Risk factors of delirium in elderly patients with hip fracture

Background: Delirium is a leading cause of death and disability in the elderly with hip fracture. Identifying reliable risk factors for delirium is critical to support optimal outcomes for prevention and reducing delirium. Objective: To quantify the reported factors associated to delirium for patients with hip fracture. Methods: Electronic databases were searched (including Medline, Pub Med, CINAHL, EMBASE, Evidence Based Medicine Reviews, Cochrane Review, Web of Science, and PsycINFO) to identify all studies, published in English language that evaluated the risk factors of delirium hospitalized people with hip fracture. Two reviewers independently assessed methodology quality and extracted relevant data. The data from the included studies were summarized, and pooled estimates were calculated for 12 risk factors. Results: Thirty-seven studies were included in the review and 25 in the meta-analysis. The incidence of delirium was 32.4% (95% confidence interval [CI] = 25.9%–39.5%). Six predisposing and four precipitating factors predicted delirium among older patients with hip fracture confirmed. The predisposing factors included advanced age (ES = 1.06, 95% CI = 1.03–1.09), male sex (ES = 1.34, 95% CI = 1.08–1.68), impairment of cognition (ES = 2.91, 95% CI = 1.91–4.42), and function (ES = 1.75, 95% CI = 1.39–2.2), comorbidity (ES = 1.59, 95% CI = 1.30–1.96), and health problems (ES = 2.64, 95% CI = 2.04–3.42). Precipitating factors were hypo- or hypernatremia (ES = 1.73, 95% CI = 1.14–2.64), depression (ES = 4.07, 95% CI = 1.95–8.49), more than three prescribed drugs (ES = 1.28, 95% CI = 1.10–1.49), and drugs including opioids (ES = 2.13, 95% CI = 1.42–3.18) and anticholinergic agents (ES = 2.10, 95% CI = 1.60–2.75). Conclusion: This meta-analysis result provides evidence that these risk factors have a significant impact on delirium in elders with hip fracture during hospitalization. Developing formal screening, and effective preventive and management strategies for delirium is important. Keywords: Delirium, elderly, hip fracture, risk factors, systematic review