Cardiology is renowned for its innovative procedures and cutting edge technology. However, one of my favorite scientific papers of 2014 did not address innovative techniques, DNA sequencing or new wonder drugs. It dealt with the fact that certain lifestyle habits and the absence of abdominal obesity may prevent most heart attacks.
Toady, chronic noncommunicable diseases are one of the biggest challenges of medicine and healthcare in general. One hundred years ago doctors were busy dealing with infections; pneumonia, tuberculosis and gastroenteritis (1). Today it is heart disease, cancer, dementia, diabetes, and obesity.
The pandemic of chronic diseases seems to have started only a few decades ago. Although the underlying causes are multifactorial, modern western lifestyles are often blamed, implying that these diseases are potentially preventable.
However, the knowledge that lifestyle contributes to disease doesn’t necessarily provide an easy solution. Our lifestyle choices are easily manipulated by the external environment. We are constantly bombarded with advertisement, and the internet provides a steady flow of information that may be both overwhelming and confusing. What should we believe and who can we trust?
Of course, every doctor should educate their patients about the relationship between lifestyle and disease. However, as Dr Bernard Lown, a great cardiologist and Nobel Peace Prize recipient once said: “Diligent prevention, unfortunately, plays second fiddle to heroic cures.”
It’s a fact that cardiologists are often more interested in the high-tech diagnostic and therapeutic aspects of their discipline than in preventive lifestyle measures. However, the 2014 paper I mentioned before certainly suggests that the latter may be much more effective when it comes to reducing the burden of heart disease in our society.
Five Tips on How to Prevent Heart Attack
In September 2014, a paper by scientists lead by Agneta Åkesson PhD at Karolinska Institutet, Stockholm, Sweden, was published in the Journal of the American College of Cardiology (JACC), suggesting that five basic lifestyle factors may prevent approximately 80 percent of heart attacks in men (2).
But it’s not only about men because another study published 2007 by the same group of researchers observed that low-risk dietary and lifestyle behaviors may prevent 77% of heart attacks in women (3).
I’m not sure whether the medical community understands the potential impact of these findings. At least the 2014 paper didn’t to steal many news headlines.
About 600,000 people die of heart disease in the United States every year. This is approximately 25% of all deaths (3). Coronary heart disease, the most common cause of heart disease causes nearly 380,000 deaths annually.
Every year about 720,000 Americans have a heart attack (4). Of those, 515,000 are a first heart attack. Imagine if this number could be reduced by 80%, to 103.000 cases annually, with a therapy that is mostly without side effects and risks.
In 1997, the Swedish researchers sent a questionnaire that included approximately 350 items to men aged 45-79 years residing in two counties in central Sweden. A total of 48,850 men returned the questionnaire, but those with a history of cancer, coronary heart disease, self-reported hypertension and self-reported high cholesterol were excluded from this particular analysis, leaving 20,721 for the main analysis.
The men were followed for a mean of 11 years. During that period, there were 1,361 cases of a first myocardial infarction (heart attack).
The scientists studied the risk of heart attack in relation to the following five low-risk lifestyle behaviors: a healthy diet, moderate alcohol consumption, no smoking, being physically active, and having no abdominal obesity.
1. A Healthy Diet
After mutual adjustment for other elements of the low-risk profile, individuals with the highest score for a healthy diet had an 18% lower risk of heart attack than those with lower scores for the healthy diet.
A healthy diet was identified according to a Recommended Food Score developed by Kant and coworkers (5). This score emphasizes foods such as fruits, vegetables, legumes, nuts, reduced-fat dairy products, whole grains, and fish.
A non-Recommended Food Score was defined based on 21 food items including red and processed meat, fried potatoes, solid fats, full-fat cheese, white bread and refined cereals and various sweet foods.
The men with the highest Recommended Food Score were more likely to have a higher level of education and were less likely to smoke or live alone, compared to men with lower scores of recommended foods.
Interestingly, men with the highest Recommended Food Score had a mean non-Recommended Food Score of 17 while those with lower scores of recommended foods had a mean non-Recommended Food Score of 15.
Although not mentioned in the paper, this suggests that those who ate the most “healthy” food didn’t eat less of the “unhealthy” food products.
Furthermore, mean daily energy intake was 2,900 kcal among that 20 % with the highest Recommended Food Score but 2,700 among the others.
A varied diet consisting of fruits, vegetables, legumes, nuts, reduced-fat dairy products, whole grains and fish is associated with approximately 18% lower risk of having heart attack.
2. Moderate Alcohol Consumption
A low-risk alcohol group comprised men who consumed moderate amounts of alcohol (10-30 g/day). This is usually defined as no more than two drinks per day for men.
After adjustment for other low-risk profile elements, moderate alcohol consumption was associated with 11% lower risk of heart attack.
Previous studies have suggested that moderate alcohol consumption may provide cardiovascular benefits.
However, because heavy alcohol consumption is associated with a number of disease conditions and increased mortality, it is very difficult for the clinician to recommend moderate consumption of alcohol in order to reduce the risk of cardiovascular disease.
Recommending people who don’t drink to start drinking in order to achieve possible health benefits is also highly controversial.
For those who already drink, it is important to understand that the evidence suggesting that alcohol improves health only applies to light or moderate drinking and not to binge drinking or heavy drinking.
Moderate alcohol consumption is associated with 11% lower risk of heart attack
3. No Smoking
Never smokers and those who quit smoking > 20 years ago were classified as non-smokers.
Not smoking was associated with 36% lower risk of heart attack after adjustment for other low-risk profile elements.
Of course, this doesn’t come as a surprise. The evidence linking smoking to increased risk of myocardial infarction and death is incontrovertible (7). However, the results highlight the huge health benefits of not smoking.
Not smoking is associated with 36% lower risk of heart attack
4. Being Physically Active
Physical activity was assessed by the equestionnaire. Participants reported their level of activity at work and home and during leisure time in the year before the study started.
A low-risk physical activity behavior included both daily non-exercise physical activity (walking/bicycling) and a more vigorous weekly exercise, pre-specified according to criteria from another study (3).
After statistical adjustment, men who were physically active had a 3% lower risk of heart attack compared to those who were not physically active.
The importance of exercise for cardiovascular health has been previously documented. Fifteen years ago the Honolulu Heart Program clearly illustrated the effect of regular walking, suggesting that the risk of coronary heart disease is reduced with increases in distance walked (8).
Physical activity is associated with a 3% lower risk off heart attack
5. Having No Abdominal Obesity
Central or visceral obesity has been found to be a strong marker of cardiovascular risk in a number of studies.
The Swedish investigators defined abdominal obesity as a waist circumference > 95 cm (38 inches).
After adjustment for other low-risk profile elements, the absence of abdominal obesity was associated with a 12% lower risk of heart attack.
The absence of abdominal obesity is associated with a 12% lower risk of heart attack
The Take-Home Message
Although the study by Åkesson and coworkers defined five separate low-risk elements associated with lower risk of heart attack, it also underscores the importance of multiple combined lifestyle habits.
A total of 1,724 (8%) men had none of the five low-risk elements present, and 166 (10%) of that group suffered heart attacks.
In contrast, 212 (1%) men had all five low-risk elements. Of those only three (1.4%) had heart attacks.
Therefore, almost 4 of 5 heart attacks may be preventable with a combined low-risk behavior.
In an accompanying editorial to the paper in the JACC (9) Darius Mozaffarian MD wrote: “In light of the breadth of previous mechanistic, physiological, observational, and clinical trial evidence on the impact of lifestyle, it is time to prioritize these most basic and fundamental behaviors to reduce the health and economic burdens of cardiometabolic diseases.”
So my message is simple:
If you eat healthily, don’t smoke, consume alcohol in moderation, regularly exercise and avoid overweight you will greatly reduce your risk of having a heart attack. These measures are more effective than any known medical therapy. Most people don’t need complex technology or a magic pill to avoid heart disease.