Adherence to a healthier lifestyle was significantly associated with a lower risk of sudden cardiac death (SCD) in a new analysis from the Nurses’ Health Study.
The low-risk lifestyle factors included:

• no smoking,
• BMI <25,
• daily physical activity of at least 30 minutes, and
• consumption of a Mediterranean-type diet.

Each of these four lifestyle factors had an independent and statistically significant association with a lower risk of SCD. Analysis showed that the magnitude of the risk reduction increased with the number of low-risk factors, as compared with women who had none of the traits:

• 46% for one low-risk factor
• 59% for two
• 67% for three
• 92% for all four

This is absolutely huge news. So, if you don’t meet these four criteria, now’s the time to develop a strategy to meet all four. By the way, I suspect that getting your BMI to <27, having 30 minutes at least three days a week, and consuming the DASH diet would have very similar outcomes. So, that might be an easier set of goals to tackle first.
By the way, if you’d like to take an assessment that will help you evaluate your physical, emotional, relational, and spiritual health, here are two from my book, 10 Essentials of Happy, Healthy People: Becoming and staying highly healthy:

• Assess Your Health – Adult
  
• Assess Your Health – Christian Adult
  
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• Assess Your Health – Teens
  

Here are more details on this study from MedPage Today:

Women who adhered to a healthy lifestyle had as much as a 90% reduction in the risk of sudden cardiac death (SCD) as compared with those with a high-risk profile, data from the Nurses’ Health Study (NHS) showed.
Compared with women with none of the low-risk attributes, the risk of SCD declined linearly as the number of these attributes increased, ranging from a 46% reduction for a woman who had one to 92% for those who had all four.
About 80% of attributable risk for SCD was associated with the four lifestyle factors included in the analysis: smoking, overweight, inactivity, and poor diet, according to an article http://jama.ama-assn.org/content/306/1/62.short  in JAMA.
“In this cohort of female nurses, adherence to an overall healthy lifestyle was associated with a lower risk of SCD and may be an effective strategy for the prevention of SCD,” Stephanie E. Chiuve, ScD, of Harvard School of Public Health in Boston, and co-authors wrote in conclusion.
“Because SCD accounts for more than 50% of CHD mortality, widespread adoption of a healthy lifestyle in the population may make a substantial impact on reaching the American Heart Association’s 2020 Impact Goal of further lowering cardiovascular disease mortality.”
While most episodes of SCD occur in people who have underlying coronary heart disease (CHD), SCD is the first manifestation of CHD in the majority of people, especially women, the authors wrote in their introduction.
Primary prevention of SCD has focused on use of implantable cardioverter-defibrillators in patients with severe left ventricular dysfunction, but only a minority of SCD events occur in this high-risk group. Prevention strategies are needed to reduce SCD incidence in lower-risk populations, the authors continued.
Because several modifiable lifestyle factors are associated with SCD, Chiuve and colleagues examined the individual and cumulative impact of these factors on SCD risk in the NHS.
The analysis included 81,722 women ages 30 to 55 at enrollment and followed from June 1984 to June 2010. NHS participants completed lifestyle questionnaires every two to four years, beginning in 1984.
Investigators defined a low-risk lifestyle as no smoking, BMI <25, at least 30 minutes of exercise daily, and top 40% of the alternate Mediterranean diet score. The diet emphasizes consumption of vegetables, fruits, nuts, legumes, whole grains, and fish, and moderate alcohol consumption.
The authors found that 321 SCD events occurred during the 26 years of follow-up, involving women whose median age was 72 at the time of SCD.
Each of the four low-risk lifestyle factors had an independent, statistically significant association with a lower risk of SCD (P<0.001). Multivariable analysis showed that the magnitude of the risk reduction increased with the number of low-risk factors, as compared with women who had none of the traits:

• 46% for one low-risk factor
• 59% for two
• 67% for three
• 92% for all four

The authors determined that 81% of attributable SCD risk was related to smoking, inactivity, overweight, and poor diet. After exclusion of women with clinically diagnosed CHD, the attributable risk declined only slightly to 79%.
Women are 50% less likely compared with men to have severe left ventricular dysfunction and 66% less likely to have a CHD diagnosis prior to SCD, the authors noted in their commentary. Consequently, women are substantially less likely to meet current guidelines for use of preventive therapies, including ICDs.
“Prevention efforts that can be applied across broader populations, such as healthy lifestyle practices, are crucial to prevent SCD, particularly among women,” they wrote.
But the authors noted a number of limitations to their study, most of which can be traced back to their use of population attributable risk. Population attributable risk, they wrote, assumes a causal relationship between lifestyle and risk of SCD, an assumption the authors characterized as “large.”
They also noted that their population was mainly white health professionals.