Twelve month mortality rates and independent living in people aged 65 years or older after isolated hip fracture: A prospective registry-based study

•Hip fracture in older adults (65 years or older) results in high burden 12 months post-injury: 28% died, 46% had substantial disability.•Social disadvantage, frailty and poor pre-injury health and independence increased mortality rates and reduced independence.•The potential to address modifiable factors associated with poor outcomes should be examined. Introduction: This study investigated which patient and injury characteristics are associated with 12-month mortality rates and living independently after isolated hip fracture. Methods: Older adults aged ≥65 years were included if they had an isolated hip fracture, were admitted to hospital between July 2009 and June 2016, inclusive, and were registered to the Victorian Orthopaedic Trauma Outcomes Registry. Mortality up to 12 months (365 days) post-injury, and functional outcomes (Glasgow Outcome Scale-Extended; GOS-E) at 12 months post-injury were examined. Multivariable Cox proportional hazards regression was used to estimate adjusted hazard ratios (aHRs), and multivariable logistic regression was used to identify predictors of living independently compared with severe disability or death on the GOS-E. Results: 4,912 patients were included, of whom 28% died, 46% had moderate-severe disability, and 26% were living independently 12 months post-injury. Mortality rates were lower in women (aHR=0.56, 95%CI: 0.50, 0.63), and in people injured in a high fall vs low fall (aHR=0.47, 95%CI: 0.31, 0.72). Mortality rates were higher in people in the older age groups (75–84 years: aHR=1.53, 95%CI: 1.21, 1.93; 95+ years: aHR=3.58, 95%CI: 2.68, 4.77), living in areas with the highest level of socioeconomic disadvantage (aHR=1.25, 95%CI: 1.01, 1.55), with a Charlson Comorbidity Index weighting of one (aHR=1.60, 95%CI: 1.36, 1.88) or more than one (aHR=2.21, 95%CI: 1.94, 2.53), whose injury occurred in a residential institution versus at home (aHR=2.63, 95%CI: 1.97, 3.52), that resulted in intensive care unit admission (aHR=1.68, 95%CI: 1.21, 2.32), and in people who did not have surgery versus people who had internal fixation (aHR=1.65, 95%CI: 1.33, 2.04). Independent living was inversely associated with most of the same characteristics; however, people also had lower odds of living independently if they were from metropolitan residential areas versus rural areas (aOR=0.77, 95%CI: 0.62, 0.96), or had mild to moderate (aOR=0.33, 95%CI: 0.27, 0.39) or marked to severe (aOR=0.13, 95%CI: 0.09, 0.20) preinjury disability vs