That's not what the source meta-analysis[0] says: "Our findings support an association between cat exposure and an increased risk of broadly defined schizophrenia-related disorders; however, the findings related to PLE as an outcome are mixed. There is a need for more high-quality studies in this field." (DOI: 10.1093/schbul/sbad168 linked at the bottom of the editorial)
On the contrary the epidemiological interpretation of the study's conclusion would be aligned with the chosen headline, for once.
"Kids with cats have double the risk of developing schizophrenia" seems to line up with the study's conclusion that "Our findings support an association between cat exposure and an increased risk of broadly defined schizophrenia-related disorders". The odds ratio is greater than 2 which translates into a doubling of the risk (eg odds) and >25 years is an excursion criteria. The lower bound CI is > 1 so it's likely to be a real association. PLE is Psychotic Like Experiences that seems to be a broader definition, which does not have a significant association. This can be due to lack of studies with said definition or imply that the effect is specific to schizophrenia-related disorders. However, the causality part is not investigated.
The more accurate title would say "schizophrenia-related disorders". Since cat-related schizoform disorders may be clinically distinct, this could be a useful distinction.
I wonder how this may have impacted world history. Something along the lines of humans have grain storage >> rats are attracted to grain >> cats are attracted to rats >> humans are attracted to cats >> human populations with cats become slightly more schizoaffective (which in most premodern societies is not really pathological) >> these societies commune with the divine more/tell the future/develop more complex religious institutions >> these religious institutions help stabilize society
From an evolutionary point of view I still think cats are the most successful animals. They have managed to get the ultimate apex predator (humans) to feed, care and provide shelter for them, in exchange for merely existing and looking cute.
> Dogs are generally better companions, but lots of people have dog-like cats that wanna be around them 24-7.
I guess it depends on how you define "better". We have cats who snuggle with us in bed at night, but mostly do their own thing during the day, aside from little spurts here and there where they'd like (but don't demand) some attention.
Meanwhile, most of my friends' dogs annoy the hell out of me. No, I don't want you to jump on me and slobber all over my face every time I see you. And most of my dog-parent friends agree that their dog requires a lot more attention and work than our cats do.
Any kind of companionship, even a mouse, can provide that kind of emotional support, but that says nothing of the animal's intent or ability to harm others. They are solitary creatures whereas dogs are social creatures. It's little wonder they would be carriers for parasites such as Toxoplasma gondii, whereas dogs aren't
If you ever watch the videos of the cats going outside with a camera, they almost always end up meeting up with other random neighborhood cats and interact and play. I don't think they're as solitary as people think.
We have a number in the house and they enjoy each other's company.
Just to expand upon what civilitty said: cats are solitary hunters, but live in social packs. They absolutely prefer to live socially if given the choice. Cats being solitary creatures is a myth.
Your rebuttal is also wrong, since cats do make decisions for the good of their colony.
In reality cats are man's best friend. Dogs are a child surrogate, except they never reach an age where they're independent. Which is probably half the appeal: they never outgrow us, unlike our children (or our cats).
I feel like we domesticated dogs and selectively bred them to follow commands and do what we want. For cats it's more like the other way around, they domesticated us and still have their complete independence.
Great point. I guess the 21st century will close out with at least an AI powered cat-dog, possibly a synthetic biological mutant cat-dog, possibly even a cyborg pet cat-dog with a brain internet interface for friend-foe identification, poisonous food identification, "I lost my pet", etc. Probably on a cloud license (you never really own your pet... all pets are the property of CloudCorp...)
Cats are not socially dependent animals. They are sole survivors. It makes perfect sense to me that cats would, like rodents, be common carriers of such diseases.
I honestly feel that the majority of the 'cats are anti-social' is due to them being in chaotic households. we've rescued a number of cats over the decades and no matter how antisocial the family claims they were before they got rid of them, after a year or so they are just cuttle bugs in our house, which is quiet and very consistent schedule wise.
To me cats are a lot like introvert-leaning ambivert people. They enjoy being social, but context and consent are important, and energy for socialization is not boundless.
Any kind of companionship, even a mouse, can provide that kind of emotional support, but that says nothing of the animal's intent or ability to harm others. They are solitary creatures whereas dogs are social creatures. It's little wonder they would be carriers for parasites such as Toxoplasma gondii, whereas dogs aren't
Lead plumbing pales in comparison to the lead they consumed via cooking pans (typically a lead / copper alloy) and a lot of Roman utensils used lead. Most tap water at room temperature won't absorb lead from pipes due to the mineral content and acidity. However, cooking in a pot made from lead will definitely poison you.
There's so much BS around toxoplasmosis online. Here's corrections for two common misconceptions:
1) Almost everyone who has it got it from eating undercooked meat, not from cats. France has the highest rate of toxoplasmosis in the world because of their propensity for rare meats: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5312802/.
2) Unless your cat lived a long part of it's life as an outdoor cat, it is very unlikely to have the parasite (like any parasite).
> The researchers conducted an extensive study search across various databases and gray literature from January 1, 1980, to May 30, 2023, without geographical or language limitations. They included studies reporting original data on cat ownership and schizophrenia-related outcomes. Out of 1,915 identified studies, 17 were used from 11 different countries.
cherry picking studies to find some meaningful signal. Meta analysis is not a thing, it's just pseudo-science.
It'd be easy to rule this out. Cats who have been indoor-only without access to rodents are unlikely to have it. This would be a good distinction to collect/analyze if wanting to add credibility to the toxoplasmosis theory and rule out other cat related factors.
That would still be hard to control for. I believe I recall reading that a T. gondii infection is something you get for life. Even if you adopt kittens from your local shelter at 8 weeks old, and then keep them indoors for the rest of their lives, they may have come in contact with rodents at some point before they made it to the shelter.
Hell, regardless of that, many homes in many places suffer rodent infestations at some point in time. Even if you get the exterminator in, it might be too late. This summer we bought a new house, and a few nights in, our (fully indoor) cat showed up to our bedroom, a (still breathing) mouse hanging from his mouth. So much for keeping him away from rodents.
The shedding of oocytes is how humans become infected. This is supposed to be stopped by the cats immune system a few weeks after initial infection. It is possible it could reoccur later if the cat's health changes as other life cycle stages exist in the cat.
I don't mean to judge, just an honest question: considering we're talking about indoor cats, how do you have plenty of rats inside your house? Is it something you can fix completely with professional services? It's what people usually do so I'm curious if it's a special case.
In my case, they lived in my neighbor’s unkempt yard and a few secluded spots from when the previous neighbor raised chickens. This summer, they moved out and the house was vacant for a month. First time in 20 years we found mice in our house. We did have them in our garage about 10 years ago until I changed some things.
Although I'm all for the study of T. gondii, they also state other factors that could affect schizophrenia outcome:
>> Environmental factors are also important. Epidemiologic studies, for example, have established that winter-spring birth, urban birth, and perinatal and postnatal infection are all risk factors for the disease developing in later life.
There's so much BS around toxoplasmosis online. And apparently in this article. Here's corrections for two common misconceptions:
1) Almost everyone who has it got it from eating undercooked meat, not from cats. France has the highest rate of toxoplasmosis in the world because of their propensity for rare meats: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5312802/.
2) Unless your cat lived a long part of it's life as an outdoor cat, it is very unlikely to have the parasite (like any parasite).
So I suspect toxoplasmosis is completely uninvolved in any correlation they may have found.
Hmm. My schizophrenic relative really likes cats. Could it just be a genetic predisposition to like cats is related to a genetic predisposition to the illness?
This just seems like a review of previous studies, picking and choosing evidence/previous conclusions from tangentially related investigations. I can’t access the published paper but the article implies this area has been studied before, so I’m confused what this new paper is supposed to contribute. Is it just a literature overview?
I’m interested in getting a cat in the future so I’m interested in a proper study of this.
The article subtitle is a "A Systematic Review and Meta-Analysis".
Many good refs define both but [1] is free. As far as how you might think of them [2,3] give context. The exact extent of merit can be debated but these do have merit.
Only somewhat related, but many of the comments highlight the importance of not using "rat" as shorthand for "rodent." Cats will happily sport-kill their way through mice, moles, and even rabbits, but they tend to leave rats alone because they are big and fight back.
I was thinking about this the other day as well, I wonder how much pet ownership in general also has a direct impact on fertility. Not fertility rates (as in, couples choosing not to have kids get pets instead), but rather toxoplasmosis effects. One counterpoint is that in previous decades, many families in certain western countries had some sort of pet but also had many children, but I wonder if living spaces becoming smaller (esp in cities) has amplified a minor effect.
Anecdotally (tiny sample size of course), we know several couples trying without success, but those without pets seem to get pregnant moreso than those with.
> This affinity may be related to the lack of a single enzyme in feline guts, delta-6-desaturase.
One route might be genetically engineering the introduction of the the gene(s) for this enzyme, if we can prove it reduces the infectiousness of the parasite.
<looks at previous comment's dv's> Fair enough, it is indeed a cruel world where our children can't even eat animal faeces in safety, and any levity to the contrary should indeed be harshly punished - thank-you-sir-may-I-please-have-another? <bares back>
Worth noting that the incidence of toxoplasmosis gondii in cats is heavily correlated with allowing them outside, which is where they usually contract it.
Surprise! If you let your animal outside and let it interact with, and even potentially consume, other wild animals, it may spread things!
This article draws conclusions only to support a clickbait title. There's no mention of the prevalence amongst cat cohorts. This is borderline fear mongering.
But don't simply listen to me, ask your vet.
Edit: would love to hear from down voters what about my comment they disagree with.
One of HN's special fixations is toxoplasmosis. Cats come up and there's a swarm of orange comments about how people like cats because they have a brain-control parasite.
Btw, that __medium article__ doesn't say "not true on intelligence," it says "orange cats aren't dumb" and doesn't cite any sources except its own blog. But if there's a systematic bias in male cats being more dumb then we have a confounding variable.
But I relied on a claim by an anthropologist who studies statistics. @clnq's citation notes a correlation with riskier behavior which I think many intelligence tests can codify as unintelligent. But wouldn't be surprised if it is wrong, but factuality isn't the point of the comment anyways. https://twitter.com/rlmcelreath/status/1696120557983425011
We usually have some appearance of a mouse once every couple of years. I suppose it’s possible others are getting in and being eaten by our cats or dog first, but that seems unlikely. Regardless, I believe cats which have eaten infected meat only shed oocytes for up to three weeks post-infection, and usually don’t shed again, so for most homeowners with indoor cats it’s probably a fairly low risk.
I believe gardening and playing around in dirt are both far more likely sources of toxoplasmosis infection anyway.
It depends where you live. Rats are less common outside the city. There are plenty of field mice and of course still some rats but they generally all stay outside as long as you've kept up with house maintenance.
We've had a few rats get into equipment outside our house over the years and probably a few (or squirrels) in the attic but to this date we've yet to see any evidence of one inside the house itself or anywhere the cats could get to them.
In the limited (but probably dominant, here at HN) context of middle-class-ish urban dwellers, I daresay there would be a sizeable proportion of clean, well-sealed modern homes in which rat ingress is at, or almost, zero.
Doubtless there is also a significant proportion of homes where rat ingress is more common.
But I couldn't begin to speculate about where those numbers might actually fall.
I am not aware of any testing that has approved vitamin B3 (niacin) as a treatment for schizophrenia. Perhaps you are thinking of vitamin B13.
At one time orotic acid was known as vitamin B13. It is no longer considered a vitamin. It is interesting that orotic acid can combine with lithium to form lithium orotate and some people believe it could be used as a treatment.
Lithium (carbonate) is sometimes used for the treatment of schizophrenia and although lithium orotate can also provide lithium, it has not passed testing for approval in any medical treatment that I have encountered.
[0]: https://academic.oup.com/schizophreniabulletin/advance-artic...