Nutritional Status Changes and Activities of Daily Living after Hip Fracture in Convalescent Rehabilitation Units: A Retrospective Observational Cohort Study from the Japan Rehabilitation Nutrition Database.

BACKGROUND: Several studies have suggested that malnutrition impedes functional recovery in patients with hip fracture, but there are few reports on improvement in nutritional status and return to activities of daily living (ADL) in these patients.

OBJECTIVE: This study was conducted to evaluate the relationship between change in nutritional status and recovery of ADL in malnourished patients after hip fracture and to identify predictors of functional recovery among the characteristic features of undernutrition.

DESIGN: This was a retrospective observational cohort study.

PARTICIPANTS/SETTING: Data for patients aged ≥65 years with hip fracture and malnutrition (Mini Nutritional Assessment-Short Form [MNA-SF] score ≤7) at the time of admission to convalescent rehabilitation units were obtained from the Japan Rehabilitation Nutrition Database between November 2015 and August 2017.

MAIN OUTCOME MEASURES: The main outcome measures were Functional Independence Measure (FIM) at discharge and the proportion of patients discharged home.

STATISTICAL ANALYSES PERFORMED: Patients were divided into two groups based on MNA-SF scores at discharge: improvement in nutritional status (>7, IN group) and non-improvement in nutritional status (≤7, NN group). Clinical characteristics and outcomes were compared between the groups. Multivariable regression analysis was performed to adjust for confounders including age, sex, comorbidity, pre-fracture ADL level, and FIM score on admission.

RESULTS: Of 876 patients, 110 met the eligibility criteria (mean age, 85 years; 78.2% female); 77 of the patients were assigned to the IN group and 33 to the NN group. The patients in the IN group were younger and had higher FIM and MNA-SF scores on admission than those in the NN group. At discharge, the median FIM score was significantly higher in the IN group than in the NN group (110 vs 83, P<0.001). Multivariable analysis revealed a significant association between improvement in nutritional status and higher FIM score at discharge (B=7.377 [B=partial regression coefficient], P=0.036) but no association with discharge to home. Mobility, neuropsychological impairment, and weight loss subscores of MNA-SF were independently associated with discharge FIM score (R2 =0.659).

CONCLUSIONS: In older patients with hip fracture and malnutrition, improvement in nutritional status was independently associated with improved performance of ADL during inpatient rehabilitation. Weight loss may be an important nutritional indicator for these patients.