Diabetes mellitus type 2 and subsite-specific colorectal cancer risk in men and women: results from the Netherlands Cohort Study on diet and cancer.
BACKGROUND
Type 2 diabetes mellitus (T2DM) is associated with an increased risk of colorectal cancer (CRC); however, studies differentiating between subsites of CRC are limited. We investigated how diabetes mellitus (DM) was associated with subsite-specific CRC risk in men and women.


METHODS
The Netherlands Cohort Study on diet and cancer is a prospective study among 120 852 men and women aged 55-69 years old at baseline in 1986. Information on DM, anthropometric, dietary and lifestyle factors was self-reported at baseline. T2DM was defined as the diagnosis of DM after 30 years of age. Incident CRC cases were identified by record linkage with the Netherlands cancer registry and the Dutch pathology registry. After 17.3 years of follow-up, 1735 incident male CRC cases and 1321 female CRC cases were available for analyses. Subsite-specific hazard ratios (HRs) for CRC were estimated in case-cohort analyses using Cox regression.


RESULTS
At baseline, 3.1% of subcohort members reported T2DM, of whom 80% were diagnosed after 50 years of age. Multivariable-adjusted models showed that the risk of proximal colon cancer was significantly increased in women with T2DM versus women without T2DM (HR=1.80, 95% confidence interval: 1.10-2.94). There was no association between T2DM and the risk of overall CRC, distal colon cancer and rectal cancer in women. In men, T2DM was not associated with overall CRC (HR=0.98, 95% confidence interval: 0.64-1.50), or with risk at any subsite.


CONCLUSIONS
This prospective study showed an increased risk of proximal colon cancer in women with T2DM compared with non-T2DM women.
aDepartment of Epidemiology, GROW - School for Oncology and Developmental Biology, CAPHRI School for Public Health and Primary Care, and CARIM School for Cardiovascular Diseases Maastricht University bDepartment of Internal Medicine, Division of Gastroenterology and Hepatology, Maastricht University Medical Centre, Maastricht cDepartment of Prevention and Health, TNO Quality of Life, Leiden Departments of dPathology eClinical Epidemiology, VieCuri Medical Centre, Venlo, The Netherlands.
Sander
S
de Kort
C C J M
CC
Simons
Piet A
PA
van den Brandt
R Alexandra Sandra
RA
Goldbohm
Ilja C W
IC
Arts
Adriaan P
AP
de Bruine
Maryska L G
ML
Janssen-Heijnen
Silvia
S
Sanduleanu
Ad A M
AA
Masclee
Matty P
MP
Weijenberg
D000328:Adult; D017668:Age of Onset; D000368:Aged; D016009:Chi-Square Distribution; D015179:Colorectal Neoplasms / Q000453:epidemiology* / Q000473:pathology*; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis / Q000453:epidemiology*; D004032:Diet / Q000009:adverse effects; D005260:Female; D006801:Humans; D015994:Incidence; D008019:Life Style; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009426:Netherlands / Q000453:epidemiology; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012042:Registries; D018570:Risk Assessment; D012307:Risk Factors; D017678:Sex Distribution; D012737:Sex Factors; D013997:Time Factors