JMIR Publications

ABSTRACT

Background:

Breast cancer is the most diagnosed cancer among women and is the leading cause of cancer death among Latinas. Breast cancer survivors are at increased risk for adverse health impacts, such as unwanted weight gain and obesity, which can be exacerbated by and contribute to symptom burden. Other important influencers of body mass index (BMI) include social interactions with others.

Objective:

We examined the association between different social network interactions and change in BMI among Latina and non-Hispanic white (NHW) breast cancer survivors engaging in a mobile-health application pilot study.

Methods:

Latina and NHW breast cancer survivors were randomized to engage in either Mi Salud or Mi Vida, Mi Salud. Mi Salud allowed participants to engage in self-monitoring by recording their behaviors and symptoms. Mi Vida, Mi Salud employed these same features in addition to a self-discovery feature which would summarize and report back this information to participants. We collected information on BMI and social interactions (social support, pressure, persuasion, and undermining) at baseline and after 12 weeks of the intervention.

Results:

Participants in Mi Salud and in Mi Vida, Mi Salud did not differ in change of BMI over the 12 weeks. Increased social support was associated with decreased BMI at the trend-level (B=-0.23, p=0.05). Change in persuasion was not associated with change in BMI (B=0.06, p=0.70). However, increased pressure was associated with increased BMI (B=0.66, p=0.02). Lastly, increased undermining was associated with increased BMI at the trend-level (B=0.35, p=0.08). The interaction between change in social support and ethnicity resulted in improved model fit. Predicted margins were significant at the trend-level for NHW, but not for Latinas (B=-0.4, p=0.07 and B=-0.3, p=0.2, respectively).

Conclusions:

There exist relatively few mobile-health applications that allow for both self-discovery and self-monitoring. The null findings associated with our assessment of the relationship between application group and change in BMI made be indicative of the relatively little difference between the two groups. That is, it may be that the self-monitoring component of the application was sufficient for both groups to identify and reflect on their behaviors. Our findings regarding social engagement and change in BMI show the importance of considering social interactions in the management of symptoms and weight loss among breast cancer survivors. Specifically, for both Latina and NHW women, negative social control (pressure) was associated with increased BMI. For NHW women in particular, increased social support appeared to be important for weight loss.