著者

辻 一郎

出版者

The Japan Stroke Society

雑誌

脳卒中 (ISSN:09120726)

巻号頁・発行日

vol.24, no.3, pp.344-348, 2002

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Based on the currently available evidence, we estimated cost-effectiveness of brain check-up with MRI/ MRA to diagnose and treat asymptomatic unruptured cerebral aneurysm.<BR>In this simulation analysis using a medical decision analysis model, we estimated costs and effectiveness under two different strategies ; one is asymptomatic 100, 000 Japanese population, aged mid-50's, receive brain check-up (Screen group), and another is nobody receive brain check-up (No Screen group). Costs included those for brain check-up (JPY 30, 000), diagnostic work-up (JPY 200, 000), treatment of unruptured aneurysm (JPY 2, 000, 000), treatment of ruptured aneurysm (JPY 4, 000, 000), and for long-term care ranging from JPY 1, 000, 000 to 5, 000, 000 per year according to the severity of disability. Effectiveness of brain check-up, in this analysis, was defined as the gain of life-years of survival, which is calculated as the difference of total life-years between the Screen group and the No Screen group.<BR>Based on the currently available evidence in Japan, we assumed the prevalence of asymptomatic unruptured aneurysm in the Japanese population aged mid-50's as 5%, sensitivity of brain check-up as 87%, its specificity as 92%. Likewise, we estimated the distribution of aneurysm size and the probability of spontaneous rupture according to the size, and the life and functional prognosis of the cases (see Text).<BR>The results indicated that mortality from subarachnoid hemorrhage would be decreased in the Screen group by about 80% than in the No Screen group. The cost for saving the life of one case with asymptomatic unruptured aneurysm was estimated to be JPY 74.4 × 10<SUP>6</SUP>, and the cost for one life-year suvival was estimated to be JPY 2.4×10<SUP>6</SUP>.