It makes sense that those who live with a chronic illness or disability may occasionally feel down or depressed about their health status.

But new research shows a stronger-than-expected link between serious neuropsychiatric symptoms and rheumatoid arthritis (RA).

The comprehensive review, published in Autoimmunity Reviews, concluded that not only can RA affect the joints and tendons as well as other organs, but it can also have some effect on the central nervous system, spine, and brain.

arthritis and mood

This goes far beyond mood swings.

"Neuropsychiatric manifestations — especially mood disorders and headache — are frequently observed in RA,” lead author Dr. Andrei Joaquim from the Department of Neurology at State University of Campinas (UNICAMP) in São Paolo, Brazil said in a statement. “It is of paramount importance for neurologists and rheumatologists to understand the nuances of neurological symptoms in RA patients for a proper diagnosis and an adequate treatment.”

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Mental Health Side Effects

The researchers concluded that neurological manifestations of RA could include, but are not limited to, peripheral neuropathy (nerve pain,), migraine headaches, “brain fog,” cognitive impairment, depression, anxiety, and even seizures.

Some studies have even shown links between autism spectrum disorders and inflammatory autoimmune conditions like RA. Others have investigated the prevalence of bipolar disorder with the disease.

Many studies and articles have discussed the existence of suicidal thoughts and tendencies in patients with chronic illnesses such as RA. The UNICAMP study focused mainly on headache, depression, anxiety, and cognitive impairment.

The researchers found that headaches were the leading neuropsychiatric condition found in RA patients. However, whether these headaches were from the disease process itself, co-existing health problems, or the medications used in treatment remains unknown.

The study also showed that up to 40 percent of patients acknowledge having, or have been diagnosed with, depression. That is a higher rate than the general population. The researchers found that anywhere from 21 to 70 percent of RA patients experience anxiety.

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Impaired Cognitive Functions

The researchers also concluded that patients with RA appeared to have far higher rates of cognitive dysfunction than the general population.

This was apparent mostly in areas of visual-spatial perception and planning. However, some level of cognitive dysfunction was also observed regarding impaired functional ability, reduced quality of life, and/or poor medication compliance.

The authors of the study did acknowledge that outside factors may have played a role in cognitive dysfunction among RA patients. These include low education, low income, use of oral steroids, and increased cardiovascular disease.

The symptom “brain fog” is also commonly mentioned by rheumatologists and their patients, especially those with RA and fibromyalgia, yet the lack of mental clarity remains a mystery. Researchers have yet to determine if “brain fog” stems from the diseases, the associated fatigue, the pharmaceutical drugs used in treatment, or a culmination of all of these factors.

Perhaps the most interesting part of the review is the involvement of focal/visual disturbances, the mention of stroke and seizure, and the affectation of the spine and central nervous system.

Still the biggest question remains unanswered: What is the cause?

In many cases, it’s uncertain whether the disease is actually causing these conditions, whether the sedentary lifestyle or medications taken are a factor, and whether the patients observed would have had these neuropsychiatric or mood disorders even without a diagnosis of RA.

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