Evaluating the relationship between inflammatory markers and preoperative delirium in elderly hip fracture patients: A retrospective observational study

Preoperative delirium is common and associated with poor clinical outcomes in elderly hip fracture patients. Although inflammatory markers have shown potential in predicting postoperative delirium, their relevance to preoperative delirium remains unclear. This study aimed to investigate the relationship between inflammatory markers and preoperative delirium to improve risk prediction and management strategies. We retrospectively studied 548 elderly hip fracture patients aged 70 years or older. The primary outcome was preoperative delirium diagnosed using the Confusion Assessment Method (CAM). Explanatory variables included inflammatory markers (neutrophil-to-lymphocyte ratio [NLR], platelet-to-lymphocyte ratio [PLR], systemic immune-inflammation index [SII], inflammatory burden index [IBI], and systemic inflammation response index [SIRI]). About 7.66% of patients developed preoperative delirium in the study. These patients were more likely to be older, have comorbid cardiovascular disease, and be transferred to an internal medicine ward for further treatment (P < .001). Multivariate analysis further revealed that older age (OR = 1.11, 95% CI = 1.04-1.18) and comorbid cardiovascular disease (OR = 2.94, 95% CI = 1.51-5.67) were independently associated with the occurrence of preoperative delirium. No significant differences were observed between groups for inflammatory markers: NLR (P = .70), PLR (P = .09), IBI (P = .09), SII (P = .21), or SIRI (P = .80). Older age and cardiovascular comorbidities were independent risk factors for preoperative delirium. No significant associations were found with inflammatory markers. Future research should explore additional biomarkers to refine risk stratification in this population.