Somatic symptoms mediate the association between subclinical anxiety and depressive symptoms and its neuroimaging mechanisms 2022 Kong et al

Abstract
Background

Subclinical anxiety, depressive and somatic symptoms appear closely related. However, it remains unclear whether somatic symptoms mediate the association between subclinical anxiety and depressive symptoms and what the underlying neuroimaging mechanisms are for the mediating effect.

Methods
Data of healthy participants (n = 466) and participants in remission of major depressive disorder (n = 53) were obtained from the Human Connectome Project. The Achenbach Adult Self-Report was adopted to assess anxiety, depressive and somatic symptoms. All participants completed four runs of resting-state functional magnetic resonance imaging. Mediation analyses were utilized to explore the interactions among these symptoms and their neuroimaging mechanisms.

Results
Somatic symptoms partially mediated the association between subclinical anxiety and depressive symptoms in healthy participants (anxiety→somatic→depression: effect: 0.2785, Boot 95% CI: 0.0958–0.3729; depression→somatic→anxiety: effect: 0.0753, Boot 95% CI: 0.0232–0.1314) and participants in remission of MDD (anxiety→somatic→depression: effect: 0.2948, Boot 95% CI: 0.0357–0.7382; depression→somatic→anxiety: effect: 0.0984, Boot 95% CI: 0.0007–0.2438). Resting-state functional connectivity (FC) between the right medial superior frontal gyrus and the left thalamus and somatic symptoms as chain mediators partially mediated the effect of subclinical depressive symptoms on subclinical anxiety symptoms in healthy participants (effect: 0.0020, Boot 95% CI: 0.0003–0.0043). The mean strength of common FCs of subclinical depressive and somatic symptoms, somatic symptoms, and the mean strength of common FCs of subclinical anxiety and somatic symptoms as chain mediators partially mediated the effect of subclinical depressive symptoms on subclinical anxiety symptoms in remission of MDD (effect: 0.0437, Boot 95% CI: 0.0024–0.1190). These common FCs mainly involved the insula, precentral gyri, postcentral gyri and cingulate gyri. Furthermore, FC between the triangular part of the left inferior frontal gyrus and the left postcentral gyrus was positively associated with subclinical anxiety, depressive and somatic symptoms in remission of MDD (FDR-corrected p < 0.01).

Conclusions
Somatic symptoms partially mediate the interaction between subclinical anxiety and depressive symptoms. FCs involving the right medial superior frontal gyrus, left thalamus, triangular part of left inferior frontal gyrus, bilateral insula, precentral gyri, postcentral gyri and cingulate gyri maybe underlie the mediating effect of somatic symptoms.

Open access, https://bmcpsychiatry.biomedcentral.com/articles/10.1186/s12888-022-04488-9

 

I am obviously befuddled as i cant understand their meaning....What do they mean when they use the term 'mediate' in this context? I understand the verb to mediate, to be mediating between 2 parties eg neighbours who are in conflict.

I dont understand what they are saying somatic symptoms do? Sorry to be so thick lol

 

https://www.merriam-webster.com/dictionary/mediate:

a) acting through an intervening agency

b) exhibiting indirect causation, connection, or relation the disease spreads by mediate as well as direct contact— Veterinary Record

a) to act as intermediary (see intermediary entry 2 sense 2) agent in bringing, effecting, or communicating : convey individuals … mediate the culture to the child — Margaret Mead

b) to transmit as intermediate mechanism or agency

I think the senses b) & b) are those that apply in the study.

 

It's really wild seeing medicine dance around the fact that symptoms are actually relevant, not just as a factor for differential diagnosis, but being unable to understand how, since they literally made the concepts of depression and anxiety meaningless by attributing symptoms the wrong way.

Especially with such nonsense as "subclinical" anxiety or depression. The ability of medicine to dismiss chronic illness because they never bothered doing the work to develop the tests, but are perfectly willing to attribute any and all things to such vague generic concepts that are even less well-defined, and not only don't have any tests, but actually ask about symptoms to somehow reattribute in a backward way.

The very concept of "subclinical" subjective something, where the patient isn't aware of but the physician is, is legitimately insane. It goes beyond claiming they know what we think, they think they can tell us what we think even when we don't know ourselves. Beyond absurd this is madness.

Honestly this has actually reached a level above the standard lies, damned lies and statistics. This is at a narrative level, you can't even talk about statistics here, the numbers are all made-up and overlap with each other. It's actually out-quackering even the worst historical quacks.