PDA

View Full Version : Salyut 7 Cosmonaut says spaceflight gave him cataracts



matthewota
2008-Dec-25, 05:20 AM
http://www.examiner.com/x-504-Space-News-Examiner~y2008m12d20-Cosmonaut-says-space-radiation-is-causing-him-to-go-blind

Nicolas
2008-Dec-25, 11:43 AM
source: Pravda
cataract: also occurs a lot to people who've never been in space

So....I'd want to see evidence for the causal link

djellison
2008-Dec-25, 06:17 PM
Quite.

Does everyone who has flown in space have cataracts?

No.

Does everyone who HASN'T flown in space NOT have cataracts?

No.

Are the statistics between the two groups significantly different?

I doubt it.


Doug

JonClarke
2008-Dec-25, 10:06 PM
Pravada, the source of the story, is very much a taboloid these days, full of refrences to decoding UFO codes, cyclops cats, etc..

If you follow the links to the original it is full of tabloid speak like "Soviet cosmonauts burnt their eyes in space for USSR’s glory".

Lebedev is now 66. What is the likelihood of cataracts at that age?

Added in edit: According to Wikipedia, in the US, age-related lenticular changes have been reported in 42% of those between the ages of 52 to 64 and 60% of those between the ages 65 and 74. So the chance of Lebedev having some form of cataracts at his age seems very high. Of course the rapidity of onset and degree of degeneration might be unusal. But I wouldn't trust Pravada as a source for these. Anyway, cataracts are treatable, and I hope he gets it.

Jon

ravens_cry
2008-Dec-27, 01:33 AM
I read on the wikipedia page on Apollo evidence that many of the Apollo astronauts have gotten early onset cataracts from exposure to radiation, as have other astronauts on high radiation missions. And actually, whatever the cause, I remember reading in Maclean's magazine that cataracts are inevitable if you live long enough. And they are treatable, so this really is a very tabloidy act, making a mountain out of a molehill, to use a cliche.

matthewota
2008-Dec-27, 04:09 AM
I read on the wikipedia page on Apollo evidence that many of the Apollo astronauts have gotten early onset cataracts from exposure to radiation, as have other astronauts on high radiation missions. And actually, whatever the cause, I remember reading in Maclean's magazine that cataracts are inevitable if you live long enough. And they are treatable, so this really is a very tabloidy act, making a mountain out of a molehill, to use a cliche.

I don't consider Wikipedia as a credible source. Too many bogus edits and I see too many mistakes.

JonClarke
2008-Dec-27, 04:20 AM
I don't consider Wikipedia as a credible source. Too many bogus edits and I see too many mistakes.

It is still a useful start. And if you have a better source then point to it.

ravens_cry
2008-Dec-27, 04:57 AM
It is still a useful start. And if you have a better source then point to it.
And I would if I did.

JohnD
2008-Dec-29, 12:42 AM
Don't you guys do ANY research before you 'opine'?
Beyond Wikipedia, that is?
And do you imagine that this hasn't been investigated?

Radiation is known to be a cause of cataracts, and has been found to be significantly more common in atrsonauts and cosmonauts: http://www.springerlink.com/content/m5pcpbw5ram5fxb1/

In the Beaver Dam Eye Study, 40% of those over 75 had a cataract: http://cat.inist.fr/?aModele=afficheN&cpsidt=2150247

Please remember - this is a scientific MsB. You are required to provide evidence for your statements, or theories.

John

LaurelHS
2008-Dec-29, 01:36 AM
Michael Collins said in Carrying the Fire that if he ever got cataracts he would try to blame his Gemini X flight.

KaiYeves
2008-Dec-29, 02:46 AM
Even if it's true, which I doubt, it wouldn't stop me from going into space.

JonClarke
2008-Dec-29, 08:00 AM
Don't you guys do ANY research before you 'opine'?
Beyond Wikipedia, that is?

I have read moderately widely on the medical effects of spaceflight.

Despite your sobbery with respect to Wikipedia, it is usually an excellent starting point. The numbers in the Wikipedia artricle I quoted were based on this paper http://www.ncbi.nlm.nih.gov/pubmed/7395962



And do you imagine that this hasn't been investigated?

No, I don't imagine this at all. Hence my request for more information.


Radiation is known to be a cause of cataracts, and has been found to be significantly more common in atrsonauts and cosmonauts: http://www.springerlink.com/content/m5pcpbw5ram5fxb1/

The abstract of this article, which is all that I can access for free, does not say this at all.

A better source would be http://www.bu.edu/csp/EMMREM/papers/cataracts.pdf

This study indicates a slight increase in catacract incidence of high exposure astronauts after a few years, reach a maximum of 20% increase in incidence after 25 years and decrewasing after that. However, out of a sample population of 295, only three required cataract surgery.

My conclusion? Yes there is an increase, but severe cases are low. Certainly nothing would justify the "eyes burned out by spaceflight" language of Pravda

In the Beaver Dam Eye Study, 40% of those over 75 had a cataract: http://cat.inist.fr/?aModele=afficheN&cpsidt=2150247

This incidence is considerably lower than in the Framingham study. I have no idea why there is such a difference, except perhaps that there is considerable variability in terrestrial populations, or that different methodologies given different results. This may make conclusions of increased incidence among spacefarers very tentative, given the small sample size.


Please remember - this is a scientific MsB. You are required to provide evidence for your statements, or theories.

Hence my scepticism over a quote in Pravda, a gerneral statement based on overall reading round the subject, and a request for more information, followed by my own research independent of the discussion. Kindly do not accuse me of opining without some knowledge of the subject again.

Jon

geonuc
2008-Dec-29, 12:38 PM
I think Wikipedia is an excellent resource, particularly if you pay attention to the source references, as Jon does.

Arneb
2008-Dec-29, 05:56 PM
[sorry, redundant link]

Nicolas
2008-Dec-29, 06:33 PM
JohnD, I don't see how asking evidence in response to an article that doesn't give evidence or cite scientific sources would not be worthy of a scientific board. IMO it is the perfect scientific reaction. Researching it for yourself is nice if you have the time, but it is the task of the source making the claim to provide that evidence in the first place. Not the task of the people demanding the evidence. Make the claim, have the burden of proof, that stuff.

matthewota
2008-Dec-29, 06:54 PM
All I did was post the link.
It shows that astronauts and cosmonauts are just as gullible as other humans to nonsense. Ed Mitchell for instance.

Nicolas
2008-Dec-29, 07:35 PM
I wasn't referring to you Matthew, but to Pravda and even moreso the cosmonaut, who make the claim but cite no sources with evidence for that claim.

I don't know whether it's true or nonsense. That's where evidence comes into play.

JonClarke
2008-Dec-29, 09:44 PM
I wasn't referring to you Matthew, but to Pravda and even moreso the cosmonaut, who make the claim but cite no sources with evidence for that claim.

I don't know whether it's true or nonsense. That's where evidence comes into play.

Given Pravda's reputation, any connection between what Lebedev said and what he was quote as saying may be very tenuous indeed!

Jon