[johmue]

It's the third option: I guess we all know it's not the viagra, but I would suggest it's also not the sex but rather what is associated with a lifestyle that includes the potential for sex: a lifestyle with connection, a partner and possibly friends. A bigger social group is pretty tightly related to better health outcomes

[vidarh]

We don't know any such things. Viagra has effects that could provide a plausible mechanism for a direct causal link. The article in particular points out that it directly interacts with amyloid and tau proteins, that are frequently implicated in Alzheimer's, and that they've explored it's effect on tau in vitro.

That of course is not proof of a causal link, but it's enough to justify follow up research.

[q1w2]

Viagra use indicates that the person has a partner(s) at an advanced age. This alone implies MANY lifestyle changes.

What would be interesting would be a comparison again Cialis (the competitor to Viagra).

[vidarh]

Hence why it requires further research before we can claim causality. My point was simply that assuming we "know" the causal link is something else is also unjustified without further research.

Especially given the size of the effect combined with the known interactions between Viagra and Tau proteins.

A comparison with Cialis might well be worth it down the line, but I don't see what it'd give before they've established whether or not there's a causal link.

[sneak]

> Viagra use indicates that the person has a partner(s) at an advanced age.

Or money.

[raducu]

That could be very easy to prove right or wrong: if it's the sex, then the wives of men taking viagra should be less likely to develop alzheimer's themselves.

[rp1]

Or look at men who have a similar amount of sex without taking viagra.

[raducu]

Well, yeah, but those men could be really healthy if at an advanced age they don't need viagra?

My grandpa whom I've never caught lying, told me that in WW2 Romania, as a very young conscript, he was given a medical examination... consisting of the nurse fondling his junk. Apparently they decided very fast he was healthy and the same for every other conscript, except for the only son of an aristocrat(most were tough peasants such as my grandpa) who would not get an errection.

A couple of weeks later, that young man who did not pass the "physical exam" got really ill and only my grandpa took pitty enough to carry him on his back to a hospital, where they guy died a couple of days later.

[agumonkey]

The neurological effect of physical intimacy are probably second to none.. surely it triggers a massive positive side effect on your neurons everytime it happens.