title: Colorectal cancer risk prediction  and risk-adapted colorectal cancer screening  in patients with diabetes mellitus
creator: Ali Khan, Uzair
description: Colorectal cancer is currently the third most common and the second most deadly of all cancers.  Despite the success of global colorectal cancer screening programs in reduction of both  incidence and mortality, in recent decades the incidence in young individuals, particularly before  the age of 50, has risen in several countries. Resultantly, there is a call for colorectal cancer  screening programs to alter screening recommendation and identify risk factors that make young  people susceptible. Diabetes is a disease that has also been rising in young people in recent  decades. Additionally, diabetes shares several risk factors with colorectal cancer and has been  associated with colorectal cancer in some studies. Hence, it becomes increasingly important to  determine if diabetic patients are at increased risk and if they should be directed for an earlier  screening than the general population.  This study aimed to investigate the associations between diabetes and early-onset and late-onset  colorectal cancer and determine what effect age of diabetes diagnosis, family history of  colorectal cancer, and sex have on these associations. In addition, if diabetic patients are at  increased risk of colorectal cancer, it aimed to provide evidence-based risk-adapted screening  ages in diabetic patients with and without a family history of colorectal cancer, given that  diabetes has yet to be mentioned in global screening guidelines.  The analysis was conducted using the Swedish family-cancer datasets, the world’s largest of  their kinds with record linkage to the Swedish Inpatient and Outpatient Registers. The study  population consisted of 12,614,256 individuals with valid genealogical information (at least one  first-degree relatives) and up to 52 years of follow-up spanning from 1964 to 2015. Among the    12.6 million individuals, 559,375 cases of diabetes and 162,226 cases of colorectal cancer were  identified. Standardized incidence ratios, lifetime cumulative risk (age 0 to 79), and 10-year  cumulative risk of colorectal cancer in diabetic patients with and without a family history of  colorectal cancer were calculated. Both family and personal disease histories were ascertained  using a dynamic (time-dependent) method, in which individuals were treated as cases only from  their age at diagnosis onwards.  It was observed that diabetic patients are at an increased risk of colorectal cancer, particularly  early-onset colorectal cancer and that the magnitude of this association was similar to that of  having a first-degree relative with colorectal cancer. This risk was further elevated in diabetic  patients with an additional family history of colorectal cancer with nearly 7 times the risk of  colorectal cancer compared to those in the general population with no diabetes and no family  history of colorectal cancer. Building on these findings, the study provided risk-adapted ages of  initial colorectal cancer screening for diabetic patients with and without a family history of  colorectal cancer. It was found that diabetic patients reached the population level of risk several  years earlier irrespective of the benchmark age of screening in the population (age 45, 50, 55 or  60).  The results regarding risk of colorectal cancer in diabetic patients provide clinically-relevant and  evidence-based data designed for real-time counselling of diabetic patients who are at an  increased risk for early-onset colorectal cancer. The findings could help physicians provide  personalized screening recommendation for diabetic patients and at the very least make patients  wary of their increased risk so they can make lifestyle changes accordingly. Overall, irrespective  of the specific application, the findings carry strong potential in impacting the management of  diabetes, especially in young patients who are not targeted by colorectal cancer screening.
date: 2021
type: Dissertation
type: info:eu-repo/semantics/doctoralThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserver/30612/1/AliKhan_Uzair_24_07_1994_Dissertation.pdf
identifier: DOI:10.11588/heidok.00030612
identifier: urn:nbn:de:bsz:16-heidok-306127
identifier:   Ali Khan, Uzair  (2021) Colorectal cancer risk prediction and risk-adapted colorectal cancer screening in patients with diabetes mellitus.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/30612/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng