Decreased glomerular filtration rate estimated by 2009 CKD-EPI equation predicts mortality in older hip fracture population.

Objective: We examined estimated glomerular filtration rate using the Chronic Kidney Disease Epidemiology equation (eGFRCDK-EPI), removal of urinary catheter during hospitalization and polypharmacy as predictors of mortality in older hip fracture patients.

Methods: Population-based prospective data were collected on 1425 consecutive hip fracture patients aged ≥65 years. Outcome was mortality at one year. Independent variables were age, sex, body mass index, fracture type, American Society of Anesthesiology score, delay to surgery, urinary catheter removal during acute hospitalization, eGFRCDK-EPI, number of daily medications, diagnosis of memory disorder, prefracture mobility and living arrangements.

Results: Of the 1425 patients, 567 (40%) had renal dysfunction on admission, 526 (37%) had their urinary catheters removed during hospitalization and 1177 (83%) were taking ≥4 medications regularly before the fracture. In the multivariate analyses with the Cox proportional hazards model adjusted simultaneously for all the independent variables, eGFRCDK-EPI 30-44ml/min/1.73m(2) (HR 1.91, 95% CI 1.44-2.52) and <30ml/min/1.73m(2) (HR 1.95, 95% CI 1.36-2.78), non-removal of the urinary catheter (HR 1.45, 95% CI 1.12-1.88) and large number of daily medications (4-10 HR 1.81, 95% CI 1.78-2.79, >10 HR 2.21, 95% CI 1.38-3.54) were associated with mortality.

Conclusions: In older hip fracture patients, moderate to severe level renal dysfunction measured by eGFRCDK-EPI, non-removal of urinary catheter before discharge and polypharmacy increase mortality after hip fracture. Careful assessment of renal function and medications and following the care protocols on urinary catheter removal are essential in the care of geriatric hip fracture patients.