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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.
And how would you control for the causal possibility that those who will eventually develop Alzheimer's early on might tend to have undetectable memory issues that prevent them from becoming taxi drivers in the first place? You can't control for profession, since that's behind the very claim itself.
As the paper points out that's accounted for in the analysis, because shockingly enough to most internet commentators researchers know that they need to control for confounding variables
The study accounts for that.
Delay your aging by using your brain a fuck ton, all the time, learning brand new things nowhere near anything you already know.
From the article:
> After adjusting for age, sex, race, ethnicity and education, roughly 1 in 100 taxi and ambulance drivers died of Alzheimer’s, compared with 1 in 60 people overall.
| After adjusting for age, sex, race, ethnicity and education, roughly 1 in 100 taxi and ambulance drivers died of Alzheimer’s, compared with 1 in 60 people overall.
They claim to control for these factors in the 5th paragraph of the article here. Which is a standard thing to do in these kind of studies.
So you're point is either not relevant or that they didn't control for age correctly?
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.
Studies typically use regression to account for stuff like that. CBA to look at the article, but I bet any money that's controlled for.
Yep. Free solo climbers also rarely die of Alzheimer’s.
> In one landmark 2000 study, neuroscientists compared the brains of licensed London taxi drivers with those of people who did not drive cabs.
Location is very important here. London cabbies have to pass The Knowledge which is an extremely difficult memory exam that only people with particular kind of brain can do.
I wonder how it will look when we start doing statistics on gamers, if AI doesn't destroy our brains first. Then it would be interesting to plot the different death by genre like for example strategy, FPS, puzzle, etc. Someone else asked about Chess players which is probably also related right.
My grandad essentially died of alzheimers and he just loved to sit and watch football all day where you don't really need to think much.
I find the title highly misleading. The actual claim is a 40% lower chance (1 in 100 as opposed to 1 in 60) for taxi and ambulance drivers when compared to the average.
That’s a big drop but the title implies that Alzheimer’s is rare in taxi drivers specifically and I don’t think the difference warrants that claim whatsoever.
Could it be that the cause/effect relationship here is incorrect? Perhaps only people with the cognitive skills for complex mental maps and spatial reasoning can be effective at driving a cab, so driving a cab may not "protect" you from Alzheimer's at all, but people who have the skills to keep a job as a cab driver have a brain that is less susceptible to Alzheimer's.
The ones that do stopped being taxi drivers.
Related:
Alzheimer's disease mortality among taxi and ambulance drivers (2024)
229 points, 4 months ago, 137 comments
https://news.ycombinator.com/item?id=47559481
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Taxi drivers offer a clue to Alzheimer's risk
127 points, Dec 2024, 109 comments
https://news.ycombinator.com/item?id=42502899
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Alzheimer's Mortality Lowest for Taxi, Ambulance Drivers
12 points, Dec 2024, 9 comments
Something with more data:
When the original paper came out a few months ago, I vibe coded a quick reconstruction of the main results. Page has the interactive charts:
https://suvakov.github.io/vibes/AlzheimerMortalityByOccupati...
One of the first things to go with Alzheimer's is spacial mapping in the brain so this makes sense. Your exercising daily a part of the brain that is involved.
In addition there's the social component of driving - you may not always want to talk to a Taxi driver but many people do. And ambulance drivers are often socializing with their colleagues
Driving also has a mix of reaction time based skills and hand eye and hand foot coordination. Overall it's pretty complicated.
Writing this I'm realising the final "Turing" test for AI might actually be just replacing the average Taxi driver. Can it drive a car, choose a route dynamically based on day and traffic and weather, and have a conversation with a wide variety of people and topics all at the same time ?
I think in the future more cases of Alzheimer's are gonna be present
e.g with the potent use of marijuana that's present these days, excess drinking & lack of reading + dumbing down of population via use of llms.
I wonder if the usage of mobile navigation will increase Alzheimers for our generations.
When driving I either now the way or use maps, there is rarely any guesswork or active thinking involved, maybe running is helping but even there I sometimes run routes navigated by watch.
Something interesting that the original study looked at, but isn't mentioned in the linked article: this effect was not observed for non-Alzheimer's dementia deaths. There seems to be something specific to spatial reasoning and Alzheimer's.
> Risk adjusted percentages and mortality odds ratios were adjusted for age at death, sex, race, ethnic group, and educational attainment using logistic regression.
Adjusting for educational attainment is an intriguing choice. If higher educational attainment were to decrease risk of Alzheimer's disease, wouldn't this adjustment optimise out the factor that they're looking for?
Otherwise very interesting results and conclusions. Also what's up with the outlying occupation on the left side of the 1st 2 charts on page 3: "Personal care and service workers, all other" with a mean age of death of 50.65?
Accidentally stumbled on an ESRI's GIS for Scienece volume... there was a cited evidence of MRI scans of high-scholers brains, monitored while kids develop spatial reasoning skills. Well the images definitely showed prefrontal cortex better developed, only after an year. So this is more than anecdotal evidence.
Seems strange to me that a specific type of thinking could influence something where most causes being investigated are physical
Taxi drivers in old days needs to remember the whole map of their city, I think that is an efficient exercising/training that recommended for anti-Alzheimer, just like playing puzzles or quiz for oldman? But nowadays it is all about google map, not so sure about the effectiveness.
People who are likely to get Alzheimer's don't get jobs as taxi drivers.
> 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.
My grandfather was a taxi driver and delivery driver for many years. He made it to 93 and I don't recall him dealing with any cognitive decline. He used to tell me different routes to get to a stadium that was closed before I was even born.
Taxi driver also live shorter lives than average, which would fit with lower levels of alzheimers. But interesting link nonetheless.
This is a case where the claim is clearly nonsense, and the interesting question is where is the error.
I wonder if alcohol consumption plays a role here, since it is a known risk factor for Alzheimer’s. A taxi driver who works 60 hours a week will have very little time left over for drinking, whereas pilots have relatively short work hours where they actually need to be sober.
I had to read this a few times to make sure I read it right
> After adjusting for age, sex, race, ethnicity and education, roughly 1 in 100 taxi and ambulance drivers died of Alzheimer’s, compared with 1 in 60 people overall
I would’ve thought the effects were more profound
> rarely
> roughly 1 in 100 compared with 1 in 60
I guess the broad population also rarely dies of Alzheimer’s?
The overall dataset was very large (8,972,221 deaths), but only 1,348 ambulance drivers were included, and just 10 had Alzheimer’s disease as the underlying cause of death.
Such a small number of outcomes matter because statistical precision depends on the number of relevant events. With only 10 Alzheimer’s deaths, even a small change in the count could substantially alter the estimated association.
Taxi drivers provided more robust data, with 171 Alzheimer’s deaths among 16,658 decedents, but death-certificate Alzheimer’s mortality may not reflect how often taxi drivers develop the disease. Differences in diagnosis or cause-of-death reporting across occupations could influence the observed association.
The large overall sample does not eliminate uncertainty in the much smaller occupational subgroups, particularly among ambulance drivers.
Nonetheless, this is an interesting study and merits further investigation.
IF the key is spatial navigation processing. Would bicycling be included?
When in my car, I'm just dumbly following the map app. But on a bike, I'm still having to keep track of where I'm going and a route.
I wonder if the same is also true of other high-spatial-complexity activities like rock climbing and professional dancing? (Exercise level would of course be a counfounding varable to be eliminated in these cases.)
First rule of attentioneering
- If it bleeds, it ledes
Second rule - Got edge case? Got headline!
Can video games provide similar benefits?
Wasn't there some an article/video from somewhere where a man had worked in a hot environment (I think it was on a navy ship in the engine room) and even though his family had a history of Alzheimer's, he never showed any signs of it. Does anyone know what I'm talking about? (Might not be Alzheimer, might be thinking of another disease)
Then this should stand true for gamers who play a lot of open world games too...
might want to look into statistics on ppl who play a lot of first-person shooting games. does it have to navigation of physical environments? or virtuals ones work too?
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.
older taxi drivers from the past I guess, these days the modern taxi drivers are almost all GPS reliant.
Eating eggs actually lowers the risk of Alzheimers.
Any studies on chess player and Alzheimer's?
Does gaming also use similar spatial skills?
How many elderly Taxi drivers die of traffic accident? Perhaps the job is culling the Alzheimer's sufferers before other symptoms and signs arise?