Outcome Predictive Value of Serum Ferritin in ICU Patients with Long ICU Stay

Abstract

Background and Objectives: The simplified interpretation of serum ferritin levels, according to which low ferritin levels indicate iron deficiency and high levels indicate hemochromatosis is obsolete, as in the presence of inflammation serum ferritin levels, no longer correlate with iron stores. However, further data are needed to interpret serum ferritin levels correctly in patients with ongoing inflammation. Our study aimed to assess serum iron and ferritin dynamics in patients with long intensive care unit (ICU) stay and the possible correlations with organ dysfunction progression and outcome. Materials and Methods: We conducted a prospective study in a university hospital ICU over six months. All patients with an ICU length-of-stay of more than seven days were enrolled. Collected data included: demographics, Sequential Organ Failure Assessment (SOFA) score, admission, weekly serum iron and ferritin levels, ICU length-of-stay and outcome. Interactions between organ dysfunction progression and serum iron and ferritin levels changes were investigated. Outcome predictive value of serum ferritin was assessed. Results: Seventy-two patients with a mean ICU length-of-stay of 15 (4.4) days were enrolled in the study. The average age of patients was 62 (16.8) years. There were no significant differences between survivors (39 patients, 54%) and nonsurvivors (33 patients, 46%) regarding demographics, serum iron and ferritin levels and SOFA score on ICU admission. Over time, serum iron levels remained normal or low, while serum ferritin levels statedly increased in all patients. Serum ferritin increase was higher in nonsurvivors than survivors. There was a significant positive correlation between SOFA score and serum ferritin (r = 0.7, 95% CI for r = 0.64 to 0.76, p < 0.01). The predictive outcome accuracy of serum ferritin was similar to the SOFA score. Conclusions: In patients with prolonged ICU stay, serum ferritin dynamics reflects organ dysfunction progression and parallels SOFA score in terms of outcome predictive accuracy.

Predicting the severity of disease progression in COVID-19 at the individual and population level: A mathematical model

“…A high level of ferritin, measure of stored iron, was found to be associated with severe disease in COVID-19 patients and was linked to high fatality rates in a 72 patient prospective study [33, 50, 51]. In another study on 39 patients, those with mild COVID-19 symptoms had lower levels of ferritin while those with moderate or severe symptoms expressed higher levels of ferritin [50].…”

A Comprehensive Review on Serum Ferritin as a Prognostic Marker in Intensive Care Units: Insights Into Ischemic Heart Disease

“…Research findings have established a robust correlation between serum ferritin levels and patient outcomes within ICU settings, where elevated levels often signal an unfavorable prognosis [ 22 , 23 ]. Observations of serum ferritin dynamics have revealed their capacity to mirror the progression of organ dysfunction and parallel the Sequential Organ Failure Assessment (SOFA) score, thereby offering valuable insights into disease severity and eventual outcomes [ 22 ]. Furthermore, serum ferritin has emerged as a reliable predictor of mortality among critically ill patients, furnishing healthcare providers with crucial prognostic information [ 23 , 24 ].…”

“…Prognostic significance: Elevated serum ferritin levels in ICU patients with prolonged stays have been consistently linked with adverse outcomes and increased mortality rates [ 22 ]. The dynamics of serum ferritin serve as indicators of the progression of organ dysfunction and exhibit a strong correlation with the SOFA score, thereby providing valuable prognostic information regarding patient outcomes [ 22 ]. Notably, the predictive accuracy of serum ferritin for patient outcomes rivals that of the SOFA score, underscoring its pivotal role as a prognostic marker in critically ill patients [ 22 ].…”

“…Clinical implications: Serum ferritin levels are valuable indicators of inflammation, tissue damage, and cellular injury among ICU patients, offering critical insights into disease severity and potential outcomes [ 3 , 22 ]. In conditions such as sepsis, elevated serum ferritin levels have been consistently associated with poorer outcomes, thus highlighting its utility as a biomarker for disease severity and prognosis [ 3 ].…”

“…Iron metabolism and disease: Abnormal serum ferritin levels extend beyond ICU settings and have been implicated in various diseases, including inflammatory disorders, cardiovascular diseases (CVDs) such as myocardial infarction and coronary artery disease, hepatic disorders, neurological disorders, metabolic disorders, and immune disorders [ 3 , 22 ]. Given this wide-ranging association, monitoring iron metabolism through serum ferritin assessment is critical in risk assessment, disease management, and predicting outcomes among critically ill patients [ 3 ].…”