Older adults' attitudes about continuing cancer screening later in life: a pilot study interviewing residents of two continuing care communities

Although cancer is an important cause of morbidity and mortality in older adults [1], the incidence of other serious conditions also increases with age. These competing causes of mortality decrease the likelihood that an older individual could experience a survival benefit from cancer screening [2] because cancers are relatively slow growing. Therefore, those at advanced age and with multiple co-morbid conditions could undergo screening and not live long enough to realize a mortality benefit [3]. Available evidence from cancer detection trials in middle aged patients suggests that at least 5 years of life expectancy is needed to reduce disease specific mortality for breast and colon cancer [4, 5], and for prostate cancer it is estimated that men should have a life expectancy of 10 or more years [6, 7].

Older adults' life expectancy varies widely depending upon age and health states [3]. To accommodate the wide variation in life expectancy, individualized decision making is recommended for cancer screening decisions later in life [3, 8, 9]. During this process, older adults and their physicians consider the risk of dying from cancer, dying from other causes besides cancer, the risks and benefits of screening, and personal preferences [3].

For individualized decision making to be implemented in clinical practice, older adults need an opportunity to obtain and understand information necessary for informed decision about whether to continue or stop cancer screening [10, 11]. This information involves concepts that may be difficult to understand, such as, competing causes of mortality and delayed benefit from screening. A nurse led program to promote individualized decision making in a continuing care retirement community demonstrated a decrease in screening behaviors over one year; although these results were not statistically significant the number of participants was small [12]. These results suggest that education could promote individualized decision making, but it did not examine attitudes toward the information thought necessary for an informed decision or its relevance to decision making. If older adults do not consider this information relevant to their decision making or would not consider stopping cancer screening, these attitudes could serve as an important barrier to the acceptance of individualized decision making.

Therefore, we undertook this study to better understand the perspectives of older adults in regards to individualized decision making about cancer. Our intent was to assess aspects of cancer screening decisions unique to older adults, including considerations about the possibility of stopping screening. We interviewed older adults to determine 1) if older adults reported the opportunity to engage in individualized decision making with their physicians 2) their attitudes about information important for individualized decision making, and 3) their attitudes about continuing cancer screening later in life.

The 116 participants from the two continuing care retirement communities were well educated, most (83%) had college degrees; 76% were women, and 64% were age 80 and over. All were self-sufficient in basic activities of daily living. The majority reported good to excellent health, although 40% reported having 2 to 4 of the health conditions from Katz's modification of the Charlson co-morbidity measure for interviews [15] (history of cardiovascular disease, congestive heart failure, diabetes, pneumonia, chronic obstructive lung disease or asthma, ulcer disease, renal disease, connective tissue disease, cirrhosis or liver damage, and cancer).

Thirty-nine percent of participants reported having had a previous, not current, diagnosis of cancer other than skin cancer. For those who had been diagnosed with cancer, 6 had colon cancer, 18 had breast cancer, and 13 had prostate cancer. Among those who had not been diagnosed with colon, breast, or prostate cancer, 98% reported having been screened for breast or prostate cancer in the last 5 years, 67% within the past year. Similarly, 96% were screened for colon cancer, 67% within the last year. Participants' age 85 and older had similar screening rates to those under age 85; 91% had been screened for colon cancer within the last 5 years, 52% within the last year and 97% had been screened for breast or prostate cancer, 83% within the last year.

About half of this select group of older adults reported having had an opportunity for individualized decision making with their physicians regarding cancer screening since turning age 70; however, a majority of participants reported that they would like to have these types of discussions with their physicians. Among those who had discussions, only 13% of all participants said they had been asked if they wanted to continue screening. Although many wanted to discuss the possibility of stopping screening with their physicians, about half preferred not to discuss life expectancy and 62% did not think that physicians' estimates of life expectancy were important in making screening decisions. Their positive responses to attitudinal questions suggest that they strongly believe that continued cancer screening is of benefit to them and to others; only a small number had stopped cancer screening completely; most planned to continue screening throughout their life, and only a minority believed that older adults with severe co-morbidities and resultant functional limitations should stop cancer screening. In most cases, those older than 85 with presumably shorter life expectancies, held similar beliefs to those who were younger. Factors important to participants when deciding about stopping include: age, deteriorating or poor health, concerns about the effectiveness of the tests, and doctors' recommendations.

Many studies have examined cancer screening behavior in adults 64 and over [17‐23]. Some studies focused on under-utilization of cancer screening, identifying barriers to screening in older adults in order to promote screening [17, 22, 24]. Recently, the focus has shifted from a health promotion strategy for all older adults to a strategy of individualized decision making for adults age 75 and over [3, 12, 25, 26]. This strategy takes into account the wide variation in health status for this population and acknowledges the lack of direct evidence supporting screening.

Few studies have examined individualized decision making strategies. Some evidence suggest that education about the pros and cons of screening as an older adult could influence screening behavior [12]. Our findings suggest that there may be some important patient barriers to individualized decision making in clinical practice. Although we chose this well educated population as a best case scenario, we were surprised to find that only about half remembered having discussions with their doctors about cancer screening. Furthermore, a minority believed that key pieces of information necessary for informed decision making, such as delayed benefits of cancer screening and the need to consider life expectancy to realize a benefit from screening, were important.

The participants' responses to the question, "What might make you stop cancer screening?" included age, deteriorating health, poor quality of life, or nearing death, concerns about the reliability of the tests, and doctors' recommendation. Resnick asked residents in several continuing care retirement communities the converse of this question, why they had not been screened. She found age, and lack of doctor recommendation as the most common reasons given [27, 28]. She also evaluated predictors of screening test completion in these venues and found that increasing age and the number of chronic conditions were consistently predictors of not getting screening tests [27‐29]. However, physician recommendation was not evaluated in these models and has been shown to be a significant influence on screening behavior [30‐32].

Because physician recommendations are so influential, what role should they play in older adults where direct evidence supporting screening is lacking? Participants in this study were relatively healthy and most would likely benefit from screening. Their physicians may have recommended they have screening without further discussion. However, the importance of individualized decision making has been stressed for patients of all ages because few individuals who undergo screening actually benefit, while all are exposed to the potential risks of false positives and the burden of screening [3, 33]. This burden may fall more heavily on older adults, making participation in decision making more important [34].

However, encouraging individualized decision making and discouraging physician recommendations against screening could result in screening among those least likely to benefit. Forty-three percent of our participants would consider screening even if their doctor recommended against it and the majority wanted to continue to screen throughout their lifetime. Although the right to refuse screening is well supported by ethical tenets, the ethics of continuing screening when the mortality benefit is unlikely is less certain [35]. A key limitation of our study is that it is not clear whether the enthusiasm for screening results from a lack of knowledge about the delay in mortality benefits from screening later in life, or because they value other benefits from screening such as a psychological benefit of alleviating fears of cancer, or would want aggressive treatment for cancers if found [36]. Additional research is needed to determine whether older adults adequately understand this information or use other determinants to make their decisions about cancer screening.

Caution should be used in generalizing our findings to other populations. Participants in our study were volunteers and may have chosen to participate because of a strong belief in cancer screening. Many also had a previous diagnosis of cancer. Consequently, our results may be biased in favor of cancer screening. However, we should point out that our findings are consistent with a nationally representative survey that found a similar enthusiasm for cancer screening [37]. Additionally, our participants were very well educated, reflecting the population of the continuing care retirement communities in our area. In the general population, only 15% of those age 70 and older had graduated from college in 1999 compared to 83% in our population [38]. Finally, although we cognitively tested the questionnaire, the questions we used have not been validated previously. Therefore, we cannot be certain that participants interpreted the questions as we intended.

This study assessed older adults' perspectives on continuing cancer screening and individualized decision making for cancer screening. In this select group of older adults, many reported not having the opportunity to assess the risks, benefits, and uncertainties of cancer screening later in life. However, the majority of participants said that they would prefer to have discussions about the possibility of stopping screening with their physicians. Despite this preference, many participants were reluctant to discuss life expectancy in this context and did not believe that it was important. Participants held positive attitudes about continuing cancer screening later in life, and many may have had unrealistic expectations about the potential survival benefits of screening. Future research is needed to determine whether educating older adults about the importance of longevity in screening decisions would be acceptable, affect older adults' attitudes about screening, or change their screening behavior.