Type 2 diabetes and breast cancer are two health conditions that share some of the same risk factors and pathways including obesity, changes in insulin-like growth factors, steroid hormone changes, and changes in inflammatory chemicals produced by fat cells. In fact some research studies suggest that type 2 diabetes is linked to a 20-30% increased risk for developing breast cancer.
The impact of type 2 diabetes on breast cancer outcomes is of particular interest because it has been reported that about 15-20% of breast cancer patients have type 2 diabetes, while more likely go undiagnosed. A new breast cancer research study used data collected from 3,003 women with a history of early stage breast cancer who took part in a larger breast cancer study. For this new study, glycated hemoglobin (HbA1c) levels were used to determine diabetes status with levels between 6.5-6.9% indicating high risk for diabetes and levels of 7.0% and above indicating type 2 diabetes. Analysis of the relationships between type 2 diabetes and breast cancer outcomes in this population of women with a history of breast cancer showed that
Hb1Ac levels higher than 6.5% (high risk for type 2 diabetes) were associated with obesity and more advanced breast cancer upon diagnosis.
Women with type 2 diabetes were about 2.4 times more likely to die from any cause.
Breast cancer-free survival was reduced with increasing levels of Hb1Ac