Jessica Dobek

Resistance Training Reduces Disability in Prostate Cancer Survivors on Androgen Deprivation Therapy: Evidence From a Randomized Controlled Trial

OBJECTIVES To investigate whether functionally based resistance exercise could improve strength, physical function, and disability among prostate cancer survivors (PCS) on androgen deprivation therapy (ADT); and to explore potential mediators of changes in outcomes from exercise. DESIGN Randomized controlled trial. SETTING Academic medical center. PARTICIPANTS PCS (N=51; mean age, 70.2y) on ADT. INTERVENTION PCS were randomized to moderate to vigorous intensity resistance training or stretching (placebo control) for 1 year. MAIN OUTCOME MEASURES Maximal leg press and bench press strength, objective and self-reported physical function, and self-reported disability. Hierarchical linear modeling was used to test for significant group × time differences adjusting for covariates. RESULTS Retention in the study was 84%, and median attendance to supervised classes was 84% in the resistance group. No study-related injuries occurred. Maximal leg strength (P=.032) and bench press strength (P=.027) were improved after 1 year of resistance training, whereas little change occurred from stretching. Self-reported physical function improved with resistance training, whereas decreases occurred from stretching (P=.016). Disability lessened more with resistance training than stretching (P=.018). One-year change in leg press strength mediated the relation between groups (resistance or stretching) and 1-year change in self-reported disability (P<.05). CONCLUSIONS One year of resistance training improved muscle strength in androgen-deprived PCS. Strengthening muscles using functional movement patterns may be an important feature of exercise programs designed to improve perceptions of physical function and disability. Findings from this study contribute to the mounting evidence that exercise should become a routine part of clinical care in older men with advanced prostate cancer.

Skeletal Response to Resistance and Impact Training in Prostate Cancer Survivors

INTRODUCTION Androgen deprivation therapy (ADT) is associated with significant bone loss and an increase in fracture risk among prostate cancer survivors (PCS). We investigated whether impact + resistance training could stop ADT-related declines in bone mineral density (BMD) among PCS on ADT. METHODS We randomized 51 PCS (mean age, 70.2 yr) currently prescribed ADT to participate in 1 yr of impact + resistance training (Prevent Osteoporosis with Impact + Resistance (POWIR)) or in an exercise placebo program of stretching exercise (FLEX). Outcomes were proximal femur (total hip, femoral neck, and greater trochanter) and spine (L1-L4) BMD (g·cm) and bone turnover markers (serum osteocalcin (ng·mL) and urinary deoxypyrodinoline cross-links (nmol·mmol Cr)). RESULTS Retention in the 1-yr study was 84% and median attendance to supervised classes was 84% in POWIR and 74% in FLEX. No study-related injuries were reported. There were no significant differences between groups for average L1-L4 BMD or for BMD at any hip site. When examining individual vertebrae, POWIR has a significant effect on preservation of BMD (-0.4%) at the L4 vertebrae compared with losses (-3.1%) in FLEX (P = 0.03). CONCLUSION Impact + resistance training was a safe and acceptable form of exercise for older PCS on ADT. Among our limited sample, POWIR did not appear to have a clinically meaningful effect on hip or spine BMD, but some evidence of skeletal adaptation to resistance + impact training in an androgen-deprived state was apparent. Future studies need to be conducted on a larger sample of patients and should consider modifications to POWIR that could further enhance loading across the spine and at the hip to preserve BMD at these clinically relevant sites.

Frailty in Older Breast Cancer Survivors: Age, Prevalence, and Associated Factors

PURPOSE/OBJECTIVES To describe frailty and associated factors in breast cancer survivors (BCSs) and evaluate whether BCSs are frail at an earlier age than female participants from in two large epidemiological studies. DESIGN Descriptive, cross-sectional. SETTING School of Nursing at Oregon Health and Science University. SAMPLE 216 BCSs aged 53-87 years who were a mean 5-7 years post-treatment and not currently participating in exercise. METHODS Performance tests, clinical measures, and self-reported questionnaires provided baseline data on five criteria for frailty. MAIN RESEARCH VARIABLES Frailty was defined as meeting three of the five criteria of the frailty phenotype: shrinking, exhaustion, low activity, slowness, and weakness. Data were compared to published data from women in the Cardiovascular Health Study (CHS) and Womens Health and Aging Study (WHAS). FINDINGS Eighteen percent of BCSs aged 70-79 years were frail compared to 11% of women of the same age in the CHS and WHAS. Frailty was more common at a younger age in BCSs, and more BCSs were frail in all age groups compared to women in the CHS study until about age 80 years, when prevalence of frailty was similar in the two groups. Fifty percent of BCSs were classified as prefrail because they met one or two of the five frailty criteria. Higher body mass index increased the odds of frailty, and higher physical activity decreased the odds of frailty (odds ratio [OR] = 1.12, p = 0.003, and OR = 0.99, p = 0.000, respectively). CONCLUSIONS Frailty and prefrailty may be common in BCSs and may occur at an earlier age than in adults without a history of breast cancer. IMPLICATIONS FOR NURSING Nurses should be alert to prefrailty or frailty at a younger age in BCSs. Awareness and early intervention may delay or prevent frailty. KNOWLEDGE TRANSLATION BCSs may be frail even when they are not yet considered older adults. Prefrailty in BCSs is important to recognize because it suggests impending frailty that could lead to reduced physical functioning or poor health. Prefrailty and frailty could be assessed in BCSs aged 50 years and older in a clinical setting using a few questions about weight, fatigue, and activity levels, in addition to simple tests of walking speed and grip strength, if warranted.