Inflammation's Impact on Reward Response in Aging and Anxiety

(ARIA Trial)

This trial aims to understand how inflammation might affect joy and drive in older adults with anxiety. Researchers will administer a small dose of endotoxin, a substance that causes inflammation, to observe its impact on moods and motivation, comparing these effects to a placebo, a harmless substance. The trial uses questionnaires, computer tasks, and brain scans to gather data. It seeks participants aged 60 to 80 who have significant anxiety and are in good health, without chronic illnesses or frequent medication use. Participants must not have severe medical conditions or recent changes in time zones.

As a Phase 1 trial, the research focuses on understanding how the treatment works in people, offering participants the opportunity to contribute to groundbreaking research.

Yes, you will need to stop taking certain medications. The trial excludes participants who currently use prescription medications like steroids, anti-inflammatory drugs, antidepressants, and several others. You must not have used these medications in the last 6 months.

Research has shown that using endotoxin as a treatment is generally safe for people. Studies have found that while endotoxins can cause temporary discomfort or sickness, they do not lead to long-term harm in humans.

Some animal studies, such as those with mice, have suggested that endotoxins might affect behavior and thinking, potentially causing more anxiety-like behavior. However, these effects may not occur in humans.

Researchers are excited about this trial because it explores how inflammation might affect how older adults with anxiety experience rewards. Unlike standard treatments that typically focus on reducing anxiety symptoms through medications like SSRIs or therapy, this trial investigates the biological link between inflammation and brain responses to rewards. By using a controlled dose of endotoxin to induce inflammation, researchers aim to understand its direct impact on the brain's reward system. This could open new pathways for treating anxiety by targeting inflammation rather than just managing symptoms.

This trial will compare the effects of endotoxin with a placebo to study its impact on anxiety and motivation in aging. Research has shown that endotoxin, a component of some bacteria, can influence emotions and behavior. Studies have found that when endotoxin enters the body, it can increase anxiety and decrease motivation, particularly in older adults. This occurs because endotoxin can cause inflammation, altering how the brain responds to rewards and making activities less enjoyable or motivating. Older individuals are more affected by this inflammation. These findings clarify why researchers are studying endotoxin's effects on anxiety and motivation in aging.⁶⁷⁸⁹¹⁰