Abstract

Background: Delirium is a common neuropsychiatric condition in ICU patients, particularly among older adults, and is strongly associated with poor clinical outcomes. However, predictors of delirium severity, especially hypoactive delirium, remain underexplored in the literature. This study aimed to identify predictors of delirium severity, including age, comorbidities, steroid use, and metabolic acidosis, while underscoring the clinical significance of hypoactive delirium.

Methods: This cross-sectional study included 160 ICU patients admitted from September 2016 to June 2017. Potential predictors such as age, steroid use, comorbidities,metabolic acidosis, and ventilator duration were evaluated. Delirium severity was assessed using the Delirium Index (DI).

Results: Multiple regression analysis showed that age ≥ 65 years, number of comorbidities, metabolic acidosis, steroid use, and ventilator duration were significant predictors of delirium severity (p < 0.05) and explained 24.4% of the variance. Hypoactive delirium was the most prevalent subtype (90.9%), but its subtle clinical presentation often led to underdiagnosis.

Conclusions: Advanced age, comorbidities, corticosteroid use, metabolic acidosis, and prolonged ventilator support were significant predictors of delirium severity in ICU patients. Although hypoactive delirium was not statistically linked to severity, its high prevalence (90.9%) underscores its relevance. These findings support cognitive assessments in ICUs for early detection and timely intervention. In resourcelimited environments, improving delirium recognition and management through focused nursing education and non-pharmacological strategies—such as environmental reorientation, sleep optimization, and individualized care — may enhance patient outcomes. Further multicenter studies are needed to validate these findings across diverse settings and develop tailored protocols for low-resource healthcare systems.