Dietary supplementation with fish oil modifies renal reserve filtration capacity in postoperative, cyclosporin A-treated renal transplant recipients

The effect of a daily supplementation of 6 g fish oil (30% C20:5 omega-3 = EPA and 20% C22:6 omega-3 = DHA) for 1 month on renal function variables was investigated in a placebo-controlled (6 g coconut oil), prospective, randomized, double-blind study in acute postoperative cyclosporin A (CyA)-treated renal transplant recipients. Seventeen patients ingested placebo capsules (EPA-) and 14 patients fish oil (EPA+). Renal function tests were performed using the simultaneous determination of 125I-iothalamate and 131I-hippuran clearances for glomerular filtration rate (GFR) and effective renal plasma flow (ERPF), respectively. Renal reserve filtration capacity was assessed by dopamine infusion, amino acid infusion, and a combination of both stimuli. After 1 month there were no significant differences in rejection episodes, CyA dose, or CyA levels. In contrast to our earlier observations, serum creatinine, creatinine clearance, GFR, and ERPF did not differ between the EPA- and EPA+ groups. Filtration fraction (FF) differed significantly, being 0.21 in the EPA- group versus 0.26 in the EPA+ group. To exclude the possible influence of a rejection episode, the nonrejecting patients were analyzed separately, creating the subgroups EPA + re - and EPA - re -. These two groups were comparable in age, donor age, and GFR. The EPA + re-group had a significantly lower ERPF (164 ml/min per 1.73 m2) than the EPA-re- group (262 ml/min per 1.73 m2). FF was significantly higher in the EPA+ re-group (0.26) than in the EPA-re-group (0.21).(ABSTRACT TRUNCATED AT 250 WORDS)