88 The risk of AR early post-Tx is variable but unpredictable. Consequently, in practice most patients, irrespective of AR risk, receive similar doses of immunosuppressants. The goal of these studies was to search for variables that predict the risk for AR during the first year post-Tx. The study included 1641 first Tx recipients of LRD (N=446) or CAD renal grafts (N=1195) transplanted at one institution. Patients had no AR (54%) or had their first AR during the first year post-Tx (46%). By univariate analysis the occurrence of AR correlated with: CAD recipient (p=.0008); younger recipient (p<.0001); and higher average BP levels before the first AR (p<.0001). Systolic, diastolic and MAP correlated with the prevalence of AR (all p<.0001). HLA matching and PRA titers did not correlate with the risk of AR when CAD and LRD recipients were analyzed separately. By multivariate analysis the recipient age and the pre-AR BP correlated with the prevalence of AR (see figure). Increasing pre-AR BP levels also correlated with increasing numbers of AR and with earlier AR (both p<.0001). The correlation between BP and AR was independent of graft function and of recipient race. In contrast, the higher prevalence of AR in CAD compared to LRD could be explained, at least in part, by lower BP in LRD (p<.0001). Thus, there was no significant difference in the %AR between LRD and CAD matched for BP. BP post-Tx correlated with BP pre-Tx. However, the risk of AR correlated best with the BP post-Tx. Thus, the highest prevalence of AR was in patients with pre-Tx BP<150 mmHg and higher post-Tx BP (81% AR). In contrast, the lowest AR (22%) was in patients with pre-BP>150 and lower post-BP. Conclusion, elevated BP early post-Tx identify patients at high risk for AR independently from other variables. We postulate that post-Tx BP levels identify variables within the allograft, such as ischemic injury, that may be associated with high risk of AR.Figure