were examined during annual preparticipation screening from 2006 until 2012 including electrocardiography, echocardiography, and exercise testing. ECGs were analyzed with focus on ER. All athletes participated in a clinical follow-up. Results The prevalence of ER was 17% (108/623). ER-positive athletes were predominantly male (71%, 77/108), showed a lower heart rate (57.1 +/- 9.3 bpm versus 60.0 +/- 11.2 bpm; p = 0.015) and a higher lean body mass compared to ER-negative participants (88.1% +/- 5.6% versus 86.5% +/- 6.3%; p = 0.015). Echocardiographic measurements and cardiopulmonary exercise capacity in male and female athletes with and without ER largely showed similar results. Only the notching ER subtype (n = 15) was associated with an increased left atrial diameter (OR 7.01, 95%CI 1.65-29.83; p = 0.008), a higher left ventricular mass (OR 1.02, 95%CI 1.00-1.03; p = 0.038) and larger relative heart volume (OR 1.01, 95%CI 1.00-1.01; p = 0.01). During a follow-up of 7.4 +/- 1.5 years, no severe cardiovascular event occurred in the study sample. Conclusions In elite athletes presence of ER is not associated with distinct alterations in echocardiography and cardiopulmonary exercise. Athletes presenting with ER are rather male, lean with a low heart rate

Persistent Atrial Fibrillation in Elderly Patients: Limited Efficacy of Pulmonary Vein Isolation

(1) Background: Cryoballoon pulmonary vein isolation (cryoPVI) is established for symptomatic paroxysmal atrial fibrillation (AF) treatment, but its value in persistent AF is less clear. In particular, limited data are available on its efficacy in elderly patients (≥75 years) with persistent AF. Age is an important modifier of AF progression and represents a risk-factor for AF recurrence. (2) Methods: Prospective, single-center observational study to evaluate the impact of age on efficacy and safety of cryoPVI in elderly patients. Primary efficacy endpoint was symptomatic AF recurrence after 90-day blanking period. Primary safety endpoints were death from any cause, procedure-associated complications or stroke/transient ischemic attack. Median follow-up was 17 months (range 3–24). (3) Results: We included 268 patients with persistent AF (94 ≥ 75 years of age). Multivariate Cox regression analysis identified age as the only independent factor influencing AF recurrence in the overall cohort (p = 0.006). To minimize confounding bias in efficacy and safety analysis of cryoPVI, we matched younger and elderly patients with respect to baseline characteristics. At 24 months, primary efficacy endpoint occurred in 13/69 patients p = 0.0004). No differences were observed in the occurrence of safety end points. (4) Conclusions: Elderly (≥75 years) patients with persistent AF undergoing cryoPVI had an approximately threefold higher risk of symptomatic AF recurrence than matched younger patients. Accordingly, other treatment modalities may be evaluated in this population

Cryoballoon pulmonary vein isolation for atrial fibrillation in obese patients: A non-inferiority analysis

Background: Patients with obesity are at higher risk of developing atrial fibrillation (AF) and benefit from radiofrequency ablation. Potentially, cryoballoon ablation (CBA) may be equally effective and safe in such patients. Methods: We conducted a prospective, single-center study to investigate whether CBA for pulmonary vein isolation is as effective and safe in obese patients as it is in non-obese controls. Primary efficacy endpoint was recurrence of AF, atrial flutter or atrial tachycardia after a 90-day blanking period. Safety endpoints were death, stroke or procedure-associated complications. Conduction of a subgroup analysis regarding the impact of additional diabetes was predefined in case the primary efficacy endpoint was met. The study was event driven and powered for noninferiority. Results: A total of 949 patients underwent CBA (251 obese with mean body-mass-index 33.5 ± 3 kg/m2 and 698 non-obese with mean body-mass-index 25.3 ± 3 kg/m2) during a 5-year recruitment period. Median follow-up was 15 months. The primary efficacy endpoint occurred in 78/251 obese and 247/698 non-obese patients (12-months Kaplan-Meier event-rate estimates, hazard ratio 0.79; 95% confidence interval [CI], 0.58 to 1.07; log-rank P = 0.0002 for noninferiority). No differences were observed in safety end point occurrence (P = 0.78). The occurrence of primary efficacy end point was found to be unaffected by the presence of diabetes in the prespecified subgroup analysis (log-rank P = 0.57). Conclusion: CBA is effective and safe in obese and DM patients. Weighing the high cardiovascular risk of obese patients against a reduction of cardiovascular events by early rhythm control, CBA should be offered to this patient population

Circulating vascular endothelial growth factor and the risk of cardiovascular events.

OBJECTIVE: To investigate the relation of circulating concentrations of vascular endothelial growth factor (VEGF) for the risk of developing cardiovascular disease (CVD) in a large community-based sample. METHODS: We prospectively assessed the relation of circulating VEGF concentrations with the incidence of CVD among 3041 Framingham Heart Study participants (mean age 63.4±11.1 years, 59% women). Multivariable Cox proportional hazards models were estimated adjusting for standard risk factors to VEGF quartiles to incident CVD. Restricted cubic splines were used to examine the linearity of the association. RESULTS: After a mean follow-up of 8.8 (±2.8) years, 527 individuals experienced a first CVD event. Compared with participants in the first VEGF quartile, individuals in the second VEGF quartile had a 34% increased risk for future CVD (HR 1.34, 95% CI 1.03 to 1.74; p value=0.03) and individuals in third quartile had a 59% higher risk (HR 1.59; 95% CI 1.23 to 2.05, p value=0.0003). Individuals in the highest VEGF quartile had a similar cardiovascular risk as compared with those in the lowest VEGF quartile (HR 1.18, 95% CI 0.91 to 1.53, p value=0.21). Evaluation of restricted cubic splines confirmed the nonlinear, inverted U-shaped relation of serum VEGF and CVD events (p CONCLUSIONS: Circulating VEGF concentrations exhibit a complex non-linear (inverted U-shaped) relation with the risk of developing CVD events, with the lowest risk experienced at the lower and upper end of the distribution. The underlying pathophysiological mechanisms remain to be elucidated