Malnutrition, poor function and comorbidities predict mortality up to one year after hip fracture: a cohort study of 2800 patients

Purpose Despite extensive research, a complete understanding of factors influencing mortality risk after hip fractures is lacking. Previous research has focused on static risk factors; however, to improve outcomes, attention should be directed towards risk factors that may be optimised. The present study aimed to investigate the association of 19 risk factors with mortality among patients with hip fracture treated according to a well-defined guideline. Methods The study was a retrospective analysis of a large prospective patient cohort with all consecutive patients surgically treated for a hip fracture from January 2011 to December 2017 included (n = 2800). Variables were obtained from patient records and the Holstebro Hip Fracture Database comprising prospectively registered data on demographics, comorbidity, malnutrition (low Body Mass Index (BMI) or albumin) and hospital stay (including fracture and surgical data, biochemistry, mobilisation and discharge). Outcomes were 30-day and one-year mortality. Results Patients were predominantly female (66%); median age 81.6 years. Overall mortality was 9% at 30 days and 24% at one year. Age >= 75 years, male gender, nursing home residence, cognitive impairment, American Society of Anesthesiologists (ASA) score >= 3, BMI < 20 kg/m(2), albumin < 35 g/l, creatinine >= 100 mu mol/l, a low New Mobility Score and no mobilisation were all associated with increased mortality at 30 days and one year. Conclusion In addition to non-modifiable risk factors, comorbidities (expressed as high ASA score and creatinine), malnutrition, and failure to achieve early post-operative mobilisation were associated with increased short and long-term mortality among patients with hip fracture: these are potentially modifiable. The effect of optimisation interventions warrants further research. Key summary pointsAim To examine the association of 19 risk factors with mortality among patients with hip fracture treated according to a well-defined guideline focusing on risk factors that can be optimised. Findings Age, gender, residence, cognitive function, comorbidities, nutritional status, functional level and mobilisation were all associated with mortality at 30 days and one year. Message The present study supports the efforts of orthogeriatric care in optimising risk factors such as comorbidities, malnutrition and in-hospital rehabilitation. Future studies exploring how and when optimisation should be implemented are warranted.