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Taxi drivers rarely die of Alzheimer's

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Re: Taxi drivers rarely die of Alzheimer's

#271

Post by geysersam »

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.

So many possibilities for error...

Is every case of dementia diagnosed accurately? Is there a difference between professions how likely their dementia is to be diagnosed accurately?

Is there a correlation between dying early and being pre-disposed to have developed Alzheimer if having lived longer? If there is, then the "correction" for age is not correct, because the correction assumes the fraction of the group that died early were equally likely as the rest of the group to develop the disease if they had not died early.

I don't know anything about Alzheimer but it doesn't seem unthinkable that the factors that cause people to die early also could also play a role in causing Alzheimer.

Re: Taxi drivers rarely die of Alzheimer's

#272

Post by ausbah »

david-gpu wrote: post #49
cobertos wrote: post #22

Earlier quoted context omitted.

True, though the article does also mention another study not based on taxi drivers, but just living in high spatial complexity ZIP codes puts you at a lower risk. > Research on cognitive maps points toward the same conclusion as the study on taxi drivers. In 2023, researchers ran a machine learning model on more than 22,500 people in a national dataset and were able to predict which ZIP codes had higher rates of Alzh…

A dense street network with complex intersections also means living in walkable urban cores vs car-centric suburbs.

idk have you ever driven in boston?

Re: Taxi drivers rarely die of Alzheimer's

#273

Post by aetherson »

geysersam wrote: post #271
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.

So many possibilities for error... Is every case of dementia diagnosed accurately? Is there a difference between professions how likely their dementia is to be diagnosed accurately? Is there a correlation between dying early and being pre-disposed to have developed Alzheimer if having lived longer? If there is, then the "correction" for age is not correct, because the correction assumes the fraction of the group that…

You could imagine that pre-diagnosis confusion relating to Alzheimer's increases the risk of traffic accident and kills taxi drivers, too. Might not operate for truckers as much because they're more likely to survive accidents.

Re: Taxi drivers rarely die of Alzheimer's

#274

Post by monster_truck »

fluoridation wrote: post #201
monster_truck wrote: post #95

Earlier quoted context omitted.

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

I don't understand. Do you mean they were lucid, but they believed they were living in a different year? Like thinking adults were still children in school and wondering when dead people were going to call? That kind of thing?

More like literally rewinding through the decades. The 80s, 70s, 60s versions of him. The printing company CEO shaking my hand calling me Mr Monstertruck, the kid who just signed up for the marines wanting me to try on his fatigues because they didn't fit him right anymore but were perfect for me.

Stuff like "I'm your grandson, dadsnames kid" didn't parse at all, they said not to bring up shit like that so we didn't.

We had to move him into a house because he kept using his POW training to break out of the dementia ward. Pickpocketing keycards and shit, he was a badass till the end.

Re: Taxi drivers rarely die of Alzheimer's

#275

Post by monster_truck »

codygman wrote: post #167
monster_truck wrote: post #95

Earlier quoted context omitted.

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

So towards the end it was like it went away?!

Kind of, you could tell it took a lot of effort. Usually after a full night of sleep and a good breakfast, or after a nap. A few of us had lengthy car rides where he said everything he wanted to

He told me he was so jealous of all this new computer stuff I get to play with. I think about that a lot this year

Re: Taxi drivers rarely die of Alzheimer's

#276

Post by bluGill »

RIMR wrote: post #268
roenxi wrote: post #227

Earlier quoted context omitted.

But after the study controls for age the starkness of the effect more or less disappears (eyeballing Fig 1, the 2nd graph). It turns out that there is a profession with a lowest risk of getting Alzheimer's (duh, one had to exist) and it looks like a slight outlier (it's the lowest, we'd expect that one to look like a slight outlier). As outliers go it isn't that impressive, it looks like it is part of a fairly boring…

> But after the study controls for age the starkness of the effect more or less disappears (eyeballing Fig 1, the 2nd graph). Adjusting for age, Alzheimers deaths were 1/100 for taxi drivers, and 1/60 for the general public. That's extremely significant. However you feel about the graphs means nothing compared to the actual numbers presented here. > I'm sure it is a great study. Lots of science done. They do good gra…

> That's extremely significant.

What makes you think that is significant at all? Anytime you take a lot of small subsets of a large random sample you expect to find outliers that look a lot like this.

That is https://xkcd.com/882/ seems to better fix the data just as well.

Re: Taxi drivers rarely die of Alzheimer's

#277

Post by marcosdumay »

zarzavat wrote: post #226
roenxi wrote: post #211

Earlier quoted context omitted.

Fella has read the article, has an argument and some stats. What more do you want from a comment? He isn't running a study. Besides, the point is a good one. There are a lot of professions. If we glance at the underlying study [0] Figure 1 suggests that we'd probably expect to see an outlier or two in that mess just through chance, we're expecting a few p [0] https://www.bmj.com/content/387/bmj-2024-082194

A distinction is that Alzheimer's is in an uncommon category of mystery diseases. If a study found people who swim regularly are are less likely to get heart disease, that wouldn't be very surprising because know a lot about why people get heart disease. Therefore it would be valid to insist on more rigour for accepting (swimming => less heart disease) because the only use of that information is for health advice. Ho…

It's worth publication and awareness within people studying Alzheimer.

It's absolutely not worth publication with clickbait title and distorted description to the general public.

Re: Taxi drivers rarely die of Alzheimer's

#278

Post by bluGill »

brandonmenc wrote: post #107
coldtea wrote: post #61

Earlier quoted context omitted.

Ah, the typical cheap HN reaction to a paper, along with "correlation is not causation", and as usual, for things already factored in into it.

Hilarious, because accounting for this stuff is drilled into your head when you study the softer sciences (like psychology) even as an undergrad.

A large part of accounting is knowledge that we cannot control for it.

Re: Taxi drivers rarely die of Alzheimer's

#279

Post by vitiral »

> These findings stopped me in my tracks because those two jobs rely on the same thing as my own work: maps.

Those jobs rely on navigation, not maps. Reading maps and navigating the real world are very, very different things.

The later point about zip codes with higher complexity is the same - these residents have to _navigate_ in more complex situations. How the author seems to be conflating that their personal job of staring at maps therefore protects them from Alheimers is very wishful thinking IMO.

Based on this data, I wouldn't be surprised if Google Maps has lead to a rise of Alzheimers.

Re: Taxi drivers rarely die of Alzheimer's

#280

Post by dekhn »

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.

The first question you ask when you read a paper like this is whether you think the authors actually did control for what they say they controlled for. Usually, they didn't.
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