Crohn病における長期経過―経過良好例（non-disabling disease）の予測

Long-term Clinical Course and Prognosis of Patients with Crohn's Disease

要旨　Crohn病の長期経過例(発症から15年以上経過例)221例を対象に，その経過・予後を検討した．バイアスのない解析とするために，解析経過観察中の症例(follow up群)のみでなく，経過観察中でない症例(non-follow up群)も可能な限り追跡した．特定疾患医療受給者の臨床調査個人表に記載されている項目を中心に，長期経過を経過良好群と経過不良群のいずれかに判定した．さらに，経過良好群の予測因子を知るために，両群間で診断時の患者背景，病型，各種検査値および活動指数，X線および内視鏡所見による罹患部位や病変の重症度を比較検討した．経過検討可能例は，221例中187例(84.6％)で，経過良好群は，53例(28.3％)，経過不良群が134例(71.7％)であった．経過良好群，不良群との診断時項目の比較では，発症年齢が経過不良群で有意に低く，病型では小腸大腸型が経過不良群に，アフタのみ，大腸型は経過良好群に多かった．活動指数IOIBD，CDAIはともに不良群が有意に高く，病初期の活動性が経過・予後に影響する因子と考えられた．X線，内視鏡検査の検討にて，罹患部位では，空腸，上部回腸病変の存在と程度が，病変形態では，小腸は，縦走潰瘍，敷石像，大腸は敷石像の重症度が経過・予後に関与していた．以上の結果から，Crohn病の約3割は長期の経過・予後が良好であり，診断時の病型，活動指数，形態学的所見で，経過・予後の予測がある程度可能と考えられた．

　The aim of this study is to clarify long-term clinical course, prognosis and prognostic factors of patients with Crohn's disease (CD). 221 patients with CD whose clinical course had continued for 15 years after onset were studied. For an analysis without bias, not only those patients currently under observation at our hospital (the follow-up groups), but also those not being observed (non-follow-up group) were investigated as for a possible. We classified these patients into two prognosis groups (good, bad) according to the evaluation of their whole clinical course. We evaluated their clinical course and prognosis mainly based on the contents of the individual clinical survey sheet that was designed by the Ministry of Health, Labor and Welfarefor. In addition, to clarify the factors influencing the prognosis of patients with CD, we compared the clinical backgrounds of these two groups', including disease type, laboratory data, disease activity indices, radiographic and endoscopic findings at the time of diagnosis. Among the 221 patients, 187 (84.6％) were able to be observed during their clinical course. 53 patients (28.3％) were in the good prognosis group and 104 patients (71.7％) were in the bad prognosis group. According to analysis of comparisons between the two groups, the age of onset of the bad prognosis group was significantly younger than that of the good prognosis group. For disease types, ileo-colitis type was dominant in the bad prognosis group and aphthous type and colitis type were frequent findings in the good one. Both activity indices, IOIBD and CDAI, were significantly higher in the bad group, suggesting that the conditions at the early stage of the disease are the factors affecting the clinical course and prognosis. In the evaluation by radiographic and endoscopic findings, the following were suspected to be involved in the clinical course and prognosis：the presence and extent of the lesions involving the jejunum and upper ileum；and the severity of longitudinal ulcers of the small intestine and the severity of cobblestone appearance of both the small and large intestine. These findings indicated that the results of a long-term clinical observation and prognosis are satisfactory in approximately 30％ of the cases with CD in Japan. We also speculated that young age, disease type, activity indices and morphological findings at diagnosis are able to be predictive factors of the clinical course and prognosis of patients with CD, but larger numbers and multi-center studies are necessary to verify these results.