Increased inflammation over a long period may cause dementia

Researchers from The University of Manchester, UK, have found a significant connection between signs of inflammation and the risk of developing dementia. Their findings published in the journal PLOS ONE on 19 July demonstrate that certain inflammatory biomarkers could serve as early indicators of dementia risk.

Dementia, which affects millions of people worldwide, causes loss of memory and the ability to think. on the possible connection between increased inflammatory responses of the immune system and dementia. However, the exact link between signs of inflammation and dementia diagnosis had not been explored until now.

Biomarker clue

To shed light on this link, Dr Krisztina Mekli, the lead author of this study and her team examined the medical data of approximately 5,00,000 individuals from the UK Biobank study. They specifically focused on the correlation between various biomarkers of inflammation and individuals’ performance on cognitive tests such as memory and thinking.

Additionally, the study took into account demographic factors such as age, sex and other health conditions, along with the presence of the APOE gene, which is linked to an increased risk of dementia.

Read more – Decoding the genetics of Alzheimer’s: the role of APOE4 and SHMOOSE

The evaluations were conducted during the biomarker assessment and in subsequent years. Additionally, the researchers investigated if individuals with higher levels of inflammation were later diagnosed with dementia.

Cascading changes

Systemic inflammation or full-body inflammation is the body’s response to stressors such as illness or trauma. It causes a cascade of chemical reactions in the body, and individuals experience headaches, fever and body aches along with the common cold.

The researchers observed that individuals with higher systemic inflammation performed poorly in cognitive tasks related to memory, intelligence, and reaction time—both during the first assessment and four to thirteen years later.

They also found that individuals who had higher inflammatory biomarkers were diagnosed with dementia within three to eleven years. “In this study, we found associations between higher systemic inflammation levels and risk of being diagnosed with dementia 3-11 years later,” said Dr Mekli in a statement.

Glimmer of hope

Despite direct associations being small, the statistical significance is high, say researchers. “Although the increase in risk is small, high levels of inflammation might serve as one of the biomarkers that help identify individuals at elevated risk of developing dementia in the near future,” says Dr Mekli.

However, further investigations are necessary to understand the clinical applications of measuring inflammatory biomarkers, researchers say.  “This association, of course, does not imply causality, and therefore, further research is needed to understand and evaluate the potential mechanism,” Dr Mekli says in the statement.