Ninety percent of patients with cancer may experience chemotherapy-induced peripheral neuropathy (CIPN) during treatment, and many will see this adverse effect long after treatment ends.
According to a study published in the Journal of Clinical Oncology, CIPN can affect physical function and quality of life (QOL), and increase the risk of falls, especially in older survivors.1 Researchers from Oregon Health & Science University (OHSU) in Portland examined 512 female cancer survivors—the majority had breast cancer—with an average age of 62. Nearly half (47%) reported symptoms of CIPN, on average, 6 years after treatment.
“I was somewhat surprised by the proportion of women who still reported neuropathy symptoms so far after finishing treatment, although, on the other hand, we have been observing this in our exercise trials for a number of years already,” said Kerri M. Winters-Stone, PhD, research professor, School of Nursing at OHSU, and lead author on the study. “That was what drove us to look at these data in the first place.”
Researchers relied on self-reporting from women with and without symptoms of CIPN on the following: maximal leg strength, timed chair stand, physical function battery, gait characteristics (speed; step number, rate, and length; base of support), self-reported physical function and disability, and falls in the past year. They were asked if they experienced numbness, tingling, or discomfort in their feet in the past week and were then categorized into one of 2 groups: symptomatic (CIPN-positive) or asymptomatic (CIPN-negative). Those women reporting symptoms were asked if they started during or after chemotherapy. A 4-point scale was used to report severity: 1 = a little bit, 2 = somewhat, 3 = quite a bit, 4 = very much. The main purpose was to identify targets for functional rehabilitation.
Compared with CIPN-negative survivors, CIPN-positive survivors had significantly worse self-report, except for maximal leg strength and base of support during a usual walk. Gait was slower among CIPN-positive, with those women taking significantly more, although slower and shorter, steps than did CIPN-negative patients. CIPN-positive patients reported significantly more disability and 1.8 times the risk of falls compared with their negative counterparts. Increasing symptom severity was linearly associated with worsening function, increasing disability, and higher fall risk (all P <.05). CIPN-positive survivors were signiﬁcantly more likely than CIPN-negative to be closer to their cancer diagnosis, to have been diagnosed with stage II or III cancer, to have been treated for a cancer other than breast cancer, to be obese, to be less physically active, and to have worse comorbidities.
“Women came into our exercise programs so deconditioned, and with so many lingering problems, from treatment that remained unaddressed for years,” Winters-Stone said. “We basically had to act like physical therapists, rather than exercise trainers, because we couldn’t even get women to perform basic exercises correctly due to their physical limitations, like neuropathy, pain, and weakness. CIPN is very limiting on mobility and people also change where and how they move in their environment such that, over time, they are less and less independent for daily functioning.”
Limitations to the study included cross-sectional, self-report, and post-treatment. However, Winters-Stone said that asking patients about their neuropathy symptoms and considering early intervention seems to only offer advantages in terms of preserving patient QOL during and after treatment.
“Too often I’ve heard that patients were ‘never told’ about a symptom or side effect or that they were told things would ‘go away after treatment,’ and that makes them frustrated and angry,” said Winters-Stone. “I worry that this happens because providers think they don’t have solutions to offer patients, but exercise can help manage so many treatment-related problems if prescribed properly and, ideally, under the supervision of a trained exercise specialist who has experience and education working in the oncology setting.”