Epidemiology of paediatric chronic fatigue syndrome in Australia, 2019, Knight et al

Not for me. In the UK it says I have to pay £27.60 for the full text.

 

It's a useful study. One problem is the commentary around rates of depression and anxiety in first degree relatives.

This makes it sound as though young people diagnosed with CFS are more likely to have first degree relatives with anxiety or depression than young people without CFS. But no comparable rates are given for young people without CFS. Here's some data on depression and anxiety rates from Beyond Blue - an Australian mental health charity:

Message: One in seven Australians will experience depression in their lifetime.
Breakdown: 15.0% of Australians aged 16 to 85 have experienced an affective disorder1* This is equivalent to 2.83 million people today.

Message: One quarter of Australians will experience an anxiety condition in their lifetime.
Breakdown: 26.3% of Australians aged 16 to 85 have experienced an anxiety disorder.2** This is equivalent to 4.96 million people today.​

Anxiety disorders and depression appear to be extremely common in the general Australian population. Therefore the rates of depression and anxiety disorders in first degree relatives of young people with CFS (that's the siblings and parents) don't look particularly interesting.

The rate of CFS in first degree relatives (13.4%) is pretty high though, given the much lower incidence in the general population.

 

Anxious/worried/sad/upset are all different things to having an anxiety disorder or depression. But sure, we might hypothesise that a parent of a child with ME is more likely to have an anxiety disorder or have clinical depression as a reaction to the difficult situation. Or that the parent might actually have CFS but be misdiagnosed as having depression. Or we might hypothesise that the depression of a parent causes CFS in the child or that there is some common genetic cause for depression, anxiety disorder and CFS.

But the data from this study did not support any association between [CFS in the young person] and [anxiety disorder or depression in first degree relatives]. That's my point - there's no evidence here of a greater incidence of anxiety disorder or depression in the first degree relatives of young people with CFS.

And yet the paper doesn't say anything like that. Instead it talks about other studies that did 'suggest a likely association'.

And that non-result and obfuscation is given a place in the Discussion.

 

I thought this was interesting:

I can't see why the ANA test would be more relevant to a paediatric population than an adult one. I think the finding that 23% of the young people tested are positive for ANA suggests that this test should be a guideline recommended test for both adults and young people.

Edit: The paper doesn't say what percentage of the young people had the ANA test though. That seems to be in an online supplement. Does anyone have access to that?