Impact of worsening renal function during the treatment of decompensated heart failure on changes in renal function during subsequent hospitalization

Background Worsening renal function (WRF) commonly complicates the treatment of acute decompensated heart failure. Despite considerable investigation in this area, it remains unclear to what degree WRF is a reflection of treatment-versus patient-related factors. We hypothesized that if WRF is significantly influenced by factors intrinsic to the patient, then WRF during an index hospitalization should predict WRF during subsequent hospitalization. Methods Consecutive admissions to the Hospital of the University of Pennsylvania with a discharge diagnosis of congestive heart failure were reviewed. Patients with > 1 hospitalization were retained for analysis. Results In total, 181 hospitalization pairs met the inclusion criteria. Baseline patient characteristics demonstrated significant correlation between hospitalizations (P >= .002 for all) but minimal association with WRF. In contrast, variables related to the aggressiveness of diuresis were weakly correlated between hospitalizations but significantly associated with WRF (P <= .024 for all). Consistent with the primary hypothesis, WRF during the index hospitalization was strongly associated with WRF during subsequent hospitalization (odds ratio [OR] 2.7, P = .003). This association was minimally altered after controlling for traditional baseline characteristics (OR 2.5, P = .006) and in-hospital treatment-related parameters (OR 2.8, P = .005). Conclusions A prior history of WRF is strongly associated with subsequent episodes of WRF, independent of in-hospital treatment received. These results suggest that baseline factors intrinsic to the patient's cardiorenal pathophysiology have substantial influence on the subsequent development of WRF. (Am Heart J 2011; 161: 944-9.)