Peer mentoring for physical activity adoption and maintenance among breast cancer survivors: moderators of physical activity outcomes

Purpose: We aimed to identify the moderators of maintenance strategies’ effects to assist cancer care organizations that offer peer mentoring physical activity programs. Methods: A total of 161 inactive breast cancer survivors participated in a 12-month study and were randomized to one of three conditions at baseline. American Cancer Society’s Reach to Recovery coaches delivered weekly calls to participants for the first 3 months. During Months 4–9, participants self-monitored PA and received feedback (Reach Plus) or additionally received monthly calls from coaches (Reach Plus Phone) or weekly text/email messages (Reach Plus Message). Moderate-to-vigorous PA (MVPA) was assessed using self-report and accelerometry at baseline, 3, 6, 9, and 12 months. We examined baseline demographics, cancer-specific, and social cognitive variables as potential moderators of MVPA. Using Latent Class Models, we identified three participant profiles. The profile was used as a moderator in longitudinal mixed-effects models of MVPA. Results: Profile 1 (44%) were married, White, in preparation, with higher income and higher social support. Profile 2 (41%) were older, office employees, African American, with higher PA self-efficacy. Profile 3 (15%) were diagnosed with stage 1 cancer, in contemplation, with higher MVPA and lower social support. At follow-ups, among those with Profile 1, Reach Plus participants had higher MVPA than other groups (f²≥.10). Among those with Profile 2, Reach Plus Message participants had higher mean MVPA than other groups (f²≥.11). Among those with Profile 3, Reach Plus Phone participants had higher MVPA than other groups, f²≥.11 (all ps <.05). Conclusions: Organizations can choose PA maintenance strategies that are most effective for survivors with specific profiles. Implications for Cancer Survivors: Breast cancer survivors with specific profiles increase PA when receiving certain PA maintenance programs. Trial Registration: ClinicalTrials.gov ID: NCT02694640 (Feb. 26, 2016).