Colorectal cancer is the third most common form of cancer and the fourth most common cause of cancer-related deaths in the US. Researchers from a recent study published in the European Journal of Epidemiology discovered that vitamin D deficiency was associated with worse outcomes and higher mortality rates in colorectal cancer patients.
From 2003-2010, researchers from the DACHS-study recruited a total of 2,910 colorectal cancer patients from 22 medical clinics throughout Germany. All patients underwent medical examinations and released information regarding the state and severity of their cancer. Additionally, blood draws were taken approximately three days after recruitment to establish serum 25(OH)D status. Patients were followed for the course of their cancer for five years and all cases of remission and mortality were recorded.
This is what the researchers found:
- The average vitamin D level was 12.12 ng/ml (30.3 nmol/L).
- A total of 59% of the participants had vitamin D levels less than 12 ng/ml (30 nmol/L), 25% had vitamin D levels between 12-20 ng/ml (30-50 nmol/L) and only 16% had levels above 20 ng/ml (50 nmol/L).
- When comparing the highest vitamin D levels to the lowest, researchers discovered patients with higher vitamin D levels:
- Had a 1.78 times decreased risk of all cause mortality (p<0.001).
- Had a 1.65 times decreased risk of colorectal cancer mortality (p=0.002).
- Were 1.32 times more likely to experience recurrence-free survival (p=0.0094).
- Were 1.48 times more likely to experience disease-free survival (p<0.001).
The researchers concluded:
“…Our study supports and extends evidence for an inverse relationship between serum 25(OH)D3 levels and colorectal cancer prognosis in the range of 25(OH)D3 levels less than 30 nmol/L, which are seen in the majority of colorectal cancer patients.”
Maalmi, H. et al. Relationship of very low serum 25-hydroxyvitamin D3 levels with long-term survival in a large cohort of colorectal cancer patients from Germany. European Journal of Epidemiology, 2017.