Can Oral Diabetes Therapies Reduce Cancer Risk?

Patients with type 2 diabetes mellitus (T2DM) are at a greater risk of cancer development, recurrence, and death than the general population, and it appears that both modifiable and non-modifiable risk factors may jointly increase cancer risk.

Researchers from the Cleveland Clinic recently published a retrospective analysis of this association between cancer and diabetes, specifically examining oral diabetes therapies’ potential to mitigate the relationship.

By cross-indexing the Cleveland Clinic’s 25,613-patient Diabetes Registry with the histology-based Tumor Registry of 48,051 cancer occurrences from 1998 to 2006, the authors applied propensity scores to model the time-to-development of incident cancer. In total, the data created 51,994 follow-up person years and identified 892 incident cancer cases.

The researchers found that patients with T2DM were more than 30% more likely to develop cancer than their counterparts who did not have T2DM. According to the authors, the most common cancers recorded in the T2DM population mirrored common cancers in the general population, but at increased incidence rates.

Nevertheless, women who took thiazolidinediones had a 32% decreased cancer risk compared to those who took sulfonylureas. Comparing insulin secretagogues like sulfonylurea and meglitinide to insulin sensitizers like biguanide and thiazolidinedione, the researchers discovered that women who took insulin sensitizers had a 21% decreased cancer risk.

However, no reduction in cancer risk was noted in men, and even after adjusting for a number of other factors, cancer incidence remained elevated.

The researchers concluded that mitigating insulin resistance with sensitizers more effectively reduces cancer risk in women with T2DM than augmenting endogenous insulin levels with secretagogues.