It has been said that schizophrenia strikes without regard to sex, race, social class, or culture. Whoever said that must be crazy: it’s far from true. Schizophrenia is more common in men than women – about 1.4 to 1. It’s more common in the lowest SES groups, although that may be downward drift. Schizophrenia is considerably more common among people of African ancestry. In the US, about 3 times more common. It seems that immigrants are more vulnerable, all else equal: that might be because crazy people are more likely to pull up stakes, or maybe being a stranger and afraid in a world you never made is bad for your mental health. Schizophrenia seems to be more common among people that grew up in cities – about twice as common. If we took this risk as seriously as teeny-tiny / uncertain dietary cancer risks, the freeways tomorrow morning would be clogged with frantic refugees fleeing the caves of steel.
African immigrants to Europe and Great Britain are much more vulnerable to schizophrenia. In the UK, blacks (from the Caribbean) have a seven to ten-fold increased risk. Interestingly, this actually seems to get worse in the second generation.
This would be more interesting if schizophrenia was a natural category, easy to definitively diagnose. There’s something there, surely, but clean-cut it’s not. There is reason to suspect that people researching mental illness are crazier than average: this hasn’t helped.
Many – most! – of the articles addressing the higher rate of diagnosed schizophrenia among blacks attribute it to clinician bias. Jonathan Metzl has written a whole book on this thesis: The Protest Psychosis. Judging from those high rates in Afro-Caribbeans (as much as 15 times higher !) British psychiatrists must be the world’s most rabid rednecks. They probably begin therapy by making the patient squeal like a pig. But psychiatrists in the US must be highly racist as well. Somehow this has escaped the stereotype factory: that isn’t the way psychiatrists portrayed on the big screen. It’s more about eating someone’s liver “with some fava beans and a nice Chianti”, or stalking Capucine.
If we understood mental illness better, these epidemiological patterns would probably be telling us something interesting.. As it is, I’m not sure.
West Hunter 
Schizophrenia is probably disappearing
http://davidhealy.org/the-madness-of-young-people/
Are there places which still use or haven’t yet removed all their lead piping?
Are there other things which have the same effect as lead?
The Times had an op-ed today on treating schizophrenia, how the voices differ in India vs. the U.S., and how the Europeans do it so much better than Americans, and speculation on why American schizos are so much more violent, with the usual suspects rounded up.
I got a particular kick out of this take on America’s bad influence on the mentally ill from a commenter:
Americans think in violent terms: killing, shooting, beating, bombing when confronted by conflict. Believe it or not, many other cultures address conflict not with aggression but with the assumption that an offending party will listen to the aggrieved and work together for an amicable solution…From demonizing unions to backing coups to lying about science to funding warlords to propping up dictators to bombing peasants, to the glorification of war to mongering fear of communists, subversives, people of color, immigrants and terrorists, there is a constant drumbeat of threats and violence as the solution to threats in the USA.
You’d be shocked to learn that nothing along the lines of what you said here was discussed.
And of course, unions, communists, people of color, immigrants, and terrorists are all totally peaceful, and this is why the US has such a terrible record of mass murder when compared to Russia, Germany, China, Congo, and Mexico…
You just can’t make this stuff up.
I can confirm from 40 years of working with British psychiatrists that they are not red-necks. They include the more thoughtful and humane of doctors. So much so, that they often place the “de-stimatisation” missionary campaign well in advance of the “actuary” position. See “Schizophrenia and violence: delusional numbers”
“http://drjamesthompson.blogspot.co.uk/2013/03/schizophrenia-and-violence-delusional.html
So thoughtful and human that they lie like a rug.
My anecdotal evidence does agree with schizophrenia being more common in Blacks, particularly Caribbean Blacks…
Quoting Kevin Mitchell: “No need to wonder in ignorance – maybe reading some of the extensive literature on the subject would help”.
So many strawmen you could breed horses on this blog.
You beat me to it! 🙂
So many strawmen you could breed horses on this blog.
Are you suggesting that the author is raising lots of strawmen?
I don’t see any strawmen, just politically unacceptable truths.
People are taught to blurt out “strawman,strawman!” without further argument when they encounter thoughtcrime. Defense mechanism.
Major criteria for schizophrenia are hallucination and delusion. When people have too much imaginations, these people are vulnerable to be diagnosed as schizophrenia. Also people of lower IQ have hard time differenciating fact from opinion or imagination.
People of different idelogy can be easily labeled as `crazy’
Religious idelogy can also be traced as some kind of hallucination or delusion when miracles happened.
On the other hand, super smart people not understandable for common people can also be labeled as crazy such as Galileo.
anybody that has worked with schizophrenics knows it’s not simply “they have too much imagination” or “lower IQ” etc. they hear voices, mainly bad voices (only once in 10 years i worked with one whose voices told him “jokes” & he was often smiling & twirling a nonexistent moustache). schizophrenic behavior is qualitatively different from normal – especially after their first psychotic break, they are NOT normal people mistaken for crazy people (& saying “ah, but what is normal?” does not mean there are no schizophrenics) work with some adult schizophrenics for a while & see what you think then! & the rate of schizophrenia is higher in males, blacks, poor, etc. their life span is much shorter than average. it is not a pretty thing & it is not a simple case of misunderstanding an imaginative person who thinks differently.
As practicing physician, I know how to make clear clinical diagnosis with things you mentioned. But I did have a female patient who believe she can see and talk to `God’ directly. I admitted that I can not handle this `patient’. So I send her to referrals.
I don’t think the anti-psychiatry movement of the 1960s was correct, but I think they asked some important questions about how doctors declare people sane or mad.
The diagnosis of mental illness has often been used dishonestly, notably in the old USSR, but also in the West. For instance, Ezra Pound was not mentally ill in a clinical sense; but declaring him insane got him off a treason charge. Similarly, when the relatives of a millionaire get cut out of his will, they can always find a psychologist to testify that he was not of sound mind, even though the psychologist never met him.
Thomas Szasz grasps the issues far more clearly than R.D. Laing or Michel Foucault. For Szasz, mental illness must be physical illness – like Alzheimer’s disease or CJD, rooted in the plumbing of the brain. Otherwise psychiatric diagnosis easily becomes a disguised moral judgement posing as objective medicine.
What we need for Schizophrenia is an objective test to confirm what patient interviews suggest.For instance specific signs shown by neuroimaging.
Are we anywhere near this yet?
Thank you. I have been doing this for 35 years and you are essentially correct panjoomby. It is easy to find exceptions, but your summary should be the take-away. There are some interesting additions. Young males have a 2x schizophrenia rate, but there is a slow-developing category of some similar thought disorder which is much more common in females. Because mood-stabilising medications seem to be necessary, even when overt symptoms of affective disorders are not prominent, there was considerable opinion that this illness, often called schizoaffective by default, is something different. We are no longer allowed to say that out loud, except to other older clinicians who remember.
Also, sexual identity questions are much more common in schizophrenia – and we can’t notice that either.
Even physicians aren’t allowed to notice certain things? I’m surprised, and a bit dismayed. John Derbyshire somewhere notes that we seem to be slipping into the mode of the Confucian “superior man”–“superiority”, in our civilization, means not noticing the characteristics associated with sex and race. I would much rather that we slip into the mode of the Nietzschian man–to find truth by looking cynically.
Was Julian Jaynes right?
Not remotely. Next.
You’ve written a lot on paternal age and the accumulation of mutations. Any reaction to this?
http://blogs.discovermagazine.com/gnxp/2013/09/older-fathers-and-the-iq-of-their-children/#.UjycWGRT0kg
Thanks. Excellent paper it seems with a very impressive literature review. Not such a large sample size but IMHO anything that requires a larger sample size to show up probably is not very important.
I hope the study is wrong somehow as the load theory has a lot of politically incorrect explanatory power that would be very unpopular in PC circles and thus entertaining to watch.
The study needn’t to be wrong for you to be satisfied. The difference between 40 and 50 denovo SNPs between a younger and older dad may prove only modestly retarding, while a load difference of thousands of SNPs between smart person a and less smart person b may be more powerful. A GWAS of genome-wide load and IQ is where your support mojo might be profitably invested.
The per-generation load difference between old and young dads is on the order of handfuls of (hotspotty) SNPs, and should be expected to be modest, until it reaches the scale of many generations. I suspect that the people doing the study were smart enough to expect the per-generation effect to be small, they don’t seem very surprised at their statistically insignificant r.
Again I learn something new. I’ve reblogged it here:
http://ex-army.blogspot.com/2013/09/insane-equality.html
“Schizophrenia seems to be more common among people that grew up in cities – about twice as common.”
Schizophrenia, homosexuality, I’m sure we could come up with some other pathological behaviors that are more common among people that grow up in urban areas.
Maybe modern cities verge on the behavioral sink and some people are more resistant to the damaging mental effects of this environment than others.
Africans in the West would have less resistance because of their lesser history of urbanization. They suffer from higher rates of homosexuality as well.
http://www.cabinetmagazine.org/issues/42/wiles.php
Lots of close contact in cities versus rural or less populated areas. Lots of germs and probably more toxins as well.
There is actually not much hard evidence of Blacks having higher rates of homosexuality, as noted by Jayman, Rushton, and Misdreavus. Self-report studies don’t really count due to there inconsistent results.
(REFS: Remafedi, Resnic Blum and Harris (1992) Demography of sexual orientation in adolescents. Pediatrics. 1992 Apr;89(4 Pt 2):714-21; Remafedi, Resnic Blum and Harris (1992) Demography of sexual orientation in adolescents. Pediatrics. 1992 Apr;89(4 Pt 2):714-21; Krieger and Sidney (1997) Prevalence and health implications of anti-gay discrimination. Int J Health Serv. 1997;27(1):157-76; Rust 2000, Bisexuality in the United States; Krieger and Sidney (1997) Prevalence and health implications of anti-gay discrimination. Int J Health Serv. 1997;27(1):157-76. Belkin and Bateman 2003. Don’t Ask, Don’t Tell: Debating the Gay Ban in the Military)
Schizophrenia is higher among people of African descent living in England? It sounds like it has something to do with vitamin D.
Two things worth thinking about:
1) The Caribbean was the site of the most profitable slave-using agriculture (sugar). As a consequence, the islands got the most coveted slaves, from the Gold Coast, while the tobacco colonies in what is now the US got the least desirable–from the Niger delta. So one reasonable test of this would be to see whether schizophrenia is unusually high in Ghana.
2) Cannabis use is said to correlate with very high probabilities of becoming schizophrenic (10-fold, I think, and I think also this was something published in The Lancet, so it relates to British populations). Perhaps Caribbean origin conflates two things: cannabis use and West African heritage.
I’ve always thought Number 2 was possible. However over the last 40 years the gap in cannabis use between black and white narrowed (at least in urban areas) so if cannabis was one of the causes the number of white schizophrenics should have gone up. I don’t know if it has or not.
The gap between *very heavy* cannabis use among black and white urban working class was huge in the 70s.
Also if there’s a cannabis connection then rastafarians should be out ahead of everyone.
@ghazi-less. Regarding cannabis, it is hard to ferret out the full story just yet, but there is some connection. As marijuana is very good at reducing anxiety short-term, it is hard to see which way the causal arrow is going. Marijuana in America isn’t uh, standardised, so there tend to be other complicating ingredients, plus a likelihood that other substances of abuse are in play. Still, the connection to mariijuana in specific has been noted for years and recently some harder numbers do indicate that if you have genetic vulnerability, THC is a particular activator. Yet we have all known people who were permanently baked in their 20’s yet show no psychotic symptoms in their 30’s.
If you have any blood relatives who have a psychotic disorder, you should be staying far away from marijuana.
And then there’s cat poop…
Was Aaron Alexis the spark for this article?
A little, not a lot. I’ve been pondering the high black schiz rate for quite a while.
How about the high irish schiz rate?
If the schizophrenia rate is high in Ireland, that’s consistent with the vitamin D hypothesis.
Assuming that sub-Saharan Africans with an average of 70 iq act ”normally”, while for most of the Eurasians this range iq act according to their degree of mental retardation, so I believe that any assessment of the behavior of Sub-saharan africans should be analyzed separately. I always had the impression that mood disorders were more common among whites than among blacks.
If this guy was not taking medications them to control their alleged esquizofenia, then someone could explain to me how he managed to travel to Thailand and live there?? People with schizophrenia, rather than mood disorders, tend to be very dependent on their family and in my opinion, could hardly do this kind of long trip.
Living with people of low IQ, I have observed that the lack of responsibility is similar to psychopathic behavior and therefore these people may present more of this type of behavior than people with average intelligence and above.
Concluded that as a humanist perspective, nature is psychopathic, so the closer the animal kingdom, an individual is, the more it will tend to be psychopathic.
Of course, I speak of averages.
PBS says that the more important question is the Psychological harm of inequality.
MHC
aoeusnth2002,
First psychotic breaks are more common in the summer than any other season. That points away from vitamin D and towards folate. I would be interested in seeing schiz rates for people who are very light/dark for where they live. Eskimos and Australian whites come to mind.
I wonder about the schiz m/f ratio. Borderline personality looks like a psychotic disorder to me.
IIRC, there was a small study that found a positive correlation between positive shiz symptoms and number of sexual partners, and a negative correlation between negative symptoms and sex partners. I don’t remember it well. They might have looked a schizoid and schizotypal personality. It would be interesting to see if black schizophrenics have more/more severe positive symptoms. Wonder about female farming societies other places. With evidence accumulating that shiz and autism are inverse disorders, one might be tempted to speculate that schizophrenia is a pathological extreme of the interpersonal mind.
Do schizophrenics have lower IQ scores than one would predict from parents and siblings, or is it just that children of lower IQ parents are more likely to go crazy?
Almost married a borderline and have a schizophrenic brother, both with very high IQs. I can attest that the resultant behaviors often look very similar.
Statement 1-
“Schizophrenia is considerably more common among people of African ancestry. In the US, about 3 times more common. ”
statement 2-
“Judging from those high rates in Afro-Caribbeans (as much as 15 times higher !)”
Either one of these numbers of completely wrong or the cultural explanation for schizophrenia is starting to look like a good one.
I guess that afro-carribeans have less non african admixture than african americans, but still, can that difference be responsible for a 5 times lower rate of schizophrenia in african americans?
I’m trying to figure out how my healthy, athletic, business-owning 27 year old brother made it, in six months, to calling 911 and giving a graphic description of a jet airplane being shot down over Puget Sound. Or that he filled tens of thousands of lines in journals with exactly 4 words of gibberish while managing to carefully document that gibberish to the hour and second. He would write the same line about ten lines and then change one word, then write that same sequence around ten times. Clearly, the content of his psychosis was culturally informed but I find the position that holds culture the cause of the onset to be pretty dubious.
There may be something in the environment that is some sort of trigger that interferes with organic brain function that is especially common among afro-carribeans. Who knows.
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redzengenoist
“The per-generation load difference between old and young dads is on the order of handfuls of (hotspotty) SNPs, and should be expected to be modest”
Sure, for load to have no major effect over large numbers of individuals over multiple generations there would need to be zero effect or close to it on an individual level but that’s what they seem to be saying unless i missed something?
(which is quite possible)
No, I think you understand it correctly.
Sure, the current “no major effect” outcome for small n, 1 generation is consistent with both:
1. no effect on plural generations, it’s a dead end, and
2. big effect on plural generations, defining of idiocy and genius in human history, single greatest mutational effect in the history of genetics, TED talks for prospective dads, etc.
It’s just impossible to tell which, from this type of study. Too small, too noisy design.
I think we’ll find more reliable clues, not from bigger, better, multigenerational longitudinals on more generations, but from directly measuring the mutational load, with WGS. 10 or 20 SNPs between young/old dads is just too small, the “crud” of human bio-noise will dominate the signal.
Directly measuring 1000’s or 10’s of 1000’s of SNPs, however… even associating for loci, so you can count more efficiently… that has power and utility.
ty
Though its obvious to me that schizophrenia is a disease of sorts, I can’t help but wonder about whether schizotypalism (mild schizophrenia) may have been under positive selection in the evolutionary past as linked to shamanism and its precedents, and therefore not an illness. Maybe I’ll write more about this when I’m out of this hospital (no, it isn’t a mental hospital.)
I think you would find this to be of interest: http://www.psychologytoday.com/files/attachments/95822/schizophrenia-and-sexual-selection.pdf
Thank you.
Here is a case of low IQ associated delusion/hallucination.
http://www.nydailynews.com/news/national/woman-pleads-guilty-telepathic-rape-case-article-1.1467002
Of mice and schizophrenia
Toxoplasma also appears to be involved in the initiation of more severe forms of schizophrenia. At least 40 studies confirmed an increased prevalence of toxoplasmosis among schizophrenic patients. Toxoplasma-infected schizophrenic patients differ from Toxoplasma-free schizophrenic patients by brain anatomy and by a higher intensity of the positive symptoms of the disease.
Is there a similar increase in Australian aborigines, New Guineans & Maoris?
I’m thinking that if this is something which mainly appears in urban situations, as is the case, or perhaps is not much of a problem in tribal ones then schizophrenia may only have become evolutionarily disadvantageous when we ceased being tribal. When being hunted by sabretooth tigers being paranoid may be an advantage. In which case it will be much more common among peoples who have not been long urbanised.
Schizophrenia hallucinations may also account for the regular appearance of gods/demons in quite matter of fact histories.
Greg elsewhere you wondered whether ancient Greeks were smarter than the average Persian. Perhaps they had just been urbanised longer. Greek culture’s treatment of their gods tended to be more metaphorical as if they weren’t actually seeing them. This would also account for them having no genetic edge now – everybody else has caught up.
Seems to make sense. Psychosis (schizophrenia) = excessive dopamine in some brain areas, which is why antipsychotics block dopamine, while levodopa, the dopamine replacement drug used in Parkinson’s, can produce psychosis.
Low Dopamine in emotional circuits = amotivation and lethargy and depression.
Blacks = cheerful, outgoing, gregarious (even Charles Darwin said so)
Possibly blacks have naturally higher dopamine levels.
This may also correlate with higher testosterone. Blacks have higher testosterone than whites, and men have higher testosterone than women. If schizophrenia rates are higher in both these populations, then testosterone, dopamine and schizophrenia are possibly all connected.
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Well, here’s one study on the matter. A huge population-based longitudinal study from Sweden with a combined N > 2.3 finds – using sibling and cousin controls – that the urban effect on schizophrenia incidence is entirely due to self-assortment. Family members discordant for residence weren’t any different in their schizophrenia incidence – nor for depression for that matter.
Does Population Density and Neighborhood Deprivation Predict Schizophrenia? A Nationwide Swedish Family-Based Study of 2.4 Million Individuals
Incidentally, they found that those born in the 1960s and 1970s are at higher risk for schizophrenia, though not for depression. This seems to be similar to findings in the States. I wonder what’s up with that…
So here’s another paper you might like. A million-man draftee study out of Sweden has found schizophrenia to be inversely associated with IQ. This holds even between MZ twins.
IQ and Schizophrenia in a Swedish National Sample: Their Causal Relationship and the Interaction of IQ With Genetic Risk
This indicates some “environmental” factor must be driving much of this relationship. Since the shared environment impact on schiz is 0, only a handful of things fit the bill, like developmental noise or pathogens. Can low IQ be partly caused by pathogens, then?
Is this perhaps linked to lack of vitamin D amongst blacks in northern latitudes?