ELOVL2-methylation and renal and cardiovascular event in patients with chronic kidney disease

Abstract

Background: Methylation of the Elongation Of Very Long Chain Fatty AcidsLike 2 (ELOVL2) gene promoter may predict premature ageing and cardiovascular risk. Methods: We studied the cross-sectional associations between blood ELOVL2- methylation and cardiovascular risk factors in 350 patients with chronic kidney disease (CKD) stage G2–G4 aged between 22 and 90 years. In a follow-up study for a mean of 3.9 years, we investigated the association between baseline ELOVL2- methylation and renal or cardiovascular events including death. Results: ELOVL2-methylation at seven CpG cites increased with age (the correlation coefficients between 0.67 and 0.87, p<0.001). The ELOVL2-CpGs methylation was lower in patients with CKD stage G2 versus those in stage G3a, G3b and G4, but the differences were explained by age. ELOVL2-CpGs methylation showed no correlations with cardiovascular risk factors after adjusting for age. During the follow-up, 64 patients showed deterioration in renal function or died and 77 showed cardiovascular events or died. The hazard ratio and 95% confidence intervals for renal or cardiovascular events according to baseline ELOVL2- CpGs methylation were not significant after adjustment for covariates. Conclusions: ELOVL2-hypermethylation showed a strong association with age, but was not independently associated with cardiovascular risk factors or with future renal or cardiovascular events in patients with CKD. ELOVL2 gene methylation is not likely to be itself a cause for ageing or illnesses, but it could be rather influenced by other upstream processes that deserve investigation.