Are older adults with cancer and Alzheimer’s more sensitive to pain?

Researchers at Vanderbilt University Medical Center and The Ohio State University have been awarded a five-year, $5 million grant from the National Institutes of Health and the National Institute on Aging to study the impact of cancer and co-occurring Alzheimer’s disease on pain perception.

“People with worsening cognitive function are at risk of experiencing pain that goes untreated. This may be particularly harmful for older adults with Alzheimer’s who also suffer from chronic cancer pain,” said Ronald Cowan, M.D., a professor in the Department of Psychiatry and Behavioral Sciences and a principal investigator on the grant.

“This funding will help us to further understand and better manage pain in older adults with dementia,” Cowan said.

Recognizing Untreated Pain

“If you asked residents with dementia about their pain, they actually reported increased distress.”

The multi-site study will be co-led by Cowan and collaborator, Todd Monroe, Ph.D., associate professor of nursing at The Ohio State University. The two investigators have been studying pain management in dementia patients for several years and have previously reported that in nursing homes and similar facilities, residents with dementia receive less treatment for their pain compared to residents without a dementia diagnosis.

“If you asked residents with dementia about their pain, they actually reported increased distress,” Cowan explained. “These initial findings – that people with Alzheimer’s were actually feeling more pain, and that people weren’t asking them about it, so they maybe didn’t spontaneously report it – helped launch this new work.” 

Project Scope

The grant will study the response of individuals to experimental pain (thermal and pressure) to determine whether people with chronic cancer pain and comorbid Alzheimer’s disease are at greater risk of suffering from poorly managed pain at end of life.

“If you have pain for a long time, and it’s untreated, you can become increasingly sensitive to the pain, and the pain circuitry, if you will, gets amplified,” Cowan said.

Cowan and Monroe hypothesize that individuals with cancer pain develop central nervous system sensitization and are at risk of experiencing intense pain, and in those individuals with co-occurring Alzheimer’s, brain damage leads to further alterations in central nervous system pain processing. The result is a decreased ability to recognize and self-report pain and an increased risk of undertreatment of cancer pain.

In total, 264 adults aged 65 to 86 will be recruited for the study, balanced by sex and group. The study will include people with stage 4 prostate or breast cancer, those with Alzheimer’s disease and stage 4 prostate or breast cancer, or people with Alzheimer’s disease only.

Improving Care

This will be the first study to test pain threshold and perception in individuals with cancer and comorbid Alzheimer’s, and Cowan hopes the findings will help guide pain care for this vulnerable group.

“We hope that people will begin to more systematically assess and assume that people with dementia do have pain, even if they don’t report it, and that they will begin to treat them more readily,” Cowan said. “This will hopefully help relieve some of the suffering that we think is associated with pain in this group.”

“We hope that people will begin to more systematically assess and assume that people with dementia do have pain, even if they don’t report it.”

About the Expert

Ronald Cowan, M.D.

Ronald Cowan, M.D., Ph.D., is professor in the Departments of Psychiatry and Behavioral Sciences, and Radiology at Vanderbilt University Medical Center. His research focuses on the use of neuroimaging and complementary methods to explore the neurobiology of addiction and its consequences in humans. His clinical interests include psychosomatic medicine, depression, substance use, obesity and LGBTQI mental health.