11 hours ago
Sudden Cardiac Arrest Is Highly Preventable: Here's How
This transcript has been edited for clarity.
This is Dr JoAnn Manson, professor of medicine at Harvard Medical School and Brigham and Women's Hospital. I'd like to talk with you about a recent report in the Canadian Journal of Cardiology that addressed the modifiable risk factors for sudden cardiac arrest, the extent to which this outcome is preventable, and the percentage of cases that could be averted by changes in modifiable risk factors.
There's been surprisingly little research on this subject. Most of the research on sudden cardiac arrest has looked at genetic factors and clinical risk factors that are managed with pharmacologic agents, such as hypertension, high cholesterol, and diabetes, and proximate risk factors like what the patient was doing shortly before the sudden cardiac arrest. However, there's been very little research on the role of behavioral and lifestyle factors in long-term studies. It's important to have this research because we know that sudden cardiac arrest is highly fatal in about 90% of cases. In the US alone, there are more than 200,000 cases per year, and more than double that if we include total cardiac arrest inside and outside of the hospital.
In the present study, researchers leveraged the large-scale UK Biobank, which included more than 500,000 participants whose mean age was 56 years and about 50% of whom were women. Over a follow-up of 14 years, there were about 3100 cases of incident sudden cardiac arrest. The researchers looked at about 125 risk factors and linked 56 of those factors to the risk for sudden cardiac arrest. These included lifestyle, behavioral, adiposity, psychosocial, and environmental factors.
What they found was that the American Heart Association Life's Essential 8 factors were generally strongly related to risk for sudden cardiac arrest. For example, sedentary lifestyle, higher adiposity, higher waist circumference, short sleep duration (less than 7 hours per night), and tobacco use were associated with an increased risk. Other factors that were also linked to sudden cardiac arrest risk included psychosocial factors (eg, depressive symptoms, low mood, social isolation), dietary factors (eg, low fruit and vegetable intake), and air pollution.
The researchers used Mendelian randomization to evaluate the likelihood of a causal relationship. In these analyses, about nine factors were determined to be causally related. These factors included adiposity factors, low fruit intake, low educational level, and some of the mood-related factors. Overall, they estimated that between 40% and 63% of sudden cardiac arrest cases could be preventable by reducing or even fully eliminating these risk factors.
These findings underscore the importance of primary prevention, not only to nonfatal or total coronary heart disease and cardiovascular events, but also to sudden cardiac arrest. These results suggest that more could be done in terms of informing our patients about these risk factors in order to lower their risk — both informing them in the clinic and through community-based and public health campaigns.
