title: A pooled analysis of post-diagnosis lifestyle factors in association with late estrogen-receptor-positive breast cancer prognosis.
abstract: Lifestyle factors have been well studied in relation to breast cancer prognosis overall; however, associations of lifestyle and late outcomes (>5 years after diagnosis) have been much less studied, and no studies have focused on estrogen receptor-positive (ER+) breast cancer survivors, who may have high risk of late recurrence and mortality. We utilized a large prospective pooling study to evaluate the associations of lifestyle factors with late recurrence and all-cause mortality among 6,295 5-year ER+ Stage I-III breast cancer survivors. Pooled and harmonized data were available on clinical factors and lifestyle factors (pre- to post-diagnosis weight change, body mass index (BMI) (kg/m(2)), recreational physical activity, alcohol intake and smoking history), measured on average 2.1 years after diagnosis. Updated information for weight only was available. Study heterogeneity was evaluated by the Q-statistic. Multivariable Cox regression models were stratified by study. Adjusting for clinical factors and potential confounders, ≥ 10% weight gain and obesity (BMI, 30-34.99 and ≥ 35) were associated with increased risk of late recurrence (hazard ratios (95% confidence intervals): 1.24 (1.00-1.53), 1.40 (1.05-1.86) and 1.41 (1.02-1.93), respectively). Daily alcohol intake was associated with late recurrence, 1.28 (1.01-1.62). Physical activity was inversely associated with late all-cause mortality (0.81 (0.71-0.93) and 0.71 (0.61-0.82) for 4.9 to <17.4 and ≥ 17.4 metabolic equivalent-hr/week). A U-shaped association was observed for late all-cause mortality and BMI using updated weight (1.42 (1.15-1.74) and 1.40 (1.09-1.81), <21.5 and ≥ 35, respectively). Smoking was associated with increased risk of late outcomes. In this large prospective pooling project, modifiable lifestyle factors were associated with late outcomes among long-term ER+ breast cancer survivors.
authors.affiliation: Division of Epidemiology, Department of Medicine, Vanderbilt Epidemiology Center; and Vanderbilt-Ingram Cancer Center, Vanderbilt School of Medicine, Nashville, TN.
authors.forename: Sarah
authors.initials: S
authors.lastname: Nechuta
authors.affiliation: Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA.|Department of Medical Oncology, Dana Farber Cancer Institute, Boston, MA.
authors.forename: Wendy Y
authors.initials: WY
authors.lastname: Chen
authors.affiliation: Division of Epidemiology, Department of Medicine, Vanderbilt Epidemiology Center; and Vanderbilt-Ingram Cancer Center, Vanderbilt School of Medicine, Nashville, TN.
authors.forename: Hui
authors.initials: H
authors.lastname: Cai
authors.affiliation: Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Poole
authors.affiliation: Division of Research, Kaiser Permanente Northern California, Oakland, CA.
authors.forename: Marilyn L
authors.initials: ML
authors.lastname: Kwan
authors.affiliation: Cancer Prevention Program, Moores UCSD Cancer Center, University of California, San Diego, CA.
authors.forename: Shirley W
authors.initials: SW
authors.lastname: Flatt
authors.affiliation: Cancer Prevention Program, Moores UCSD Cancer Center, University of California, San Diego, CA.
authors.forename: Ruth E
authors.initials: RE
authors.lastname: Patterson
authors.affiliation: Cancer Prevention Program, Moores UCSD Cancer Center, University of California, San Diego, CA.
authors.forename: John P
authors.initials: JP
authors.lastname: Pierce
authors.affiliation: Division of Research, Kaiser Permanente Northern California, Oakland, CA.
authors.forename: Bette J
authors.initials: BJ
authors.lastname: Caan
authors.affiliation: Division of Epidemiology, Department of Medicine, Vanderbilt Epidemiology Center; and Vanderbilt-Ingram Cancer Center, Vanderbilt School of Medicine, Nashville, TN.
authors.forename: Xiao
authors.initials: X
authors.lastname: Ou Shu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000401:mortality* / Q000473:pathology*; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D008019:Life Style; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology; D016016:Proportional Hazards Models; D011960:Receptors, Estrogen / Q000096:biosynthesis; D012307:Risk Factors; D017741:Survivors; D055815:Young Adult
chemical_list: D011960:Receptors, Estrogen
keywords: breast cancer; cohort; lifestyle factors; mortality; prospective; recurrence