Of all the cancer screening methods in this world, was there ever a more controversial procedure than the mammogram? Hundreds of thousands of dollars have been poured into determining when is the ideal time to start this hunt for breast cancer--the US Preventative Services Task Force now says age 50, while the American Cancer Society and other physician groups argue to keep it at 40—but there's a lot of hand-waving over when to stop looking.

At some age, the burdens can outweigh the benefits. A screening mammogram that uncovers a suspicious looking mass may lead to invasive follow-up tests, complications from those tests, surgery and a significant decrease in overall quality of life. That's why most physicians generally stop screening for breast cancer at around age 75.

But for elderly patients who are also cognitively impaired, that age limit might come even sooner.

In a recent study of over two-thousand elderly women, researchers at the University of California, San Francisco found that a significant percent of cognitively impaired women received screening mammograms well into their 70's (18-percent, compared to 45-percent in non-cognitively impaired women).

The procedure—different from mammograms that follow-up on suspicious lumps felt on breast exams—instead scours for harbingers in otherwise healthy women. For the test to be of any benefit, its user must have a life expectancy of at least four to five years. (Otherwise, chances are you'd die from something else before you died from a newly discovered breast cancer, or so the thought goes.)

Severely impaired women in the study had, on average, a life expectancy of only 3.3 years. This means that for the almost 120,000 U.S. elderly women with severe cognitive impairment who underwent screening in 2002, mammograms likely did more harm than good.

Another interesting finding was that having money put you at further risk for potentially unnecessary screening. Elderly impaired women who were married or who had a net-worth of $100,000 or more were almost three-times as likely to receive screening (47-percent versus 18-percent).

All of this data, researchers say, is not meant to create an upper limit age cut-off for screening mammography. Every elderly woman should weigh the risks and benefits for herself and have an informed discussion with her health care provider.

The authors do, however, call for more explicit guidelines against screening for severe cognitively impaired elderly women.

“Screening an active, healthy, independent 75 year old woman who is likely to live for another 15 or 20 years is one thing, but severely cognitively impaired older women with limited life expectancies have immediate health challenges that must take priority.” says lead researcher Louise C. Walter, MD.

READ MORE:
1. http://ajph.aphapublications.org/cgi/reprint/AJPH.2008.158485v1
2. http://news.ucsf.edu/releases/cognitively-impaired-elderly-women-get-unneeded-screening-mammography-study/