Alok A. Khorana, MDDisclosures
October 20, 2014
Calcium, Vitamin D, Dairy Products, and Mortality Among Colorectal Cancer Survivors: The Cancer Prevention Study-II Nutrition Cohort
Yang B, McCullough ML, Gapstur SM, et al
J Clin Oncol. 2014;32:2335-2343
Study Summary
Diet and lifestyle changes may play an important role in cancer pathogenesis. Yang and fellow American Cancer Society investigators analyzed the role of calcium, vitamin D, and dairy product intake before and after diagnosis of nonmetastatic colorectal cancer. The study population comprised 2284 participants in a prospective cohort study.
In multivariate analysis, post-diagnosis total calcium intake was inversely associated with all-cause mortality (relative risk [RR] for those in the highest relative to the lowest quartiles, 0.72; 95% confidence interval [CI], 0.53-0.98; Ptrend = .02). An inverse association with all-cause mortality was also observed for postdiagnosis milk intake (RR, 0.72; 95% CI, 0.55-0.94; Ptrend = .02), but not for vitamin D intake. Prediagnosis intakes were not associated with mortality.
Viewpoint
Diet and modifiable lifestyle factors are important issues for survivors of localized colorectal cancer. Unfortunately, randomized trials in this setting are difficult to conduct, require prolonged follow-up, and may not be able to control for all lifestyle factors. Therefore, data from well-conducted prospective cohort studies may be good enough to make recommendations to patients.
This study suggests that increased milk and calcium intake is associated with improved outcomes. Limitations include the primarily white study population with known higher rates of lactase persistence; in addition, the lack of association with vitamin D intake is inconsistent with prior reports.[1] Increased milk and calcium intake, along with reduced red meat intake and regular exercise, can be discussion points for survivors of colorectal cancer interested in modifiable lifestyle risk factors.
Calcium, vitamin D, dairy products, and mortality among colorectal cancer survivors: the Cancer Prevention Study-II Nutrition Cohort.
J Clin Oncol. 2014; 32(22):2335-43 (ISSN: 1527-7755)
Yang B; McCullough ML; Gapstur SM; Jacobs EJ; Bostick RM; Fedirko V; Flanders WD; Campbell PT
PURPOSE: Higher calcium, vitamin D, and dairy product intakes are associated with lower colorectal cancer incidence, but their impacts on colorectal cancer survival are unclear. We evaluated associations of calcium, vitamin D, and dairy product intakes before and after colorectal cancer diagnosis with all-cause and colorectal cancer-specific mortality among colorectal cancer patients.
PATIENTS AND METHODS: This analysis included 2,284 participants in a prospective cohort who were diagnosed with invasive, nonmetastatic colorectal cancer after baseline (1992 or 1993) and up to 2009. Mortality follow-up was through 2010. Prediagnosis risk factor information was collected on the baseline questionnaire. Postdiagnosis information was collected via questionnaires in 1999 and 2003 and was available for 1,111 patients.
RESULTS: A total of 949 participants with colorectal cancer died during follow-up, including 408 from colorectal cancer. In multivariable-adjusted Cox proportional hazards regression models, postdiagnosis total calcium intake was inversely associated with all-cause mortality (relative risk [RR] for those in the highest relative to the lowest quartiles, 0.72; 95% CI, 0.53-0.98; Ptrend = .02) and associated with marginally statistically significant reduced colorectal cancer-specific mortality (RR, 0.59; 95% CI, 0.33 to 1.05; Ptrend = .01). An inverse association with all-cause mortality was also observed for postdiagnosis milk intake (RR, 0.72; 95% CI, 0.55 to 0.94; Ptrend = .02), but not vitamin D intake. Prediagnosis calcium, vitamin D, and dairy product intakes were not associated with any mortality outcomes.
CONCLUSION: Higher postdiagnosis intakes of total calcium and milk may be associated with lower risk of death among patients with nonmetastatic colorectal cancer.
References
- Zgaga L, Theodoratou E, Farrington SM, et al. Plasma vitamin D concentration influences survival outcome after a diagnosis of colorectal cancer. J Clin Oncol. 2014;32:2430-2439. Abstract