The association between serum ferritin level, microalbuminuria and non-alcoholic fatty liver disease in non-diabetic, non-hypertensive men

Background: Iron-mediated cell injury may cause glomerular endothelial dysfunction, which precedes microalbumuria. However, there have been no reports on the relationship between serum ferritin level and microalbuminuria. The aim of this study is to assess the relationship between serum ferritin level and microalbuminuria in apparently healthy men and to evaluate how non-alcoholic fatty liver disease (NAFLD) affects this association. Methods: Microalbuminuria and serum ferritin level were measured, and hepatic ultrasound was performed in a sample of 2489 non-diabetic, non-hypertensive men. The patients were classified into two groups according to urinary albumin-creatinine ratio (UACR) in morning urine specimens: normoalbuminuria (<30 mu g/mg) and microalbuminuria (30-300 mu g/mg). Results: The overall prevalence of microalbuminuria and NAFLD based on ultrasound findings were 4.5% (113 subjects) and 41.9% (1042 subjects), respectively. The microalbuminuric group had significantly higher levels of serum ferritin than the normoalbuminuric group (255.4 pmol/L versus 207.5 pmol/L, p < 0.001). In the multivariate regression analysis, serum ferritin level was independently associated with microalbuminuria irrespective of multiple covariates (OR [95% CI] 1.746 [1.221-2.497]). Subgroup analyses according to NAFLD revealed that the NAFLD group had higher serum ferritin level and a higher prevalence of microalbuminuria compared with the non-NAFLD group (233.8 pmol/L versus 194.3 pmol/L, p < 0.001) (6.3% versus 3.2%, p < 0.001). However, in the multivariate regression analysis, there was a significant association between serum ferritin level and microalbuminuria in both the non-NAFLD and the NAFLD group. Conclusions: Our results indicate that serum ferritin level is associated with microalbuminuria in non-hypertensive, non-diabetic men, irrespective of NAFLD.