Background: Diabetic nephropathy, a major complication of diabetes, is the primary risk factor for dialysis, cardiovascular diseases, and mortality. Dietary fatty acids (FAs) have been revealed to be related with cardiovascular diseases in the general populations. The aim of this study was to investigate the association of circulating FAs with diabetic nephropathy.
Methods: In this cross-sectional study, 190 Japanese patients with type 2 diabetes were included. Circulating FAs were measured by gas chromatography-mass spectrometry. Spearman rank correlation coefficients were used to investigate the association between the logarithm of FAs and the logarithm of urinary albumin excretion (UAE). We have performed logistic regression analysis to determine the effect of FAs on the presence of macroalbuminuria, defined as UAE value ≥300 mg/g creatinine.
Results: Mean age, body mass index, and duration of diabetes were 62.7 ± 12.1 years, 25.0 ± 4.5 kg/m2, and 9.8 ± 8.7 years, respectively. In total, 26 patients were diagnosed with macroalbuminuria. The logarithm of circulating arachidonic acid (AA) was negatively associated with the logarithm of UAE (r = - 0.221, p = 0.002). Additionally, circulating AA in patients with macroalbuminuria was lower than that in patients without macroalbuminuria (112.3 ± 75.3 mg/day vs. 164.8 ± 66.0 mg/day, p < 0.001). The logarithm of circulating AA was associated with the presence of macroalbuminuria after adjusting for covariates (odds ratio of Δ1 incremental: 0.32, 95% confidence interval: 0.10-0.99, p = 0.042).
Conclusions: Circulating AA was negatively associated with UAE and the presence of macroalbuminuria.
Keywords: Arachidonic acid; Cohort study; Diabetic nephropathy; Epidemiology; Fatty acids.