Dietary Acid Load and Glomerular Filtration Rate in Chronic Kidney Patients: A Study From South West of Iran
Abstract
Background: Kidney diseases are prevalencing rapidly and -nutri tional transition has increased the Dietary Acid Load (DAL) of diet and thus exacerbating the metabolic disorders. The goal of the study was to determine the association the DAL of the diet with certain renal function indices in Chronic Kidney Disease (CKD) patients.
Methods: In this cross-sectional study, 90 CKD patients were recruited. The DAL index, including the Potential Renal Acid Load (PRAL), Net Endogenous Acid Production (NEAP), and Net Acid Excretion (NAE) was calculated using data from a Food Frequency Questionnaire (FFQ) and adjusted for energy variables. Ultimately, their correlation with anthropometric and biochemical indices, such as Glomerular Filtration Rate (GFR) and Creatinine (Cre) was estimated.
Results: Median and Interquartile range (IQR) of DAL forĀ participants was 13.9(8.9-20.9), 47.1(39.3-52.12) and 55.8(50.16-61.9) mEq/day for PRAL, NEAP, and NAE, respectively, with a strong correlation (p<0.001) among them. Age (p<0.05), total daily energy intake (p<0.05), percentage of protein and carbohydrates from energy (p<0.05), and GFR (p<0.05) were significantly higher in the third tertile compared to the T1 group of DAL indexes. However, Blood Urea Nitrogen (BUN) (p<0.05) and Cre (p<0.05) were lower.
After adjustment in the General Linear Model, the Mean difference (MD) of GFR and Cre became nonsignificant. Nevertheless, in the crude model, the MD of GFR and Cre were significant (p<0.05).
Conclusion: By adjusting the effect of confounding variables, DAL indics of CKD patient did not show significant correlation with renal function. Long-term studies involving larger populations and consideration of confounding factors are recommended.