Interesting article. Here is Dr. Susan Love on the subject: "Many women with hormone-sensitive tumors are now taking an aromatase inhibitor as part of their breast cancer treatment. These drugs—anastrozole (brand name Arimidex), letrozole (brand name Femara), and exemestane (brand name Aromasin)—reduce estrogen by blocking the aromatase enzyme and keeping it from converting androgens into estrogen. Clinical trials have found that these drugs, unlike the hormone therapy tamoxifen, increase bone fracture risk. For women who have osteoporosis and are on aromatase inhibitors, bisphosphonates should help reduce fracture risk. For women with osteopenia, though, it still makes more sense to wait until osteopenia has advanced to osteoporosis to begin taking these drugs. The exception would be a woman who is starting on an aromatase inhibitor and is already close to a –2.5 on her DEXA scan. In this case, she may want to start on a bisphosphonate while starting on the aromatase inhibitor." https://drsusanloveresearch.org/prevention-and-treatment-osteopenia/