Optimizing recovery after a hip fracture: Protocol of a randomized controlled trial to study the effects, costs, and cost-effectiveness of a combined protein and exercise intervention in older adults after a hip fracture (ProBUS study).

BACKGROUND

Hip fractures are common among older adults and typically occur alongside accumulating comorbidities and age-related musculoskeletal decline. While nutritional or exercise interventions can support recovery, the effect of a combined approach during rehabilitation remains unclear. This study aims to evaluate the effects, costs, and cost-effectiveness of a high-protein diet plus exercise intervention on functional recovery after a hip fracture.

METHODS

This randomized controlled trial will include 102 older adults (≥65 years) recovering in a rehabilitation centre after a hip fracture. Participants will be randomly assigned (1:1) to the intervention or control group, stratified by sex and hospital. The intervention group will receive weekly dietitian support to comply with a high-protein diet (≥1.2 g/kg body weight/day) and will participate in progressive resistance exercise training twice weekly for 3 months. The control group will receive usual care. Due to the nature of the intervention, participant and staff blinding is not feasible, but analyses will be performed blinded. Measurements will be performed in the first week after surgery, at rehabilitation discharge, and 3 months after baseline. The primary outcome is physical functioning using the Short Physical Performance Battery. Secondary outcomes include handgrip strength, muscle mass, bone density, quality of life, daily functioning, nutritional status, bone metabolism biomarkers, and costs.

DISCUSSION: The intervention is expected to enhance recovery, attenuate postoperative bone and muscle loss, and improve quality of life. Implementation into standard care could improve efficiency and cost-effectiveness.