Nephrology Consultation Patterns and Clinical Outcomes in Hospitalized Patients with Heart Failure.

BACKGROUND: Kidney dysfunction frequently complicates heart failure hospitalization and is associated with adverse outcomes, complicating inpatient management. However, nephrology consultation practices in hospitalized patients with heart failure remain incompletely characterized. METHODS: We conducted a retrospective cohort study of adults hospitalized with a primary diagnosis of heart failure at a tertiary care center in Puerto Rico between January 1, 2021, and December 31, 2023. Nephrology consultation patterns, including timing, were evaluated. Outcomes included in-hospital mortality, length of stay, and 90-day readmission. Descriptive and exploratory analyses were performed. RESULTS: A total of 991 hospitalizations were analyzed. Mean age was 73 years, and 42% were female. Chronic kidney disease was present in 27% of patients, and acute kidney injury in 16%. Nephrology consultation occurred in 38% of hospitalizations, including 76% of patients with acute kidney injury and 73% with chronic kidney disease. Consultation rates were higher with increasing baseline serum creatinine, reaching 97% in patients with creatinine ≥3.0 mg/dL. Length of stay differed significantly across consultation groups (5.6, 8.3, and 12.2 days; P < 0.001). In-hospital mortality was 9%. Unadjusted mortality was higher among consulted patients (OR, 3.74; 95% CI, 2.48-5.90; P < 0.001). Exploratory adjusted analyses incorporating measured kidney-related variables were consistent with substantial confounding and should be interpreted cautiously because key measures of illness severity were unavailable. Ninety-day readmission occurred in 40% of hospitalizations and did not differ by consultation status. CONCLUSIONS: Nephrology consultation occurred in fewer than half of hospitalizations and was more common in patients with advanced kidney dysfunction; however, a significant proportion of patients with acute kidney injury or chronic kidney disease did not receive consultation. These findings highlight variability in nephrology consultation practices and referral patterns in hospitalized patients with heart failure and kidney dysfunction.