Abstract
Background: Cardiovascular disease (CVD) is the leading cause of death worldwide. Risk stratification of CVD patients may be improved by predictive biomarkers, including genetic markers. Elevated circulating vascular endothelial growth factor A (VEGF-A) levels have been linked to CVD development. We explored whether single nucleotide polymorphisms (SNPs) at the VEGFA locus on human chromosome 6 were associated with VEGF-A levels and clinical outcomes in established CVD. VEGF-A levels were compared between coronary heart disease patients and heart healthy controls.
Methods: Imputed genotypes of 30 SNPs from the VEGFA region for 1935 patients from the Coronary Disease Cohort Study (CDCS) and 1183 individuals from the Canterbury Healthy Volunteers Study (HVOL) were analysed for associations with cardiometabolic parameters. Association with clinical endpoints was assessed using Kaplan-Meier analysis and multivariate regression models. To validate the findings from imputed data, DNA samples of 2027 CDCS patients and 227 HVOL participants were manually genotyped for variants rs6921438 and rs7767396. Baseline plasma VEGF-A assayed by ELISA in 227 HVOL participants was compared with levels in 549 CDCS patients.
Results: Manual genotyping showed rs6921438 AA and rs7767396 GG genotype groups had lower VEGF-A levels at baseline (CDCS: rs6921438 AA (27.7 pg/mL), AG (43.3 pg/mL), GG (63.2 pg/mL), p = 4.49 × 10- 22; rs7767396: GG (27.4 pg/mL), AG (42.8 pg/mL), AA (61.5 pg/mL) p = 3.47 × 10- 21; HVOL rs6921438 AA (12.8 pg/mL), GA (19.9 pg/mL), GG (26.4 pg/mL) p = 0.021; rs7767396 GG (12.6 pg/mL), AG (19.6 pg/mL), AA (25.9 pg/mL) p = 0.029). In the CDCS cohort rs6921438 AA was associated with increased risk of all-cause death (p = 0.03); non ST-elevated myocardial infarction (NSTEMI, p = 0.0003), heart failure (HF, p = 0.035) and major adverse cardiovascular events (p = 0.032); rs7767396 GG was associated with increased NSTEMI (p = 0.001) and HF (p = 0.023) risk; rs6921438 AA (Hazard Ratio (HR) = 6.55 p = 0.017), rs7767396 GG (HR = 0.149, p = 0.017) and VEGF-A (HR = 2.55, p = 0.018) were independent HF admission risk predictors.
Conclusions: Variants rs6921438 and rs7767396 are associated with plasma VEGF-A levels. Both SNPs and VEGF-A may be useful in prognosis for HF after acute coronary events.