As the authors of the study say, patients are interested in all-cause mortality, not specifically in cardiovascular mortality. Specialists may be blinded by their own specialization, but the most important outcome for you as a person is whether you live or die, and not whether you will have a heart attack or not.
If I reduce my own ACM and increase risk of a heart attack at the same time, it still looks like a good trade-off.
I do not disagree with your opinion. I also think more research is needed.
However, one must not read too much into observational studies, either, as many times their interpretation isn't corroborated by stronger science. A good resource for laymen on how to read studies would be this one:
"Meanwhile, minimizing the risk of CVD, the leading cause of death worldwide, does seem like a good idea, no?"
This is the problem of modern medicine in a beautiful shortcut. Everyone is concentrated on their own domain. Oncologists treat cancer, cardiologists treat CVD. Few pay attention to the survival of the whole body, which is what you actually want.
Reducing the risk of CVD only makes sense if you reduce all-cause mortality at the same time. A therapy that would protect your heart at the cost of, say, increasing cancer risk, would be almost criminal to administer.
Now I don't want to claim that this is what now happens. But 12 million people in the developed world is an enormous statistical set and there likely won't be any weird outliers dragging the total result into implausible values.
Reading quickly through, I also notice that the overall effect of cholesterol on mortality seems to go significantly down with increasing age, which is something that has already been observed.
I certainly wouldn't be so favorable towards contemporary medications and at the same time so dismissive towards the observational studies. Quite a lot of CVD mortality reduction since the 1960s comes from surgery (stents etc.), from reduced prevalence of smoking and from early treatment of high blood pressure. Anti-cholesterol drugs are pretty deep in the list of interventions by total efficiency.
> Meanwhile, minimizing the risk of CVD, the leading cause of death worldwide, does seem like a good idea, no?
Maybe. I read a bunch of papers on cholesterol and statins a few years ago, and my recollection of the results is roughly as follows. High LDL and high LDL:HDL ratio are consistently associated with higher risk of mortality from CVD, and this seems to be partly (but perhaps not entirely) causal. Statins can lower LDL and can improve this ratio, and for some groups of patients they seem to be an effective intervention for reducing risk of serious or fatal CVD.
However, in the studies I looked at, statin therapy was only demonstrated to reduce all-cause mortality in certain groups of patients who already have CVD, or who don't have CVD but have extremely high LDL (or maybe it was LDL:HDL ratio, don't remember). In groups with lower risk, the benefits were not as great and seemed to be outweighed by the side effects in terms of all-cause mortality, and given that some of the side effects are immediate I would guess that this is also true for quality of life.
This also meshes with the article's data that total cholesterol has a U-shaped relation to mortality. To the extent that this is causal, lowering total cholesterol with statin therapy may not be helpful unless it was really high to begin with.
So my takeaway was that statins are a useful class of drug for some people, but that in America they are probably also overprescribed. My research might have gotten the wrong answer though. Obviously do your own and/or listen to your doctor.
If I reduce my own ACM and increase risk of a heart attack at the same time, it still looks like a good trade-off.