Gordon Fox • June 9, 2025
Decisions in HCM: My Risk Estimate was Wrong!

by Gordon Fox: 5th in a series

You've been told that you had a high risk - say, 5% - of something dangerous, like a lethal arrhythmia, in the next year. Twelve years later there hasn't been a hint of that event occurring. That's great! But many people understandably are annoyed: they were told they were at risk, they got the treatment (an ICD for example), but it hasn't actually been needed. Sometimes people feel as though they were misled.

Reasons this can happen

There are many reasons why expected events don't always occur. Some possibilities include these:

  • The estimate was a probability, not a prediction. Doctors don't have crystal balls; they tell you that the chance of it happening is large or small, not that it will or won't occur. If you are told that the risk of a dangerous arrhythmia is high, and it doesn't occur, the doctors telling you that were not wrong.  Even with high risk estimates, sometimes the event never happens. After all, if the risk of something bad is only 1% per year, about 1 out of 100 people will have that happen, each year. 

  • The risk estimate is for a population, but you're an individual! If you were told that there is a 90% chance of a bad event occurring, that comes from the fact that 90% of people with similar characteristics had that event. But individuals either have the event or they don't. They don't have 90% of the event. 

  • The science wasn't understood as well when the estimate was made as it is today. Risk estimates are statistical, based on the science known at the time. But our knowledge grows over time. As we learn more, our estimates get modified. That is probably not what you want to hear as an individual, but it's encouraging for us in the long run!


The first two possibilities both mean that the estimate was good. It is very easy to misinterpret probabilities. Here's a confession from a scientist who has worked with statistics his entire career: everyone misinterprets statistics sometimes, including me. Just as we tend to misinterpret a statement like "65% chance of rain today" as meaning that it will rain, most of us misinterpret a statement like "only 1% of people having this medical procedure have a negative outcome." We take it to mean something like “Oh, good, I won’t have this bad thing happen to me.” But some people do, and sometimes that person is you or me.


The third possibility - the science behind a risk estimate has changed - is the one that seems most disturbing. It doesn't happen that often, and because of the way science works, a bad estimate gets corrected eventually. The most important thing to realize here is that the best your doctors can do is to use the best science that's known at the time. That’s a lot better than asking your doctor to guess.

Conclusion

Most cases of "my risk estimate was wrong" are really misunderstandings about what a risk estimate is. Don't feel too bad if you make this mistake: it is very easy to do!  Probability is one of the slipperiest ideas that we have to use.

Read Part 4: Decisions in HCM: Where do Risk Estimates Come From?

HCMA Blog

August's Topic is Newly Diagnosed

By Sabrina Cuddy • August 1, 2025
On a background of pink

Call to ACTION! Urge Congress to Invest in Medicaid and Medicare! No Cuts to these crucial programs!

By Julie Russo • July 31, 2025
Sixty years ago, Medicaid and Medicare were established when President Lyndon B. Johnson signed the Social Security Amendments into law. The programs were a larger part of Johnson's "War on Poverty" agenda to combat inequality. Sixty years later, Medicaid and Medicare are under attack in ways that we could never have imagined. With the passage of the One Big Beautiful Bill Act (OBBBA), $1 trillion was cut from Medicaid and Medicare―the largest health care cut in U.S. history. As a result of the budget package, more than 15 million people will lose health insurance, hundreds of rural hospitals will close, and approximately 51,000 people will die preventable deaths each year. Congress voted for this harm, and Congress can fix it. We need them to invest in Medicaid and Medicare in order to undo this damage. Click here to send a message to Congress telling them to invest in these critical programs, not cut them. OBBBA is the exact opposite of the "War on Poverty." The bill was passed with brutal cuts to health care to fund more tax handouts for the very wealthy. It took from the poor to give to the rich. The unpopularity of these cuts cannot be overstated. Eighty-three percent of the American public, including three in four Republicans, has a favorable view of Medicaid. Congress must hear from us loud and clear: reverse course, undo the harm to Medicaid and Medicare, and protect health care for more than 71 million people. Join us in sending the message to Congress to invest in these critical programs, don't cut them. 1 The Truth About the One Big Beautiful Bill Act’s Cuts to Medicaid and Medicare 2 Research Memo: Projected Mortality Impacts of the Budget Reconciliation Bill 3 Medicaid keeps getting more popular as Republicans aim to cut it by $800 billion

Lisa's Letter - July Newsletter

By Lisa Salberg • July 3, 2025
Summer, greetings to all our big-hearted friends As July approaches, our focus is already on the fall and preparing for some major events, including our annual meeting coming up in October. July will also find us on the west coast in Seattle conducting a regional patient education meeting as part of our big-hearted warrior tour. We have been following the generic drug quality issue in the United States very closely and encourage you to watch the series starting with our Hill briefing in April and following with the additional webinars with our partners at Medshadow and the People's Pharmacy, and of course the ProPublica series of articles. See them all here . We are happy to have a new team member on board - we welcome Pam as our coordinator of both our All Hearts Collaborative and Hearts and Minds project. Over the next few months, you're going to be learning more about these two amazing initiatives and how we are working to provide better services for big hearts regardless of where you live, so we are meeting all of our big-hearted friends where they are. Please stay tuned for updates from these projects coming soon. We are also creating new volunteer opportunities and engagements that we hope will make it easier for you to participate in spreading the message of the importance of diagnosis, the importance of community readiness related to CPR and AED use and, of course, helping patients get to their ultimate diagnosis and getting them on the proper treatment pathways. This July I would like to recognize all of the special birthdays in my family, including HCMA Center of Excellence coordinator, Stacey Titus-brown and my daughter Rebecca Salberg. It's a milestone birthday for Becca - it’s hard to believe I have a 30-year-old child. Wishing you all a happy and healthy summer. Go build some memories!
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