Yvain comments on Living Forever is Hard, or, The Gompertz Curve - Less Wrong
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This isn't an anti-aging strategy, but it is an anti-death strategy: low-dose aspirin. As explained in this New York Times article on December 6, 2010, "researchers examined the cancer death rates of 25,570 patients who had participated in eight different randomized controlled trials of aspirin that ended up to 20 years earlier".
Eight. Different. Randomized. Controlled. Trials. Twenty-five thousand people.
They found (read the article) that low-dose aspirin dramatically decreased the risk of death from solid tumor cancers. Again, this ("risk of death") is the gold standard - many studies measure outcomes indirectly (e.g. tumor size, cholesterol level, etc.) which leads to unpleasant surprises (X shrinks tumors but doesn't keep people alive, Y lowers cholesterol levels but doesn't keep people alive, etc.). Best of all is this behavior: "the participants in the longest lasting trials had the most drastic reductions in cancer death years later."
Not mentioned in the article is the fact that aspirin is an ancient drug, in use for over a century with side effects that, while they certainly exist, are very well understood. This isn't like the people taking "life-extension regimens" or "nootropic stacks", who are, as far as I'm concerned, finding innovative ways to poison themselves.
Yet the article went on to say this:
I'm a programmer, not a doctor - but after looking around, I concluded that the risks of GI bleeding were not guaranteed fatal, and the risks of hemorrhagic strokes were low in absolute terms. Also, aspirin is famously effective against ischemic strokes. According to Wikipedia: "Although aspirin also raises the risk of hemorrhagic stroke and other major bleeds by about twofold, these events are rare, and the balance of aspirin's effects is positive. Thus, in secondary prevention trials, aspirin reduced the overall mortality by about a tenth."
So unless aspirin's risks are far more grave than I've currently been led to believe, as far as I'm concerned, people saying "hey, even if you're not subject to aspirin's well-known contraindications, you shouldn't start low-dose aspirin just yet" are literally statistically killing people. Cancer is pretty lethal and we're not really good at fixing it yet, so when we find something that can really reduce the risk (and there aren't many - the only other ones I can think of are the magical substances known as not-smoking and avoiding-massive-doses-of-ionizing radiation), we should be all over that like cats on yarn.
I make damn sure to take my low-dose aspirin every day. I started it before reading this article on the advice of my doctor who thought my cholesterol was a little high - I'm almost 28, so it'll have many years in which to work its currently poorly understood magic.
That said, this reduces the risk of one common cause of death (two or three if you throw in heart attacks and ischemic strokes). There are lots of others out there. Even if you could avoid all of them (including the scariest one, Alzheimer's - it's insanely common, we have no fucking clue what causes it or how to stop it, and it annihilates your very self - even if cryonics is ultimately successful, advanced Alzheimer's is probably the true death), humans pretty clearly wear out with an upper bound of 120 years. Maybe caloric restriction can adjust that somewhat. But I think I'll sign up for cryonics sooner rather than later - I'm in favor of upgrading probability from "definitely boned" to "probably boned but maybe not".
The meta-analysis you cite is moderately convincing, but only moderately. They had enough different analyses such that some would come out significant by pure chance. Aspirin was found to have an effect on 15-year-mortality significant only at the .05 level, and aspirin was found not to have a significant effect 20-year-mortality, so take it with a grain of salt. There was also some discussion in the literature about how it's meta-analyzing studies performed on people with cardiac risk factors but not bleed risk factors, and so the subjects may have been better candidates for aspirin than the general population.
The Wikipedia quote you give is referring to secondary prevention, which means "prevention of a disease happening again in someone who's already had the disease". Everyone agrees aspirin is useful for secondary prevention, but there are a lot of cases where something useful for secondary prevention isn't as good for primary. In primary prevention, aspirin doesn't get anywhere near a tenth reduction in mortality (although it does seem to have a lesser effect).
I would say right now there's enough evidence that people who enjoy self-experimentation are justified in trying low-dose aspirin and probably won't actively hurt themselves (assuming they check whether they're at special risk of bleeds first), but not enough evidence that doctors should be demonized for not telling everyone to do it.
Can you provide your reference for this? I looked at the meta-analysis and what I assume is the 20-year follow-up of five RCTs (the citations seem to be paywalled), and both mention 20-year reduction in mortality without mentioning 15-year reductions or lack thereof.
Edit: Never mind, I found it, followed immediately by
I'd like to see 20-year numbers for people who maintained the trial (and am baffled that they didn't randomly select such a subgroup).
Their selection methodology on p32 appears neutral, so I don't think they ended up with cherry-picked trials. Once they had their trials, it looks like they drew all conclusions from pooled data, e.g. they did not say "X happened in T1, Y happened in T2, Z happened in T3, therefore X, Y, and Z are true."