Show HN: Four numbers can predict your lifetime risk of a heart attack
knowyour4.com
knowyour4.com
This project was inspired by a personal experience I had--I put my numbers into a spreadsheet provided by the American Heart Association and found I had a 50% lifetime risk of a heart attack. Yikes!
I've gone to regular check-ups all my life and always been a little outside of the cholesterol guidelines, but I never knew how seriously to take that. I didn't know you could translate those numbers into percentage chance of getting a heart attack, whether I was "high" or "low," or how much I could improve by making lifestyle changes.
I figured there must be other people out there who are similarly ignorant about their own health, so I built this. (Please don't take this as a substitute for going to the doctor; there are all sorts of things your doctor can tell you that a web page can't. This is just for education!)
Please let me know if you have questions!
Is the "problem" with obesity only its impact on blood pressure and cholesterol? Or does obesity also increase risk in other ways in addition to worsening those factors?
BMI is archaic and a "one shoe fits all" metric. That doesn't mean that BMI is wrong - just that you should do more detailed diagnoses with your doctor to determine your health.
If BMI is saying you're obese, then get a comprehensive metabolic panel and lipid panel with your PCP, and go from there.
Mainly: I'm curious mostly about whether excess body fat on its own impacts cardiovascular health, or whether it does so only indirectly by increasing the risk factors this calculator uses.
Also note that you can appear perfectly thin, but have high blood pressure and cholesterol, and thus be at risk! So know your numbers. A lot of health is only revealed by what's going on within your body.
The back-and-forth of this discussion about BMI is entirely predictable, but doesn't it sort of miss the point? Isn't it possible -- and I mean this sincerely, even though it's wildly simplistic -- to just look at a human and determine if they're carrying around excess fat?
A lot of times when I hear people saying that BMI doesn't account for how much they exercise, I'm looking at the person saying it and they appear unfit. On the other hand, do we need BMI to tell us that a fit person is fit? What am I missing here?
Darren Sproles is 5'6" 190lb. Does he really fit into the same statistical categories as other people listed as overweight by BMI?
• BMI over-estimates obesity in athletes
• BMI under-estimates obesity in fat people
• BMI over-estimates obesity in tall people.
You claim to be "very active" so you might want to try other more accurate measures of body fat.
(Although 5'10 at 175 is higher end of normal and probably isn't worth worrying about if it's stable (lol archaic units))
It doesn't seem productive to hide away the advice part of it; and in particular it would be sensible to at least hint that there's more than just a risk percentage to come after you enter the 4 numbers (which, let's face it, most people won't know off the top of their heads!).
...
Okay, I got through with faked numbers; I just put 150, 60, and 120. Note: the results aren't all updated correctly if you change the numbers at the top and recalculate. E.g., this line in particular has different numbers than the rest: "You're doing pretty well! Your risk of heart disease is 18%. With ideal risk factors, your risk would be 18%."
My main complaints about the results:
There's no obvious reason it should to demand my email address before it'll share advice on how to improve my health (on whatever figure happens to be too low/high).
From the page: "First, enter your email. We'll use it to send you a copy of your report and follow up on the actions identified. No spam."
Eh... This sounds too much like I'm about to hit the part in the funnel where they start trying to sell me something. Right? "Enter your email for the free whitepaper" means "sign up for our sales email stream".
I wouldn't have any use for a copy of the report buried in my email history; if they actually want me to keep a copy for reference, that's what a PDF download is for.
Followup on the actions suggested sounds like a potentially useful feature which would legitimately need my email -- but right now, I don't yet know what kind of advice it's going to give (what if the next page reveals that it's hawking AcmeCorp Super-HDL-Booster Supplements?), I don't know if I want followup before they explain what that would entail, and so this is where I stop.
The visible front of the website is also actively anonymous -- the page is copyright "Heart" (?), all contact info even in the privacy policy is anonymous (just this domain name and a PO box). The PP itself is clearly boilerplate edited to match the site (including some odd errors; e.g., I caught this near the top: "We implement a variety of security measures enters, submits, or accesses their information to maintain the safety of your personal information.") -- so it talks about purchases, but I'm not sure that reveals anything at all.
But I really do think it's important to connect online efforts with real people. If this is a spare time project intending to help other people, great; take credit for it! -- to be straightforward that it's not provided by a doctor (okay), but also that it's not provided by a shady snake oil company that's redirecting you into its sales funnel.
I notice the creator is hiding, and I immediately want to know why.
What about electronic cigarettes?
And, of course, blood pressure is one of the four numbers.
(However if someone already have low blood pressure it might be dangerous for them)
Why not? Also, aren't marijuana cigarettes unfiltered, unlike tobacco?
I'm confused by the answer: Cigarette filters don't filter toxins? And they do reduce temperature?
You can't say this. There's a possibility that cannabis causes mental health problems in some people who don't have underlying disease. There's a stronger possibility that cannabis triggers mental illness in people who do have underlying disease but who would not otherwise have had an episode.
It is irresponsible to suggest that cannabis is harm free.
People like you do great harm to campaigns that aim to legalise drugs. Please stop.
I did not suggest that cannabis is harm free. I stated we cannot explicitly identified marijuana as the cause of illness.
How am I doing "great harm" to campaigns aiming to legalize drugs? (That's an honest question, I'm not quite processing your viewpoint on my argument, and am actually interested in your response.)
Yes you did - using phrases like "there are no known health risks" you dismiss all the evidence we have that cannabis can cause harm.
Here's just one link, but there are many other reputable sources. This one discusses lung health.
http://www.nhs.uk/news/2012/06june/Pages/cannabis-lung-healt...
> The report says that the constituents of cannabis smoke are similar to those of tobacco smoke apart from the presence of THC (which is only in cannabis) or nicotine (which is only in tobacco). This means that cannabis smoke has the same carcinogens (substances that cause cancer) as tobacco smoke, although concentrations of these may be up to 50% higher. Like tobacco, cannabis also contains toxic carbon monoxide
Saying that this is equivalent to "no known health risks" is intellectually dishonest.
The phrase used was "no known health detriments", by which I believe he meant a direct causal link, such as with cigarettes and lung cancer.
Besides the patronizing of the parent post, I do think your argument is valid. Mostly since you use the phrases "stronger possibility." But again, without clinical proof, your argument is only as good as parent's.
http://www.northwestern.edu/newscenter/stories/2013/12/marij...
"Teens who were heavy marijuana users -- smoking it daily for about three years -- had abnormal changes in their brain structures related to working memory and performed poorly on memory tasks, reports a new Northwestern Medicine® study."
"The brain abnormalities and memory problems were observed during the individuals’ early twenties, two years after they stopped smoking marijuana, which could indicate the long-term effects of chronic use. Memory-related structures in their brains appeared to shrink and collapse inward, possibly reflecting a decrease in neurons."
Current thinking is the body repairs that damage with clots and cholesterol. But, these repairs accumulate over time to occlude a blood vessel (atherosclerosis). If red blood cells can't get through, oxygen can't either, and heart cells downstream to the occlusion will die in minutes to hours.
Marijuana most likely generates a significant amount of toxins as well. However, marijuana smokers generally smoke less than cigarette smokers. Given that heart disease and cancer risk increases with the amount smoked, it would be reasonable to assume marijuana smokers are much less at risk (though the risk is nonzero). But, we don't have a clear conversion between marijuana and cigarette smoke yet. You may also consider that marijuana may be contaminated with other plants or chemicals.
Electronic cigarettes are possibly more safe than non-e cigarettes in terms of cancer risk (this is theoretical as no significant study has been done yet). However, some in vitro (cellular) research suggests nicotine may play a role in atherosclerosis discussed above. Also, nicotine can precipitate a heart attack if a heart is already diseased.
Are these are thing again? I was under the impression that it was 80's nonsense that's been debunked.
See http://en.wikipedia.org/wiki/Radical_(chemistry) for more detail
does this imply that if there's very little damage (due to inflammation or substance abuse) elevated cholesterol doesn't really matter?
Unless it contributes to increased addiction, the manufacturers generally try and reduce the unhealthy components of the cigarettes - making them more palatable and keeping the addicts alive for longer so they can make more money off of them. There's really no such effort with marijuana as it stands today.
I'm totally unqualified to make this statement, but I'd venture a guess that most of the 'toxins' that are natural byproducts of combustion - not just the tar - are present in significantly higher amounts in marijuana.
Sticking to the 4:1 ratio, someone who smokes 5 joints a day is basically a pack a day smoker.
Does 50% mean I'll get a heart attack in my 40s, or mean I'll get one in my 80s instead of getting cancer, etc.
What I'm getting at is that if nothing else kills you, eventually your heart will fail. Shouldn't it be possible to decrease my heart attack risk by increasing my cancer risk?
Your meta point is a good one—I would like to see a model that predicts either your total lifespan, or probability of living to (say) 80 years of age heart attack-free. Perhaps I'll try to get access to the raw Framingham data and build a model to do that.
(For this particular page, I just bootstrapped from the existing medical research, which, while it has its limitations, has at least been thoroughly studied.)
For height/weight, I'd assume meters and kg?
When you get your cholesterol measurements, do use mg/dL, mmol/L, or something else? What about blood pressure?
Ideally, there should be an ability to switch. Regarding height and weigh - its metric meters and kilograms. Not sure about others.
Thanks.
In any case I'm glad that I'm at relatively low risk despite being overweight (but a little less each day). I guess that low blood pressure and zero smoking are that good.
My caffeine intake is also zero (Ok, I think that cocoa powder has some, so not literal zero). I wonder if that has any effect on my risk, maybe something indirect through blood pressure.
[1] http://www.ncbi.nlm.nih.gov/pubmed/23280227 --- n.b. I haven't actually read the article, but I'm assuming the abstract isn't lying when it says "overweight was associated with significantly lower all-cause mortality".
Considering that, overall, my doctor believes I had a low risk of cardiovascular disease before I started exercising regularly, and now believes my risk to be lower, I take the risk numbers with a grain of salt - and a dab of butter.
Speaking of fat, as others have noted, total cholesterol may be meaningless. If I told you my total, you'd likely call an ambulance. But my triglycerides are low and my HDL/tri and HDL/total ratios are so good they are silly.
Based on everything my doctor knows - and she's scientifically minded, curious, and thorough, traits unusual in family doctors AFAICT - my risk of cardiovascular disease is in the low single digits.
Yet this test tells me my best case is mid 30s and my current close to 50.
Yeah, uh huh, I'm going to take medical advice from an app prepared by someone who lived an anecdote.
(No disrespect intended. Our personal experiences tend to not be transferable, no matter how much we learn about our case, because we learn about our case - not about all cases, with a dash of probability and a hint of objectivity.)
Total cholesterol: probably doesn't matter much
HDL: matters
Blood Pressure: I don't know
Smoking: matters
The models tend to be close to equivalent in their inputs: either total or LDL cholesterol (small-particle LDL is the one that drives atherosclerosis, but if the model includes HDL cholesterol, then it doesn't make a big difference in accuracy whether the other variable is total or LDL cholesterol), HDL cholesterol (seems to cause a protective effect, although randomized trials of HDL-boosting drugs haven't shown improvements, so may not be causal), blood pressure, and smoking. People also sometimes include newer biomarkers like triglycerides or hs-CRP, but they don't consistently show accuracy gains (LDL, triglycerides, and hs-CRP are highly correlated, so each one individually is a good predictor but having all three doesn't necessarily give you a more accurate model).
There's still a lot of active research to find out which of these variables are causal and which are merely associated with heart disease. For example, LDL-lowering drugs like statins do reduce the risk of heart attacks in randomized trials.
There are cases where BP matters less as well. For example the cochrane review on sodium consumption indicated that while lowering sodium intake aggressively did successfully lower BP, it resulted in worse mortality.
"Predicting the Thirty-year Risk of Cardiovascular Disease: The Framingham Heart Study" (http://circ.ahajournals.org/content/119/24/3078.abstract) reported that triglycerides were not statistically significant when added to a model that already contains total and HDL cholesterol:
"Standard CVD risk factors (male sex, age, SBP, antihypertensive treatment, total and HDL cholesterol, smoking and diabetes) were highly significant (0.01 level) in the multivariable model. DBP and triglycerides were not statistically significant and inclusion of LDL in place of total cholesterol did not improve model performance."
A couple cites of interest:
http://cpr.sagepub.com/content/3/2/213.short
http://www.ahjonline.com/article/0002-8703(86)90296-6/abstra...
http://circ.ahajournals.org/content/85/1/37.short
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2664115/
There is significant overlap in the explanatory power of these variables because they are not independent. So it is possible that "high" cholesterol has covariance with triglyceride:HDL ratio in the majority of the population sample (seems likely). In that case we should see people with "high" TC still have better mortality outcomes. Which we do see: http://www.ncbi.nlm.nih.gov/pubmed/11502313
But like I said, the Framingham study does seem like reasonable evidence. I'll look over the entire thing later.
There is also this interesting development, but I don't know enough to speak intelligently about it: http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2796.2006....
It is interesting to note that apo-b levels VERY closely track HDL:Trig ratio.
For ratios, this particular model is log-linear: risk = b^(w0 + w1log(cholesterol) + w2log(hdl) + ...)
So adding in variables to represent ratios would change the coefficients, but not the final risks.
For that last one, the "low cholesterol" bucket they allude to is people whose total cholesterol is <180 mg/dL. 180 mg/dL is exceptionally low, particularly for an older population. There's also a potential confounding effect when you study only total cholesterol (ignoring HDL)--your "low cholesterol" group of people includes a disproportionate number whose HDL ("good") cholesterol is also low, and who thus are actually at a high risk of heart disease according to models like the Framingham one.
My advice get genetically screened if you are worried and make changes. If you carry alterations on the 9p21 chromosome chances are you are at higher risk. If so you can simply eat more fruit and vegetables this has been shown in multiple studies to dramatically lower rates independent of other factors.
The graph animation was slow in my Firefox 33.
I'm using Firefox 33 and Chrome 38-ish for Mac.
I agree that total LDL is not a good indicator unless you do subfractioning, but I think you meant total cholesterol here, as LDL does not include HDL (that wouldn't even make sense!).
"I had a 50% lifetime risk of a heart attack. Yikes!"
not for nothing, but I entered in my numbers and got 68% and I smoke about a pack of day. If that's the case, then I'm not quitting any time soon.
(I'm also unclear as to why '90' systolic blood pressure is at an unexpected end of the graph, but...)
Feel free to email me if you have thoughts on what you've tried so far, and what you'd like to see ideally. Address is in my profile.
Even if true, drinkings bring your other risk factors so high( >Σ40%) that you are better of staying abstinent.
That's suboptimal when discussing something where the science is moving.
http://www.health2con.com/devchallenge/one-in-a-million-hear...
Are you using the Archimedes Indigo back end? https://archimedesmodel.com/indigo-api
The risk models for heart disease are simple enough that I just implemented them in Javascript based on the Framingham papers, although I did talk with one of the risk modelers at Archimedes to understand which models to use.
http://en.wikipedia.org/wiki/Body_mass_index#Limitations_and...
"Your lifetime risk of heart disease is 56% as of today. You can reduce that to 38% if you ... That would make your risk about 34% lower. Not too shabby!"
If your risk was lowered from 2% to 1%, that's a 50% reduction, but a 1 percentage point reduction.
But the graph shows 26%
For most people, the 10-year-risk becomes important in your 50's, 60's, and 70's and is used to guide treatment for e.g., statin therapy or anti-hypertensive medication.
If you're 30, your 10-year-risk is generally very low even if you treat your body terribly. :) So part of the motivation for showing the lifetime risk is to get people thinking about how to optimize their health for their life, since by the time your 10-year-risk is significant it's often too late to change your habits for diet/exercise.
I would like to believe it, but I can't seem to find that strong evidence anywhere.
That’s because it doesn’t exist, of course. We have been tragically misled for about 30 years.
This is N=2 but my wife and I switched to a low-carb/high-fat diet last summer and we are both at our ideal weight, higher energy than we have had in many years, and feeling absolutely fantastic. I think this is where the current metabolic science is taking us.
Their recommendation for consuming 5-12 servings of breads, cereals, pasta, 'whole grains' per day is like telling people they need to drink more soda.
Further, the harm in red meat consumption may be related to the use of preventative antibiotics in livestock and their diet in CAFO factories.
"Cholesterol" tends to get used to mean two different things, and even otherwise clear writers like Gary Taubes don't always explicitly denote which one they mean: 1) the amount of cholesterol in your blood, which is mostly produced by your liver. I.e., if my blood cholesterol is 300 mg/dL, should I be worried? 2) cholesterol in your diet. I.e., should you avoid eggs?
I'd say the scientific consensus is that blood cholesterol (particularly small-particle LDL) drives heart disease, but cholesterol (or saturated fat) in your diet doesn't drive blood cholesterol (<10% effect).
So low-fat/high-carb diets were a fallacy and are not "heart-healthy," it's fine to eat eggs, but you should still try to reduce your LDL cholesterol if it's high and boost your HDL cholesterol if it's low.
Another point, still not proved, is if high total cholesterol drives heart disease. As far as I know, there is evidence that it doesn't matter at all.
As said in other comments, tryglicerids and HDL matters a lot more, according to this evidence.
And I strongly disagree with you conclusion that low-fat, high-carb diets are a fallacy according to being "herat-healthy"
My impression is that your tool is based on misinformation.
> [..] but cholesterol (or saturated fat) in your diet
> doesn't drive blood cholesterol (<10% effect).
> [..] it's fine to eat eggs, but you should still try
> to reduce your LDL cholesterol if it's high and boost
> your HDL cholesterol if it's low.
Diet matters a lot. Apparently, it has been shown that for some people, milk fat in the diet correlates strongly with serum (blood) levels of cholesterol.
However, the effect of cholesterol in your diet seems to have little to no effect on your serum levels.
Serum cholesterol is actually pretty important: It is the precursor to Vitamin D (the other ingredient being sunlight exposure). For sure, it is an indicator of trouble, but it is unclear if it actually causes trouble itself or is part of the body's attempt to make things right.
Statins reduce cholesterol, and reduce the incidence of heart attacks, but they either increase or do not affect all-cause mortality (depending on which study you look at).
The science is far from settled on this, despite what most medical professionals would have you believe.
Blood cholesterol is a natural component of blood and is synthesized by all animal cells because it is an essential component of cell membranes. If you had no cholesterol in your blood you would be seriously ill.
Abnormal levels of cholesterol are associated with heart disease but it is not clear if they are the prime cause. The heart disease and abnormal cholesterol may both be caused by something else. There is evidence that excessive activation of the bodies inflammatory system may be more of a root cause.
(see http://www.sott.net/article/242516-Heart-surgeon-speaks-out-... for example)
I'll stick with Circulation, The Lancet, and JAMA, thank you very much. :)