Vishal Patel, BS, a student at the Dell Medical School at The University of Texas at Austin, and colleagues identified 51,258 cancer survivors from the National Health Interview Survey, representing a weighted population of approximately 178.8 million from 1999 to 2018.
Most survivors were women (60.2%) and were at least 65 years old (55.4%). In 1999, 3.6 million weighted survivors reported functional limitation. In 2018, the number increased to 8.2 million, a 2.25-fold increase.
The number of survivors who reported no limitations also increased, but not by as much. That group grew 1.34-fold during the study period.
For context, “the 70% prevalence of functional limitation among survivors in 2018 is nearly twice that of the general population,” the authors wrote.
Patients surveyed on function
Functional limitation was defined as “self-reported difficulty performing any of 12 routine physical or social activities without assistance.” Examples of the activities included difficulty sitting for more than 2 hours, difficulty participating in social activities or difficulty pushing or pulling an object the size of a living room chair.
Over the 2 decades analyzed, the adjusted prevalence of functional limitation was highest among survivors of pancreatic cancer (80.3%) and lung cancer (76.5%). Prevalence was lowest for survivors of melanoma (62.2%), breast (61.8%) and prostate (59.5%) cancers.
Not just a result of living longer
Mr. Patel told this publication that one assumption people might make when they read these results is that people are just living longer with cancer and losing functional ability accordingly.
“But, in fact, we found that the youngest [– those less than 65 years–] actually contributed to this trend more than the oldest people, which means it’s not just [happening], because people are getting older,” he said.
Hispanic and Black individuals had disproportionately higher increases in functional limitation; percentage point increases over the 2 decades were 19.5 for Black people, 25.1 for Hispanic people and 12.5 for White people. There may be a couple of reasons for that, Mr. Patel noted.
Those who are Black or Hispanic tend to have less access to cancer survivorship care for reasons including insurance status and historic health care inequities, he noted.
“The other potential reason is that they have had less access to cancer care historically. And if, 20 years ago Black and Hispanic individuals didn’t have access to some chemotherapies, and now they do, maybe it’s the increased access to care that’s causing these functional limitations. Because chemotherapy can sometimes be very toxic. It may be sort of a catch-up toxicity,” he said.
Quality of life beyond survivorship
Mr. Patel said the results seem to call for building on improved survival rates by tracking and improving function.
“It’s good to celebrate that there are more survivors. But now that we can keep people alive longer, maybe we can shift gears to improving their quality of life,” he said.
The more-than-doubling of functional limitations over 2 decades “is a very sobering trend,” he noted, while pointing out that the functional limitations applied to 8 million people in the United States – people whose needs are not being met.
There’s no sign of the trend stopping, he continued. “We saw no downward trend, only an upward trend.”
Increasingly, including functionality as an endpoint in cancer trials, in addition to improvements in mortality, is one place to start, he added.
“Our findings suggest an urgent need for care teams to understand and address function, for researchers to evaluate function as a core outcome in trials, and for health systems and policy makers to reimagine survivorship care, recognizing the burden of cancer and its treatment on physical, psychosocial, and cognitive function,” the authors wrote in their paper. Limitations of the study include the potential for recall bias, lack of cancer staging or treatment information, and the subjective perception of function.
A coauthor reported personal fees from Astellas, AstraZeneca, AAA, Blue Earth, Janssen, Lantheus, Myovant, Myriad Genetics, Novartis, Telix, and Sanofi, as well as grants from Pfizer and Bayer during the conduct of the study. No other disclosures were reported.