Predictors of mobility status one year post hip fracture among community‐dwelling older adults prior to fracture: A prospective cohort study

Abstract

AbstractBackgroundOrthopedists and other clinicians assess recovery potential of hip fracture patients at 2 months post‐fracture for care planning. It is unclear if examining physical performance (e.g., balance, gait speed, chair stand) during this follow‐up visit can identify individuals at a risk of poor functional recovery, especially mobility, beyond available information from medical records and self‐report.MethodsData came from 162 patients with hip fracture enrolled in the Baltimore Hip Studies‐7th cohort. Predictors of mobility status (ability to walk 1 block at 12 months post‐fracture) were the Short Physical Performance Battery (SPPB) comprising balance, walking and chair rise tasks at 2 months; baseline medical chart information (sex, age, American Society of Anesthesiologist physical status rating, type of fracture and surgery, and comorbidities); and self‐reported information about the physical function (ability to walk 10 feet and 1 block at pre‐fracture and at 2 months post‐fracture). Prediction models of 12‐month mobility status were built using two methods: (1) logistic regression with least absolute shrinkage and selection operator (LASSO) regularization, and (2) classification and regression trees (CART). Area under ROC curves (AUROC) assessed discrimination.ResultsThe participants had a median age of 82 years, and 49.3% (n = 80) were men. Two‐month SPPB and gait speed were selected as predictors of 12‐month mobility by both methods. Compared with an analytic model with medical chart and self‐reported information, the model that additionally included physical performance measures had significantly better discrimination for 12‐month mobility (AUROC 0.82 vs. 0.88, p = 0.004).ConclusionAssessing SPPB and gait speed at 2 months after a hip fracture in addition to information from medical records and self‐report significantly improves prediction of 12‐month mobility. This finding has important implications in providing tailored clinical care to patients at a greater risk of being functionally dependent who would not otherwise be identified using regularly measured clinical markers.