Hormone therapy and diabetes – is there a link?

The study investigated the effects of androgen deprivation therapy on diabetes control in men with prostate cancer.

Androgens (male sex hormones such as testosterone) are vital for the survival of the cells of the prostate gland. Therefore in prostate cancer, which is in fact uncontrolled growth and multiplication of prostate cells, elimination of androgens can be beneficial for tumor suppression. This is known as androgen deprivation therapy (ADT). This can be achieved with medication that interferes with androgen production, or by surgically removing the testicles (which are responsible for producing androgens).

However, androgens have many roles in the human body. It has been found that disrupting their activity can cause diabetes by making insulin, the hormone that regulates glucose (blood sugar), less effective.

This study assessed HbA1c levels (a measurement of average blood glucose levels over the past 3 months) and intensification of diabetes drug treatment (adding medications or increasing doses) among 4,474 men with prostate cancer and diabetes. 2,237 men were treated with ADT and 2,237 who were not.

The average HbA1c level in all patients at the beginning of the study was 7.24%. After 1 year, HbA1c levels in the group who received ADT had increased to 7.38% while the level in the group who had not received ADT had decreased to 7.14%. This resulted in a 0.24% difference between the groups. Similar results were found at 2 years.

Treatment with ADT was associated with a 20% increased chance of having diabetes medications added or drug doses increased.

The authors concluded that ADT compromises diabetes control in men.

It is unknown what other treatments were given. It is possible that diabetic control is influenced by other factors and aspects of treatment for prostate cancer, and that patients in these two groups differed not only by ADT treatment status.

If you have diabetes in prostate cancer, it is recommended that you discuss the benefits of ADT as well as the drawbacks in relation to diabetes control before embarking on this therapy.