Using data from a group of Danish nurses, researchers examined the association between hormone replacement therapy and ischaemic heart disease, heart attack, and total number of deaths among 13,084 postmenopausal women.
They found that hormone replacement therapy did not protect women against heart disease or heart attack, but there was a significantly increased risk of death from all causes and ischaemic heart disease among women with diabetes.
This effect was not influenced by other risk factors for heart disease, such as smoking, alcohol consumption, and body mass index, say the authors.
Reasons for the harmful effect of hormone replacement therapy among women with diabetes are inconclusive, but could be explained by an influence on blood sugar control, they conclude.