Benefits and harms clarified with decision aid in women ages 75-plus

Older women who received a decision aid on screening mammography before seeing their primary care physician (PCP) were less likely to choose screening, suggesting that the decision aid may help reduce over-screening, researchers reported.

In a 546-woman (ages ≥75 years) study, 51.8% received the decision aid and, after 18 months, 9.1% (95% CI 1.2% to 16.9%) fewer of those women underwent mammography screening versus those in the control group who received a home safety pamphlet pre-PCP visit (51.3% vs 60.4%, adjusted risk ratio 0.84, 95% CI 0.75 to 0.95, P=0.006), according to Mara A. Schonberg, MD, MPH, of Harvard Medical School and Beth Israel Deaconess Medical Center in Brookline, Massachusetts, and co-authors.

Also, compared with controls, women in the decision aid arm were more likely to rate their screening intentions lower from pre-visit to post-visit, to be more knowledgeable about the benefits and harms of screening, and to have a documented discussion about mammography with their PCP, they wrote in JAMA Internal Medicine.

The authors pointed out that there are “hundreds” of decision aids available, but “few are used, mainly because they are inaccessible, are not current, are too long, require high literacy, have not been rigorously tested, or are not disseminated. Because the DA used herein is effective, implementation should be pursued as a next step.”

Specifically, the authors developed a paper-based decision aid for women ages ≥75 years, based on the Ottawa Decision Support Framework, which asks 10 questions “about their health from a validated mortality index… to calculate a health score; higher scores are associated with shorter life expectancy.”

In an invited commentary, Joann G. Elmore, MD, MPH, of the David Geffen School of Medicine at the University of California Los Angeles, and Q. Ngo-Metzger, MD, MPH, of the Bernard J. Tyson School of Medicine, Kaiser Permanente in Pasadena, California, explained that “Simulation models indicate that in women aged 74 years with average health and life expectancy, screening 1,000 women would result in about 1 breast cancer death prevented (with the number needed to screen to prevent 1 breast cancer death ranging from 1,125 to 1,421 women).”

But screening 1,000 women would result in a high number of false-positive results and the potential for overdiagnosis, which Elmore and Ngo-Metzger described as “an indolent tumor that, if left untreated, would not have caused symptoms or harm during the woman’s lifetime.”

Taking that data into consideration, as well as other issues such comorbidities, “Guidelines for prostate, colorectal, and breast cancer screening are increasingly calling for adjustments when a patient’s life expectancy is less than 10 years. Unfortunately, physicians have a hard time implementing this recommendation,” they noted.

Elmore and Ngo-Metzger acknowledged that telling a patient “You probably won’t live long enough to benefit” from screening may not be the best way to communicate, so “research on decision aids… contributes to an important and beneficial conversation in clinical care and cancer screening.”

The cluster randomized trial (the PCP served as the unit of randomization) study was done at 11 primary care practices (academic and community) in Massachusetts or North Carolina. Among nearly 1,250 eligible women, 546 (ages 75 to 89 years) participated. These women did not have breast cancer or dementia, and had undergone a mammogram within 24 months, but not within 6 months. They saw one of 137 PCPs from November 2014, to January 2017.

A research assistant (RA) administered a pre-visit questionnaire on each participant’s health, breast cancer risk factors, sociodemographic characteristics, and screening intentions. After the visit, the RA administered a post-visit questionnaire on screening intentions and knowledge, the authors explained, adding that all analyses were done on an intent-to-treat basis.

Patients in the two arms were well matched, with a mean age of 79.8 years. More than three-fourths (78.4%) were non-Hispanic white, while 59.1% had completed college. About 35% had a <10-year life expectancy.

The authors noted that “Women who opted out or declined to participate were similar in age to participants but were less educated and in worse health; women who declined were also less likely to be of non-Hispanic white race/ethnicity and to have had a recent mammogram.”

For the secondary outcomes, Schonberg’s group explained that “effect modification was examined by PCP site and patient age, educational level, life expectancy, and breast cancer risk. They reported that women in the DA arm were more likely to rate their screening intentions lower from pre-visit to post-visit (24.5%) versus (15.3%) of the than those in the control arm.

The decision-aid arm also reported that they were more knowledgeable about the benefits and harms of screening (25.5% versus 11.7%), and to have a documented discussion about mammography with their PCP (47.4% versus 38.9%; all percentages adjusted). However, the authors cautioned that they “did not capture the effects of the [decision aid] on visit length,” which was a study limitation.

Finally, women in the decision-aid arm tended to be less likely than participants to undergo diagnostic mammography within 18 months versus controls (4.9% versus 8.7%), and breast cancer diagnoses were rare at five total with three in the decision-aid arm. “No one died of breast cancer during follow-up,” the authors wrote, although 3.9% of those in the decision-aid arm died of other causes within 18 months versus 2.3% of controls.

In terms of patient feedback, 94.9% of the women in the decision-aid arm said they would recommend it, 75.2% said the length of the decision aid was acceptable, while 54.0% said they thought it was well balanced, and 85.2% said reading the decision aid did not cause them any anxiety about their screening options.

“We are surveying PCPs to obtain their feedback on the [decision aid],” the authors stated.

  1. Receipt of a decision aid before a visit with a primary care physician (PCP) led to women (ages ≥75 years) being more knowledgeable about mammography screening, having more discussions with their PCP about screening, and fewer women being screened.

  2. The majority of women in the trial’s decision aim arm said they would recommend it and that reading the decision aid in advance did not cause them any anxiety about their screening options.

Shalmali Pal, Contributing Writer, BreakingMED™

Schonberg reported grants from the National Cancer Institute and a relationship with UpToDate. Co-authors reported grants from the NIH and the National Institute on Aging.

Elmore reported serving as the editor-in-chief of adult primary care topics at UpToDate. Ngo-Metzger reported being the former scientific director of the U.S. Preventive Services Task Force.

Cat ID: 22

Topic ID: 78,22,282,464,494,730,22,691,255,463,925