TOPLINE:
METHODOLOGY:
- Some studies suggest that multivitamin supplements might increase a person’s risk for CRC, and other research indicates that certain components of multivitamins, such as vitamins C and D, may have anti-CRC properties.
- Because as many as half of CRC survivors take a multivitamin, researchers wanted to assess whether multivitamin use affects overall survival among people with CRC.
- In the current prospective cohort study, researchers evaluated the use and dose of multivitamin supplements in 2424 patients with stages I-III CRC, using detailed information from patients in the Nurses’ Health Study and Health Professionals Follow‐Up Study.
- The participants completed a mailed questionnaire every 2 years, which included questions about the current use of multivitamin supplements as well as doses per week (0, 1-2, 3-5, 6-9, and ≥ 10 tablets).
- The researchers assessed the potential association between multivitamin use and CRC-related as well as all‐cause mortality.
TAKEAWAY:
- Over a median follow-up period of 11 years, 1512 deaths and 343 cancer-specific deaths occurred.
- For patients diagnosed with CRC, a moderate dose of multivitamins (three to five tablets per week) vs no multivitamin use was associated with a 45% lower risk for cancer-related mortality (adjusted hazard ratio [aHR], 0.55; P = .005).
- Moderate multivitamin use was also associated with a lower risk for all-cause mortality (aHR, 0.81; P = .04) as was a higher dose of six to nine tablets per week (aHR, 0.79; P < .001).
- However, high doses of 10 or more tablets per week were associated with a 60% higher risk for cancer-related mortality (aHR, 1.60; P = .02).
IN PRACTICE:
The study findings suggested that moderate multivitamin supplement use may come with a survival benefit in patients with CRC, while high doses may not, but “further studies are needed before making clinical recommendations for multivitamin use in patients with CRC,” the authors said.
SOURCE:
This work, led by Ming‐ming He of Sun Yat‐sen University Cancer Center, Guangzhou, China, was published in Cancer.
LIMITATIONS:
Given the study’s observational design, residual confounding may be possible. Reverse causation and recall bias are also possible limitations.
DISCLOSURES:
This study was funded by the National Institutes of Health, American Institute for Cancer Research, Wellesley College, Dana‐Farber Cancer Institute, and the Entertainment Industry Foundation. Three study authors reported financial relationships outside this work.
A version of this article appeared on Medscape.com.