Associations Between Domain-specific Physical Activity Levels And Physical Characteristics Of Behavior In Newly Diagnosed Breast Cancer Patients

PURPOSE: Physical activity (PA) is a complex behavior occurring in several life-domains (household, occupation, transport, recreation) each of which may confer distinct health benefits. Here, we associate self-reported PA domains with physical characteristics of behavior measured by devices (sitting, standing, stepping, PA intensity) in breast cancer patients. METHODS: The Alberta Moving Beyond Breast Cancer (AMBER) study is a prospective cohort of 1,528 newly diagnosed breast cancer patients. We examined 1,363 participants who wore ActiGraph (AG, hip) and activPAL (aP) devices for 1-7 days and completed the domain specific Past Year Total Physical Activity Questionnaire. AG data estimated time in light- (LIPA) and moderate-vigorous intensity PA (MVPA). aP data estimated sedentary, standing, and stepping time, and step counts. Age adjusted linear regression models calculated differences in device metrics between participants in the least (Q1) and most active (Q5) quintiles of each domain. RESULTS: Mean age was 55 (SD = 11) years, and most participants (91%) were diagnosed with stage I/II disease. Of 347 min/d of total PA reported, most was reported in the household (53%), then occupational (30%), recreational (16%) and transport (1%) domains. Of the 858 min/d spent awake, most aP time was sedentary (63%), then standing (27%) and stepping (10%), with a mean 7,349 steps/d. Most AG active time was LIPA (31% time awake), then MVPA (7%). Those reporting the most household activity (Q5 vs. Q1) had significantly (p < 0.05) less sedentary time (-53 min/d) and more standing (+46 min/d) and LIPA (+34 min/d), but not more MVPA or steps. Active transport was associated with less sedentary time (-15 min/d) and more stepping (+7 min/d), MVPA (+6 min/d) and steps (+872 steps/d). Those reporting the most recreational activity were less sedentary (-33 min/d) and more active for each physical characteristic (e.g., LIPA +22 min/d; MVPA +30 min/d; +3,101 steps/d). CONCLUSIONS: Individuals newly diagnosed with breast cancer reporting the most household activity were less sedentary and did more standing and LIPA, but not greater MVPA or stepping. In contrast, those reporting active transport and more recreational activity were more active across all physical characteristics of behavior, particularly activities involving stepping. This study was funded by a Team Grant (#107534), a Project Grant (#155952), and a Foundation Grant [#159927] from the Canadian Institutes of Health Research