(1) just spoke with a doctor[1] who’d looked into it a bit. he basically wasn’t worried about it at all — his take was (paraphrasing quite a bit):
causes of heart failure are numerous & complex — it’d be really confusing mechanistically if melatonin affected a sufficiently large subset of those causes sufficiently strongly to have this strong of an effect.
also, because they’re so numerous & complex, it seems pretty implausible that they could’ve done even close to a sane job of manually controlling for all of the right variables.
[this bullet added by saul, not explicitly said by the doctor but he sort-of implied it] in particular, badness of insomnia is comorbid with extent of lots of other bad stuff. i.e. it’d be reasonable to expect having a prescription for melatonin selects for having very bad insomnia, which then seems like a straightforward causal factor for getting heart failures. it’s obviously possible they did some manual controlling for this, but since we don’t have the full paper, we can’t tell (and it seems like it’d be pretty tough to actually effectively control for this).
causes of heart failure typically take quite a while to build up; it’d be surprising if it only took melatonin 5 years to have such a significant effect.
we naturally produce some melatonin, and the amount one would exogenously supplement isn’t (typically, at least for prescribed patients) substantially higher than what you’d expect to see in one’s natural range of endogenous melatonin production.
if the american heart association was actually worried about this, they’d have done some public messaging independent from the paper abstract — it’s possible such a message is forthcoming, but we probably should have expected to see something about it by now.
(2) i’ve emailed the authors asking for the full paper. i’ll aim to keep this thread updated with thoughts if/when the paper arrives in my inbox!
doctor was a psychiatrist, not a cardiologist or internal medicine doctor — so though you should take it with a grain of salt, he did still get an MD. which implies way more medical knowledge than i have, at least!
some updates:
(1) just spoke with a doctor[1] who’d looked into it a bit. he basically wasn’t worried about it at all — his take was (paraphrasing quite a bit):
causes of heart failure are numerous & complex — it’d be really confusing mechanistically if melatonin affected a sufficiently large subset of those causes sufficiently strongly to have this strong of an effect.
also, because they’re so numerous & complex, it seems pretty implausible that they could’ve done even close to a sane job of manually controlling for all of the right variables.
[this bullet added by saul, not explicitly said by the doctor but he sort-of implied it] in particular, badness of insomnia is comorbid with extent of lots of other bad stuff. i.e. it’d be reasonable to expect having a prescription for melatonin selects for having very bad insomnia, which then seems like a straightforward causal factor for getting heart failures. it’s obviously possible they did some manual controlling for this, but since we don’t have the full paper, we can’t tell (and it seems like it’d be pretty tough to actually effectively control for this).
causes of heart failure typically take quite a while to build up; it’d be surprising if it only took melatonin 5 years to have such a significant effect.
we naturally produce some melatonin, and the amount one would exogenously supplement isn’t (typically, at least for prescribed patients) substantially higher than what you’d expect to see in one’s natural range of endogenous melatonin production.
if the american heart association was actually worried about this, they’d have done some public messaging independent from the paper abstract — it’s possible such a message is forthcoming, but we probably should have expected to see something about it by now.
(2) i’ve emailed the authors asking for the full paper. i’ll aim to keep this thread updated with thoughts if/when the paper arrives in my inbox!
doctor was a psychiatrist, not a cardiologist or internal medicine doctor — so though you should take it with a grain of salt, he did still get an MD. which implies way more medical knowledge than i have, at least!