Motivational interviewing intervention for increasing physical activity and improving dietary behaviors: The Lupus Intervention Fatigue Trial protocol.

The Lupus Intervention Fatigue Trial (LIFT) is a prospective, randomized controlled trial to assess the effectiveness of a six-month motivational interviewing intervention program versus an educational control to reduce fatigue in persons with systematic lupus erythematosus (SLE). Participants are randomized using a stratified, 1:1 allocation design to the LIFT intervention or control arm. We plan to enroll 236 participants to achieve the target of 200 persons with six-month follow-up for the primary endpoint. Specific aims of this study are to evaluate the impact of the LIFT intervention on 1) self-reported measures of fatigue and 2) impact on accelerometer-measured physical activity. The primary study outcome is six-month change in fatigue from baseline, assessed by the Fatigue Severity Score (FSS). Additional outcomes include objective measures of physical activity, including non-sedentary behavior and moderate-to-vigorous activity (secondary outcome), and adherence to the LIFT dietary intervention, as assessed by nutrient density (diet quality) and recommended food groups/eating patterns (exploratory outcome) in persons with SLE. Intervention effectiveness will be assessed using an intention-to-treat two-arm comparison of six-month change in FSS, with one interim monitoring analysis. A two-sample independent group t-test will compare the six-month changes in FSS between the study arms. Intervention effect durability will be assessed 12-months after baseline (6 months after completion of the intervention). Enrollment began in June 2019 and is expected to end in June 2023. This study will inform future intervention strategies that promote physical activity and improved diet quality to reduce fatigue in persons with SLE.