Friday, July 13, 2001

Chemotherapy Causes Rapid Bone Loss in Women: Study

WASHINGTON (Reuters) - Chemotherapy given to women with breast cancer causes their bone density to decline at a faster rate than previously known, increasing the risk of osteoporosis, researchers said on Thursday.

- 2001/07/13

By Christopher Doering Scientists led by Dr. Charles Shapiro at Ohio State University said they were surprised to find that 35 pre- menopausal women treated with chemotherapy experienced up to an 8% loss in bone density after 12 months of treatment. The median age of the women was 42. The bone loss in the patients treated with chemotherapy was so significant, the researchers said, that the study was halted to allow the women to seek care from their primary physician. ``We were surprised that (bone loss) occurred so early because other studies had begun to evaluate patients at 12 months'' after chemotherapy commenced, Shapiro told Reuters. ``An independent committee met, and they concluded that these 35 women have lost so much bone, 8%, in the spine that it was unethical in view of that to treat them with placebo,'' he said. The study appears in the Journal of Clinical Oncology. Chemotherapy causes a woman's ovaries to shut down prematurely, stopping the production of the female hormone estrogen. The vital hormone is used by the body for reproduction, but it also protects bones from deteriorating. Women naturally stop producing estrogen when menopause begins, but the decline in the hormone, and resulting drop in bone density, occurs at a faster rate when chemotherapy is administered. Post-menopausal women average a decline of about 1% to 2% in bone mineral density per year. The sample size included 49 patients suffering from breast cancer, with 35 entering into early menopause after one year of the chemotherapy treatment. Researchers had later planned to randomly divide seven patients to test the effects of a nasal spray on slowing bone loss--four would receive the spray and three a placebo, or dummy medication. Researchers cautioned that women who experience rapid bone loss are prone to osteoporosis, a disease that causes bones in the hip, spine and wrist to become fragile and break. ``We focus on the side-effects of chemotherapy, but we don't focus as much as we should ... on early menopause leading to rapid bone loss,'' Shapiro said. ``The results of this study support a role for bone density scans in those women who develop chemotherapy induced ovarian failure,'' he added. Osteoporosis can be slowed with a balanced diet rich in calcium and vitamin D, exercise and tests to measure bone density, according to experts.

SOURCE: