Psychosocial Factors Predicting Physical Activity in Cancer Survivors

1. Psychosocial Factors Predicting Physical Activity in Cancer Survivors Matthew Cox, Ph.D. Postdoctoral Fellow Center for Energy Balance in Cancer Prevention and Survivorship

2. Benefit of physical activity (PA) for cancer prevention/survivorship • Decreased all-cause mortality risk • Decreased risk of cardiovascular disease and type II diabetes • 25% reduction in breast cancer risk • Decreased risk of kidney, lung, endometrial, colon, and prostate cancer • During cancer therapy • Improved physical functioning • Decreased fatigue • Decreased anxiety • Decreased sleep disturbances • Posttreatment • Improved fitness levels • Decreased body fat • Decreased waist circumference • Benefits moderated by type, frequency, intensity, and duration

3. Review of efficacy and safety for exercise in cancer survivors ACSM Roundtable on Exercise Guidelines for Cancer Survivors, 2010

4. Current PA Recommendations • ACSM Recommendations for healthy 18-65 yrs: • 30 minutes, five days a week of moderate-intensity aerobic physical activity OR 20 minutes three days a week of vigorous-intensity aerobic activity. • Can benefit from incorporating resistance training for all large muscle groups at least twice a week • Moderate-intensity = noticeably elevated hear rate (e.g., brisk walk) • Vigorous-intensity = substantially increased heart rate (e.g., jogging) • ACSM Recommendations for cancer: • The same as healthy adults for breast, prostate, colon, hematologic, and gynecologic cancers survivors without cancer site-specific contraindications

5. Lack of PA and Cancer Risk

6. Current Levels of PA in cancer survivors • Breast Cancer Survivors (Irwin, McTiernan, Bernstein, Gilliland, Baumgartner, R., Baumgartner, K., & Ballard-Barbash, 2004) • 32% of Breast cancer survivors meet current recommended levels • Obese breast cancer survivors less likely to meet recommendations than others • PA levels tend to decline after diagnosis (Blanchard et al., 2003) • Doesn’t return to prediagnosis levels • HOW DO WE GET PEOPLE TO EXERCISE?

7. Social Cognitive Theory (SCT; Bandura, 1977)

8. SCT (Bandura, 1997)

9. Social Cognitive Theory (SCT) and PA • Components of SCT (Bandura, 1997) • Social Support • Self-efficacy • One’s belief in one’s ability to engage in a targeted behavior • Outcome Expectancy • A person’s perception of whether a behavior is worth performing and whether the experience will be positive or negative. • Self-regulation • Self-monitoring • Self-regulation self-efficacy • Affective self-reaction

10. SCT and PA in sedentary people • SCT has been recommended by the Surgeon General as one of the guiding theories for PA (USDHHS, 1996) • Interventions using SCT have had some success in getting healthy/sedentary individuals to exercise • Review articles indicate that self-efficacy may be the mediating variable (Marcus et al., 2002) • Recent studies suggest that self-regulation is the more proximal mediator (Anderson et al., 2010)

11. SCT and PA in cancer survivors • Only just being applied in the last decade • Self-efficacy shown to predict changes in PA among cancer survivors • Inconsistent evidence regarding outcome expectancies

12. Rodgers et al., 2005 • Objective: • Determine the relationship between SCT constructs and PA in breast cancer patients receiving treatment • Sample: • 21 female patients • Stage I or II breast cancer • 90% white • Currently undergoing adjuvant therapy (i.e., chemo, radiation, or hormonal therapy)

13. Methods • Recruited from oncology clinics • Measured • PA via self-report 7 PA recall • PA via pedometer • Expectations and values Outcome expectancy • Positive/Negative Values • Positive/Negative Expectations • Barriers self-efficacy Self-regulation • Task self-efficacy Self-efficacy • Environment Self-regulation/Social support • Behavioral Capability Self-efficacy • Self-control and performance Self-regulation • Observational learning Self-efficacy • Reinforcement Self-regulation • Emotional Coping Self-regulation

14. Analyses • Converted self-reported PA into daily energy expenditure • Ran correlations for survey scores on both pedometer counts (avg daily steps) AND energy expenditure • Average number of steps was 5,525 per day • Average step count for U.S. individuals = 5,117 • Recommended number of step is 10,000 per day • Average energy expenditure was 10.3 kcal/kg per day • Recommendation of 500 kcal/kg per week to meet ACSM guidelines

15. Significant Correlations Average Daily Steps Energy Expenditure Barriers self-efficacy (r = .62) Task Self-efficacy (r = .77) Environment Exercise Partner (r = .71) Expectations & Values PA Enjoyment (r = .60) Negative Value (r = -.60) Observational Learning Role Model (r = .74) • Observational Learning • Role Model (r = .56)

16. Discussion • Large differences in results between objective and subject measures of PA • Self-report PA may be a better measure of leisure-time PA • SCT variables may be more import to leisure-time PA • Participants may have over reported their PA levels • 43% of participants were active exercisers before treatment • Self-Report PA • Social support, self-efficacy, self-regulation self-efficacy, and outcome expectancy predict PA • Pedometer measured PA • Role model predicts PA

17. Discussion • Strengths • Examined all of the components of SCT • Broke down each component into practical and measurable questions • Use both subjective and objective measures of PA • Limitations • Sample size • Many measures used single items • Measures weren’t empirically validated for use with the current sample • Cross-sectional study

18. Basen-Engquist et al., 2013 • Objective: • Determine if SCT variables, measured via questionnaires and ecological momentary assessment, predict PA in endometrial cancer survivors receiving a PA intervention • Sample: • 100 women • Diagnosed with Stage I, II, or IIIa endometrial cancer who were at least 6 month posttreatment and disease free • Excluded people meeting PA recommendations • Mean age of 57 years • Mean time since diagnosis 26 month • Mean BMI of 34.2 kg/m2

19. Methods • Participants recruited from gynecological oncology centers • Intervention • After baseline EMA data were collected and initial laboratory fitness assessment, participants received tailored PA recommendations with the ultimate goal of achieving ACSM PA guidelines • Procedure

20. Design: Assessment and Intervention Schedule Exercise prescription Lab Exercise and assessment Home-based Assessment Home-based Assessment T0: Baseline Weekly Telephone Counseling for Exercise Adherence Home-based Assessment Home-based Assessment Lab Exercise and assessment T1: 2 months Semi-Weekly Telephone Counseling for Exercise Adherence Home-based Assessment Home-based Assessment T2: 4 months Lab Exercise and assessment Monthly Telephone Counseling for Exercise Adherence Home-based Assessment Home-based Assessment T3: 6 months Lab Exercise and assessment

21. Methods • Measures • EMA Measures • Self-efficacy • Positive/Negative outcome expectancies • Self-reported PA (during/end of day) • Lab measures • Exercise self-efficacy • Barriers self-efficacy • Positive/Negative outcome expectations • Accelerometers

22. Results • Baseline PA (7 days) • Average of 14.5 mins of exercise per day • 46% of days no reported PA • 20% of days report > 30 min of PA • Question 1: Predicting daily PA minutes with same day SCT variables • Daily morning self-efficacy predicted same day minutes of PA (b = 5.98, p < .0001) • Daily positive outcome expectancy predicted same day minutes of PA (b = 3.93, p < .001) • Negative outcome expectancy did not predict same day PA mins

23. Results • Question 1: Predicting daily PA minutes with same day SCT variables • Self-efficacy X Time point interaction almost significant (p = .0879) • Self-efficacy had a stronger relation with PA at later time points • Previous day self-efficacy does not predict the next day PA minutes. • When self-efficacy and positive outcome expectancy were added together, only self-efficacy predicts same day PA minutes

24. Results • Question 2: Predicting PA with previous time point measures of SCT • Used laboratory assessment of • Exercise Self-efficacy • Barriers self-efficacy • Positive Outcome Expectancy • Negative Outcome Expectancy • Significant predictors • Exercise Self-efficacy (p < .0001) • Exercise Self-efficacy X Time point interaction (p < .001)

25. Discussion • Self-efficacy is an important predictor of PA for endometrial cancer survivors receiving a PA intervention • Self-efficacy was both a daily predictor of PA AND a predictor of future PA • Highlights the potential efficacy of an EMA intervention • Theoretical differences between EMA self-efficacy and longitudinal self-efficacy

26. Discussion • Strengths • EMA and longitudinal measures of SCT variables • Self-report and objective measures of PA • One of the first studies using SCT and endometrial cancer survivors • Limitations • Not an RCT so we do not no if effects were due to intervention • Drop out rates impacted sample size

27. Future Directions • Self-efficacy appears to be important • How do we change it • Conduct RCT’s for PA interventions • Timing is an important issue • Do we create dynamic interventions that target different variables at different time points • If so, which variables at what times • Continue to have methodological limitations • Focus more on causal determinants of PA

28. Future Directions • Are these predictors different for patients with different cancers, different cancer statuses (e.g., diagnosis, treatment, survivor), or different cancer treatments (e.g., chemo, radiation, surgery) • How do these predictors relate to the type, intensity, duration, and frequency of PA • Resistance training for breast cancer • Interval training • We have to be flexible and change theories and interventions as research develops