Neuropeptide Y receptor Y2 gene polymorphism interacts with plasma neuropeptide Y levels in predicting left ventricular hypertrophy in dialysis patients

BACKGROUND: Neuropeptide Y (NPY) is a sympathetic neurotransmitter that acts on multiple receptors involved in cardiovascular remodelling and angiogenesis. Plasma levels of NPY are increased in patients with end-stage renal disease (ESRD) and are independently related to left ventricular hypertrophy (LVH) and incident cardiovascular events in these patients. OBJECTIVE: To investigate the relationship between NPY receptor Y2 gene polymorphism and left ventricular mass index (LVMI) as well as the interaction between this polymorphism and plasma NPY in determining LVH in 189 ESRD patients. RESULTS: LVMI was significantly higher (+12%, P = 0.03) in patients carrying the C allele than in those without C allele and was linearly associated with plasma NPY (P = 0.01). Interaction analysis showed a significant NPY-LVMI relationship in patients with the C allele, both at univariate (r = 0.27, P = 0.001) and multivariate (r = 0.21, P = 0.01) analyses, whereas no such relationship existed in patients without this allele. In fully adjusted analyses, a 10 pmol/l increase in plasma NPY entailed a 4.9 g/m increase in LVMI in patients with C allele, whereas the same change in NPY levels did not modify the NPY-LVMI link in patients without such allele (P = 0.009). CONCLUSION: NPY receptor Y2 polymorphism is independently associated with LVMI and interacts with plasma levels of NPY in explaining the variability of LVH in ESRD. These results offer a genetic basis to the hypothesis that NPY is causally implicated in the pathogenetic pathway leading to LVH in ESRD patients.