In my post on the above paper I made a number of criticisms, including that the paper should have been entitled “Adverse parenting and premature mortality”. My argument was that the family-related adversities were not truly external, and that genetic effects should have been considered. Read the whole thing here:
The corresponding author Michelle Kelly-Irving has kindly replied on behalf of all the authors, and I think it only fair to give this top billing as a separate item, so that subsequent comments can be appended as readers wish.
I don’t agree with you about the ACE measure being a proxy for parenting (or bad parenting). The measure aims to capture events that are likely to be stressful to a child, and that may have a permanent impact on their subsequent physiological reactions to stressful conditions. I agree that parenting is certainly implicated. However, should a child be separated from either parent through death or divorce is certainly not down to inadequate parenting. Similarly, a child who ends up in care is likely to be going through a stressful phase of their lives, but I’m not sure we can make the assumption about the parenting they received beforehand. It would make more sense to actually try to measure elements of parenting, which is certainly worth doing. There may be some variables in the NCDS that allow for this.
At age 11 any measure of IQ is hugely confounded with socioeconomic and psychosocial circumstances. I am not clear as to what IQ would be measuring here – or ever, in fact.
The point that a prior variable linked to both ACE and premature mortality that we do not know about, or cannot take into account, is of course possible. That variable could be a genetic one. Genetics analyses using GWAS are not coming up with solid explanation for heritable traits. It is most likely a much more complex process of heritability than a mendelian-style genetic one, if there is something going on heritability-wise.