AHAが琉球大研究紹介、指先血流が30％増加
2013年12月3日 米国学会短信
カテゴリ： 循環器疾患・内分泌・代謝疾患・検査に関わる問題
米国心臓協会（AHA）は11月20日、コーヒーの摂取で小血管の血行が改善することを示した研究を紹介した。同学会年次集会で発表。
この研究の被験者は、コーヒーを常飲していない健康者（22-30歳）27人。レギュラーまたはカフェインレスコーヒーを1回（約150mL）摂取後、レーザードップラー血流計による指先の血流量、血圧、心拍数、血管抵抗度を測定した。また、採血により血中カフェイン濃度を測定。併せて血管機能に影響を及ぼすホルモンの作用を除外した。2日後、同じ被験者についてレギュラーとカフェインレスを入れ替えて、同様の測定を行った。
レギュラーコーヒー摂取群はカフェインレスコーヒー摂取群に比べ、指先の血流が75分間にわたり30％増加。血圧のわずかな上昇、血管内壁の機能の軽度改善も認めた。心拍数は両群で差がなかった。
「カフェインがどのように血管機能を改善するかは不明だが、血管の開通や炎症の軽減に役立っている可能性がある。コーヒーが持つ好ましい効果の機序が解明されれば、循環器疾患に対する新しい治療法が生まれるかもしれない」と、研究を行った琉球大学の研究者は述べている。
Coffee may help perk up your blood vessels
American Heart Association Meeting Report: Abstract 12428 (Hall F, Core 7, Poster Board: 7062)
November 20, 2013
Study Highlights:
•A small study showed that a cup of coffee improved small blood vessel function.
•The study takes us one step closer to understanding how coffee might benefit cardiovascular health.
Embargoed until 9:30 a.m. CT/10:30 a.m. ET Wed., Nov. 20, 2013
DALLAS, Nov. 20, 2013 – The caffeine in a cup of coffee might help your small blood vessels work better, according to research presented at the American Heart Association’s Scientific Sessions 2013.
A study of 27 healthy adultsshowed – for the first time – that drinking a cup of caffeinated coffee significantly improved blood flow in a finger, which is a measure of how well the inner lining of the body’s smaller blood vessels work. Specifically, participants who drank a cup of caffeinated coffee had a 30 percent increase in blood flow over a 75-minute period compared to those who drank decaffeinated coffee.
“This gives us a clue about how coffee may help improve cardiovascular health,” said Masato Tsutsui, M.D., Ph.D., lead researcher and a cardiologist and professor in the pharmacology department at the University of the Ryukyus in Okinawa, Japan.
The study adds to a growing body of research about coffee, the most widely consumed beverage worldwide. Previous studies showed that drinking coffee is linked to lower risks of dying from heart disease and stroke, and that high doses of caffeine may improve the function of larger arteries.
Study participants were people who did not regularly drink coffee, ranging in age from 22 to 30. On one day, each participant drank one five-ounce cup of either regular or decaffeinated coffee. Then researchers measured finger blood flow with laser Doppler flowmetry, a non-invasive technique for gauging blood circulation on a microscopic level. Two days later, the experiment was repeated with the other type of coffee. Neither the researchers nor the participants knew when they were drinking caffeinated coffee.
The researchers noted blood pressure, heart rate, and vascular resistance levels. They also took blood samples to analyze levels of caffeine and to rule out the role of hormones on blood vessel function.
Compared to decaf, caffeinated coffee slightly raised participants’ blood pressure and improved vessel inner lining function. Heart rate levels were the same between the two groups.
It’s still unclear how caffeine actually works to improve small blood vessel function, although Tsutsui suggests that caffeine may help open blood vessels and reduce inflammation.
“If we know how the positive effects of coffee work, it could lead to a new treatment strategy for cardiovascular disease in the future,” said Tsutsui.
Co-authors are Katsuhiko Noguchi, Ph.D.; Toshihiro Matsuzaki, M.D., Ph.D.; Mayuko Sakanashi, Ph.D.; Naobumi Hamadate, Ph.D.; Taro Uchida; B.Sc.; Mika Kina-Tanada, D.D.S.; Haruaki Kubota,
M.D.; Junko Nakasone, Ph.D.; Matao Sakanashi, M.D., Ph.D.; Fumihiko Kamezaki, M.D., Ph.D.;
Akihide Tanimoto, M.D., Ph.D.; Nobuyuki Yanagihara, Ph.D.; Yusuke Ohya, M.D., Ph.D.; Hiroaki Masuzaki, M.D., Ph.D.; and Shogo Ishiuchi, M.D., Ph.D.
Author disclosures are on the abstract.
The study was funded in part by the All Japan Coffee Association.
Downloadable video/audio interviews, B-roll, animation and images related to this news release are on the right column of the release link at
http://newsroom.heart.org/news/coffee-may-help-perk-up-your-blood-vessels?preview=744c93c19f22229f53b80cd332c89853.
Video clips with researchers/authors of the studies will be added to the release link after embargo.
For more news from AHA Scientific Sessions 2013 follow us on Twitter @HeartNews #AHA13.
Statements and conclusions of study authors that are presented at American Heart Association scientific meetings are solely those of the study authors and do not necessarily reflect association policy or position. The association makes no representation or warranty as to their accuracy or reliability. The association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific association programs and events. The association has strict policies to prevent these relationships from influencing the science content. Revenues from pharmaceutical and device corporations are available at www.heart.org/corporatefunding.
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