Early Inflammation Linked to Midlife Cognitive Decline.
Imagine your body as a well-oiled machine. When you get injured or sick, it sends out inflammatory compounds to heal the damage. This is called acute inflammation, and it’s crucial for recovery.
But there’s another kind of inflammation, a chronic one, that lingers and attacks healthy tissue. This often stems from factors like long-term stress, poor sleep, smoking, inactivity, obesity, and even certain chemicals in food. Chronic inflammation is linked to various health issues, including arthritis, heart disease, cancer, and diabetes.
There’s also a connection between chronic inflammation and dementia, including Alzheimer’s disease. Many cognition studies focus on inflammation later in life, but a new study published in Neurology on July 3, 2024, highlights the importance of addressing chronic inflammation early on [1].
The Study: Early Signs Matter
Researchers from the University of California, San Francisco, analyzed data from the CARDIA study, which tracks young adults to identify factors leading to later heart disease [1]. The study involved 2,364 participants, roughly 55% female, aged 18-30 at the outset.
Researchers considered factors like depression history, alcohol use, smoking habits, physical activity, and body mass index (BMI) during analysis. They also tested participants in year seven for a gene linked to a higher Alzheimer’s risk.
Blood tests measured C-reactive protein (CRP) levels, an inflammation marker, four times over the first 18 years. Participants also underwent cognitive tests five years after the final CRP test. The aim was to identify a link between early adulthood inflammation and later cognitive function.
Participants were categorized into three inflammation trajectories based on CRP results: lower stable CRP, moderate/increasing CRP, or consistently higher CRP. The results showed:
39% had consistently higher CRP levels.
16% had moderate/increasing CRP.
45% had lower stable CRP.
Researchers then compared each participant’s inflammation trajectory with their cognitive test results to assess connections between inflammation levels and various cognitive functions.
The Takeaway: Prevention is Key
The study suggests that moderate/increasing or consistently high inflammation levels in early adulthood can increase the risk of poor cognitive function in midlife.
Those with moderate/increasing or consistently higher CRP had over double the odds of performing poorly in processing speed tests compared to the lower stable CRP group. Processing speed refers to how quickly the brain receives, understands, and reacts to information. Similar results were observed for executive functioning, which involves higher-level cognitive skills for managing and coordinating other cognitive abilities and behaviors.
It’s important to note that these participants were tested in their early 40s to late 50s, highlighting that brain changes associated with cognitive decline begin much earlier.
« Long-term studies suggest brain changes leading to Alzheimer’s and other dementias can develop over decades, » says the study’s lead author, Dr. Amber Bahorik [2]. « We aimed to see if health and lifestyle habits in early adulthood might influence cognitive skills in midlife, which could in turn affect the likelihood of dementia later in life. »
This study emphasizes the importance of prevention. Certain lifestyle factors influence inflammation, so focusing on modifiable behaviors like stress management, sleep hygiene, physical activity, and diet is crucial. While obesity is a risk factor for inflammation, it’s not a behavior itself. It’s more important to target healthy habits that influence weight, which often coincide with those that reduce inflammation.
The bottom line? This study suggests that moderate/increasing and higher inflammation levels in young adults may negatively impact cognitive function in midlife, potentially increasing the risk of developing dementia later. While genetics play a role in inflammation and brain health, so do lifestyle choices. If you smoke, seek help quitting. If you drink alcohol, ensure moderation – excessive alcohol consumption is linked to inflammation. Move your body regularly, manage stress, prioritize quality sleep, and incorporate more anti-inflammatory foods into your diet. Consider the MIND diet, an eating pattern specifically designed for brain health.
