December 9th, 2010
Meta-Analysis Finds Aromatase Inhibitors Increase Risk for Heart Disease
A new meta-analysis has found that postmenopausal women taking aromatase inhibitors (AIs) instead of tamoxifen to treat breast cancer appear to be at increased risk for cardiovascular complications. The results were presented at the San Antonio Breast Cancer Symposium.
Previous studies suggested that women taking AIs were more likely to develop cardiovascular disease, while women taking tamoxifen were found to be at increased risk for endometrial cancer and venous thromboembolism. In 2008, the FDA warned about an increased risk for heart disease with one AI, anastrozole.
In the new analysis of data from 7 large randomized trials comparing AIs to tamoxifen, the researchers found a similar effect with all AIs. Any exposure to AIs was associated with a 20% increase in the risk for cardiovascular disease (p=0.01; NNT 143) and a 48% increase in the risk for bone fractures (p<0.00001; NNT 34). By contrast, AIs reduced the risk for venous thrombosis (OR 0.53, p<0.00001; NNT 67) and endometrial carcinoma (OR 0.32, p<0.00001; NNT 200).