Risk of Endometrial Cancer in Women with Diabetes: A Population-Based Retrospective Cohort Study

Lina Zabuliene; Augustė Kaceniene; Laura Steponaviciene; Donata Linkeviciute-Ulinskiene; Rimantas Stukas; Rokas Arlauskas; Rasa Vanseviciute-Petkeviciene; Giedre Smailyte

doi:10.3390/jcm10163453

Risk of Endometrial Cancer in Women with Diabetes: A Population-Based Retrospective Cohort Study

J Clin Med. 2021 Aug 4;10(16):3453. doi: 10.3390/jcm10163453.

Authors

Lina Zabuliene¹, Augustė Kaceniene², Laura Steponaviciene³, Donata Linkeviciute-Ulinskiene⁴, Rimantas Stukas⁵, Rokas Arlauskas⁵, Rasa Vanseviciute-Petkeviciene^{3

6}, Giedre Smailyte^{2

5}

Affiliations

¹ Institute of Clinical Medicine, Faculty of Medicine, Vilnius University, Ciurlionio g. 21, 03101 Vilnius, Lithuania.
² Laboratory of Cancer Epidemiology, National Cancer Institute, P. Baublio g. 3b, 08406 Vilnius, Lithuania.
³ Consultative Polyclinic Department, National Cancer Institute, Santariskių Str. 1, 08660 Vilnius, Lithuania.
⁴ Institute of Biomedical Sciences, Department of Pathology, Forensic Medicine and Pharmacology, Faculty of Medicine, Vilnius University, Ciurlionio g. 21, 03101 Vilnius, Lithuania.
⁵ Institute of Health Sciences, Faculty of Medicine, Vilnius University, Ciurlionio g. 21, 03101 Vilnius, Lithuania.
⁶ Clinic of Obstetrics and Gynecology, Faculty of Medicine, Institute of Clinical Medicine, Vilnius University, Ciurlionio g. 21, 03101 Vilnius, Lithuania.

Abstract

The aim of this study was to examine the association between type 2 diabetes (T2DM), use of glucose-lowering medications and endometrial cancer (EC) risk.

Methods: The risk of EC incidence among women with T2DM in Lithuania was assessed using a retrospective cohort study design. Female patients who were registered with T2DM between 1 January 2000 and 31 December 2012 were identified in the National Health Insurance Fund database. EC cases (ICD-10 code C54) were identified from the Lithuanian Cancer Registry. Standardized incidence ratios (SIRs) were calculated by dividing the observed numbers of EC among patients with T2DM by the expected number of EC, calculated using national rates.

Results: A total of 77,708 diabetic women were included in the analysis, and 995 cases of EC were identified. A significantly increased EC risk in diabetic women was found as compared to the general population (SIR = 1.69, 95% CI 1.59-1.80). The greatest EC risk was found among younger patients at T2DM diagnosis, and the risk declined gradually with increasing age but persisted in being significantly increased among all age groups. The risk for EC increased with increasing duration of diabetes, and the highest EC risk was observed more than 10 years after T2DM diagnosis. A significantly higher EC risk than expected from the general population was found in all patient groups by glucose-lowering medication combinations. The lowest EC risk was observed in diabetic women who were users of "oral only" (without metformin) (SIR = 1.42, 95% CI 1.10-1.83) and "metformin only" (SIR = 1.69, 95% CI 1.49-1.92) medications. A two times greater EC risk was observed among the remaining glucose-lowering medication categories. In contrast, use of insulin only was not related to a higher EC incidence risk (SIR = 0.45, 95% CI 0.23-0.86); however, the risk estimation was based on nine cases.

Conclusions: Our study shows a significantly increased EC risk in diabetic women as compared to the general population. In this study, a significantly higher EC risk was found in all patient groups by glucose-lowering medication combinations, except for insulin only users.

Keywords: cancer risk; cohort study; endometrial cancer; glucose-lowering medication; type 2 diabetes mellitus.