Nut consumption associated with survival benefit among long-term breast cancer survivors
Click Here to Manage Email Alerts
Nut consumption appeared associated with higher survival rates among long-term breast cancer survivors and should be emphasized as a modifiable lifestyle factor in survivor guidelines, according to a study in International Journal of Cancer.
“As nutrient-dense foods incorporated in healthy diets, nuts have been found in several cohort studies to be associated with reduced all-cause and cause-specific mortality, particularly mortality due to cardiovascular diseases, in the general population,” Xiao-Ou Shu, MD, PhD, Ingram professor of cancer research and associate director for global health at Vanderbilt Ingram Cancer Center, and professor of medicine at Vanderbilt University School of Medicine, told Healio. “However, little is known whether the health benefits of nut intake can be extended to breast cancer survivors, particularly regarding the DFS. Our study was conducted to address this knowledge gap.”
Shu and researchers from Vanderbilt University Medical Center and the Shanghai Municipal Center of Disease Control and Prevention analyzed associations of peanut and tree nut consumption with OS and DFS among 3,449 long-term breast cancer survivors aged 20 to 75 years who participated in the Shanghai Breast Cancer Survival Study. Of them, 3,148 women (mean age at diagnosis, 53.36 years) reported nut consumption and 301 women (mean age at diagnosis, 55.61 years) reported no nut consumption.
Researchers obtained a detailed dietary assessment, which the women completed at the 5-year post-diagnosis follow-up interview between October 2007 and October 2011. The investigators converted consumption of nuts into grams per week and calculated total nut consumption as the sum of intake from peanuts, walnuts and other nuts.
Median follow-up after dietary assessment was 8.27 years, during which time 374 deaths occurred, including 252 due to breast cancer.
Results showed regular nut consumers had higher rates of OS (93.7% vs. 89%) and DFS (94.1% vs. 86.2%) at 5-year post-dietary assessment (ie, 10 years after diagnosis). Following multivariable adjustment, researchers observed positive associations of nut consumption with OS (P for trend = .022) and DFS (P for trend = .003) after a dose-response pattern (HR for OS = 0.72; 95% CI, 0.52-1.05; HR for DFS = 0.48; 95% CI, 0.31-0.73) for participants with greater-than-median (17.32 g per week) nut intake compared with nonconsumers.
Stratified analyses indicated the associations were more evident among women with higher total energy intake for OS (P for interaction = .02) and among those with early-stage breast cancers for DFS (P for interaction = .04). Associations did not vary by nut type and the nut-DFS associations were not modified by ER/PR status or other known prognostic factors, researchers wrote.
“We found that nut and DFS association was more evident among participants with early-stage (I-II) breast cancers. Education targeting this group of survivors may yield the most significant impact,” Shu told Healio.
Study limitations included self-reported recurrence and metastasis status, a limited statistical power for stratified analyses due to a small number of events in the subgroup of patients, and that the nut consumption information was collected all at once; thus, any changes in nut consumption could not be captured.
“Studies from different populations are needed to confirm our findings,” Shu said. “Randomized clinical trials are required to draw a firm conclusion.”
For more information:
Xiao-Ou Shu, MD, PhD, can be reached at Vanderbilt Epidemiology Center, Vanderbilt University Institute of Medicine and Public Health, 2525 West End Ave., Suite 600, Nashville, TN 37203-1738; email: xiao-ou.shu@vanderbilt.edu.
Collapse
Read more about
Click Here to Manage Email Alerts