Neuropsychobiological Fingerprints of Chronic Fatigue in Sarcoidosis, 2021, Kettenbach et al

Background: Chronic fatigue is a prominent symptom in many sarcoidosis patients, affecting quality of life and interfering with treatment. This study investigated neuropsychobiological mechanisms and markers of chronic fatigue in sarcoidosis.

Methods: Thirty patients with a histological diagnosis of sarcoidosis were included. The Multidimensional Fatigue Inventory was used to define patients with and without chronic fatigue. All patients were then characterised using several depression, quality of life questionnaires, and executive functioning. Cognitive functioning and underlying neural correlates were assessed using an n-back task measuring working memory and (sustained) attention during functional magnetic resonance imaging. Sarcoidosis disease activity was determined using lung function, laboratory parameters, and exercise capacity.

Results: Nineteen patients had chronic fatigue and 11 did not; both groups had similar demographic and disease activity characteristics. Chronic fatigue patients showed more symptoms of depression and anxiety, and lower quality of life. During the n-back task, chronic fatigue was associated with a smaller increase in brain activation with increasing task difficulty versus the group without fatigue, especially in the angular gyrus.

Conclusion: Inadequate adjustment of brain activation with increasing demands appears to be a potential neurobiological marker of chronic fatigue in sarcoidosis patients. The angular gyrus, which plays an important role in the working memory system, was the major area in which fatigue patients showed smaller increase of brain activation compared to those without fatigue. These findings might be relevant for a deeper understanding of chronic fatigue mechanisms in sarcoidosis and future clinical treatment of this disabling syndrome.

Open access, https://www.frontiersin.org/articles/10.3389/fnbeh.2021.633005/full

 

I have no personal interest in sarcoidosis. I don't have it nor do I know anyone who has.

But whenever I see this kind of paper I always wonder if it is an early salvo in a war against treating a disease with anything other than psychiatric "remedies". In other words, before diagnosis the patient will be treated with anti-depressants, will be told they just need CBT and exercise. It feels as if the only point of such a paper is to find ways and means of delaying diagnosis and reducing the costs of the disease. And of course, if diagnosis and treatment are delayed then the risks of someone ending up with chronic fatigue, depression or anxiety must become much greater, thus delaying a non-psychiatric diagnosis even longer.

Oh, and when I had a quick look at the wiki link on the disease I noted that usual onset is in 20 - 50 year old women. Now there's a surprise - NOT - a disease associated with adult women is always fodder for a psychiatric treatment.

One thing that would interest me is - in the opinion of a diagnosed patient, and with hindsight - what is the relationship (if any) between when the patient first became aware of symptoms and their level of chronic fatigue, depression and anxiety. I suspect that the longer the gap (Edit: between symptom onset, and diagnosis and non-psychiatric treatment) the more likely the patient will suffer some form of psychiatric issue.