The relationship between serum uric acid/albumin ratio and phosphorus and EARLY mortality in patients with and without acute kidney injury admitted to the internal medicine intensive care unit

Acute kidney injury (AKI) is a condition characterised by sudden loss of renal function that occurs within hours to days and results in irregular fluid-electrolyte and acid-base homeostasis. Today, the need for intensive care has increased due to prolonged life expectancy and increasing comorbid diseases. With this increasing need, methods to predict mortality and morbidity have been needed and various scoring systems have been used. In our study, we included a total of 1016 patients admitted to the Internal Medicine Intensive Care Unit of Eskişehir Osmangazi University Faculty of Medicine Hospital between 01.05.2020 and 01.11.2021. We tried to reveal the relationship between serum uric acid/albumin ratio and phosphorus on mortality by evaluating patients with and without AKI separately. Since we thought that indiscriminate evaluation of patients would change the general average, we aimed to show the relationship of uric acid and phosphorus, which we expected to be high in AKI, with mortality in patients without acute kidney injury. In our study, we found that serum uric acid/albumin ratio was associated with 28 day mortality in both patients with AKI (n=449) and patients without AKI (n=567). The best cut-off value of serum uric acid/albumin ratio associated with 28 day mortality was 3.59 mg/g in patients with AKI and 2.28 mg/g in patients without AKI. We found that high serum phosphorus value was associated with 28 day mortality in patients with AKI, but no significant difference was found between hyperphosphatemia and mortality in patients without AKI. In our study, serum uric acid/albumin ratio and phosphorus were correlated with 28 day mortality and APACHE-II score both in patients with and without AKI. In our study, we concluded that serum uric acid/albumin ratio can be used as an indicator of early mortality even in the absence of AKI at presentation. Key words: acute kidney injury, intensive care unit, serum uric acid, albumin, phosphorus