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Taxi drivers rarely die of Alzheimer's

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Re: Taxi drivers rarely die of Alzheimer's

#241

Post by mapt »

nylonstrung wrote: post #233
jstummbillig wrote: post #218

Earlier quoted context omitted.

The comment insinuates that the study did not control for age. The study controlled for age. It's not terrible to not make a good point, but it's not a good point. The not good points should not be ranked highly.

It's getting hard to find any study posted without a kneejerk "correlation does not equal causation" take as if that's not something researchers have to control for in order to even conduct the study in the first place, let alone publish

The institutional media departments, journalists, and headline writers add back in the insinuated causation and effect size as a routine matter. That way we can't find fault with the researchers for their clickbait study.

Re: Taxi drivers rarely die of Alzheimer's

#242

Post by KaiserPro »

nojvek wrote: post #222
neuralkoi wrote: post #90

Earlier quoted context omitted.

They have to memorize 25,000 streets. The test is no joke. [0] [0] https://www.youtube.com/watch?v=ur61kzXjvN8

Test may be no joke. But the test is also a joke in the world of GPS and Uber. I am glad Uber plowed through various stupid regulations constraining supply to bring a service with drastically more supply.

> I am glad Uber plowed through various stupid regulations

What like safety checks?

London had a huge minicab system, which is very much not knowledge based. Addison lee also had internet booking of cabs way before uber, but with the advantage that cars were roadworthy and the drivers were safety vetted.

TFL came down hard on uber 1 for safety and 2 for clogging up the fucking roads and making busses slow. (see https://bsky.app/profile/garius.bsky.social for more info)

Re: Taxi drivers rarely die of Alzheimer's

#243

Post by KaiserPro »

inglor_cz wrote: post #72
genxy wrote: post #47

Earlier quoted context omitted.

People who would pass The Knowledge test might already develop dementia at a much lower rate.

Plausible, but then you'd expect to find the same effect in other people who passed similarly demanding tests once. For example in people who studied something geometry-heavy. Also, The Knowledge Test is, IIRC, passed only once and then you do not have to retake it for the rest of your career. If a test passed in your 20s or 30s predicted accurately a much lower incidence of Alzheimer's in your 60s, that would be a r…

The point of the test is that you know how to traverse london, and you also know and have a feel for patterns in traffic.

In the same way that you have code smell.

Granted, some use GPS, but most only really use it for pickup

Re: Taxi drivers rarely die of Alzheimer's

#244

Post by cma »

cma wrote: post #175
jollyllama wrote: post #154

Earlier quoted context omitted.

Or, that if you can survive the thing that kills the rest of their cohort, it has beneficial tradeoffs. As in, perhaps smoking protects from Alzheimer's, if it doesn't kill you first.

Controlling for age in a profession with a high fatality rate like this seems like controlling for high alertness, consciousness, quick reaction times, and well restedness/low stress, low recreational drug and alcohol use. Of those, sleep issues are highly correlated with Alzheimer's and also with auto accidents. Controlling for age alone here would select for low incidence of sleep issues.

*meant to say conscientiousness (keeping brakes, tires maintained), not consciousness

Re: Taxi drivers rarely die of Alzheimer's

#246

Post by Phemist »

wisty wrote: post #192
stymaar wrote: post #163

Earlier quoted context omitted.

It pains me to see such a low-effort contrarian comment at the top: as stated in TFA taxi drivers are below other profession when controlling for age, and there are multiple professions with lower life expectancy that still have significantly higher Alzheimer rate than taxi drivers.

A better low effort contrarian comment - isn't it that early symptoms appear less often with people with a "reserve"? Being mentally active (or physically active?) IIRC makes actual plaques both less likely, but also less detectable - a taxi driver can forget 90% of what they know and still not get diagnosed because they don't get lost on the way to the shops. Also they are often masters of small talk.

This would suggest they'd need to control for method by which the alzheimer's was discovered. A quick glance seems to indicate they did not do this. This is not information available I guess..

I would suspect this would eliminate a lot of the experiments participants, as only people who go for regular cognitive check-ups might be eligible?

I cannot imagine there would be many people left who'd be eligible. I can only think of 1 person that does it.. and he obviously does it for the pure satisfaction of acing those cognitive tests, and not because he is showing worrying amounts of decline in his mental faculties.

Re: Taxi drivers rarely die of Alzheimer's

#247

Post by lofaszvanitt »

cortic wrote: post #30

Taxi Drivers: The mean age at death is approximately 67.8 years. General Population: in the same dataset, life expectancy averaged 74 years. The average age at which patients are typically diagnosed with Alzheimer's disease is 79. People in these jobs don't live long enough on average to get diagnosed, at the same rate. The same effect will happen in any job that lowers your life expectancy.

Yepp, they die from circulation related illnesses. Since the sit all day long in the car.

Re: Taxi drivers rarely die of Alzheimer's

#248

Post by Noaidi »

I think this actually suffers from selection bias. To be a taxi driver in London is not just simply applying for for the job and trying it out. You have to pass a very difficult memory test to be a taxi driver in London.

So the study might be testing out people who have extremely good memories to begin with and might be less likely to suffer from Alzheimer’s genetically.

So I’m wondering if this would still be true if it was tested on taxi drivers in New York City.

But my other theory, if this is not true, is that because they are now seeing Alzheimer’s as being a problem of glucose transport , and Since using your memory uses energy in the brain, this would lower overall glucose in the brain and protect it from developing all Alzheimer’s.

Or maybe like I said before that these people who can pass these taxi driver test already have excellent glucose transport in the brain which enables them to memorize the streets of London so much easier.

Re: Taxi drivers rarely die of Alzheimer's

#249

Post by morelandjs »

stymaar wrote: post #163
cortic wrote: post #30

Taxi Drivers: The mean age at death is approximately 67.8 years. General Population: in the same dataset, life expectancy averaged 74 years. The average age at which patients are typically diagnosed with Alzheimer's disease is 79. People in these jobs don't live long enough on average to get diagnosed, at the same rate. The same effect will happen in any job that lowers your life expectancy.

It pains me to see such a low-effort contrarian comment at the top: as stated in TFA taxi drivers are below other profession when controlling for age, and there are multiple professions with lower life expectancy that still have significantly higher Alzheimer rate than taxi drivers.

Worth mentioning that controlling for confounders is hard, a reasonable prior is the null effect, and any time a researcher makes a mistake it produces a publication claiming a novel effect. You observe a set of publications concentrated with false positives as a form of selection bias. I wonder how many of the causal studies are reproduced by independent teams using independent datasets.

Plausible scenario. Individuals predisposed to Alzheimer’s experience different mental sharpness from birth and this makes them enjoy taxi driving less (more intense than long-haul trucking), and so they pursue taxi driving as a career at lower rates. Under this scenario, driving has no effect, it just induces a selection bias.

Re: Taxi drivers rarely die of Alzheimer's

#250

Post by Noaidi »

monster_truck wrote: post #95
genxy wrote: post #47

Earlier quoted context omitted.

People who would pass The Knowledge test might already develop dementia at a much lower rate.

They could also develop it at the exact same rate and mask it effectively. Had a very sharp family member who was completely lucid through all of dementia, it was like watching a tape rewind. Got to meet each decade's version of them over a couple of years. Towards the end they were completely normal

They could easily test for APOE genetics and see if people who carry the risk genes have a lower risk or are less likely to be London cab drivers
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