The number of American women getting mammograms fell in the early part of the 21st century, reversing a trend that helped slash deaths from breast cancer.
The study from the U.S. National Cancer Institute confirms earlier state and regional reports that screening for the most common cancer in women is declining. The drop may help explain why new cases of breast cancer fell in recent years, the researchers said. The phenomenon has been widely attributed to a decrease in the number of older women taking hormones.
In the 2005 survey, 66 percent of women aged 40 and older said they had a mammogram within the last two years. The number peaked in 2000 at 70 percent, a near doubling from 39 percent in 1987. The biggest decline from 2000 to 2005 was in women aged 50 through 64, particularly those with health insurance, regular doctors and the most money, the study found.
The study will appear in the June 15 edition of the American Cancer Society’s journal Cancer. About 180,000 women are diagnosed with breast cancer each year in the U.S., making it the most common malignancy in females, and 40,000 die.
One explanation for declining mammogram rates may be that many women have stopped seeing doctors to get prescriptions for hormone replacement therapy, Breen said. A landmark study released in the summer of 2002 found the pills, used to ease menopause symptoms, also raised risks of heart disease and cancer.
Sales of the drugs plummeted. In 2000, about 62 million women used hormone replacement therapy, mainly Wyeth’s Premarin and Prempro. By 2005, only 18 million women used them, sales data shows. During the same period, breast cancer rates also fell. The timing led many to link the decline in cancer rates to reduced use of hormones, which can fuel cancer growth.