ANALYSIS OF RISK FACTORS FOR PREOPERATIVE DELIRIUM FOLLOWING GERIATRIC HIP FRACTURE AND ITS RELATIONSHIP WITH MORTALITY: A RETROSPECTIVE COHORT STUDY

ABSTRACT Introduction: Although postoperative delirium in patients with hip fractures has been extensively studied, preoperative delirium has rarely been examined. We investigated the risk factors for developing preoperative delirium in patients with hip fracture and their relation to mortality. Materials and Method: We retrospectively reviewed the records of 316 patients who underwent hip fracture surgery. Preoperative delirium was defined according to the Diagnostic and Statistical Manual-5 criteria, and the time of onset of delirium (0-24 hours) was recorded. We evaluated patient demographics, medical conditions, laboratory results, movement patterns, and death rates. Results: Preoperative delirium occurred in 16.5% of the patients. Most patients who experienced delirium developed symptoms during the first six hours of hospitalization. The preoperative delirium group showed lower serum albumin levels (3.2±0.5 vs 3.6±0.6 g/dL, p<0.001), lower prognostic nutritional index values (31.2±6.8 vs 36.1±7.5, p<0.001) and elevated creatine kinase levels (168 vs 92 U/L, p<0.001). Alzheimer’s/dementia (odds ratio: 5.43), creatine kinase levels above 100 U/L (odds ratio: 3.65), albumin levels below 3.5 g/dL (odds ratio: 3.12), prognostic nutritional index values under 35 (odds ratio: 2.78) and dependent mobilization (odds ratio: 2.18) were independent risk factors. The multivariate logistic regression model showed suitable discrimination power through its area under curve value of 0.687 which fell within a 95% confidence interval of 0.599 to 0.774 while achieving sensitivity at 65.8% and specificity at 61.2% and accuracy at 61.7%. The preoperative delirium group experienced a 36.5% one-year mortality rate, which was significantly higher than the 18.2% mortality rate in the non-delirium group (p=0.001). Conclusion: The risk factors for preoperative delirium include low albumin levels, low prognostic nutritional index values, elevated creatine kinase, dependent mobilization, and neurocognitive impairment. The presence of preoperative delirium leads to an extended postoperative delirium duration and elevated patient mortality rates. The research results require analysis based on the study design which used a single center to collect retrospective data and the difficulties of detecting delirium through medical records analysis. Keywords: Delirium; Hip Fractures; Mortality; Creatine Kinase; Nutrition Assessment.