The effect of new cancer drug approvals on the life expectancy of American cancer patients, 1978-2004
The effect of new cancer drug approvals on the life expectancy of American cancer patients, 1978-2004
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DOI：
10.1080/10438590802547142
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发表时间：
2009-01-01
影响因子：
3.3
通讯作者：
Lichtenberg, Frank R.
中科院分区：
文献类型：
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作者：
Lichtenberg, Frank R.
这项研究试图确定在过去40年中引入的新癌症药物在多大程度上延长了被诊断患有癌症的美国人的生命。我们使用差异中的差异方法：我们分析癌症部位（乳腺癌，前列腺癌，肺癌等）之间的相关性。在以前诊断出患有癌症的人的危险率的变化和已经引入治疗癌症的药物数量的变化之间，控制可能反映诊断技术变化的变量：癌症分期分布，诊断时的年龄，诊断人数（发病率），以及手术和放射的使用。新的癌症药物的引入率在不同的癌症部位和不同的时间有很大的差异。使用国家癌症研究所（NCI）词库和Drugs@FDA数据库构建癌症部位特异性药物引入数据。所有其他变量的数据均来自NCI的监测、流行病学和最终结果9登记数据库，该数据库是美国癌症发病率和生存率的权威信息来源。我们发现，药物的滞后库存对癌症患者的风险率的影响是负的，非常显着。这意味着，在其他条件不变的情况下，批准药物滞后库存增加较大的癌症部位的风险率降低较大。美国食品和药物管理局（FDA）批准的库存对危险率的影响往往会在数年内稳步增加，在上市后约8-12年达到峰值，然后下降。这一发现与抗癌药物产品生命周期的证据相一致：在FDA批准后，利用率趋于稳定增长，在上市后约6-10年达到峰值，然后下降。癌症分期、诊断时的年龄和发病率变量对风险率有预期的影响。据估计，1968-1994年期间推出的新抗癌药物使癌症患者的预期寿命增加了近1年（0.94年）。虽然癌症患者的健康状况并不完美，但质量调整生命年的增长并不一定低于预期寿命的增长。由于一生中被诊断出患有癌症的风险约为40%，因此估计1978年至2004年癌症药物落后库存的增加使整个美国人口的预期寿命增加了0.38年。这相当于美国出生时预期寿命总体增长的8.8%。估计获得的每个生命年的成本不超过6908美元，这远远低于最近对统计生命年价值的估计。
This study attempts to determine the extent to which new cancer drugs introduced during the last 40 years have prolonged the lives of Americans diagnosed with cancer. We use a difference-in-differences approach: we analyze the correlation across cancer sites (breast, prostate, lung, etc.) between changes in the hazard rate of people previously diagnosed with that cancer and changes in the number of drugs that have been introduced to treat that cancer, controlling for variables likely to reflect changes in diagnostic techniques: cancer stage distribution, age at diagnosis, number of people diagnosed (incidence), and use of surgery and radiation. The rate of introduction of new cancer drugs varied considerably across cancer sites and over time. Data on cancer-site-specific drug introductions are constructed using the National Cancer Institute (NCI) Thesaurus and the Drugs@FDA database. Data on all other variables were obtained from the NCI's surveillance, epidemiology, and end results 9 Registries Database, an authoritative source of information on cancer incidence and survival in the USA. We find that the effect of the lagged stock of drugs on the hazard rate of cancer patients is negative and highly significant. This signifies that cancer sites with larger increases in the lagged stock of approved drugs had larger reductions in the hazard rate, ceteris paribus. The impact of the stock of Food and Drug Administration (FDA) approvals on the hazard rate tends to increase steadily for a number of years, peak about 8-12 years after launch, and then decline. This finding is consistent with evidence about the product life cycle of cancer drugs: utilization tends to increase steadily after FDA approval, peak about 6-10 years after launch, and then decline. The cancer stage, the age at diagnosis, and incidence variables have the expected effects on the hazard rate. New cancer drugs introduced during the period 1968-1994 are estimated to have increased the life expectancy of cancer patients by almost 1 year (0.94 years). Although the health of cancer patients is less than perfect, the increase in quality-adjusted life-years is not necessarily less than the increase in life expectancy. Since the lifetime risk of being diagnosed with cancer is about 40%, the 1978-2004 increase in the lagged stock of cancer drugs is estimated to have increased the life expectancy of the entire US population by 0.38 years. This represents about 8.8% of the overall increase in US life expectancy at birth. Estimated cost per life-year gained does not exceed $6908, which is far below recent estimates of the value of a statistical life-year.