Elderly men with renal dysfunction are most at risk for poor outcome after neck of femur fractures.

BACKGROUND: both acute and chronic renal dysfunction (ARD and CRD) have been reported to influence outcomes after neck of femur fractures. We have examined the relationship between the length of stay, mortality and renal dysfunction using biomarkers. These included pre-operative (admission) serum concentrations of urea, creatinine and albumin, and estimated glomerular filtration rates (eGFR) derived from four- and six-variable Modification of Diet in Renal Disease (MDRD) study equations. METHODS: complete outcomes data for 566 patients and the patterns of variations in the biomarkers were analysed using generalised linear models. Cox-proportional hazard analyses investigated the association between kidney function (as assessed by the above-mentioned biochemical data) and post-operative length of stay and mortality. All patients were stratified for CRD according to their eGFR. RESULTS: serum urea and creatinine were significantly, positively correlated with age. After adjusting for age and sex, risk of mortality was positively related to six-variable eGFR and creatinine, and marginally so for urea. One-year mortality risk thus worsened with stages of CRD (1-4), increasing age and male gender. Risk of discharge from trauma ward, the length of stay in trauma ward and the overall length of stay were not related to urea and creatinine, but were negatively related to both four- and six-variable eGFR. CONCLUSIONS: the study has identified elderly renal-impaired males as the subgroup of patients most at risk for poor survival. This subgroup may require a more targeted approach to the management of their fluid and electrolyte homoeostasis to help improve their outcomes.