Background Breast cancer is the most commonly diagnosed cancer among women and is the leading cause of cancer death among Latina individuals. Breast cancer survivors are at increased risk of obesity. Mobile health interventions have been shown to be an effective way of reducing the risk of weight gain. Less studied but also important is the extent to which social networks play a role in supporting or undermining weight loss efforts. Objective We examined the association between 4 kinds of social network interactions and change in BMI among Latina and non-Hispanic White breast cancer survivors engaging in a mobile health app pilot study. Methods Latina and non-Hispanic White breast cancer survivors were randomized to engage in either the Mi Salud or Mi Vida, Mi Salud app. Mi Salud allowed participants to engage in self-monitoring by recording their behaviors and symptoms. Mi Vida, Mi Salud used these same features in addition to a self-discovery feature that would summarize and report back this information to participants. We collected information on BMI and health-related social support; positive and negative health-related social control (which included persuasion and pressure, respectively); and undermining at baseline and after 12 weeks of the intervention. Results While participants (non-Hispanic White n=22 and Latina n=22) in both study arms experienced decreased BMI over the 12-week period, this change in BMI did not differ according to ethnicity. Furthermore, change in social support was not associated with decreased BMI (B=−0.19, P=.12). However, the interaction between change in social support and ethnicity was significant, such that predicted margins were significant for non-Hispanic White individuals (B=−0.57, P=.02) but not for Latina individuals (B=−0.54, P=.72). Change in persuasion was not associated with change in BMI (B=0.072, P=.61); however, increased pressure was associated with increased BMI (B=0.66, P=.02). Finally, change in undermining was not associated with change in BMI (B=0.32, P=.11). Conclusions Latina and non-Hispanic White participants did not differ in weight loss. However, our findings regarding social network involvement and change in BMI show the importance of considering social network processes in weight loss among breast cancer survivors. These findings buttress existing research suggesting the benefits of social support, particularly within specific cultural frameworks, while attempts to increase participants’ healthy behaviors that involve criticism can be detrimental to change efforts. Future research that builds on these findings is needed to elucidate the specific social network processes that may drive health behavior among diverse breast cancer survivors.
Janio et al. (Thu,) studied this question.