Another in my very occasional series of articles on depression – my depression. They are written from a very personal perspective; they are my views of how I see things working and what it feels like on the inside. Your views and experiences may be vastly different. My views and experiences are not necessarily backed by scientific evidence or current medical opinion. These articles are not medical advice or treatment pathways. If you think you have a problem then you should talk to your primary care physician.
It’s a couple of years since I wrote about depression, and as I said last time it’s not that my depression has improved; if anything the opposite. There just doesn’t seem to have been a lot new to say.
However in the last couple of weeks there have been two major articles (one in New Scientist [£££], the other in Quanta).
Both articles report on (the same) research which suggests that the physiological causes of depression are a lot more complicated than the current model – which blames it all on the activity of serotonin.
We know some part of depression has a genetic cause. It is thought up to 40% is genetic, although only 5% is currently proven. But there are molecules other than serotonin which are being implicated. Unsurprisingly some are in the metabolic pathway of serotonin, and all seem to be doing things other than just increasing serotonin levels. This could account for a significant number of depressives not responding (or not responding well) to drugs which target only serotonin.
One leading theory is that the chemistry of the serotonin pathway is majorly affected by chronic, systemic inflammation. Certainly people with chronic inflammatory diseases like lupus and rheumatoid arthritis are known to be more prone to depression. It is also a component of Long Covid and other post-viral syndromes.
There is also evidence, that depression can be affected, if not directly caused, by the action of some bacteria in the gut microbiome. It is known that much of our serotonin and its precursors are produced in the gut. What isn’t known is precisely how this affects brain metabolism. But there are reports, many anecdotal, that taking probiotics can release depression. But it doesn’t work for everyone. It doesn’t obviously work for me.
There are then the psychological factors which may trigger those otherwise vulnerable to depression, or may exacerbate a pre-existing condition. However it seems unlikely that psychology is the sole cause.
The net result is “It’s complicated”, and it could turn out that “depression” is really an umbrella covering a multitude of different causes. We’re therefore going to need a range of medical interventions to follow on from a way of establishing the differential diagnoses.
Meanwhile I keep wondering what state I’d be in without SSRI antidepressants. Would I be worse? Are they really doing any good? Is there likely to be anything better? I don’t know the answer, and to be frank, I’m frightened to try finding out.
It’s a bugger.