Treatment of 95 post-Covid patients with SSRIs

[SWAlexander]

Abstract​

After Covid-19 infection, 12.5% develops post-Covid-syndrome (PCS). Symptoms indicate numerous affected organ systems. After a year, chronic fatigue, dysautonomia and neurological and neuropsychiatric complaints predominate. In this study, 95 PCS patients were treated with selective serotonin reuptake inhibitors (SSRIs). This study used an exploratory questionnaire and found that two-thirds of patients had a reasonably good to strong response on SSRIs, over a quarter of patients had moderate response, while 10% reported no response. Overall, patients experienced substantial improved well-being. Brainfog and sensory overload decreased most, followed by chronic fatigue and dysautonomia. Outcomes were measured with three different measures that correlated strongly with each other. The response to SSRIs in PCS conditions was explained by seven possible neurobiological mechanisms based on recent literature on PCS integrated with already existing knowledge. Important for understanding these mechanisms is the underlying biochemical interaction between various neurotransmitter systems and parts of the immune system, and their dysregulation in PCS. The main link appears to be with the metabolic kynurenine pathway (KP) which interacts extensively with the immune system. The KP uses the same precursor as serotonin: tryptophan. The KP is overactive in PCS which maintains inflammation and which causes a lack of tryptophan. Finally, potential avenues for future research to advance this line of clinical research are discussed. https://www.nature.com/articles/s41598-023-45072-9

 

[SWAlexander]

Article:​

Serotonin Slump: The Viral Residue Connection to Long COVID Symptoms​

 

[hapl808]

This study used an exploratory questionnaire and found that two-thirds of patients had a reasonably good to strong response on SSRIs, over a quarter of patients had moderate response, while 10% reported no response.

It's a long study so I haven't read it, but I am immediately suspicious of an SSRI study where some had a good response, some had a moderately good response, some had no response - but are they saying nobody at all had a bad response? That seems…unlikely.

 

[SWAlexander]

That seems…unlikely.

My question would be why not everyone responds to SSRIs? There can be various reasons why someone might not experience an improvement.

One would be genetic variations.
Some people have genetic differences that make them less responsive to certain SSRIs.
Example:
Pharmacogenetic tests can look at specific genes that are known to influence the metabolism of SSRIs. For example, genes like CYP2D6 or CYP2C19 encode enzymes that are responsible for metabolizing many SSRIs.

Tetrahydrobiopterin (BH4) is a naturally occurring compound that is essential for the activity of several enzymes, including those involved in the synthesis of neurotransmitters. Serotonin is a naturally occurring monoamine neurotransmitter that carries signals between nerve cells throughout your body. BH4 is a cofactor for the enzyme tryptophan hydroxylase, which is responsible for the conversion of the amino acid tryptophan into 5-hydroxytryptophan (5-HTP), the immediate precursor to serotonin.

Second, were there any previous tests for serotonin high or deficiency?

Also, I could not find any results indicating if participants were tested for Addison's disease (chronically low cortisol) or Cushing's syndrome (chronically high cortisol), Very important if SSRIs were given.

It seems, that research is still fishing in the dark.