July 21, 2008

Unhealthy Habits May Boost Eskimos’ Heart Risks

Photo of an older Native American Eskimo man Alaska Division of Tourism

A new study shows that Alaskan Eskimos have significantly higher rates of fatty deposits in their arteries than the general U.S. population, possibly because smoking rates are at least 3 times higher than average among adult Eskimos. The researchers suggest that smoking, saturated fats and other unhealthy choices may be impinging on the traditional, healthy lifestyles of Alaska natives.

Only 2 decades ago, researchers observed that Alaska Eskimos had historically low death rates from cardiovascular disease. Some attributed these low rates to the traditional Eskimo diet, rich in heart-healthy omega 3 fatty acids found in fish. But more recent studies are finding evidence that cardiovascular disease has been climbing in this population.

To look at the factors behind this shift, researchers funded by NIH’s National Heart, Lung and Blood Institute (NHLBI) have been collecting extensive medical and lifestyle data on more than 1,200 Eskimo adults. The latest results from this ongoing study—called the Genetics of Coronary Artery Disease in Alaska Natives Study—were published on July 10, 2008, in an advance online edition of Stroke.

The scientists examined participants’ medical records, including ultrasound scans of their carotid arteries, the neck arteries that carry blood to the brain. Ultrasound can detect signs of atherosclerosis—fatty buildup in arteries—before symptoms appear.

The investigators found that the thickness of the carotid arteries in the Alaska group was about the same as that seen in both African Americans and Caucasians of similar ages in another large NHLBI-funded study. However, the Alaska natives had significantly higher rates of atherosclerosis in their carotid arteries.

“Since atherosclerosis is a systemic disease, if you see it in one artery of the body, there is a high likelihood that it is also present in the coronary arteries,” says Dr. Mary J. Roman, a lead author of the study and a professor of medicine at Weill Cornell Medical College in New York.

Although the study found that participants consumed a healthy portion of omega-3 fatty acids each day, other factors seem to counteract any beneficial effect they might have. Smoking seems the most likely culprit. The researchers reported that about 63% of Eskimo men and 57% of women were current smokers, compared to about 24% of men and 18% of women in the general U.S. population. Smoking was strongly linked to atherosclerosis in the Alaska natives, especially in younger participants.

“The data in this report suggest that Alaskan Eskimos may have negated the protective effects of omega-3 fatty acids by increased rates of smoking and increased intake of saturated and trans fats,” says Roman. “This study is important because it is an observational, epidemiological look at a population that heretofore has not been studied in this manner.”

—by Vicki Contie