Issue 144 Item 2 HRT Shown to Reduce Diabetes Rate in Some Women

HRT can reduce diabetes by 35% in women with heart disease. A study published in the January 6, 2003, issue of the Annals of Internal Medicine, of more than 2,000 women has shown that hormone replacement therapy (HRT) can reduce diabetes by 35% in women with heart disease.

The data were the result of further analysis of the Heart and Estrogen/Progestin Replacement Study (HERS) by researchers at the University of California, San Francisco (UCSF, USA), to determine the effects of HRT compared with placebo in older postmenopausal women with heart disease. Some of the women had existing diabetes and some began the trial with impaired fasting glucose (IFG). Equal proportions of women with diabetes, with IFG, and without diabetes were randomly assigned to HRT or placebo in the trial.

The authors do not recommend the use of hormones for disease prevention, but instead encourage further study of the effects of estrogen and progestin hormone therapy on metabolic complications.

The potential benefit to patients for one health outcome needs to be weighed against the risk for others, such as coronary events and breast cancer, said Alka Kanaya, M.D., principal investigator and a UCSF assistant professor of medicine. But our data allude to important metabolic benefits of HRT that should be studied further.

As Dr. Kanaya has stated, the patients needs have to be weighed against the risks. As you can see in another study published in Feb.BMJ, which showed that HRT use may increase mortality risk in diabetics.

In women with diabetes, HRT is associated with an increased risk of death from ischemic heart disease and from all causes.

The current findings are in agreement with previous reports showing that HRT does not protect against ischemic heart disease. However, the current report expands on past findings by showing that such therapy may actually increase the risk of adverse cardiac outcomes in diabetic women.

The results are based on a study of nearly 20,000 female nurses, at least 45 years of age, who were surveyed about their lifestyle, including HRT use, in 1993. The women were followed until the end of 1998 to determine all cases of death and incident cases of ischemic heart disease and myocardial infarction.

Compared with subjects who never used HRT, current users smoked more, consumed more alcohol, perceived their health to be poorer, were slimmer, and were less likely to be diabetic, the authors note.

No significant differences in risk of ischemic heart disease or myocardial infarction were seen between HRT users and those who never used HRT, the researchers state.

However, among women with diabetes, current HRT use was tied to a 3.2-, 4.2-, and 9.2-fold increased risk of death, ischemic heart disease, and myocardial infarction, respectively, compared with nondiabetics who never used HRT.

Although the reason why HRT may have harmful effects in diabetic women is unclear, "estrogen seems not to improve endothelium dependent vasodilation in women with type 2 diabetes despite its favorable influence on lipoprotein concentrations," the authors note. BMJ 2003;326:426-428.