Chronic Pain Increases the Risk of Dementia

People experiencing chronic pain at multiple body locations are at higher risk of dementia and faster cognitive decline, a new study finds.

About 50 million United States adults suffer from chronic pain. It can limit their quality of life and may be difficult to manage, depending on the issue. Chronic pain has many causes, including autoimmune diseases, chronic conditions, and past injuries.

Nearly half of chronic pain patients experience multisite chronic pain (MCP), defined as pain at multiple anatomical locations. Researchers at the Institute of Psychology at the Chinese Academy of Sciences analyzed longitudinal data of 354,943 people from the United Kingdom biobank to learn more about its impact on cognitive functioning.

The study, published in the Proceedings of the National Academy of Sciences, discovered that chronic pain patients with MPC are at greater risk of dementia than pain-free individuals and those experiencing chronic pain at a single site (SCP).

In addition, people with chronic pain in multiple body parts experience broader and faster cognitive decline, including memory, executive function, learning, and attention.

According to the researchers, the risk of neurocognitive abnormality increases with each additional pain site and is mediated by atrophy in the hippocampus, the part of the brain responsible for memory, the volume of which decreases with age.

The study authors equate the effects of multisite chronic pain to the effect of aging in healthy people with an average age of 60.

"Multisite chronic pain may lead to up to eight years of accelerated hippocampal aging, an effect that may underlie a series of cognitive burdens," says Yiheng Tu, corresponding author of the study.

Dementia is a broad term for the decline of brain functioning, such as loss of memory, language, problem-solving, and other thinking abilities, severe enough to interfere with daily life. While dementia primarily affects older individuals, it is not a part of normal aging.

The known risk factors for dementia include:

• Age 65 years and older
• Having parents or siblings with dementia
• Being Black or Hispanic
• Having high blood pressure and high cholesterol
• Smoking
• Experiencing a traumatic brain injury