Nutritional Status and Clinical Outcomes of Adult Intensive Care Unit(ICU) Patients -- a systematic review and Meta-analysis

Background: The severity of the illness and the inability to eat while in the intensive care unit put ICU patients at a high risk of malnutrition. Nutritional status assessment is vital for managing patients’ morbidity, length of stay, and mortality. This systematic review and meta-analysis aimed to assess the nutritional status of adult ICU patients and evaluate the influence of malnutrition on clinical outcomes. Methods The meta-analysis included studies focusing on nutritional status in adult ICU patients. The data extraction comprised the author's name, year of publication, sample size, and nutritional assessment tool used to classify patients as well-nourished and malnourished. Statistical analysis was performed using STATA 17 to determine the prevalence of overall malnutrition among the ICU patients, and a forest plot was generated to visually depict the pooled estimate and individual study results. Results: 31 articles were included in this meta-analysis with a sample size of 21,413 patients. The overall mortality was 1.446 (95% CI: 0.761 - 2.130), and those who were undernourished had a 44.6% increased risk of passing away. In addition, malnourished patients required 5.593 more days of ICU stay on average with a 95% confidence interval of [2.920, 8.265], a Z-value of 4.10, and a p-value of 0.0000; the pooled effect size of malnutrition was 32.74 (95% confidence interval: 19.9 to 45.5). Conclusion Malnutrition is prevalent among adult ICU patients, with wide variation across studies, and the situation gets worse after admission. Also, malnourished patients are having longer hospital stays and are more likely to die compared to well-nourished patients.