Longitudinal Changes in Sports Activity From Pre-diagnosis to First Five Years Post-diagnosis: a Prospective Chinese Breast Cancer Cohort Study

Abstract

Background: To compare change in level of physical activitybetween pre-and post- diagnosis of breast cancer in Chinese women.Methods:Based on an on-going prospective study consisting of 1462 Chinese women with early-stage breast cancer, a validated modified Chinese Baecke questionnaire was used to measure physical activity at baseline (12 months before cancer diagnosis), 18-, 36- and 60-months after diagnosis (over the previous 12 months before each interview). Results:The overall physical activity level at post-diagnosis was 5.8 MET-hours/week, which was significantly higher than that at pre-diagnosis at a median level of 0.6 MET-hours/week (P <0.001).The median levels of physical activity at 18-, 36- and 60-months follow-up were5.3, 4.4 and 3.9 MET-hours/week, respectively. There was no significant difference between any two of the three follow-ups at post-diagnosis. The proportions of participant who met WCRF/AICR recommendation before and after cancer diagnosis were both low, being 20.7% and 35.1%, respectively.Compared to pre-diagnosis, most of the patients improved or had no change on level of physical activity at post-diagnosis, with the respective proportion being 48.2% and 43.8%. Conclusions:Adherence to current lifestyle recommendation for cancer survivors, Chinese women with breast cancer significantly increasedlevel of physical activity level after cancer diagnosis, and such improvement was sustained to five years post-diagnosis. The proportion of patients who met the exercise recommendation for cancer survivors was still low. Encouraging patients on the importance of durable high level of physical activity in breast cancer survivorship is warranted.