Worsening renal function in patients admitted with congestive heart failure: prevalence, risk profile, and hospital readmissions

Introduction Renal function is often negatively impacted in patients with Congestive Heart Failure (CHF) due to the interplay between the heart and kidneys. Worsening Renal Function (WRF) has been associated with decreased survival, accelerated CHF progression, and higher hospitalization rate. Previous literature has thoroughly documented the effects of CHF on hospital readmissions; however, few studies have examined the impact of WRF on CHF during hospitalization, particularly not in a vulnerable population. Thus, the aim of this study was to determine the prevalence, clinical predictors, and short-term hospital readmissions of WRF among hospitalized CHF patients. Methods This was a retrospective chart review utilizing the data of 297 patients hospitalized for CHF from 2019 to 2020, either due to an exacerbation of symptoms or new-onset of disease. The analysis of our study centered around identifying the risk factors and 30-day hospital readmission rates of patients with WRF, defined as an increase in serum creatinine of ≥ 0.3 mg/dL from admission, in comparison to patients who did not develop WRF. The significance between the two groups was measured using Fisher's Exact test, Wilcoxon rank-sum, and chi-square analysis. A risk score calculated from the sum of point values assigned to each independent risk factor was created. Results Data shows that 27% of hospitalized CHF patients developed WRF. Patients with WRF had a significantly longer hospital stay and a significantly higher increase in daily Creatinine values. We identified old age, overweight, type 2 diabetes (T2D), chronic kidney disease not on dialysis, and high Furosemide dose (oral and intravenous) as independent risk factors. Other independent risk factors include abnormally high serum levels of ProBNP (≥ 9,000 ng/dL), troponin T ≥ (0.04 ng/mm), and Creatinine (≥ 1.5 mg/dL). Based on this data, a point score reflected that patients with a 6+ risk score were four times more likely to develop WRF than patients with a risk score of 0. There was no association between WRF and higher 30-day readmissions. Conclusions WRF is common in hospitalized CHF patients. Although WRF was not associated with an increased 30-day hospital readmission rate, it was associated with longer hospital length of stay and thus increased economic burden. These results highlight the benefits of implementing in-care changes to address the particular risk factors associated with WRF to prevent further progression of renal impairment in hospitalized HF patients. Future directions will incorporate other outcome variables that discern the long-term implications of WRF, including 5-year readmission rates, ESKD, and mortality.