Abstract 15174: Higher Plasma Osmolality as an Independent Determinant of In-hospital Worsening Renal Function in Acute Decompensated Heart Failure

Backgrounds: Previous studies showed that worsening renal function (WRF) was associated with poor clinical outcome in acute decompensated heart failure (ADHF) patients. Hyperosmolarity is known to cause direct renal cell injury and decreases in renal blood flow and glomerular filtration rate. In ADHF setting, the plasma osmolality can be changed dramatically. However, the prognostic significance of plasma osmolality for the development of WRF in ADHF patients is unclear. Methods: We examined 320 consecutive ADHF patients who admitted to our institution between January 2013 and January 2014 from prospective registry. Patients who had acute coronary syndrome and without complete data-set at admission were excluded. Finally, 303 patients were divided into two groups according to lower plasma osmolality (below 297 mOsm/kg H2O, the cut-off value based on ROC analysis) or higher plasma osmolality (above 297 mOsm/kg H2O) at admission. WRF was defined as ≥ 0.3 mg/dl increase in serum creatinine from baseline to discharge. Results: During follow-up period (median 21 days, interquartile range 14-29), WRF was occurred in 58 patients (19.6 %). Patients with higher plasma osmolality had significantly higher incidence of WRF compared with those without (32.3% vs 13.6%, P<0.01). Higher plasma osmolality was associated with more use of diuretics, higher serum creatinine level and lower hemoglobin level. There were no significant differences between the two groups in terms of age, sex, body mass index, NYHA functional class, left ventricular ejection fraction (LVEF), blood pressure, etiology of HF, cardiovascular medications other than diuretics, plasma brain natriuretic peptide (BNP) level on admission. Multivariate logistic regression analyses showed that higher plasma osmolality (OR 2.00, 95% CI 1.00-3.98, P=0.049), as well as lower hemoglobin (OR 1.22, 95% CI 1.04-1.42, P=0.012), was an independent determinant of WRF, although other variables including age, sex, serum creatinine level and use of diuretics on admission were not. Conclusions: In patients with ADHF, higher plasma osmolality on admission was an independent predictor of in-hospital WRF, suggesting the measurement of plasma osmolality might be useful for identifying patients at risk for WRF.