Does self-efficacy mediate functional change in older adults participating in an exercise program after hip fracture? A randomized controlled trial

Objectives To examine whether self-efficacy mediated the effect of the Home-based Post-Hip Fracture Rehabilitation program on activity limitations in older adults after hip fracture and whether the mediating effect was different between sex and age groups. Design Randomized controlled trial. Setting Community. Participants Participants with hip fracture (N=232; mean age ± SD, 79±9.4y) were randomly assigned to intervention (n=120, 51.7%) and attention control (n=112, 48.3%) groups. Interventions The 6-month intervention, the Home-based Post-Hip Fracture Rehabilitation, is a functionally oriented, home-based exercise program. Data were collected at baseline, postintervention (6mo), and follow-up (9mo). Main Outcome Measures Activity Measure for Post-Acute Care. Results The mediating effect of the Home-based Post-Hip Fracture Rehabilitation program on Basic Mobility function through self-efficacy for exercise was significant at 9 months (β_indirect=.21). Similarly, the mediating effect of the intervention on Daily Activity function through self-efficacy for exercise was significant at 9 months (β_indirect=.49). In subgroup analyses, the mediating effect was significant at 9 months in the younger group (age, ≤79y) in comparison to the older group and was significant in women in comparison to men. Conclusions Self-efficacy may play a partial mediating role in the effect on some longer-term functional outcomes in the Home-based Post-Hip Fracture Rehabilitation intervention. The results suggest that program components that target self-efficacy should be incorporated in future hip fracture rehabilitation interventions. Age and sex of the targeted participants may also need to be considered when developing interventions.