Mean arterial blood pressure while awaiting kidney transplantation is associated with the risk of primary nonfunction.

BACKGROUND: Primary nonfunction (PNF) is a devastating outcome after kidney transplantation and is more common with kidneys from donors without a heartbeat or expanded criteria donors, or both. We investigated recipient-based risk factors for PNF independent of organ donor source.

METHODS: We used a case-control study design and matched for the source of organ and year of transplantation; for each recipient with PNF, two recipients without PNF (controls) were randomly selected. We identified 20 PNF cases and 40 controls from our pool of 993 kidney transplant recipients who all received their transplants at our center between 2003 and 2008. The association between PNF and immune risk factors and blood pressure (BP) levels during the 3 months before transplantation was analyzed.

RESULTS: Among the factors analyzed, the mean systolic BP (P=0.003, Wilcoxon test), diastolic BP (P=0.02), and mean arterial pressure (MAP) (P=0.006) during the 3 months before transplantation were significantly lower in the PNF cases compared with the controls without PNF. In a multivariable model, only MAP remained as a significant risk factor for PNF and each 10 mm Hg decrease in MAP was associated with a 43% increased odds for PNF (P=0.01). The odds ratio for PNF in those with MAP less than or equal to 80 mm Hg was 4.32 (95% confidence interval, 1.41-13.2, P=0.008), compared with the group with MAP more than 100 mm Hg.

CONCLUSIONS: Our findings support the hypothesis that the average MAP less than or equal to 80 mm Hg during the 3 months before kidney transplantation is a risk factor for PNF.