Summary: New findings suggest that poorly treated chronic pain may raise the risk of dementia or Alzheimer’s in older adults. Chronic pain seems to raise the level of certain brain chemicals. That switches on the brain’s immune cells (microglia) and inflames the brain. People with chronic pain may have more beta-amyloid and tau proteins in the fluid around the brain and spine.
One new study shows that chronic pain can raise dementia risk. It may do so in several ways. New evidence suggests that older adults with poorly treated chronic pain are more likely to develop dementia.
To see how two such different conditions might be linked, you need to understand both of them better.
Unlike short-term pain, chronic pain can last long after the illness that started it. It can even happen for no clear reason. It can also come from things not usually thought to cause long-lasting pain, like mood and emotional problems.
Dementia is also a complex disorder with many sides. It can have many causes, from toxins around us to genes, inflammation, a confused immune system and more.
Of course, chronic pain is unlikely to be the prime cause of dementia, but it may be one of the factors. It may increase dementia risk, trigger dementia, or make dementia worse. At least, this is what one of the new studies suggests.
How does chronic pain raise dementia risk?
Chronic pain may raise dementia risk in several ways, and it harms brain health. The new study, published in the Annals of Neurology, looked at data from 995 dementia patients. Most had Alzheimer’s. Looking at their history, researchers found that 61% had chronic pain at the start. So most dementia patients had chronic pain before they were diagnosed with dementia.
This study also looked at how this might happen. Chronic pain raises the levels of certain inflammation chemicals in the brain. It raises tumor necrosis factor-alpha, which is known to switch on microglia, and that inflames the brain. So people with chronic pain are also more likely to have higher beta-amyloid and tau proteins in their cerebrospinal fluid. That is the fluid around the brain and spinal cord. This suggests that chronic pain may raise the risk of dementia or Alzheimer’s, or may act as a trigger.
For doctors, this study shows how important it is to treat chronic pain, especially in people at high risk of dementia. It also means chronic pain may speed up dementia, too.
Of course, the study has many limits. It is more of a small first study (a pilot). It did not look at whether worse pain goes with more nerve damage markers. So it did not test whether more severe pain goes with a higher dementia risk.
Still, the study shows that chronic pain is likely one of the risk factors for dementia, especially in older adults.
Why does managing chronic pain matter for older adults?
Chronic pain disorder is common and has many causes. Often, the cause of chronic pain is not fully understood. The same is true for dementia. It is becoming more common, and its cause is still poorly understood. Now a new study shows that poorly treated chronic pain, especially in older adults, may trigger dementia or make it worse. That shows how important it is to treat chronic pain well in older adults.
Frequently asked questions
Does chronic pain cause dementia?
Chronic pain is unlikely to be the main cause of dementia, but it seems to be one of the factors. In a study of 995 people with dementia, most with Alzheimer’s, 61% already had chronic pain at the start. Pain may raise the risk, act as a trigger, or make dementia that has already started get worse faster.
How does chronic pain affect the brain?
Long-lasting pain raises inflammation chemicals in the brain, including tumor necrosis factor-alpha. That chemical switches on microglia, the brain’s immune cells, and the brain becomes inflamed. People with chronic pain in the study were also more likely to have higher beta-amyloid and tau proteins in the fluid around the brain and spine. Those are markers linked to damage in nerve cells.
Does more severe pain mean a higher dementia risk?
That is still unknown. This was more of a small first study. It did not test whether worse pain goes with more nerve damage or a higher dementia risk. What it does show is that chronic pain is likely one of the risk factors for dementia in older adults. That is why getting pain under control matters, especially for people already at higher risk.
Source:
Sadlon, A., Takousis, P., Ankli, B., Alexopoulos, P., Perneczky, R., & Alzheimer’s Disease Neuroimaging Initiative. (2023). Association of Chronic Pain with Biomarkers of Neurodegeneration, Microglial Activation, and Inflammation in Cerebrospinal Fluid and Impaired Cognitive Function. Annals of Neurology. https://doi.org/10.1002/ana.26804
Dr. Gurpreet Singh Padda, MD, MBA, MHP
