Distinct associations between dietary omega-3 and omega-6 fatty acids intake with chronic kidney disease in adults with and without diabetes: A cross-sectional study

Objective: We explored the relationship of dietary intake of fatty acids with chronic kidney disease (CKD) according to glycemic status in Japanese people. Methods: A total of 1031 participants aged ≥40 y were included in this population-based, cross-sectional study. A validated self-administered diet history questionnaire was used to measure the dietary intakes of fat and fatty acids, including omega-3 and omega-6 polyunsaturated fatty acids. CKD was defined as estimated glomerular filtration rate < 60 mL/min/1.73 m² and diabetes as the use of antidiabetic medication, fasting plasma glucose ≥ 126 mg/dL, or hemoglobin A_1c of ≥6.5%. Urine biomarkers of kidney injury (liver-type fatty acid–binding protein, β₂-microglobulin, and albumin) were also examined. Results: The mean age of the participants was 62.5 ± 11.2 y, and 482 (46.8%) of them were men. Overall, 177 (17.2%) participants had CKD. In the multivariable model, low omega-3 intake (odds ratio = 0.109; 95% CI, 0.019–0.645) and high omega-6–to–omega-3 ratio (odds ratio = 2.112; 95% CI, 1.167–3.822) were associated with CKD in participants with diabetes but not in those without. In selected participants with diabetes, a substantial trend of urinary liver-type fatty acid–binding protein and β₂-microglobulin level elevation along with an increase in the dietary ratio of omega-6 to omega-3 was observed. Conclusions: Low dietary omega-3 intake and high omega-6–to–omega-3 ratio were associated with CKD in middle-aged and older Japanese people with diabetes but not in those without diabetes. These results may provide insight into the more tailored approaches for dietary polyunsaturated fatty acids to prevent CKD.