[2026-11-04] Occurrence and Associated Factors of Delirium in Elderly Orthopedic Patients: A Prospective Observational Study

Background: Delirium is a common neuropsychiatric disorder in elderly patients, characterized by an acute decline in cognitive function. It is associated with increased complications and mortality. Identifying factors associated with its occurrence is crucial for guiding clinical management. Objectives: To determine the incidence of delirium during hospitalization in the orthopedic department and identify unadjusted factors associated with the occurrence of delirium in elderly patients. Methods: Patients aged 60 years or older admitted to the orthopedic department, HRH Princess Maha Chakri Sirindhorn Medical Center between August 2024 and February 2025 were included. Data were collected using structured forms and categorized into delirium and nondelirium groups based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition criteria. Statistical analyses included chi-square test, Fisher exact test for categorical variables, and independent t test for continuous variables. A P value < .05 was considered statistically significant. Results: A total of 150 patients were enrolled, of whom 13 developed delirium, resulting in cumulative incidence of 8.67%. Unadjusted factors significantly associated with delirium included advanced age (P < .001), particularly in patients aged over 80 (P < .001), and electrolyte imbalances, specifically hyponatremia (P = .003) and hypokalemia (P = .020). Conclusions: Delirium occurs in a notable proportion of elderly orthopedic patients, showing unadjusted associations with advanced age and electrolyte imbalances. Due to the lack of multivariable adjustment, these findings should be interpreted cautiously to guide early clinical screening and vigilant monitoring.