Trans-fatty Acids and Survival in Renal Transplantation

OBJECTIVE: High consumption of trans-fatty acids (TFAs) is associated with increased mortality.

DESIGN AND METHODS: Observational cohort study of 1.988 Norwegian renal transplant recipients with a median follow-up time of 9.6 years. We assessed multivariable adjusted associations between plasma levels of industrial and ruminant TFAs with patient and graft survival. Plasma phospholipid fatty acid levels were determined by gas chromatography at 10 weeks after transplantation.

RESULTS: During follow-up, there were 595 deaths, and 805 grafts were lost. Plasma industrial TFA levels dropped from 0.3 wt% in years 1999-2004 to reach a plateau of 0.2 wt% from year 2005 and beyond, whereas plasma levels of ruminant TFAs remained stable throughout the study period. In the former era (years 1999 to 2004, n = 902), we found multivariable adjusted associations between plasma industrial TFA levels and mortality (hazard ratio 4.44, P = .02) and graft loss (hazard ratio 4.22, P = .01). In the latter era (years 2005 to 2011, n = 1,086), there were no associations between plasma industrial TFA levels and patient or graft survival. Plasma ruminant TFAs were not associated with mortality or graft loss in either eras.

CONCLUSION: In this Norwegian transplant cohort, plasma industrial TFA levels dropped from around 0.3 wt% in the former era to 0.2 wt% in the latter era. While plasma industrial TFA was significantly associated with survival in the former era, no associations were found with survival in the latter era. This finding suggests that lowering industrial TFA consumption from modest to low levels could possibly influence health beneficially after renal transplantation.