肺癌検診の経済評価

摘要

医療の経済分析は，医療費の抑制を目的とするものではなく，医療の無駄や判断のミスを防ぎ，より質の高い効率的な医療を実現するための意思決定の補助手段である．癌検診の評価は，その検査が安全かつ妥当なものであるか，発見や救命に効果があるかという視点に加えて，投じた費用に見合う成果がえられるかという経済的な評価が重要となる．癌臨床医を対象に行った調査では，癌の評価で経済面の重要度は15％（臨床面，QOL面，経済面の合討：100％）である．Markovモデルに準じて開発したシステムモデルでみると，肺癌検診で患者1人を発見するのに要する費用は40歳代男性で約5，220万円，50歳代で1，430万円であり，対象年齢の絞り込みは重要である．肺癌医療（検診＋治療）の費用対便益比は，男性の全年齢で1.14であり，肺癌医療は，投じられる費用にほぼ見合う経済効果，すなわち回復による労働生産性が得られていることがわかる．ただし，肺癌では，救命に寄与した費用は約1，100億円（2000年）であるのに対し，死亡したことで救命に寄与しえなかった費用は2，600億円と，両者の割合は1：3であり，肺癌の一次予防，早期発見は急務である．Economic evaluation in cancer screening is increasingly used to help clinicians and policy makers make sound and rational decisions.This is a useful tool that gives us the information on the effects of health programs and of alternative options in terms of their costs, consequences and benefits. This is to clarify the present and future relationship between the input resources and economic effects of lung cancer control programs for developing evidence-based health policy and for improving the quality of health services. We developed a system model of cancer prognosis, similar to the Markov Model, and analyzed the balance of patient labor productivity (Benefit) and accumulated cancer care costs including screening costs (Cost), Such parameters as distribution of stages, probability of progress, 5-year-survival and medical costs of survivors were collected for the model. The cost-benefit ratios, expected survival years, costs per QALYs, costs of lifesaving, "death rate" (mortality/morbidity) and also the simulated future changes were calculated in the model, It costs 2-4 times in the lung cancer screening for the age of 40' s in compared with that of 50' s.The proportion of in total expenditure in lung cancer control program will be approximately 30-40% even in 2010, while the relatively better result from 50 to 70% will be appeared in other cancers.lt was proven that the drastic increase of total medical costs in the future would hardly influence the balance itself.