More than 60 percent of cancer patients are older adults 鈥� and that will rise to 70 percent by 2040. 聽Yet seniors continue to be underrepresented in clinical trials, making it difficult to assess how treatments are likely to help or harm them.
The newest evidence of the problem comes from a Food and Drug Administration analysis, which found that only 40 percent of patients participating in cancer clinical trials were 65 and older. The analysis, which has not yet been published, was presented at the American Society of Clinical Oncology鈥檚 annual meeting in June.
Clinical trials investigate the safety and effectiveness of new drugs and therapies, as well as ways to prevent illness and detect conditions early. Their discoveries help guide medical practice.
Yet, older adults are often not included in research studies to any significant extent. This is especially true for cancer patients in their 70s and 80s, according to the FDA鈥檚 data:
- While 19 percent of breast cancer patients are 75 or older, only 4 percent of breast cancer clinical trial participants are of this age.
- Although 33 percent of colon cancer patients are in the 75-and-up group, a mere 8 percent of patients studied by researchers fell in that age group.
- While 37 percent of lung cancer patients are 75 or older, only 9 percent of people of that age are represented in lung cancer clinical trials.
The sobering conclusion: 鈥淚t鈥檚 difficult to practice evidence-based medicine in an older population because the data isn鈥檛 there,鈥� said Dr. Stuart Lichtman, professor of medicine at Weill Cornell Medical College in New York City and president of the International Society of Geriatric Oncology.
And it鈥檚 not just cancer. Across medical conditions that disproportionately affect seniors, people 65 and older have a poor showing in clinical trials.
鈥淭here鈥檚 often an assumption that drugs only need to be tested in younger people and results can be extrapolated,鈥� said Dr. Consuelo Wilkins, an associate professor of medicine at Vanderbilt University Medical Center who, with colleagues, is overseeing a major grant to help bring more seniors, 聽blacks, Hispanics and other groups into clinical trials. 鈥淏ut we know that how older adults respond to medications and interventions and their risk for adverse events is different based on their physiology.鈥�
Difficulties enrolling older people in research studies extend to Alzheimer鈥檚 disease. With National Institutes of Health research funding now at nearly $1.4 billion a year, 鈥渨e鈥檙e going to be seeing more and more clinical trials, but it鈥檚 already difficult to get enough people to participate,鈥� said Keith Fargo, director of scientific programs at the Alzheimer鈥檚 Association.
Fewer than one-third of people diagnosed with Alzheimer鈥檚 are eligible to join clinical trials, he said.
Researchers often find older adults unsuitable for trials for multiple reasons:聽 Seniors may have multiple illnesses 鈥� diabetes and hypertension, as well as cancer or Alzheimer鈥檚 disease 鈥� that could complicate the study鈥檚 results, or they may be聽taking several medications already that could interact with therapies being examined.
Also, older adults may live alone, and not have someone who can accompany them to the study site for tests and procedures 鈥� a significant concern for Alzheimer鈥檚 trials, which typically require a caregiver to provide input about the patient鈥檚 condition and progress. Or, seniors can鈥檛 get around easily. Or they鈥檙e frail.
Responsibility falls to a large extent on physicians, said Dr. Richard Schilsky, chief medical officer for ASCO, noting 鈥渢hey don鈥檛 ask older adults whether they want to participate or not. It鈥檚 a combination of concern that older patients might be unable to comply with a trial鈥檚 requirements, which are usually quite rigorous, and concern that specified therapies might be too toxic.鈥�
Two years ago, ASCO issued calling for older adults to be included in more clinical trials. But progress has been slow, acknowledged Dr. Hyman Muss, director of geriatric oncology at the Lineberger Comprehensive Cancer Center at the University of North Carolina-Chapel Hill.
鈥淢y view is that every patient I see, if they鈥檙e eligible for a clinical trial I鈥檒l tell them about it,鈥� he said.
Don鈥檛 assume your doctor will be equally forthcoming. 鈥淎bsolutely, you should take the initiative and ask,鈥� Schilsky recommended. And don鈥檛 assume you need to have run out of options before doing so. 鈥淐linical trials aren鈥檛 just for people who have no treatment options left 鈥� that鈥檚 a common misconception,鈥� Schilsky said.
Debbie Earp, 67, joined a trial at the Lineberger this year, after getting a diagnosis of stage 2 breast cancer in early January. Her responsibilities over the four-month study: wearing a Fitbit, tracking how much exercise she was getting on a daily basis, and filling out a questionnaire about how she was feeling each time she got chemotherapy.
Earp said she agreed to participate because 鈥淚鈥檝e always exercised and I felt, from a physical and psychological point of view, anything that was going to motivate me during treatment to exercise more would be a good idea.鈥� The goal of the trial was to examine how physical activity affects older breast cancer patients鈥櫬� response to chemotherapy.
Of course, clinical trials aren鈥檛 for everyone. Some older adults are reluctant to consider them because they鈥檙e skeptical of unproven therapies. Others may choose to focus on their quality of life instead of aggressive treatments.
There are good resources about clinical trials on the internet, if you know where to look. The National Institute on Aging has prepared , including a list of questions that seniors should ask before deciding whether to join a trial. The FDA has a that delves into issues such as informed consent 鈥� making sure you鈥檙e fully informed about the potential benefits and harms of a research study, among other essential information.
For those who want to look for trials on their own, the NIH sponsors , a database of studies across the world, searchable by disease and geography. is an effort to make the NIH site more consumer-friendly, created at Vanderbilt University. is another Vanderbilt effort where people who want to participate in studies can sign up and be matched with clinical trial sponsors. And is a one-stop-shop for clinical trials for people with Alzheimer鈥檚 disease, their caregivers, and people interested in preventing dementia, currently listing more than 250 scientific studies.
Make sure you run whatever prospects you find by your doctor. 鈥淰ery few patients have the expertise to understand if a clinical trial is appropriate for them,鈥� Schilsky said. 鈥淵ou really need an expert opinion to help you understand what you find.鈥�
Update: This story was updated on July 21, 2017 to delete an extraneous word.
KHN鈥檚 coverage related to aging & improving care of older adults is supported by and its coverage of end-of-life and serious illness issues is supported by .
Correction: A previous version of this story misstated the percentage of patients participating in cancer clinical trials who are 65 and older. The correct number is 40 percent.