Diabetes mellitus and incidence and mortality of colorectal cancer: a systematic review and meta-analysis of cohort studies

Abstract

Increasing evidence suggests that a history of diabetes mellitus (DM) may be associated with an increased risk of colorectal cancer (CRC). To provide a quantitative assessment of the association between DM and risk of CRC, We evaluated the relation between DM and incidence and mortality of CRC in a systematic review of cohort studies. Full publications of cohort studies were identified in MEDLINE, EMBASE and Science Citation Index Expanded, through February 28, 2011. Summary relative risks (SRRs) with 95% confidence intervals (CIs) were summarized using a random-effects model. Between-study heterogeneity was assessed using the Cochran's Q and I2 statistics. A total of 41 cohort studies (35 articles) were included in this systematic review. Combining 30 cohort studies which presented results on diabetes and CRC incidence, diabetes was associated with an increased incidence of CRC (SRRs 1.27, 95% CI: 1.21-1.34), with evident heterogeneity among studies (P=0.002, I2=48.4%). Subgroup analysis and meta-regression analysis by controlling the confounders showed that the increased incidence of CRC was independent of geographic locations, sex, family history of colorectal cancer, smoking, physical activity and body mass index. Diabetes was also positively associated with CRC mortality (SRR 1.20, 95% CI: 1.03-1.40), with evidence of heterogeneity between studies (P<0.001, I2=81.4%). Results from this systematic review support that compared to non-diabetic individuals, diabetic individuals have an increased risk of CRC.

Colorectal Cancer Screening in First Nations People Living in Manitoba

“…The disparities identified in FOBT, colonoscopy, and FS use are likely related to many factors and suggest that barriers to CRC screening exist for First Nations individuals. Addressing these barriers and improving CRC screening rates are particularly important since the incidence of CRC in First Nations is increasing and First Nations people have higher rates of diabetes and obesity which also increase the risk of CRC (11,(40)(41)(42).…”

The Effect of Metformin on Colorectal Carcinoma in Type 2 Diabetes Mellitus Patients: A Markov Model Analysis

“…The cycle length was set to be one year, which was the pertinent interval to observe the treatment response of tumor episodes. Further, in consideration of obtaining sustained outcomes and the actual life expectancy of T2DM patients, we assumed the patients to be observed for 11 years [18]. Then, the half-cycle correction was used [19].…”

“…Transition probabilities between each state in this model were extracted from the included literatures published in English that investigated the therapeutic efficacy of metformin and/or other T2DM medications on CRC for T2DM patients without CRC (Table 1) [18,[22][23][24][25][26][27][28][29][30]. Literatures were retrieved from two databases of PubMed and Cochrane Library with the latest searching on September 27, 2016.…”

Diabetes and Cancer: Is there a Link?

“…Studies show an increased risk in type 2 diabetic patients for colon, breast, liver, pancreas, bladder cancers and non-Hodgkin's lymphoma [6][7][8][9][10][11][12], and a decrease risk for prostate cancer [13]. Lung cancer does not appear to be related to diabetes and for renal cancer data are inconclusive [14].…”