Department of Health Services Research and Policy, Faculty of Public Health and Policy, London School of Hygiene and Tropical Medicine, London, United Kingdom.
Int J Cancer. 2012 Jul 15;131(2):E96-104. doi: 10.1002/ijc.26472. Epub 2011 Nov 9.
Due to the recent widespread availability of highly active antiretroviral therapy (HAART) in middle-income countries, there has been an increase in life expectancy for women on HAART, but no corresponding decrease in cervical cancer incidence. This study evaluates the optimal cervical cancer screening strategy for HIV-infected women in a middle-income country. We developed a mathematical model, which simulates the natural history of the HPV infection, as well as the HIV-mediated immunosupression among women in Brazil. Our model was calibrated using data from the IPEC/FIOCRUZ Women's HIV-infected cohort. The model compares the lifetime effects, costs and cost-effectiveness of strategies combining cytology, HPV DNA test and colposcopy at different screening intervals for different CD4 count strata (27 strategies in total). We found that the strategy with the best cost-effectiveness profile (cost-effectiveness ratio-U$4,911/year of life saved [YLS] and probability of being cost-effective-86%) was HPV testing followed by cytology triage every year for all HIV infected women, considering a very cost-effective threshold given by Brazil's GDP per capita (US$8,625/YLS). The results were robust to changes in the input parameters as demonstrated in one-way, scenario, threshold and probabilistic sensitivity analysis. Our study indicates that annual HPV testing followed by cytology triage for all HIV-infected women is likely to be very cost-effective in a middle-income country like Brazil. The results reflect the synergic effect of using a highly sensitive screening test (HPV DNA test) in sequence with a highly specific test (cytology).
由于在中等收入国家中，高效抗逆转录病毒疗法（HAART）的广泛应用，接受 HAART 的女性的预期寿命有所延长，但宫颈癌的发病率并没有相应下降。本研究评估了在中等收入国家中对 HIV 感染女性的最佳宫颈癌筛查策略。我们开发了一个数学模型，该模型模拟了 HPV 感染的自然史，以及巴西女性中 HIV 介导的免疫抑制。我们的模型使用 IPEC/FIOCRUZ 妇女 HIV 感染队列的数据进行了校准。该模型比较了不同 CD4 计数分层（共 27 种策略）下，不同筛查间隔的细胞学、HPV DNA 检测和阴道镜检查相结合的策略的终生效果、成本和成本效益。我们发现，在考虑到巴西人均 GDP（每 YLS 8625 美元）给出的非常具有成本效益的阈值时，具有最佳成本效益特征（成本效益比-U$4911/年 YLS 和 86%的成本效益概率）的策略是对所有 HIV 感染女性进行每年一次的 HPV 检测，然后对细胞学进行分流。单向、情景、阈值和概率敏感性分析表明，结果具有稳健性。我们的研究表明，在巴西等中等收入国家，对所有 HIV 感染女性进行每年一次的 HPV 检测，然后对细胞学进行分流，可能具有很高的成本效益。结果反映了使用高度敏感的筛查试验（HPV DNA 检测）与高度特异性试验（细胞学）相结合的协同效应。
