MedWire News: Breast cancer survivors who take drugs called aromatase inhibitors to prevent their disease recurring do not face an increased risk of cardiovascular problems, researchers have found.
The results may provide reassurance for women taking such drugs, said lead researcher Dr Alain Monnier, from the Centre Hospitalier de Belfort-Montbéliard in France.
Aromatase inhibitors help prevent breast cancer recurrence by reducing blood levels of the hormone oestrogen, which many tumours need to grow.
Several studies have indicated that aromatase inhibitors may be more effective than tamoxifen for preventing the recurrence of such tumours, but concerns have been raised about their effects on cardiovascular health, said Dr Monnier.
To investigate, Dr Monnier and team analysed the results of six studies that compared the cardiovascular effects of aromatase inhibitors with those of tamoxifen and dummy medications.
Results from one of the studies, which investigated the use of aromatase inhibitors in healthy postmenopausal women who had never had breast cancer, revealed no significant difference in cholesterol levels between women taking aromatase inhibitors and those taking the dummy medication.
Another study revealed a transient decrease in cholesterol levels among patients taking aromatase inhibitors compared with those taking a dummy drug.
Studies that compared aromatase inhibitors with tamoxifen revealed slightly higher cholesterol levels among women taking the former drugs. However, Dr Monnier explained that these results were probably due to the fact that tamoxifen has cholesterol-lowering properties, and that aromatase inhibitors did not increase cholesterol levels in real terms.
The team also found that the frequency of heart attacks among women taking aromatase inhibitors was comparable to that in women of the same age who were not taking these drugs.
"This suggests that aromatase inhibitors do not increase the incidence of fatal cardiovascular complications, but lack the cardioprotective effects of tamoxifen," said Dr Monnier.
He concluded: "These findings are important and very reassuring about the safety of aromatase inhibitors."
The research was presented at the European Breast Cancer Conference in Berlin, Germany.