Lower Rates of Hormone Therapy Contributing to Decrease in Mammograms

August 23, 2011

A study published online in the American Cancer Society journal Cancer suggests that when women stop going to their doctors for hormone therapy prescriptions, the physicians do not remind them to get a mammogram.

A study published online in the American Cancer Society journal Cancer suggests that when women stop going to their doctors for hormone therapy prescriptions, the physicians do not remind them to get a mammogram (DOI: 10.1002/cncr.26218). The analysis found that there has been a decline in hormone therapy in women between age 50 and 64 that is linked with a lower mammogram rate in this age group.

The research was stimulated by the observation that national mammography rates dropped for the first time in 2005, but had been rising steadily in the United States from 1987 to 2002. In recent years there has been a decrease in hormone therapy usage because of a reported increased risk of breast cancer; the authors examined whether the drop in hormone therapy usage was linked to the concurrent drop in mammograms.

Previous studies suggested that medical encounters are the best predictor of a woman receiving a mammogram, other correlators are location of practice (community or academic), and HMO coverage.

Nancy Breen, PhD, an economist at the Health Services and Economics Branch of the National Cancer Institute and colleagues used multivariate logistic regression to test for an interaction between hormone therapy use and mammography rates. The authors used data from the 2000 and 2005 National Health Interview Surveys (NHIS). In 2000 a total of 7,125 women were interviewed, and in 2005 there were 7,387 women interviewed. All of the women were over the age of 50. The NHIS is a main source of health information on the non-institutionalized, household population of the United States and is the largest population-based national sample on mammography use.

The results of the analysis found that women were more likely to report a recent mammogram if they also reported more education, a usual source of care, being of any race except non-Hispanic Asian, talking with an obstetrician/gynecologist or other physician in the past 12 months, or if they were currently taking hormone therapy. Women aged 50 to 64 were also more likely to report a recent mammogram if they had private health insurance, and women aged 65 years and older were more likely to report a recent mammogram if they had Medicare Part B or other supplemental Medicare insurance. Variables from the NHIS were associated with 70% to 80% of the change in mammography for the women studied. 

“We analyzed women 65 and older as a single group; however we also examined whether mammography varied within this age group. We found that women 65-74 were more likely to report a mammogram (72%) than women 75 and older (61%). Women 65 and older were more likely to report a recent mammogram if they were taking hormone therapy, had visited or spoken to a doctor recently, reported excellent or very good health, had health insurance coverage beyond 'Part B' (Medicare insurance coverage for hospitalizations only), reported a usual source of care, or had more than high school graduation,” said Dr. Breen.

Overall, the change in hormone therapy use was associated with lower rates of mammography in women aged 50 to 64, but not for women over 65 years of age. This is the first study that has shown a difference in rates by age group. 

“Our research corroborates that a doctor’s recommendation is an important step in getting a mammogram and it shows that when circumstances change, such as evidence about hormone therapy, it can upset the balance and lead to unanticipated and undesirable changes in mammography use,” said Dr. Breen. “In short, we need to continue to ensure that women know about mammography and where they can get it. Mammography also needs to be affordable and convenient for women.” Dr. Breen added that mammography is the best way to detect breast cancer early, when treatment is most effective.

In general, Dr. Breen would like women to be aware of three things: “First, the new ACA prohibits co-payments for preventive services, including screening mammography. So women with insurance, whether private, Medicare, or Medicaid, should not be charged a co-payment for mammography. Second, for those without health insurance or with high-deductable insurance, there are programs (co-sponsored by fed and states) that provide low-cost mammography and, if cancer is detected, most states cover treatment costs too. Third, for women with health insurance coverage, informed consumers should know that most research agrees that early detection of breast cancer with mammography and timely follow up with treatment yields a mortality benefit for women 50-65. Debates in the scientific literature largely have to do with details-at what age women should start and stop and how frequently women need mammograms.”

Lastly, Dr. Breen has a suggestion: “Something medical practices and physicians could do that would really help women get timely mammograms is to use reminder systems. Strong and consistent findings show that reminder systems-whether they remind doctors, women, or both; whether they use mail, phone, or computers-really help women obtain regular timely mammograms. Or at a minimum, allow women to make their next mammography appointment as they are leaving."