The impact of surgery and oncological treatment on risk of type 2 diabetes onset in patients with colorectal cancer: nationwide cohort study in Denmark
Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark; Department of Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark; Department of Surgical Gastroenterology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
Susanne Boel Graversen
Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark
Jesper Frank Christensen
Centre for Physical Activity Research, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark; Department of Sports Science and Clinical Biomechanics, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark; Digestive Disease Center, Bispebjerg Hospital, Copenhagen, Denmark
Background: Comorbidity with type 2 diabetes (T2D) results in worsening of cancer-specific and overall prognosis in colorectal cancer (CRC) patients. The treatment of CRC per se may be diabetogenic. We assessed the impact of different types of surgical cancer resections and oncological treatment on risk of T2D development in CRC patients. Methods: We developed a population-based cohort study including all Danish CRC patients, who had undergone CRC surgery between 2001 and 2018. Using nationwide register data, we identified and followed patients from date of surgery and until new onset of T2D, death, or end of follow-up. Results: In total, 46,373 CRC patients were included and divided into six groups according to type of surgical resection: 10,566 Right-No-Chemo (23%), 4645 Right-Chemo (10%), 10,151 Left-No-Chemo (22%), 5257 Left-Chemo (11%), 9618 Rectal-No-Chemo (21%), and 6136 Rectal-Chemo (13%). During 245,466 person-years of follow-up, 2556 patients developed T2D. The incidence rate (IR) of T2D was highest in the Left-Chemo group 11.3 (95% CI: 10.4–12.2) per 1000 person-years and lowest in the Rectal-No-Chemo group 9.6 (95% CI: 8.8–10.4). Between-group unadjusted hazard ratio (HR) of developing T2D was similar and non-significant. In the adjusted analysis, Rectal-No-Chemo was associated with lower T2D risk (HR 0.86 [95% CI 0.75–0.98]) compared to Right-No-Chemo. Conclusions: This study suggests that postoperative T2D screening should be prioritised in CRC survivors with overweight/obesity regardless of type of CRC treatment applied. Funding: The Novo Nordisk Foundation (NNF17SA0031406); TrygFonden (101390; 20045; 125132).
