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特集 生物学的精神医学の進歩
統合失調症の生物学的研究
著者： 笠井清登1 吉川茜1 夏堀龍暢1 小池進介1 永井達哉1 荒木剛2 西村幸香1 岩本和也3
所属機関： 1東京大学大学院医学系研究科精神医学分野 2東京大学大学院医学系研究科ユースメンタルヘルス講座 3東京大学大学院医学系研究科分子精神医学講座
ページ範囲：P.109 - P.118
文献概要
はじめに
統合失調症は，思春期以降に知覚過敏などの微細な精神症状を呈する前駆期を経て，幻覚妄想状態で顕在発症し，陰性症状を伴いながら進行性の経過をたどる慢性精神疾患である。罹患率は人種，民族によらずほぼ一定で約1％と高く，その損失は本人および家族の心理的，社会的苦痛に加え，障害調整生命年（Disability Adjusted Life Years：DALYs）などにあらわされるように経済社会的損失も計り知れない。発症には複数の遺伝要因と環境要因が複雑に絡み合うと考えられているが，病因はいまだ明らかではない。このため，中間表現型解析や適切な動物モデルを用いた研究の必要性が喚起されている。
近年では，分子遺伝学・神経生理学手法の飛躍的な進歩や脳画像解析技術の目覚ましい発展により，統合失調症の分子病態が次々と明らかにされている。2010年『Nature』誌巻頭言では，「A decade for psychiatric disorders」として1)，従来の研究手法に加え，心理社会的支援など多方面からのアプローチによって，科学的根拠に基づいた早期支援や発症予防を目指す新たな局面に移っているとしている2)。本稿では，近年の統合失調症研究における主要な研究成果を概説し，今後の展望を議論した。
統合失調症は，思春期以降に知覚過敏などの微細な精神症状を呈する前駆期を経て，幻覚妄想状態で顕在発症し，陰性症状を伴いながら進行性の経過をたどる慢性精神疾患である。罹患率は人種，民族によらずほぼ一定で約1％と高く，その損失は本人および家族の心理的，社会的苦痛に加え，障害調整生命年（Disability Adjusted Life Years：DALYs）などにあらわされるように経済社会的損失も計り知れない。発症には複数の遺伝要因と環境要因が複雑に絡み合うと考えられているが，病因はいまだ明らかではない。このため，中間表現型解析や適切な動物モデルを用いた研究の必要性が喚起されている。
近年では，分子遺伝学・神経生理学手法の飛躍的な進歩や脳画像解析技術の目覚ましい発展により，統合失調症の分子病態が次々と明らかにされている。2010年『Nature』誌巻頭言では，「A decade for psychiatric disorders」として1)，従来の研究手法に加え，心理社会的支援など多方面からのアプローチによって，科学的根拠に基づいた早期支援や発症予防を目指す新たな局面に移っているとしている2)。本稿では，近年の統合失調症研究における主要な研究成果を概説し，今後の展望を議論した。
参考文献
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