Craft, L. L., Vaniterson, E. H., Helenowski, I. B., Rademaker, A. W., & Courneya, K. S. (2012). Exercise effects on depressive symptoms in cancer survivors: a systematic review and meta-analysis. Cancer Epidemiology, Biomarkers & Prevention : A Publication of the American Association for Cancer Research, Cosponsored by the American Society of Preventive Oncology, 21(1), 3-19.

Evaluate the current literature on antidepressant effects of exercise in cancer survivors. Also to explore potential moderating variables related to participant, cancer and exercise characteristics.

TYPE OF STUDY Combined systematic review and meta analysis

DATABASES Medline, Medline in Process, Psycinfo, Embase, CINAHL, Cochrane database, Cochrane central register of controlled trials, Allied and Complementary Medicine, Biosis Previews, Sports Discus
   

KEYWORDS  terms related to cancer, exercise, and depression    

INCLUSION CRITERIA Studies were eligible if they were a RCT of adults with cancer, compared exercise program with usual care, exercise program was chronic in nature (at least 4 weeks), reported depression pre and post  intervention, used depression inventory or clinician interview to define depression symptom, English language

EXCLUSION CRITERIA studies that used quality of life or moods scales to measure depression
Study Aims Evaluate the current literature on antidepressant effects of exercise in cancer survivors. Also to explore potential moderating variables related to participant, cancer and exercise characteristics.  
 

TOTAL REFERENCES RETRIEVED : N =60

METHOD OF STUDY EVALUATION AND COMMENTS ON LITERATURE USED Two investigators independently reviewed articles with discrepancies resolved by consensus.

All studies included aerobic exercise with some also including strength training. Exercise programs were implemented prior to or during treatment in 47% of the studies. Interventions varied from unsupervised home based to supervised facility based with frew having mixed supervision. Intervention length ranged mostly from 4-14 weeks, with the longest being 52 weeks.  
 

FINAL NUMBER STUDIES INCLUDED: N = 14 articles describing 15 RCTS   TOTAL SAMPLE SIZE: N =  1371   SAMPLE RANGE ACROSS STUDIES : 18-209, including exercise and control groups combined

KEY SAMPLE CHARACTERISTICS 60% (9) studies included breast cancer survivors. The average age was 51.6 years. 76.9 of those who reported race/ethnicity were Caucasian. Of those reporting cancer stage, 75% were patients with non-metastatic disease.

PHASE OF CARE Active Treatment

APPLICATIONS Late Effects and Survivorship

Effect size of -.22(p=0.04) was found comparing exercise group to control groups. Home based exercise had increased depressive symptoms (effect size(ES)e 0.16) compared to exercise location and facilities, laboratories, gyms (ES= -0.45, -0.77, -.014). Supervised exercise had the greatest effect (ES=-0.67) compared to mixed supervision (ES=-0.32) and unsupervised activity showed a small increase in depression (ES=0.25). Duration of greater than 30 minutes had a larger effect (ES=-.57) compared to less than or equal to 30 minutes (ES=0.01)

Overall, exercise had a small to moderate impact on depression symptoms which varied based on location of exercise, supervision, and duration. 

Exercise at places where patients interact with others had a greater effect size associated with reduction of depression symptoms. It would be important to recognize this when intervening with exercise. Future research should measure the significance of social interaction during exercise and depression symptoms.  Also, more work is necessary to understand if the exercise intervention improves QOL.