Fish oil treatment for kidney transplant recipients: a meta-analysis of randomized controlled trials

Calcineurin inhibitors have adverse effects that contribute to nephrotoxicity and cardiovascular risk profile, and these may be reduced by administration of fish oil. The aim of this review was to assess the benefits and harms of fish oil supplementation in kidney transplant recipients on a calcineurin inhibitor-based immunosuppressive regimen.

The Cochrane Controlled Trials Registry, MEDLINE, and EMBASE were searched for randomized controlled trials of fish oil treatment in kidney transplant recipients on a calcineurin inhibitor-based immunosuppressive regimen. Trials comparing fish oil to both placebo and statins were included. Data were extracted for patient and graft survival, acute rejection, calcineurin inhibitor toxicity, cardiovascular events, adverse effects, compliance, renal function, blood pressure, and lipid profile. Dichotomous outcomes were reported as relative risk and continuous outcome measures as weighted mean differences (WMD), with 95% confidence intervals.

Sixteen suitable trials were analyzed. Fish oil treatment was associated with a lower diastolic blood pressure (WMD 4.5 mmHg, P=0.004) and higher high-density lipoprotein (HDL) cholesterol (WMD 0.12 mmol/L, P=0.01) but did not affect the other outcomes. Fishy aftertaste and gastrointestinal upset were common but did not result in significant dropout. Fish oil effects on lipids were not significantly different than low-dose statins.

There is insufficient evidence from currently available randomized controlled trials to recommend fish oil therapy to improve renal function, rejection rates, and patient or graft survival. Improvements in HDL cholesterol and diastolic blood pressure were too modest to recommend routine use.