Oral glucose lowering agents and cancer in type 2 diabetes mellitus: focus on sulphonylurea derivatives

Type 2 diabetes (T2D) and cancer are diseases that affect many people worldwide. Cancer is more common in people with T2D. The exact mechanisms of the increased cancer incidence in T2D patients are partly known. An explanation can be that there is an overlap in the risk factors for both. An example of this is obesity. It is also possible that diabetes medication influences the incidence of cancer in T2D. Or it could be explained by the fact that the statistical analysis of the study does not take proper account of factors that could distort the result.
The aim of this thesis was to investigate possible explanations for the relationship between T2D and cancer, including the possible effect of sulfonylureas (SU), a group of glucose-lowering drugs used by hundreds of thousands of Dutch people. Gliclazide, one of the SUs, is the first choice in the treatment of type 2 diabetes as soon as metformin alone does not sufficiently help. In a literature review, gliclazide use appears to be associated with a somewhat lower cancer risk than other drugs from the same group. Contrary to what is often claimed, the various SUs in this group were not associated with weight gain. This dissertation shows that there is a clear relationship between body weight in T2D patients and a large range of common types of cancer in T2D patients. This dissertation also gives cause to assume that women with T2D partially lose their protective effect to develop cancer compared to men. This shows how important it is to conduct gender-specific research and to make gender-specific risk analyses in the day-to-day practice in patient care.