Evaluation of a clinically integrated mHealth intervention to reduce sedentary time in adolescents and young adults with ALL during maintenance therapy

Background: Sedentary behavior (SB) is prevalent in early adolescents and young adults (eAYAs, 12-21 years) during acute lymphoblastic leukemia (ALL) treatment and contributes to cardiometabolic complications. Intervention during therapy can be challenging, but the maintenance phase may be opportune for SB intervention as toxicity from intensive therapy subsides and monthly visits allow for regular study contact. Purpose: To evaluate the feasibility and acceptability of a clinically integrated, multi-component mobile health (mHealth) SB intervention in eAYAs during ALL maintenance phase; and assess effects on SB and health-related quality of life (HRQoL). Methods: This ongoing 12-week, single-arm pilot trial includes a Fitbit with inactivity-triggered prompts, three in-clinic or virtual coaching sessions, and an app-based peer chat group. The intervention is aligned with one 12-week cycle of maintenance therapy, and in-person procedures coincide with monthly clinic visits. Feasibility is defined as ≥70% retention, N=20 enrolled, and Fitbit wear time ≥10 h/day on ≥70% days for ≥50% of sample. Acceptability is evaluated via exit surveys. At baseline and week 12, SB is assessed using the activPAL micro4 device and IPAQ questionnaire, and HRQoL is assessed via validated surveys. Outcome differences were compared by number of maintenance cycles completed at enrollment (≤ 2 [early] vs > 2 [late]). Results: To date, N=20 are enrolled and N=16 have completed the study (median age=16.2 yrs; 69% male; 69% Hispanic; median BMI=23.3kg/m 2 ; 56% in early maintenance). Retention among completers is 94% (N=15) and 38% (N=6) met Fitbit wear time criteria, the majority of whom were in early maintenance (83% [N = 5] vs 14% [N = 1] in late maintenance). Acceptability is high: 93% (N=14) reported the intervention helped reduce SB and 100% would recommend it to peers. A greater proportion of participants in early vs late maintenance strongly agreed the intervention reduced SB (helpful: 88% vs 29%, p = 0.05; recommend: 88% vs 0%; p = 0.001). Overall, device-measured sedentary and sitting time decreased (−10.4 min/day and −26.3 min/day, respectively) and steps increased (+1,993/day) (all p>0.05); self-reported sitting time also decreased (−154 min/day, p=0.002). Participants in early maintenance showed similar trends to those in later cycles. There were no significant changes in HRQoL. Conclusions: Preliminary findings indicate this mHealth SB intervention is feasible, acceptable, and can be clinically integrated during active maintenance therapy for eAYAs with ALL. Participants in early maintenance showed high adherence and engagement, suggesting the feasibility and benefit of SB intervention during active treatment for ALL and potential scalability to other types of cancer.