Increased Risk of Postoperative Complications in Elderly Hip Fracture Patients With Cognitive Impairment: Evidence From a Japanese Nationwide Database.

Abstract

Background: Hip fractures are a major cause of morbidity and mortality in the elderly. Cognitive impairment is known to be associated with poor postoperative outcomes, but its specific impact on complications following hip fracture surgery remains under-investigated in Japan.

Methods: This nationwide retrospective cohort study used the Diagnosis Procedure Combination (DPC) database to analyze patients aged ≥ 65 years who underwent surgical treatment for hip fractures between April 2016 and March 2022. Cognitive impairment was identified using ICD-10 codes. Propensity score matching (1:1) was performed using age, sex, body mass index, anesthesia type, fracture classification, surgical procedure, and Charlson Comorbidity Index. The primary outcomes were postoperative complications and in-hospital mortality; secondary outcomes included length of hospital stay and use of anti-osteoporotic medications.

Results: Of 474 293 eligible patients, 104 221 had cognitive impairment (22.0%). After matching, 96 982 patients were included in each group. Multivariate logistic regression showed that cognitive impairment was associated with higher risks of venous thromboembolism (odds ratio [OR]: 1.168, 95% confidence interval [CI]: 1.121-1.219), urinary tract infection (OR: 1.619, 95% CI: 1.543-1.699), and pneumonia (OR: 1.583, 95% CI: 1.510-1.661), all p < 0.0001. In-hospital mortality was similar between groups (2.0% vs. 1.9%). Patients with cognitive impairment had longer hospital stays (36.2 ± 29.9 vs. 34.6 ± 28.3 days) and lower rates of anti-osteoporotic medication use.

Conclusion: Cognitive impairment is an independent risk factor for postoperative complications in elderly hip fracture patients. Tailored perioperative strategies are needed to improve outcomes in this high-risk group.