Metabolic Syndrome and Risks of Colon and Rectal Cancer: the European Prospective Investigation into Cancer and Nutrition Study
A partir de données de la cohorte EPIC portant sur 1 093 cas et 1 093 témoins, cette étude allemande évalue l’association entre le syndrome métabolique et le risque de cancer du côlon ou du rectum
Metabolic syndrome (MetS) is purportedly related to risk of colorectal cancer, however the association of MetS, as defined according to recent international criteria, and colorectal cancer has not been yet evaluated. In particular, it remains unclear to what extent the MetS components individually account for such an association. We addressed these issues in a nested case-control study that included 1,093 incident cases matched (1:1) to controls using incidence-density sampling. Conditional logistic regression was used to estimate relative risks (RRs) and 95% confidence intervals (CIs). MetS was defined according to the criteria of the National Cholesterol Education Program/Adult Treatment Panel III (NCEP/ATPIII), the International Diabetes Federation and the 2009 harmonized definition. Among individual components, abdominal obesity (RR=1.51;95%CI:1.16-1.96) was associated with colon cancer; whereas abnormal glucose metabolism was associated with both colon (RR=2.05; 95%CI:1.57-2.68) and rectal cancer (RR=2.07;95%CI:1.45-2.96). MetS as defined by each of the definitions was similarly associated with colon cancer (e.g.RR=1.91;95%CI:1.47-2.42 for MetS by NCEP/ATPIII); whereas MetS by NCEP/ATPIII, but not IDF or harmonised definition was associated with rectal cancer (RR=1.45;95%CI:1.02-2.06). Overall, these associations were stronger in women compared with men. However, the association between MetS and colorectal cancer was accounted for by abdominal obesity and abnormal glucose metabolism, such that MetS did not provide risk information beyond these components (likelihood ratio test P=0.10 for MetS by NCEP/ATPIII). These data suggest that simple assessment of abnormal glucose metabolism and/or abdominal obesity to identify individuals at colorectal cancer risk may have higher clinical utility compared to applying more complex MetS definitions.