Researchers examined the prevalence of chronic opioid use among survivors of breast, colorectal and lung cancer.
Cancer survivors and matched controls are more likely to have chronic opioid use as they age — and cancer type also plays a role, according to study findings published in the Journal of Clinical Oncology.
Researchers from Memorial Sloan Kettering Cancer Center (MSK) in New York City and Kaiser Permanente Washington Health Research Institute in Seattle examined opioid usage trends in survivors of female breast (21,829 individuals), colorectal (13,101 individuals) and lung (11,859 individuals) cancer.
They collected data from the SEER registry linked to Medicare of 46,789 survivors who had received a diagnosis of cancer from 2008 to 2013, were 66 years and older and had no prior history of chronic opioid use. Survivors were then matched with a control group of 138,136 people who did not have cancer and had the same Medicare coverage. Chronic opioid use was defined as using for 90 consecutive days and high-dose was defined as an average daily dose of 90 or more morphine milligram equivalents (MME).
“The potential for opioid exposure continues after the completion of cancer treatment because up to 40% of cancer survivors experience pain and may receive opioids for pain management,” the researchers wrote.
The researchers learned that chronic opioid use was highest among older lung cancer survivors compared with survivors of breast and colorectal cancer. Lung cancer survivors were also more likely to have chronic opioid use than the controls for the first five years after initial diagnosis.
The percentage of colorectal cancer survivors with chronic opioid use ranged from 2.7% in the first year to 4% six years after diagnosis. These survivors were more likely to have chronic opioid use for the first two years compared with controls.
Survivors of breast cancer were less likely to have chronic opioid use compared with controls during each year after diagnosis. The rate of chronic opioid use ranged from 1.9% to 3.7% from the first to sixth year.
Compared with matched controls, high-dose chronic opioid use was more common among breast cancer survivors for the first three years, for lung cancer survivors for the first four years and for colorectal cancer survivors for the first five years.
“There are really big differences in chronic opioid use depending on the type of cancer people have. We can’t generalize across all cancer survivors,” lead author Dr. Talya Salz, assistant attending outcomes research scientist at MSK, said in an interview with CURE. “Another important takeaway is that chronic opioid use is more common for lung and colorectal cancer survivors compared with their counterparts in the early years after diagnosis. But, by a few years out, this is no more common than it is among cancer-free people in the population. That should be reassuring as we use opioids to control pain in patients and survivors that there is limited evidence of long-term risk.”
However, this study was limited to only older cancer survivors and three types of cancer. It’s important to study this in other cancers, such as head and neck where chronic pain is prevalent, and in younger survivor populations, Salz explained.
Health care professionals receive guidance on opioids to manage pain for patients, those at end-of-life and the general population, but they do not exist for cancer survivors, Salz said. “The real question: Is this ignored population of cancer survivors who may not have any evidence of disease, are they particularly at risk?” she said. “From this study, we are not seeing evidence that there is a real increased risk of long-term harms in this older population. This is a small piece of the puzzle for the opioid crisis, but I think it’s a very large and important population that we need to explore more.”