Brain Fog and Sleep Issues in AiArthritis Diseases

Brain fog is one of those symptoms patients talk about all the time, yet it is still often misunderstood or minimized in clinical care. At the American College of Rheumatology convergence in 2025, several sessions finally put this experience front and center, starting with patient voices and moving into emerging science. The takeaway was clear. Brain fog is real, it is disruptive, and sleep plays a much bigger role than many people realize.

These conversations, shared through the video debrief “What Research Reveals About Brain Fog & Sleep in AiArthritis,” helped bridge the gap between lived experience and research. 

This video debrief was created as part of AiArthritis’“Go With Us!” to Conferences program.

What Brain Fog Actually Feels Like for Patients

The first session centered on the patient perspective, with a patient speaking directly to rheumatologists about how brain fog affects daily life. Brain fog is not just about forgetting a dose of medication or misplacing keys. It can shape the entire day.

Many patients notice that cognitive function worsens as the day goes on. Tasks that feel manageable in the morning become overwhelming later, especially after pain, fatigue, or stress accumulate. Concentration drops, word recall becomes harder, and decision-making can feel exhausting. This cumulative effect is something patients experience every day, yet it is rarely captured in a clinic visit.

What Cognitive Testing Is Showing in Fibromyalgia

Researchers then shared data from fibromyalgia studies, where brain fog has been more formally studied. Cognitive testing showed that as the day progresses, people with fibromyalgia often perform worse on memory and response tasks.

The audience was asked to try some of these tests themselves, such as remembering images flashed on a screen or quickly ordering animals by size. Even without chronic illness, these tasks were challenging. After a long day or during a flare, they become even more difficult.

Researchers made an important acknowledgment that testing cognitive function only in a clinic setting may miss the full picture. Cognitive clarity can vary hour by hour depending on pain, fatigue, stress, and sleep. To address this, researchers are now using apps and text-based check-ins to collect data throughout the day. This allows them to track exactly when patients feel clear, when fog sets in, and possible triggers.

The Gap in Rheumatoid Arthritis Research

One surprising finding was how little research exists on brain fog in rheumatoid arthritis (RA). Despite how common it is for RA patients to report cognitive issues, formal studies have been scarce.

When researchers did look at available data, many standard cognitive tests showed results similar to those for people that are not living with RA. On paper, everything looked normal. But patients consistently reported feeling cognitively impaired. This highlighted a critical gap between perceived cognitive function and what traditional tests measure. In other words, patients feel brain fog, but current tools are not capturing it well.

When researchers dug deeper using alternative methods, patterns began to emerge. Memory, particularly verbal and short-term memory, appeared to be affected. Higher disease activity, moderate to high disease severity, oral steroid use, and rheumatoid factor positivity were all associated with greater cognitive dysfunction.

These findings suggest that something real is happening, even if standard tests are not yet sensitive enough to detect it. Researchers are now planning further studies to better understand and measure brain fog in RA.

Sleep Is a Common Thread Across Conditions

One theme echoed across nearly every session at ACR: sleep matters more than we think. Poor sleep is linked to faster aging, worse cognitive function, increased pain sensitivity, and impaired metabolism and digestion. When sleep is disrupted, brain fog becomes more severe, fatigue worsens, and the body has fewer resources to cope with inflammation.

For people living with rheumatoid arthritis in particular, researchers noted higher rates of sleep apnea than in the general population. This is important because untreated sleep apnea can significantly worsen fatigue, cognitive issues, and cardiovascular risk.

What This Means for Patients

The biggest validation from these sessions was hearing researchers say out loud what patients have long known. Brain fog is not imagined. It is not just stress or distraction. It is a real symptom that fluctuates throughout the day and is influenced by disease activity, medication use, and sleep quality.

If brain fog is affecting daily life, it may help to talk with your care team about patterns you notice. When does it get worse? Is it tied to poor sleep, flares, or medication changes? Asking about sleep quality and screening for conditions like sleep apnea may be an important step, especially if fatigue and cognitive issues feel overwhelming.

Looking Ahead

Research on brain fog is still catching up to patient experience, but momentum is building. Better measurement tools, real-time data collection, and greater attention to sleep are opening the door for more effective ways of addressing cognitive symptoms in autoimmune and autoinflammatory arthritis diseases.

For now, the message is both validating and practical. Brain fog is real. Sleep is foundational. And paying attention to how symptoms change throughout the day can help guide more meaningful conversations and better care.