(c) flickr & NomadicPhoto
若い時に虫垂炎（盲腸）や扁桃炎の手術を受けると，後に心臓発作を起こす可能性が高くなることが明らかとなった。この研究では，1955年から1970年に生まれた全スウェーデン住民の医療記録から，20歳未満で虫垂または扁桃を除去した人がその後23.5年間に心臓発作を起こしたかどうか調査された。その結果，虫垂除去術は心臓発作のリスクを33%，扁桃除去術は44%上昇させることが分かった。両方の除去はリスクをさらに上昇させた。虫垂と扁桃はリンパ器官であり，それらの除去は長期的に免疫機能に影響すると考えられている。（吉田素子）
Increased Risk of Heart Attack after Early Removal of Appendix or Tonsils
Surgical removal of the tonsils or appendix in young people is associated with an increased relative risk of early heart attack, according to a novel study by researchers at Karolinska Institutet.
The study, which is published online in the European Heart Journal, examined the national health records of every Swedish resident born between 1955 and 1970 and identified each one who had had tonsils and/or appendix removed. Each of these patients was then matched with five randomly chosen controls which had not had the operations. These subjects were then followed up through the health records for an average of 23.5 years to cross-check for the occurrence of fatal or non-fatal heart attack. Because the appendix and tonsils appear to have reduced function after adolescence, the primary analyses were restricted to individuals below the age of 20 at the time of surgery, which amounted to 54,449 appendectomies and 27,284 tonsillectomies.
The results showed that surgical removal of the appendix and tonsils before the age of 20 was associated with an increased risk of premature heart attack. Tonsillectomy increased the risk by 44 percent and appendectomy by 33 percent. The risk increases were statistically significant, and were even higher when the tonsils and appendix were both removed. However, there was no risk association evident when operations were performed in people over the age of 20.
-- One must also remember that the absolute risk differences between subjects and control groups in the study were small, because of the young age of the participants, says Staffan Ahnve, Professor of Cardiovascular Medicine and Prevention, who led the study.
［単語和訳］
Heart Attack：心臓発作 Removal：除去 Appendix：虫垂 Tonsils：扁桃
Surgical：外科的な is associated with：～と関連している relative risk：相対リスク according to：～によると researchers：研究者
is published online：オンラインで発表される Swedish：スウェーデンの randomly：無作為に controls：対照 subjects：被験者 were followed up：追跡調査された cross-check：照合する occurrence：発生 fatal：致死的な adolescence：青年期 primary analyses：主要解析 were restricted：制限された surgery：手術 amounted to：合計～になった appendectomies：虫垂切除術 tonsillectomies：扁桃摘出術
premature：早期の statistically significant：統計学的に有意な
absolute risk：絶対リスク participants：参加者 Cardiovascular Medicine：心血管医学 Prevention：予防
