Rockville, MD - A new Swedish study looking at the benefit of a combination of several healthy lifestyle behaviors has found that most MIs in women could be prevented by consuming a healthy diet, being physically active, not smoking, and maintaining a healthy weight [1].

Dr Agneta Akesson (Karolinska Institute, Stockholm, Sweden) and colleagues report their findings in the October 22, 2007 issue of the Archives of Internal Medicine. They say there is little prior information on the benefit achieved with a combination of several healthy lifestyle behaviors. The results indicate that the combined benefit of diet, lifestyle, and healthy body weight "may prevent more than three of four cases of MI," they note.

"Our study shows the great effect you get from each of these and by combining them," Akesson told heartwire. "It's quite a simple health message, and you can do them by yourself."

The Swedish researchers say CHD risk-factor characterization and prevention in women need improvement, and despite the proven benefits of pharmacologic therapies, "diet and lifestyle largely influence morbidity and mortality in CHD."

One of the novel things the Swedish group did was to assess behavioral dietary patterns among the 24 444 postmenopausal women they studied, who were participating in the population-based prospective Swedish Mammography Cohort and who were free of diagnosed cancer, cardiovascular disease, and diabetes mellitus at baseline (September 15, 1997).

They identified four major dietary patterns: healthy (vegetables, fruits, and legumes); Western/Swedish (red meat, poultry, rice, pasta, eggs, fried potatoes); alcohol; and sweets (sweet baked goods, candy, chocolate). Those who consumed moderate amounts of alcohol (5 g or more a day; equivalent to a glass of wine every other day) were categorized as low risk. No upper limit for alcohol consumption was defined, because few women consumed high amounts of alcohol (less than 0.3% reported drinking more than 45 g/day). Those in the lowest-risk quintile for diet had an almost fourfold higher weekly consumption of vegetables and fruits, a threefold higher consumption of legumes, and a 70% higher consumption of fish compared with the highest-risk quintile.

During a mean of 6.2 years of follow-up, there were 308 incident cases of primary MI, of which 51 were fatal.

The researchers defined a low-risk dietary behavior based on high scores for the healthy dietary pattern (low-risk quintiles 3-5) and, when combined with moderate alcohol intake, this group had a significant 57% reduction in primary MI.

The researchers also defined three low-risk lifestyle factors: nonsmoking, waist/hip ratios less than the 75th percentile (<0.85), and being physically active.

The 5% of the study population who ate healthily, drank alcohol in moderation, and maintained these three low-risk lifestyle behaviors had a 92% decreased risk of MI compared with women without any low-risk diet and lifestyle factors.

The population-attributable risk in the study population, in which only 5% of the women fulfilled the criteria for the comprehensive low-risk behavior, was 77%, "which suggests that more than three of four of the coronary events could potentially be averted if all women would change their behavior to the low-risk profile," the researchers explain.

Akesson told heartwire that other studies have looked at MIs and diet, but many assessed only dietary behavior and did not include alcohol intake or the combination of these with other healthy lifestyle approaches. A similar study in the New England Journal of Medicine looking at the Nurses' Health Study did find a similar reduction in MI, she notes, although this used body-mass index rather than waist/hip ratio as a measure of obesity.

"Our results suggest that important steps can be taken to significantly reduce the risk of primary nonfatal CHD. Randomized trials are clearly preeminent to establish causality between both diet and lifestyle and CHD risk, but because randomized trials are difficult to perform for multiple risk factors, the combined low-risk behavior may never be able to be tested in primary-prevention trials. Therefore, prevention should build on best available information," they conclude.

US doctors writing in the same issue report that a high intake of whole-grain breakfast cereals is associated with a lower risk of heart failure in 21 376 men participating in the Physician's Health Study I [2]. Dr Luc Djousse (Harvard Medical School, Boston, MA) and colleagues say, "To our knowledge, this is the first study to prospectively examine the relation between breakfast-cereal consumption and the risk of HF in a large cohort."

They found that during an average follow-up of 19.6 years, 1018 incident cases of HF occurred. For average weekly cereal consumption of zero servings, one or fewer, two to six, and seven or more, hazard ratios for HF were 1 (reference), 0.92, 0.79, and 0.71 (p<0.001 for trend) after adjustment for multiple variables. The association was limited to the intake of whole-grain cereals but not refined cereals.

Djousse told heartwire that "doctors should be advocating the consumption of whole-grain rather than refined cereals, and these findings are consistent with the previous message that whole grain is good." He believes the beneficial effects of whole grains on reducing heart failure are mediated via their effects on blood pressure and lowering the risk of diabetes and coronary heart disease, "all of which are major risk factors for HF."

He cautioned, however, that these effects might have been exaggerated in this study, performed in "a highly educated group of mainly white men, with knowledge about the disease." The results need to be replicated in women and ethnic minorities and in the general population per se, without knowledge of heart disease, he said. In the meantime, he thought that there was no harm in eating products such as [whole-grain] pasta and bread and buying whole-grain products in general.