高齢者非腫瘍性疾患の特徴―非腫瘍性消化管疾患の病理学的特徴

Pathological Characteristics of Gastrointestinal Non-neoplastic Lesions in the Elderly

要旨　高齢者の消化管には老化に伴う生理的変化と病的変化がみられる．この両者は基本的には区別されるべきものであるが，必ずしも明確に区別できないことも多いうえ，両者が複合的に病態を起こすこともある．消化管の生理的老化として，腺・筋層の萎縮，神経叢の機能低下が代表的変化であり，消化管の分泌機能の低下，蠕動運動や内圧の異常を生じうる．一方，腫瘍以外の病的変化として，動脈硬化に伴う虚血，Lewy小体病やアミロイドーシスをはじめとする全身疾患の一環としての変化，薬物の影響などが挙げられる．高齢者は一人で多くの疾患を抱える多病（polypathy）と言われる病態が恒常的に存在するので，一つの疾患の治療が，ほかの疾患の増悪因子となりうる．高齢者では，潰瘍，虚血などの変化に出血が伴いやすいこと，薬物の副作用が現れやすいことなどが病理学的特徴として挙げられる．これらの病態は直接死因に結びつく可能性があり，不測の事態に備え，予防的に診療に当たることが重要である．

　Both age-related physiological and pathological changes occur in the gastrointestinal（GI）tract in the elderly. Although both changes are basically different, it is sometimes difficult to distinguish between them. Both types of changes may be complicated and may induce diseases. Representative changes that are seen in physiological aging are glandular and muscular atrophies and abnormalities in peripheral nerve plexuses, which may induce dysfunction in secretion, internal pressure, and peristaltic movement of the GI tract. The following diseases are characteristic features as non-neoplastic lesions : atherosclerosis-associated ischemia, GI tract changes in systemic diseases such as Lewy body disease and amyloidosis, and the influence of various drugs. Since elderly patients may have multiple pathological conditions, treatment for a certain disease may cause deterioration in the symptoms related to another disease. Higher hemorrhagic tendency and a greater frequency of adverse effects of drugs are characteristic features of the GI tract in the elderly. These conditions may be a direct cause of death. Therefore, it is important to ensure that preventive measures are used to prevent such unexpected effects.