Physical Activity and its Association with Health-related Quality of Life in Native American Cancer Survivors

Abstract

PURPOSE: To identify the amount, intensity, and types of physical activity (PA) in a national sample of Native American cancer survivors (NACS) and to examine the relationship between PA and health-related quality of life (HQOL). METHODS: Between July 2013 and September 2014, 63 NACS of all types completed a web-based questionnaire regarding their health history, cancer-specific outcomes, HQOL, and PA. Frequency, duration, and intensity of various PA types, including traditional activities specific to NA, done in a typical week during the previous month were assessed. Descriptive statistics were used to explore PA and ANCOVA was used to evaluate the relationship between PA and HQOL. RESULTS: After exclusion for missing covariates, the final analytic sample consisted of 55 subjects, 40% of which were breast cancer survivors, 48% female, 69% between ages 55-74, and 92% being diagnosed within one year of completing the survey. The majority of NACS (69%) did not meet current PA guidelines of 150 min/wk of moderate-to vigorous-intensity PA (MVPA). Survivors participated in 3116 ± 3872 MET-min/wk (mean ± SD) of total PA. When categorized by level of intensity, survivors accumulated 2113 ± 3241 MET-min/wk of MVPA and 999 ± 988 MET-min/wk of light-intensity PA. Regarding type of PA, NACS participated in 1202 ± 1571 MET-min/wk of non-exercise PA and 1207 ± 1660 MET-min/wk of planned exercise, as well as 1823 ± 2076 MET-min/wk of non-traditional PA and 586 ±1123 MET-min/wk of traditional NA PA. Walking was the most common PA (91% participated), followed by light- (87%) and moderate- (53%) intensity housework. After adjustment for relevant covariates, meeting current PA guidelines was not associated with physical function (p=0.21), fatigue (p=0.12), pain (p=0.28), sleep health (p=0.15), social functioning (p=0.63), emotional (p=0.26), or spiritual QOL (p=0.31). CONCLUSIONS: Less than one third of NACS are meeting PA guidelines. While this sample performed more MVPA than light-intensity PA, this could be due to the number of MVPA activities surveyed (n=27) vs. light-intensity activities (n=9). These survivors tend to participate in non-traditional PA such as walking. Results also suggest that meeting PA guidelines is not associated with greater HQOL in this sample of NACS.