Prehabilitation of elderly frail or pre-frail patients prior to elective surgery (PRAEP-GO): study protocol for a randomized, controlled, outcome assessor-blinded trial
Authors: Schaller Stefan J. , Kiselev Jörn , Loidl Verena , Quentin Wilm , Schmidt Katrin , Mörgeli Rudolf , Rombey Tanja , Busse Reinhard , Mansmann Ulrich , Spies Claudia ,   on behalf of the PRAEP-GO consortium,, Spies Claudia , Marschall Ursula , Eckardt-Felmberg Rahel , Landgraf Irmgard , Schwantes Ulrich , Busse Reinhard , Mansmann Ulrich ,   PRAEP-GO investigators, Borchers Friedrich , Mörgeli Rudolf , Schönenberger Eva , Klassen Philipp , Kleikamp Bernadette , Brandhorst Philipp , Spiegel Anna-Lena H. , Papenfuß Bernhard , Dowideit Jens , Oefele Caroline , Gebhardt Volker , Zappel Kristina , Gövercin Mehmet , König Thomas , Chesi Claudio , Reißhauer Anett , Rosada Adrian , Müller-Werdan Ursula , Heymann Anja , Hanke Marion , Leymann Jens , Saller Thomas , Bischof Ann-Cathrin , Reisner Angelika , Albrecht Wolf Leopold , Wojciechowski Julia , Schuldt Martina , Baum Michael , Brnabic Dijana , von Pickardt Björn , Deutschmann Agnieszka , Scholz Carsten , May Lars , Eckardt-Felmberg Rahel , Wenghöfer Isabell , Blobner Manfred , Sattari Sima , Dummert Michael , Nau Carla , Otto Mareike , Voß-Lümers Ute , Lang Danny , Wiggert Daniel 
Published: June 2022

Abstract
Background
Frailty is expressed by a reduction in physical capacity, mobility, muscle strength, and endurance. (Pre-)frailty is present in up to 42% of the older surgical population, with an increased risk for peri- and postoperative complications. Consequently, these patients often suffer from a delayed or limited recovery, loss of autonomy and quality of life, and a decrease in functional and cognitive capacities. Since frailty is modifiable, prehabilitation may improve the physiological reserves of patients and reduce the care dependency 12 months after surgery.

Methods
Patients ≥ 70 years old scheduled for elective surgery or intervention will be recruited in this multicenter, randomized controlled study, with a target of 1400 participants with an allocation ratio of 1:1. The intervention consists of (1) a shared decision-making process with the patient, relatives, and an interdisciplinary and interprofessional team and (2) a 3-week multimodal, individualized prehabilitation program including exercise therapy, nutritional intervention, mobility or balance training, and psychosocial interventions and medical assessment. The frequency of the supervised prehabilitation is 5 times/week for 3 weeks. The primary endpoint is defined as the level of care dependency 12 months after surgery or intervention.

Discussion
Prehabilitation has been proven to be effective for different populations, including colorectal, transplant, and cardiac surgery patients. In contrast, evidence for prehabilitation in older, frail patients has not been clearly established. To the best of our knowledge, this is currently the largest prehabilitation study on older people with frailty undergoing general elective surgery.

Trial registration
ClinicalTrials.gov NCT04418271. Registered on 5 June 2020. Universal Trial Number (UTN): U1111-1253-4820