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Thursday, November 26, 2009

Atherosclerosis in Mummies 3500 Years Old: need to look beyond traditional risk factors.


Checking in on some very old patients with cutting-edge computed tomographic (CT) technology reveals that atherosclerosis might not necessarily be a disease caused by a modern lifestyle. Imaging scans of Egyptian mummies, including some 3500 years old, reveals evidence of atherosclerosis, report researchers.
"There were parts of the cardiovascular system [amazingly] intact," said researcher Dr Randall Thompson(University of Missouri-Kansas City School of Medicine). "We found that on CT scan, atherosclerosis, the disease that we deal so much with, looks surprisingly like it does in our modern-day patients."
Presenting their findings here at the American Heart Association 2009 Scientific Sessions last week, Thompson, along with coinvestigator Dr Sam Wann (Wisconsin Heart Hospital, Milwaukee), said the mummies included in the study all had high social status and many served in the court of the Pharaoh or as priests or priestesses. He added that the group had not expected to see any signs of cardiovascular disease because atherosclerosis is traditionally thought of as a disease caused by an unhealthy fast-food diet, smoking, and lack of exercise. This study, however, suggests the need to look beyond traditional risk factors.
"It looks like people 3000 years ago had the propensity, at least under the circumstances of living in the King's court, to develop this disease," said Wann.
The Mummy and the Skeptical Cardiologist
During a media briefing at the AHA last week, researchers said that the study began when Dr Gregory Thomas(University of California, Irvine), another member of the team, was touring the Museum of Egyptian Antiquities in Cairo last year and came upon Pharaoh Merenptah (c. 1213-1203 BCE). Information on the Pharaoh's nameplate stated that he died at approximately age 60 and was afflicted with atherosclerosis. Skeptical that someone who lived so long ago would have atherosclerosis, American and Egyptian researchers initiated the study to determine if the diagnosis was correct and, if it was, to determine how common atherosclerosis was in a small sample of ancient Egyptians.
Working with Dr Adel Allam (Al Azhar Medical School, Cairo, Egypt) and Dr Michael Miyamoto (University of California, San Diego), as well as with archeologists and mummy experts, in February 2009, the researchers scanned 22 mummies, the oldest of which was 3500 years old. The coronary, aortic, and peripheral vasculature was identified in 16 of the specimens. Definite or probable atherosclerosis was present in nine of the 16 mummies, but among those who were 45 years or older when they died, atherosclerosis was present in 87%.
The most ancient mummy with evidence of atherosclerosis was Lady Rai, a nursemaid to Queen Amrose Nefertari. Lady Rai died in 1530 BCE at an estimated age of 30 to 40 years; she had definite disease in her aortic arch.
At the AHA last week, Thompson and Wann noted that members of the Egyptian upper classes were meat eaters, and their diets would have included cattle, geese, and ducks. Lack of refrigeration, however, meant that many of these meats would have been heavily salted to prevent spoiling, and this might have led some individuals to develop high blood pressure. Although the exact reasons for the calcified build-up in the arteries is unknown, researchers said the results challenge the view that atherosclerosis is a disease of modern humans.
"This disease has been around since the time of Moses; it's as old as the Pyramids," said Thompson.
Source:  November 18, 2009 issue of the Journal of the American Medical Association.

Method of Fish Preparation Affects Cardiac Benefits

The cardioprotective effects of omega-3 fatty acids from fish consumption vary by ethnicity and method of preparation, a new study suggests. This is likely because of the types of fish consumed and the preparation methods used by different cultures, say the researchers.

Although the amount of fish consumed was key--along with whether it was high in omega-3 fatty acids, as is wild salmon and tuna--the results also indicate an important role for the method of cooking.

Those consuming adequate amounts of baked or boiled fish had lower rates of coronary heart disease (CHD) mortality during follow-up than those eating little fish. But those eating deep fried fish every day actually had higher mortality, as did those consuming salted or dried fish, she noted. The only method of frying fish that seemed protective was stir-frying, used primarily by the Japanese.

"Our findings suggest the method of preparation of fish may modify the protective effect of omega-3 fatty acids. The results can help educate people on how much fish to eat and how to cook it to prevent heart disease," Meng said. "If you want to eat fried fish, do it occasionally, but try to avoid it. Or eat it the Japanese way and stir fry it."

23% Reduction in Heart Disease Among Men Who Ate the Most Fish

Meng said that CHD mortality is known to differ by ethnicity in Hawaii, and that the disparities are not fully accounted for by known risk factors. She and her colleagues examined the source, type, amount, and frequency of dietary omega-3 consumption among participants in the Multiethnic Cohort (MEC) Study living in Los Angeles, CA and Hawaii. The cohort consisted of more than 80 000 men and 100 000 women of African American, Caucasian, Japanese, Native Hawaiian, and Latino descent, aged 45-75 years at recruitment, which occurred from 1993 to 1996; those with a history of myocardial infarction or angina were excluded. Food frequency questionnaires were used to examine fish consumption and omega-3 intake from other sources, such as plant materials like soy sauce.

The fact that the different ethnic groups in the MEC study have different sources of omega-3 provides a unique opportunity to look at this issue, and also to examine ethnic-specific data on methods of fish preparation, she said.

During an average of almost 12 years of follow-up, there were 2604 male and 1912 female deaths due to CHD.

Among men, those in the highest quintile (consuming a median of 3.3 g of dietary omega-3 fatty acids per day) had a 23% lower CHD mortality than those in the lowest quintile (median, 0.8 g per day), Meng said.

The benefits of omega-3 were more apparent in white, Japanese, and Latino men than in African Americans and native Hawaiians, she noted.

12%-15% Increase in CHD Death With Deep Fried, Salted, and Dried Fish

But these benefits were confined to raw fish or fish prepared by boiling or baking, she noted. Among both men and women, consumption of more than 6.2 g of deep fried fish per day (excluding stir-fried fish) led to a 12% increase in CHD mortality, Meng stressed, and even smaller amounts of salted or dried fish daily upped mortality by 15%. This latter effect could be due to the amount of sodium found in fish prepared in this way, she said.

Among men, Japanese ate the most fried fish, but they tended to prepare it by stir-frying, which does not seem to have the same risk as deep frying, Meng said. Second in consumption of fried fish were native Hawaiians, who also ate the most salted and dried fish, followed by African Americans.

Among women in general, the relation between fish consumption and mortality was "all in a protective direction," Meng said, but there was not as strong a dose-response as for men. Plant sources of omega-3, such as soy sauce and tofu, were particularly protective for women, she said, stressing that low-sodium products are best.

Source: http://www.medscape.com/viewarticle/713037

Thursday, November 5, 2009

Mediterranean Diet Delays the Need for Drug Therapy in Type 2 Diabetes

Effects of a Mediterranean-Style Diet on the Need for Antihyperglycemic Drug Therapy in Patients With Newly Diagnosed Type 2 Diabetes: A Randomized Trial

Esposito K, Maiorino MI, Ciotola M, et al
Ann Intern Med. 2009;151:306-314

Study Summary

In this randomized controlled trial, 108 subjects with newly diagnosed type 2 diabetes were assigned to a Mediterranean-style diet (MED) while 107 were assigned to a low-fat diet based on American Heart Association guidelines. The MED diet was rich in vegetables and whole grains, low in red meat, had a goal of no more than 50% of calories from complex carbohydrates, and no less than 30% of calories from fat (mainly olive oil). The low-fat diet was rich in whole grains with the goal of no more than 30% of calories from fat and no more than 10% of calories from saturated fat. Both diets restricted energy intake to 1800 calories per day for men and 1500 for women, and each group received equal guidance on increasing physical activity. Subjects were followed for up to 4 years to assess the primary outcome of time to introduction of antihyperglycemic drug therapy. Per protocol, drug therapy was initiated when HbA1c exceeded 7% at 2 consecutive 3-month intervals. Secondary outcome measures included changes in weight, glycemic control, lipid levels, and blood pressure.
Typical of newly diagnosed patients, the study participants averaged 52 years of age, half were men, mean body mass index was about 30 kg/m2, and HbA1c was 7.7%. None of these characteristics differed between groups. At the end of the trial, 44% of MED subjects required antihyperglycemic drugs compared with 70% of low-fat diet subjects. The hazard ratio for time to drug therapy was 0.63 (95% confidence interval, 0.51-0.86), a finding that was essentially unchanged after adjustment for change in body weight. Both groups lost weight, and though the MED group lost significantly more in the first year, there was not a statistically significant difference between groups at the end of the trial. Other measures of glycemic control (changes in level of HbA1c, plasma glucose, serum insulin, HOMA insulin sensitivity, and adiponectin) all favored the MED participants. High-density lipoprotein (HDL) cholesterol increased and triglycerides decreased significantly more in the MED group.
Source: http://www.medscape.com/viewarticle/711007?src=mp&spon=22&uac=82830HJ

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