Efficacy of Tailored Messages for 28-Week Exercise Sustainability in People with HIV.

People with HIV (PWH) are at increased risk for cardiovascular diseases and other age-related comorbidities. These risks can be reduced through moderate to vigorous physical activity (MVPA), but MVPA can be difficult to sustain over time. We tested tailored text messages combined with motivational interviewing (MI) to sustain MVPA among PWH. Messages were created using Two Minds Theory and matched to daily survey responses about exercise barriers. 118 PWH ages ≥ 50 were initially randomized to high-intensity interval training or continuous moderate-intensity exercise. After 16 weeks, 92 participants were re-randomized to receive either tailored messages plus MI, or educational control messages, for 12 weeks. Both groups completed daily barrier surveys and wore an ActiGraph monitor for 1 week/month. PWH in the tailored-messaging plus MI group maintained their MVPA, ending at M = 30.5 min per day (SD = 36.7), compared to a decrease among PWH in the educational-control group, ending at M = 26.0 (SD = 25.8), F(1, 255) = 5.76, p = .02, d = 0.51 for the group-by-time interaction using intent-to-treat principles. Findings were similar based on both actigraphy and self-reported MVPA, and were robust to attrition. PWH in the tailored-messaging group also reported higher exercise self-efficacy and better perceived health over time, relative to the educational-control group. Exploratory analyses suggested that the tailored messages' effects were additive to motivational interviewing. In this study, an automated tailored-messaging intervention led to sustained MVPA. Tailored messages were superior to non-tailored educational messages, and may help PWH maintain their long-term health.Trial registry ClinicalTrials.gov study NCT04550676.