Several novel risk factors and potential protective factors associated with serrated polyposis syndrome (SPS) and colorectal cancer (CRC) have been identified in an Australian study.
Researchers at the University of Melbourne found evidence of a potentially protective role for folate, calcium and NSAIDs use, as well as low to moderate alcohol intake and HRT in the development of SPS and CRC.
In a case control study they compared data from 350 individuals with SPS from the Genetics of Colonic Polyposis Study and 714 control subjects from the Australasian Colorectal Cancer Family Registry
Their findings, published in BMC Gastroenterology (link here) showed that as in previous studies, female sex, increasing body mass index (BMI) and smoking were significant risk factors for the development of SRS.
However, increasing weekly folate and NSAIDs intake decreased the odds of SPS by 18% and 9% respectively. And in female subgroup analysis the use of HRT supplements was associated with a 56% decreased odds of SPS.
The researchers also stratified the risk of SPS based on the 2010 WHO criteria.
They found that increasing calcium and folate intake decreased the odds of fulfilling WHO criterion I SPS (at least 5 serrated polyps proximal to the sigmoid Colon, 2 of which are > 10 mm in diameter) by 21 and 16%, respectively.
Similarly, folate and NSAIDs intake reduced the risk of fulfilling both SPS WHO criteria by 18 and 12%, respectively.
And in a novel finding, low to moderate alcohol consumption ( 1–100 g of alcohol per week) was associated with a reduced risk of fulfilling WHO criterion III compared to no alcohol .
Conversely, use of lipid lowering medication in women was strongly associated with fulfilling both WHO criteria (OR = 12.62).
Almost one in four of the participants with SPS (23.4%) developed colorectal cancer, and the researchers found that regular use of NSAIDs may have a protective effect. Every extra NSAID dose per week compared with controls was associated with a 19% reduction in the odds of CRC.
“These findings, combined with findings from other studies that identified BMI, blood lipid lowering medication and female biological sex as risk factors for serrated polyps, could assist with risk stratification for prevention and screening strategies specific for patients with different SPS phenotypes,” they wrote.
“Incorporation of these modifiable factors into current risk stratification algorithms for SPS management could help reduce colonoscopy burden in those at lower risk of CRC, whilst increasing attention to those at greater risk of developing CRC.”