Does Prevention Work?

Recently, some authors that I highly respect posted an article to their website from a guest author. The guest presented an argument that we should not focus on treating people’s risk factors before they have evidence of actual disease, because we are turning too many people into “patients”, enrolling them in plans of care that could involve having them on treatment for years or even decades while they are still “well”, and long before they have manifested their disease process.

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While I agree that we need to be cautious about the “medicalization” of people, and turning people into patients (Yes, I’m looking at you AppleWatches and Oura rings), I believe that this guest author fails to appreciate the fact that cardiovascular disease is the leading cause of death globally and in the U.S., accounting for ~19.4–19.8 million annual global deaths (2021-2022) and over 900,000 U.S. deaths in 2022.  And while heart disease death rates have decreased by 66% from 1970 to 2022, it remains the #1 killer. 

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What is truly sad is that this is a solvable crisis. We have the tools to save lives and end this epidemic, yet this author argues that we should continue the same failed approach we have taken for over 50 years. For decades, “western” medicine has opted for a reactive approach to human health: wait for something bad to happen, then treat it. And we have developed some amazing medications and technologies and procedures to do exactly that.

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I want to tell you about two studies that motivated me to shift my career towards a different approach, and into Preventive Cardiology.

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The West of Scotland Coronary Prevention Study was what we call a “primary prevention trial”, meaning that it purposefully studied people WITHOUT disease (“secondary prevention” is the term that we use when we are describing people who already have disease, or have had an event). This trial, published in 1995, compared statin vs. placebo in 45-64 year old men with high LDL (“bad”) cholesterol levels. Over 6500 men were randomized to receive pravastatin 40 mg once daily or placebo for an average of 4.9 years. 

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This landmark study demonstrated that 5 years of statin therapy in men with high cholesterol significantly reduced the risk of having a heart attack, or dying from one. By the end of the trial, there was a 31% reduction in nonfatal heart attacks and death from heart disease (absolute risk reduction: 2.4%), and this was statistically significant.

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This study was the first to show that lipid-lowering therapy reduces all-cause mortality in a primary prevention population. 

But to me, what was even more important were the studies that came much later: 

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Ten years after the end of the study, the researchers went back and looked at how the participants were doing. At this point in time, only 38% of participants in the statin arm were still taking their statin, and 35% of people in the placebo arm had started a statin, so it was roughly similar. Which means that the only thing different about these groups was that 10 years earlier, one group had been on statin therapy for 5 years. Could just 5 years of statin use earlier in their lives really have made a difference? 

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The answer is yes: They found that approximately 10 years after completion of the trial, the risk of death from heart disease or nonfatal heart attacks was still lower in the pravastatin group! 10.3% in the placebo group and 8.6% in the pravastatin group.

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Twenty years later, the researchers again went back and looked at the people in this study. 20 year follow-up of the trial revealed a 31% relative reduction in the primary outcome with pravastatin. Participants assigned to just 5 years of pravastatin had a 30% reduction in the risk of heart attack and a 27% reduction in cardiovascular death over the 20-year follow-up period.

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And for all the statin worry-warts out there, there was no increased risk of death from non-cardiovascular causes nor an increase in incident cancers.

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I think it is important to highlight what is actually going on here:

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Almost 6600 men in mid-life were either given a statin for 5 years or placebo. Then the trial ended. And over the next 20 years, the groups basically equalized: Some people in the original statin group stopped their statins, some remained on it. And in the placebo group, some were placed on a statin by their PCPs, some were not.  

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What these trials showed was that simply taking a statin for just 5 years in mid-life led to a measurable and clinically important reduction in bad outcomes up to 20 years later. 

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Prevention works.

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Importantly, this legacy effect of preventive interventions does not just apply to the use of statins. 

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The TOHP trials (Trials of Hypertension Prevention) also revealed lasting benefits for another preventive intervention. TOHP I and TOHP II were major NIH-sponsored studies that took place from 1987–1995, investigating methods to lower blood pressure in individuals aged 30–54 with high-normal BP without medication. Results showed that weight loss and sodium/salt reduction effectively lowered blood pressure and the risk of developing hypertension. 

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But is the effect durable? 

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Once again, a follow-up study was performed 10-15 years later, obtaining follow-up information on cardiovascular outcomes or death for most of the participants. What were the results? 

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People with “prehypertension” assigned to a sodium reduction intervention experienced a 25-30% lower risk of cardiovascular outcomes in the 10 to 15 years after the trial. 

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Again, it is important to emphasize: after the trials were completed, the participants in both the intervention and “placebo” groups were allowed to behave (and eat) however they wanted for the next 2 decades. But being part of a time-limited 5 year sodium reduction trial earlier in their lives was still reaping benefits 10-15 years later. 

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What can we learn from these (and other) trials? 

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Prevention works. 

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Each year that you have elevated LDL-C levels contributes to progressive plaque accumulation. If you have an LDL-C of 125 mg/dL throughout your life, you will exceed critical thresholds for cardiovascular events at age 40 years old. But if you maintain an LDL-C level of 80mg/dL, you won’t hit that critical threshold until 62.5 years old.

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And even if cholesterol is your ONLY risk factor, an LDL-C level of ≥160 mg/dL remains independently associated with 50-80% increased relative risk of cardiovascular mortality over long-term follow-up, with an average reduction of about 4 years of life. 

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For decades, we have taken an approach where we wait for patients to manifest symptoms of a disease (“those who are already ill”) before we engage in treatment. But in a research analysis of 4.5 million patients who presented with a heart attack, 50% had no documented symptoms prior to their MI. And 63.4% of first MI patients had not been prescribed any preventive therapy prior to their event. 

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And while over 90% of people survive the initial event due to prompt medical intervention, the 1-year mortality rate following a first heart attack is approximately 10% to 20%. So for up to 1 in 5 people, the “wait to treat” approach results in catastrophic failure. 

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This is where Preventive Cardiology comes in. 

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I don’t think that we simply need to put everyone on medication. I believe that we need to educate people about estimates of their future risk, and allow them to choose an approach to alter that trajectory. If they can achieve their goals of lower risk through lifestyle alone? Amazing. If they need medication to help? OK, no problem: The meds are safe and effective. 

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The goal is reducing preventable catastrophic and tragic events.

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We all know that “the definition of insanity is doing the same thing over and over again and expecting different results”. 

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Heart disease is the #1 killer, and has been for over a hundred years. For most of that time, we have taken a reactive approach to treating it: wait for patients to manifest themselves, and try to save as many of lives as possible once they present. 

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Sounds like insanity to me.

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At Wisconsin Cardiology Associates, we believe in the power of prevention, and specialize in advanced methods of risk assessment. We hope to guide you through the process of evaluation and help you choose your best path to lower your risk. Have questions about the best way you can evaluate your risk of heart disease? Call us and make an appointment for a consultation.

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Photo by Museums Victoria on Unsplash

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References:

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NEJM. 1995;333(20):1301–1308

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NEJM . 2007;357(15):1477–1486

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BMJ. 2007 Apr 20;334(7599):885

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Eur Heart J. 2025 Oct 7;46(38):3762-3772

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J Am Coll Cardiol. 2018 Sep 4;72(10):1141-1156

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Circulation. 2018 Nov 20;138(21):2315-2325

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