Acute Kidney Injury in Patients Undergoing Hip Fracture Surgery.

BACKGROUND

Hip fracture is common in elderly patients and is associated with high morbidity and mortality. Acute kidney injury (AKI) following hip fracture may have additional impact on clinical outcomes.

OBJECTIVES

To investigate the incidence of AKI, the risk factors for its occurrence and impact on mortality, timing of surgery, and length of hospitalization (LOS) in patients undergoing hip fracture surgery.

METHODS

We retrospectively examined the records of patients who underwent hip fracture surgery between 2013 and 2017. All patients had a baseline serum creatinine value and at least one later value. AKI was defined according to KDIGO guidelines.

RESULTS

The study included 511 patients. Mean age was 72.6 years, 325 males (63.4%); 151 (29.5%) had baseline eGFR < 60 ml/min/1.73m2. Of these, 87 (17%) developed AKI. Older age, diabetes mellitus, hypertension, and chronic heart condition were significantly more common in patients who developed AKI. Patients with AKI had increased 30-day mortality (hazard ratio [HR] 3.96, 95% confidence interval [95%CI] 1.62-9.7, P = 0.003) and mortality at one year (HR 2.72, 95%CI 1.5-4.9, P = 0.002). AKI was associated with surgery delay > 48 hours (HR 2.241, 95%CI 1.206-4.165, P = 0.011). Mean LOS was 10.9 days and 8 days for patients with AKI and without, respectively, P < 0.0001.

CONCLUSIONS

AKI is a common complication in patients with hip fracture and is associated with increased short- and long-term mortality, delayed surgery, and longer hospitalization. Interventions identifying and monitoring patients at risk may contribute to improve the outcomes.