Abstract P6-11-02: Reduced sedentary time intervention for breast cancer survivors: objectively-measured outcomes for activity and metabolism
Authors: Walker RK , Viskochil R , Barham R , Moraitis A , Gagliarducci J , Makari-Judson G 
Published: May 2019

Abstract
Physical activity (PA) promotion and sedentary behavior reduction among cancer survivors is a national priority and the number of PA-based behavioral interventions has expanded considerably in recent years. However, due in part to past limitations related to precise quantitative measurement of sedentary behaviors, there have been relatively few trials focused on reduction of sedentary time among cancer survivors. Additionally, many PA interventions rely on clinic-based coaching, which is both time-intensive and unrealistic for many clinics. The purpose of this study was to investigate the effects of a home-based 6-week reduced sedentary time intervention (RSTI) in breast cancer survivors who had completed primary treatment. Questionnaires, anthropometric measures, fasting blood glucose, lipid profiles and other cancer-relevant biomarkers, and an oral glucose tolerance test to assess dynamic insulin were completed at baseline and post-intervention. Participants wore ActivPALs (on right thigh) for 7 days at baseline and post-intervention. The mailed RSTI included tailored feedback on PA and sedentary habits and provision of personalized visual displays generated from baseline ActivPal data, with specific tips for how to reduce sedentarism through environmental modifications to home and work spaces (example: moving your printer from next to your desk to down the hall). Eligibility criteria included: females ages 20-80; not meeting national exercise guidelines (150 minutes per week); diagnosis of Stage I-III breast cancer treated &gt;6 months and &lt;5 years prior; overweight or obese (BMI &gt;25); no history of diabetes. Sixteen enrolled and 13 completed the study. Average BMI at baseline was 31.9 and all participants' daily step counts were significantly below national recommendations (mean=6190 steps/d, SD: 2086 steps/d). Post-intervention changes from baseline were analyzed using non-parametric statistics. No statistically significant changes in daily bouts of sedentarism, energy expenditure, or total steps were detected, although participants' mean daily steps post-intervention were 6326/d (SD: 2788/d), still well below recommended guidelines. Leptin levels also showed a significant reduction pre/post (p&lt;0.01). Results indicate that similar home-based RSTIs are safe, acceptable to survivors, and feasible to implement by cancer center staff. Further research with larger samples is required to establish efficacy and effect sizes for the intervention. A larger intervention dose may be required to see clinically-meaningful changes in sedentarism, daily activity, and metabolism.
Citation Format: Walker RK, Viskochil R, Barham R, Moraitis A, Gagliarducci J, Makari-Judson G. Reduced sedentary time intervention for breast cancer survivors: objectively-measured outcomes for activity and metabolism [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-11-02.