Serum Zinc and Selenium Levels in ICU Patients: Association with Disease Severity and Nutritional Status

ObjectivePatients hospitalized in the intensive care unit are usually under stress due to severe diseases and infections, which may lead to a decrease in the level of micronutrients in them. Among micronutrients, the assessment of serum selenium and zinc status in critically ill patients is of great importance, because these two minerals play a vital role in maintaining health and immune system function. Therefore, this study examines the status of serum zinc and selenium in adults hospitalized in the special care department of Baath Hospital in 2024. Material and MethodsThis cross-sectional study was conducted in Besat Hospital, Hamadan, during 2024 after approval by the Ethics Committee of Hamadan University of Medical Sciences. 72 patients hospitalized in the intensive care unit of Besat Hospital were selected through convenience sampling. Inclusion criteria for the study included being over 18 years of age and having been hospitalized in the ICU for one week. Written informed consent was obtained from patients or their companions for sample collection. Serum zinc and zinc levels and other laboratory factors were measured. Also, demographic and hospital information of the patient including name, age, and sex of the patient, date of hospitalization, cause of hospitalization, severity of the disease, nutritional method, duration of nutritional interruption, and outcome of the disease were recorded in the checklist. Analyses were performed using the nonparametric Mann-Whitney test, analysis of variance, and Spearman correlation test using Stata 17.0 software at a significance level of 0.05. ResultsAccording to the results, 70.8% of the patients were male and 29.2% were female, and the mean age of the patients was 54.90 years. 80.6% of the patients were on enteral nutrition (EN) and 15.3% were on oral nutrition. According to the results, 52.8% of the patients admitted to the ICU were discharged and 47.2% died. The mean serum zinc level was 15.74 micrograms/dL, of which 3.40% were zinc deficient. The mean serum selenium level was 19.97 nanograms/mL, and it was normal in 6.98% of the patients. Also, there was no statistically significant relationship between disease severity, hospital outcome, feeding interruption, feeding method, serum zinc and selenium levels in patients admitted to the ICU (p > 0.05). The mean serum zinc level based on the APACHE score showed that patients in the more severe stage of the disease had lower serum zinc levels. The mean serum zinc level in patients with APACHE score 20-30 was 71.56 micrograms/dL. The mean serum zinc level in enteral feeding patients was 74.38 and in oral feeding patients was 75.36 micrograms/dL. Also, the mean serum selenium level in enteral feeding patients was 97.25 and in oral feeding patients was 97.71 nanograms/mL. ConclusionThe present study shows that zinc deficiency is significant in patients hospitalized to the intensive care unit but is not associated with disease severity, type of nutrition, interruption of nutrition, and final patient outcome. However, further studies with a larger sample size of patients are needed to draw definitive conclusions.