The two age peaks in onset of ME/CFS

@Jonathan Edwards, I remember that in the other place several of us had a long discussion about what could explain the two peaks in onset-age for ME/CFS.

I just saw the graph that we were discussing reproduced in Slide #25 of Karl Morten's recent talk in NZ:

https://www.meassociation.org.uk/wp...uckland-Karl-Morten-Presentation-12.12.18.pdf

On it, he says, 'Two age peaks in CFS/ME: Do they have the same cause?'

I thought that was interesting - I don't recall that we thought about the possibility that we might be looking at two different things causing the two peaks. Given that lots of roads seem to lead to ME, from burns to head trauma to infection, we could well be looking at age peaks for two different insults.

Or did this get discussed and just drain out of my head?

 

Or, it could be explained in this way. I had undiagnosed childhood onset that improved but didn't resolve completely and, I believe, the physical demands of full-time employment gradually wore me down which then led to my adult diagnosis. So the potential is there for just one cause, just diagnosis at different times for some people.

 

I find it likely it's just an artifact of bad data. The fact that it doesn't affect children was often argued, wrongly. The female:male ratio also does not seem to be as unbalanced as previously thought. And then of course it was also just a rich bored housewife disease for a long time, just because those were the only ones counted as such.

Until a public health authority actually relents and takes on the effort of gathering large scale data, we'll probably keep getting puzzled by some of those artifacts, but they're likely just gaps in data.

 

I think this was thought about a bit but not in any great detail.

I think that is unlikely, since almost no other condition has a profile like this. It is not an isolated finding either. Moreover the second peak matches the peak for Multiple Sclerosis quite closely. The reason for the peak for MS is very mysterious, since it does not fit with any simple immunological model, perhaps suggesting that the central nervous system is maximally susceptible to certain problems at that time.

And I cannot think of a very good reason why incidence in the 20s should be missed and not in the 30s.

 

Thank you @rvallee. We need public health authorities to really engage with ME. The Canadian Public Health Agency goes some way with this in including ME in the Canadian Community Health Survey, but there is much more in-depth examination to do.

Speaking of data collection, I thought the CDC was doing some sort of multi-community study. I've not seen the results of this if it has been released. Anyone know if this study has been completed?

 

Or rather than peak CNS susceptibility; peak external 'demand'?

 

Cumulative effects of, typically, full-time employment and all the other stresses and strains that come with adult life? Add on to this the delay for many in gaining an actual diagnosis? So it's not being missed as such, but there are, I believe, potential reasons why there could be a second peak.

 

I'd expect that to look more like a blur than peak.

 

That does not ring true to me. I have a daughter in her twenties and she and her peers are in the middle of maximal external demand right now. Being a teenager or a student may have been disorientating but the intense pressure from work in the early twenties is crazy. By 28 things seem to be reaching some sort of manageable level. I remember much the same as a house officer during medical training. By 30 life was a bit more predictable and manageable.

I agree that something more subtle from the outside might be triggering things but I find it hard to see what. The peaks for men and women around 30 are of different sizes but they have the same shape. I would have thought that life events were significantly different for the two sexes at this sort of time - with childbearing making the path profile different for women. But there is no hint of a different shape.

As time goes by I get more and more the feeling that our bodies are programmed to change gear each decade is really quite complicated ways. Not just sideburns going grey or midriff bulge. Some chap on the radio yesterday was taking guff about the changes in creativity with age. Talk of creativity is nearly always guff but he mentioned some quite interesting stuff about changes in neural connectivity going on into the 60s and beyond.

 

I've no doubt the 20's can be demanding - perhaps what I have in mind is salience and/or multitasking and perhaps the demands around the two peaks are different but have similar effects. Teens have to deal with the realisation that exams etc are important whilst dealing with rapid changes due to puberty; peer relationships; parental relationships etc while those in their 30's may be more settled career wise but likely now have the added responsibility of parenthood (regardless of gender). The demands for those in their 20's are largely personal but without (in most cases) the 'teenage angst'.

 

If there was some sort of cumulative effect then the prevalence would increase with every year of employment.

 

Stories about stress and overwork triggering CFS could be due to the illness slowly progressing in an individual. The first signs will be subtle and could be having to put in more effort to achieve the same results, as well as reduced stress tolerance. That's because the body is slowly shifting its resources away from "productive life" mode and towards "surviving illness" mode. You're meant to avoid stress when ill and stress intolerance is how the body achieves that.

 

I was after giving birth. I just heard of two more cases the same. I wonder if it is not what they give us like shots or the drugs for delivery?!

 

Yes. In my mild ME years I didn't know I had ME but was getting symptoms of ME. I noticed I was not handling stress at work. Before my mild onset I handled stress at work. It got to the stage in my mild years I could no longer deal with the stress so left my job. I was offered other positions that most people would have jumped at. Not me, I just wanted out - not well, not understanding what was happening to me. It's only when I look back now I can see it all. The effects ME had on me back then.

 

Maybe the peaks represent the time when you're most likely to be exposed to some virus that provokes a strong immune response. The early peak might represent when you're in school, while the later one represents when your children are bringing home viruses from school.

[The early peak around 12 years old would be the same age when, in the US at least, you go from a single grade school class of 20-30 pupils, to middle school, where you have multiple classes and are more or less mingling with the entire school (which can be several hundred to a thousand or more students in some metropolitan schools)].

 

This is exactly what happened to me.

 

Remember that we first saw two age peaks in work by Dr. David Bell, who remarked that his teenage patients would recover from ME in their early twenties, only to relapse in their mid thirties.

So, we may see two peaks not just in age at onset in separate individuals, but also in age at onset/relapse in a single individual. This may not have been clear to Morten.

We may end up having to look at complex interactions between pubertal hormonal changes and the gradual decline of the immune system as we age.

Edit: phrasing

 

Another thing that happens in MS is that many patients initially have the relapsing-remitting form of MS. This often changes into the secondary-progressive form after about 15-20 years. Another kind of two peaks pattern.

This would support the idea of increased susceptibility to certain conditions during certain life stages. Whether that is more due to environmental factors or natural physiological changes as we age is another question. I'm tending towards the latter but it could be a combination of course. Maybe for ME it's the same genetic/physiological susceptibility underlying both peaks but the final triggers could be different environmental factors that strike more commonly at particular ages?

Anecdotally, similarly to @Andy I had several bouts of ME, with good though not complete remissions inbetween, all of them about 15 years apart.

First an undiagnosed mild childhood bout. Once in remission I still retained ongoing mild OI and a reputation for being phlegmatic and lazy, or laid back and chilled, depending on how positively my disinclination for unnecessary overexertion was viewed.

The second bout was more serious and misdiagnosed for years as MS. Once in remission again, and in addition to the above, I was left with some mild neurological deficits and a peculiar tendency to 'come down with something' at least monthly. In hindsight it was clearly mild PEM. Ironically the MS diagnosis probably helped me at the time. Medications and physio rehab weren't available back then so the only “treatment” I got was a visit from an occupational therapist who taught me how to do things in a more energy-efficient way (sit down to brush teeth etc.) and to listen to my body and rest as soon as I felt tired.

The third bout is the current one and the most severe yet, leaving me housebound.

Looking back at what I just wrote I'm wondering about the impact of undiagnosed and mild cases. The two peaks in the slide obviously refer to peaks in diagnosed cases. Maybe there's something about those two age groups that makes previously unrecognised ME flare to a level that it gets diagnosed? Or maybe it's just that those two age groups that are more likely for some reason to see a doctor and seek diagnosis?

 

I don't see how that could be - each patient would only report one age of onset and wouldn't appear twice in the graph.