Hacker News Reader

Comment by ProjectArcturis | Hacker News Reader

Confounded stats, of course. Older people who are physically and mentally healthy enough for sex are far less likely to have Alzheimer's.

View on HN

Agree this is a very possible explanation. Though it is also possible that the use of viagra leads to more sexual activity for the elderly which promotes and maintains their health to begin with. So not directly attributable to the pharmacology of the viagra but still a contributing factor to the result.

Off-label uses that appear to actually be effective include altitude sickness and prevention of SIPE (Swimming Induced Pulmonary Edema). I take it for the latter, and it's remarkable. No Sildenafil = I cough up blood after just a few minutes swimming in cold water (as in a triathlon). Sildeanfil = no ill effects whatsoever. I'm unclear how a vasodilator would impact a neurological disease.

Asking because I am genuinely curious, if you are willing to share: What mindset do you have where you keep doing an activity that normally results in you coughing up blood? I know that sounds like a super disrespectful question, it's just the sort of thing I think about a lot due to having some health related activity restrictions that I've had to negotiate with myself. Always interested in what other people's journeys are in this space.

Ha, fair. I love open water swimming and triathlon, and I can do it in not-cold water or a pool indefinitely, plus the Sildenafil entirely prevents it in cold water. Even without Sildenafil all I have to do is stop swimming and I'm fully better after an hour or so.

Well that's good! I imagine the first time it happened must have been disturbing.

Yes. The first time it happened was in the Hudson River in the NYC triathlon. I thought for sure that I'd just ingested some sludge, and I went on to complete the race, after which I was sent to the hospital (I walked). My pulse ox was 86. Most triathlon deaths occur during the swim portion of the race and are attributed to cardiac events, often SCD, but pulmonary edema may actually be the primary cause. A teeny bit of education (chest congestion? get out of the damn water!) could save lives, but nobody in the business of triathlon wants to scare off new participants, since the amateur fee-paying end of the sport is really the whole game.

Wow, I had no idea. That would not have been on my list of potential dangers from long swims at all!

This off-label use of sildenafil for SIPE was part of a bigger scandal in the US Navy SEALs. Specifically, during the selection course for the SEALs, so many recruits suffered from SIPE it was common for many of them to surreptitiously take Viagra and keep training.

One soldier drowned as a result and another collapsed on land after a punishing swim and died.

https://www.nytimes.com/2022/08/30/us/navy-seal-training-dea...

I participated in the clinical trial at Duke that's linked to from that story, which honestly was a blast. That the medics let this guy keep training is astonishing to me. If they measured his pulse ox and sent him back in anyways, that's criminal. Also, as I understand it, Sildenafil during dives is a bad idea (something about seizures) which might be why it's "banned" in SEAL training.

But who funded the Duke study that surfaced Sildenafil as a candidate drug? The Navy SEALs, of course.

The biggest thing you can do for Alzheimer's is be physically fit at mid life. I don't suppose that's correlated with sex and Viagra usage... Oh wait.

I realize anecdotes aren't data etc. etc. but my grandpa was very fit up through retirement (and stayed spry after retirement) since he repaired dishwashers, washing machines, and dryers for his whole career. Still got an absolutely terrible case of Alzheimer's that led to his death (and made me much more worried about my potential of getting it when I get older). Won't even try to think about if he and my grandma were sexually active though, too gross.

So being physically fit definitely doesn't guarantee you won't get Alzheimer's.

Yeah, it's not a guarantee. Sorry about your grandpa. However, it is the strongest preventative measure we know about currently.

Just like we know exercise is one of them best things you can do for cardiovascular health as well, but it doesn't mean fit people don't get heart attacks.

There is also a confound in the other direction too, people who need sildenafil for erections are probably less healthy than ones who don't

Maybe, maybe not? One reason for a sildenafil prescription could be prostrate surgery for cancer. If that works, and it's a one-and-done, then no further health problems from that should surface. OTOH, if one is taking sildenafil because of side effects of blood pressure medicine, then yeah, there's a point to be made there. OTOOH, some folks take it for side effects of some traumatic event, which did not necessarily have any effect on overall health.

So I'm not so sure that a sildenafil prescription is a reliable health indicator.

If you are getting prostate surgery, they are likely taking the whole thing and the patient’s sex life is effectively over.

The win is not having to wear diapers or use a catheter, which is more and more the outcome.

Sex someday perhaps.

My argument isn't "obviously all the confounds run in this direction". Just we don't know if people who use sildenafil or healthier or less healthy than the general population. I suspect it's a function of age, younger people prescribed sildenafil are probably less healthy than age matched controls, and older people are more healthy than age matched controls.(because they have to be with with it and fit enough to convince someone to have sex with them, and be healthy enough to have sex)

that is the weakness of the study design...."retrospective case–control pharmacoepidemiologic analyses" cannot really control for confounders as well as RCT

Reply on news.ycombinator.com