Associations among physical activity, body mass index, and health-related quality of life by race/ethnicity in a diverse sample of breast cancer survivors.

BACKGROUND: Health-related quality of life (HRQOL), body mass index (BMI), and physical activity (PA) levels have all been associated with prognosis following breast cancer and may explain partially the higher mortality for breast cancer in certain racial/ethnic subgroups. In this study, associations between PA, BMI, and HRQOL by race were examined in a sample of breast cancer survivors.
METHODS: Measures of PA, BMI, and HRQOL as well as demographic and medical characteristics of women (N = 3013, 13% nonwhite) who participated in the Women's Healthy Eating and Living Study were assessed at baseline. Analysis of covariance was used to examine the relationship between PA and obesity with HRQOL outcomes. Statistical tests were 2-sided.
RESULTS: African American women were less likely to meet guidelines for PA and more likely to be obese than women from other ethnic groups (P < .05). In adjusted models, women who met guidelines for PA reported significantly higher physical health composite (point differences ranged from 10.5 to 21.2 points, all P < .05) and vitality (point differences ranged from 9.9 to 16.5 points, all P < .05) scores than those who did not, regardless of race/ethnicity. Associations between obesity and HRQOL were mixed with fewer associations for Asian American and African American women and stronger associations for whites.
CONCLUSIONS: Breast cancer survivors from racially and ethnically diverse populations have lower levels of PA and higher rates of obesity that are generally associated with poorer HRQOL. Culturally sensitive PA and weight loss interventions may improve these lifestyle characteristics and result in improved HRQOL.