Predictors of “brain fog” 1 year after COVID-19 disease, 2022, Cristillo et al

Abstract

Introduction
Brain fog has been described up to 1 year after SARS-CoV-2 infection, notwithstanding the underlying mechanisms are still poorly investigated. In this study, we aimed to evaluate the prevalence of cognitive complaints at 1-year follow-up and to identify the factors related to persistent brain fog in COVID-19 patients.

Methods
Out of 246 COVID patients, hospitalized from March 1st to May 31st, a sample of 137 patients accepted to be evaluated at 1 year from discharge, through a full clinical, neurological, and psychological examination, including the Montreal Cognitive Assessment (MoCA), impact of event scale-revised (IES-R), Zung self-rating depression scale (SDS), Zung self-rating anxiety scale (SAS), and fatigue severity scale (FSS). Subjects with prior cognitive impairment and/or psychiatric disorders were excluded.

Results
Patients with cognitive disorders exhibited lower MoCA score (22.9 ± 4.3 vs. 26.3 ± 3.1, p = 0.002) and higher IES-R score (33.7 ± 18.5 vs. 26.4 ± 16.3, p = 0.050), SDS score (40.9 ± 6.5 vs. 35.5 ± 8.6, p = 0.004), and fatigue severity scale score (33.6 ± 16.1 vs. 23.7 ± 12.5, p = 0.001), compared to patients without cognitive complaints. Logistic regression showed a significant correlation between brain fog and the self-rating depression scale values (p = 0.020), adjusted for age (p = 0.445), sex (p = 0.178), premorbid Cumulative Illness Rating Scale (CIRS) (p = 0.288), COVID-19 severity (BCRSS) (p = 0.964), education level (p = 0.784) and MoCA score (p = 0.909).

Conclusions
Our study showed depression as the strongest predictor of persistent brain fog, adjusting for demographic and clinical variables. Wider longitudinal studies are warranted to better explain cognitive difficulties after COVID-19.

Paywall, https://link.springer.com/article/10.1007/s10072-022-06285-4

 

"Our study showed depression as the strongest predictor of persistent brain fog"

"Zung self-rating depression scale"

You can view take this questionnaire here, https://psychology-tools.com/test/zung-depression-scale

The questions on it are

1. I feel down hearted and blue.
2. Morning is when I feel the best.
3. I have crying spells or feel like it.
4. I have trouble sleeping at night.
5. I eat as much as I used to.
6. I still enjoy sex.
7. I notice that I am losing weight.
8. I have trouble with constipation..
9. My heart beats faster than usual.
10. I get tired for no reason.
11. My mind is as clear as it used to be.
12. I find it easy to do the things I used to.
13. I am restless and can’t keep still.
14. I feel hopeful about the future.
15. I am more irritable than usual.
16. I find it easy to make decisions.
17. I feel that I am useful and needed.
18. My life is pretty full.
19. I feel that others would be better off if I were dead.
20. I still enjoy the things I used to do.


and answer choices are A Little Of The Time, Some Of The Time, Good Part Of The Time and Most Of The Time

I'm sure that we can all see that somebody suffering brain fog and, most likely, other symptoms of Long Covid are going to naturally score higher, even if they aren't depressed, so yet another bad scale.

 

Is it depression if someone with an incurable illness that is not taken seriously does not feel hopeful about the future? Or just a realistic assessment, and when that hopelessness is expressed to another person, a way to communicate that help is needed? Why pathologize that? It seems cruel and out of touch with reality.

Sometimes I get the impression that depression is a fluid concept that is whatever psychaitrists want it to be at the moment. Sometimes it's stronger than normal presence of negative emotions irrespective of circumstances. At other times it's some kind of illness of the brain with dysfunction in specific pathways (not yet clearly identified) that manifests with symptoms like inability to enjoy things or pessimistic outlook not matching the life circumstances.

 

This is like research studying the hardship of poverty, then concluding that it's negative attitudes that cause poverty.

"I don't have enough money to pay for bills"
Wow, negative much.
"I am not optimistic about the future"
Wow, much depression.
"I don't know how I'm going to pay my bills"
Have some self-efficacy, man up.

Basically a definition of depression that completely overlaps with illness. Like saying "yeah, there is no evidence this person is guilty, but they look the profile and my gut tells me they did it".

 

I never realised that constipation was considered to be an aggravating factor in developing depression. Personally, I'd me more depressed if I had diarrhoea.

There are lots of reasons for having a faster heart rate than usual that have nothing to do with depression. I can create a faster heart rate in myself by drinking more coffee than usual, and by eating too much sugary junk. Doesn't mean I'm depressed, it just means I am greedy for carbs, and I like coffee.

I fixed my own irritability years ago by giving up gluten.

I could probably make up some sensible reasons for most of the negative comments in the questionnaire. Still doesn't mean I'm depressed.

 

I think a similar argument can be made about anxiety in ME and other incurable diseases.

 

I was actually curious about what this means, or how it even relates to whatever they mean by depression. Are the morning people depressed? Or the evening people? What does that even have to do with depression, even as a vague, generic concept? Whoever decided that and what the hell is it even doing there as a question relating to this?

It's all so completely arbitrary. And to claim this is what depression is, I am really getting around to the fact that there is basically no such thing and no one has a damn idea what they're talking about most of the time.

Frankly I don't think anyone has done more harm to mental health than the mental health profession. They completely botched the whole thing and now it's too late to start over so all the baggage and mythology just carries over. Foundations made of quicksand are more reliable than this.

 

This paper is a lapse of basic logic. They assume brain fog causes the depression because they're correlated. The second possibility is that brain fog is causing the depression, which many of you have cited. But there's also the possibility that the effect of Covid-19 on the brain causes both. We know long Covid is associated with neuropsychiatric changes.

 

This kind of thing is always a possibility. The example I have used many times is that obesity and tooth decay are associated to some degree. I would not want to claim either caused the other though. Sugar intake, for example, could cause both. Association does not tell you about causation unless you have measurable mechanisms that have been demonstrated.

 

Exactly. The questions used are not sufficiently specific or validated.

 

Exactly. I can only hold one idea in my head at once . I've personally faced with this problem. My therapist gave me the Beck Depression Inventory that asked about things like your ability to work. We agreed that I'd "lie" on the questionnaire by only considering the effect of my mental health. Any researcher worth their salt needs to use a depression questionnaire that works in chronic illness. I know there's one out there but don't remember the name.

 

Also, though it does not demonstrate causality either, the sequence of events needs to be consistent. If the presumed depression predates the Long Covid then it is consistent with it having a causal relationship, though this is not of itself proof. If the Long Covid predates the presumed depression then it is improbable that it has a causal relationship.

It is hard to say when the acute Covid ended and Long Covid began, but it is likely that any real depression or anxiety, rather than as an artefact of poorly designed questionnaires, began after the onset of the physical symptoms, suggesting any causal relationship in the direction posited by the authors would have to magically have an effect that predated its cause.

 

Perhaps not necessarily. I recall that Wittgenstein posited the idea of "unconscious" toothache. I forget the details and would have to look them up. He suggested that this was possible and merely a novel and previously unrecognised use of the words. I doubt whether it would apply here.

 

Was this questionnaire written by a frustrated blues musician?

A guaranteed "Yes" from anyone who's just had this questionnaire shoved under their nose and had to answer the previous 14 questions.

Seriously? Only people who answer yes will be able to answer this one at all. Everyone else will just get stuck in an endless loop trying to decide between A Little Of The Time, Some Of The Time, Good Part Of The Time and Most Of The Time