Study results indicate that women who have survived breast cancer are more apt to develop diabetes after menopause than women who did not suffer from a bout of breast cancer. These study results were published in the Diabetologia, The Journal of European Association for the Study of Diabetes (EASD). The study was headed by Dr. Lorraine Lipscombe, Women’s College Hospital, Women’s College Research Institute, Toronto, Ontario, Canada.
There have been many published reports where results show a connection between diabetes and cancer, cancer of any form. In particular, though, there is an estimated 20 percent higher risk of diabetes for women after menopause in those who survived breast cancer.
With better treatment for breast cancer, the survival rate has risen. With this higher survival rate, there is a clear need for a better understanding of the long-term health of the survivors as they get older. But, as of this date, there have been few studies that look at the risk of breast cancer survivors and their risk of developing diabetes after menopause.
Dr. Lipscombe, along with colleagues, ran a population-based study which compared the incidence of diabetes among women 55 years of age or older with breast cancer for the period from 1996 to 2008 and compared this population-based study to age-matched women who had not suffered from breast cancer. Dr. Lipscombe and her team also studied the relationship based or whether or not the patient had undergone chemotherapy.
The study results indicated that of 24,976 breast cancer survivors and 124,880 without breast cancer, 9.7 percent developed diabetes. This was through a follow-up period of 5.8 years.
After two years, the risk of developing diabetes among the breast cancer survivors compared to the women without breast cancer began to increase two years after diagnosis. The diagnosis of diabetes in the post-menopausal women increased from 7 percent at the two-year mark to a 21 percent increase at the 10-year mark. For those patients who had received chemotherapy in the treatment of the breast cancer (4,404), the risk was highest in the first two years after diagnosis (24 percent), yet then decreased to an 8 percent increase after 10 years. Also, women who undergo chemotherapy treatments tend to be more closely screened by their physicians for any condition on a follow-up basis that continues for an extended number of years and would receive a diagnosis of diabetes at an earlier stage than those who did not undergo chemotherapy treatments.
Dr. Lipscombe advised: “It is possible that chemotherapy treatment may bring out diabetes earlier in susceptible women. Increased weight gain has been noted in the setting for adjuvant chemotherapy for breast cancer, which may be a factor in the increased risk of diabetes in women receiving treatment. Oestrogen suppression as a result of chemotherapy may also promote diabetes; however, this may have been less of a factor in this study where most women were already post-menopausal.”
Another interesting factor noted in the study was that the use of anti-nausea medication while a patient is undergoing chemotherapy may play a part in the eventual diagnosis of diabetes in breast cancer survivors after menopause. Anti-nausea medications are known to increase blood sugar levels (acute hyperglycemia). However, this effect tends to wear off as time passes.
The results of the study indicate that there is a need for continued comparison studies in the connection between breast cancer survivors and the diagnosis of diabetes, as well as close monitoring of breast cancer survivors for diabetes
