Summary: Researchers found a significant, albeit small, correlation between inflammation levels and the future risk of dementia.
In a study involving data from nearly 500,000 participants of the UK Biobank, the team evaluated inflammatory biomarkers and their relation to cognitive performance and later dementia diagnosis.
While this association does not imply causation, it suggests that systemic inflammation may be a contributing factor to dementia. Further research is needed to better understand this connection and its potential clinical applications.
Key Facts:
- A study of nearly 500,000 participants from the UK Biobank found a small but statistically significant association between higher systemic inflammation levels and a future risk of dementia.
- The analysis also showed that elevated inflammatory biomarkers were linked to worse performance on cognitive measures related to prospective memory, fluid intelligence, and reaction time.
- While this study does not prove causation, it suggests that measuring inflammatory biomarkers could be useful in identifying people at higher risk of developing dementia.
Source: PLOS
A study of data from about 500,000 people in the UK Biobank has uncovered small but statistically significant associations between signs of systemic inflammation and later risk of dementia.
Dr. Krisztina Mekli of The University of Manchester, UK, and colleagues present these findings in the open-access journal PLOS ONE on July 19, 2023.
Millions of people around the world have Alzheimer’s disease or other types of dementia, and researchers are working to tease out the complex mechanisms behind these conditions.
Prior research has suggested that inflammation—activation of the body’s innate immune system—may play a contributing role in the onset of dementia.
To help clarify this potential role, Dr. Mekli and colleagues analyzed data from nearly 500,000 participants in a large, multifaceted health study called the UK Biobank.
They evaluated the relationship between certain biological measures—biomarkers—of inflammation and participants’ performance on various cognitive tests, assessed both at the same time as the biomarkers and years later, as well as if they were later diagnosed with dementia.
The analysis accounted for various demographic factors, other health factors, and whether participants had a variant of the APOE gene that is known to be associated with higher risk of dementia.
The researchers found that higher levels of inflammatory biomarker levels were associated with increased risk of dementia diagnosis three to eleven years later.
Elevated inflammatory biomarkers were also associated with worse performance on certain cognitive measures, including tasks related to prospective memory, fluid intelligence, and reaction time, both at baseline and four to thirteen years later.
These associations were small, but they were statistically significant, suggesting that systemic inflammation may contribute to dementia. While other known biomarkers, such as APOE status, appear to have a stronger association with dementia, it is possible that measuring inflammatory biomarkers could be an additional useful tool for identifying people who may be at higher risk of developing dementia.
The authors note that this study is exploratory and that further research will be needed to better understand the inflammation-dementia link and its potential clinical applications.
Dr. Mekli adds: “In this study, we found associations between higher systemic inflammation levels and risk of being diagnosed with dementia 3-11 years later, although the increase in risk is small.
“This association of course does not mean causality, therefore further research is needed to understand and evaluate the potential mechanism. In addition, high levels of inflammation might be one of the biomarkers which helps to identify people who have elevated risk of developing dementia in the near future.”
About this inflammation and dementia research news
Author: Hanna Abdallah
Source: PLOS
Contact: Hanna Abdallah – PLOS
Image: The image is credited to Neuroscience News
Original Research: Open access.
“Association between an inflammatory biomarker score and future dementia diagnosis in the population-based UK Biobank cohort of 500,000 people” by Krisztina Mekli et al. PLOS ONE
Abstract
Association between an inflammatory biomarker score and future dementia diagnosis in the population-based UK Biobank cohort of 500,000 people
This study was designed to investigate the relationship between a systematic inflammatory biomarker measure, concurrent and later cognitive performance, and future dementia risk.
The literature has reported the potential involvement of inflammation in cognitive performance as well as Alzheimer’s Disease, but not consistently.
We used a population-based cohort of 500,000 people in the UK and assessed the association between a composite inflammatory biomarker and cognitive performance measures across five domains measured concurrently and 4–13 years later, taking advantage of the large sample size.
We also assessed the same biomarker’s association with dementia diagnosis 3–11 years later in the initially dementia-free sample. We report small but significant associations between elevated biomarker levels and worsened cognitive performance at baseline for four cognitive tasks (OR = 1.204, p<0.001 for Prospective memory, β = -0.366, p<0.001 for Fluid intelligence, β = 8.819, p<0.001 for Reaction time, and β = -0.224, p<0.001 for Numeric memory), comparing the highest quartile of the biomarker to the lowest.
We also found that for one measure (Pairs matching) higher biomarker levels were associated with fewer errors, i.e. better performance (β = -0.096, p<0.001).
We also report that the 4th quartiles of the baseline biomarker levels were significantly associated with cognitive task scores assessed years later on the p< = 0.002 level, except for the Pair matching test, for which none of the quartiles remained a significant predictor.
Finally, the highest biomarker quartile was significantly associated with increased dementia risk compared to the lowest quartile (HR = 1.349, p<0.001).
A case-only analysis to assess disease subtype heterogeneity suggested probable differences in the association with the highest biomarker quartile between vascular dementia and Alzheimer disease subtypes (OR = 1.483, p = 0.055).
Our results indicate that systemic inflammation may play a small but significant part in dementia pathophysiology, especially in vascular dementia.
