The aim of the present study was to evaluate the association between heart failure (HF) and chronic kidney disease (CKD) in tertiary care centers using the clinical records of patients enrolled in internal medicine departments.

We used the clinical records of 1380 elderly patients to identify patients with a history of HF and CKD using admission ICD codes and glomerular filtration rate (GFR) formulas. Magnitude and strength of such associations were investigated by univariable and multivariable analysis.

Of the 1380 patients enrolled, 27.9% had HF (age 80±7, BMI 27±6 kg/m²) and 17.4% CKD (age 81±7, BMI 26.8±6kg/m²). Both groups were significantly older (P<0.0001) with BMI higher than the patients without those diagnosis (P<0.02). Patients with a history of CKD showed higher non-fasting glycaemia (140±86 vs. 125±63mg/dL, P<0.001). CKD was significantly associated with HF (P<0.0001). Patients with HF had an estimated GFR lower than patients without HF (P<0.0001). Comorbidity and severity indices were significantly higher in subjects with HF (P<0.0001) and CKD (P<0.0001) than in those without. Multivariable analysis showed a significant association between HF and age (for five years increase OR 1.13, P<0.009), BMI (for each 3 kg/m² increase OR 1.15, P<0.001), GFR (for each decrease of 10mL/min increase OR 0.92, P<0.002) and severity index (IS) (for each 0.25 units increase OR 1.43, P<0.001).

HF on admission is strongly associated with CKD, older age, BMI, and SI. These data focus the value of epidemiological studies such REPOSI in identifying and monitoring multimorbidity in elderly.