Department of Medicine, University of California San Francisco, San Francisco, California, United States of America.
PLoS One. 2009 Sep 29;4(9):e7196. doi: 10.1371/journal.pone.0007196.
We hypothesized that the percent adherence to antiretroviral therapy necessary to maintain HIV suppression would decrease with longer duration of viral suppression.
Eligible participants were identified from the REACH cohort of marginally housed HIV infected adults in San Francisco. Adherence to antiretroviral therapy was measured through pill counts obtained at unannounced visits by research staff to each participant's usual place of residence. Marginal structural models and targeted maximum likelihood estimation methodologies were used to determine the effect of adherence to antiretroviral therapy on the probability of virologic failure during early and late viral suppression.
A total of 221 subjects were studied (median age 44.1 years; median CD4+ T cell nadir 206 cells/mm(3)). Most subjects were taking the following types of antiretroviral regimens: non-nucleoside reverse transcriptase inhibitor based (37%), ritonavir boosted protease inhibitor based (28%), or unboosted protease inhibitor based (25%). Comparing the probability of failure just after achieving suppression vs. after 12 consecutive months of suppression, there was a statistically significant decrease in the probability of virologic failure for each range of adherence proportions we considered, as long as adherence was greater than 50%. The estimated risk difference, comparing the probability of virologic failure after 1 month vs. after 12 months of continuous viral suppression was 0.47 (95% CI 0.23-0.63) at 50-74% adherence, 0.29 (CI 0.03-0.50) at 75-89% adherence, and 0.36 (CI 0.23-0.48) at 90-100% adherence.
The risk of virologic failure for adherence greater than 50% declines with longer duration of continuous suppression. While high adherence is required to maximize the probability of durable viral suppression, the range of adherence capable of sustaining viral suppression is wider after prolonged periods of viral suppression.
我们假设，为了维持 HIV 抑制，所需的抗逆转录病毒治疗依从率将随着病毒抑制时间的延长而降低。
从旧金山边缘性住房 HIV 感染成人的 REACH 队列中确定了符合条件的参与者。通过研究人员在每个参与者的常住地进行的非预先通知访问中获得的药丸计数来测量抗逆转录病毒治疗的依从性。使用边际结构模型和靶向最大似然估计方法来确定抗逆转录病毒治疗依从性对早期和晚期病毒抑制期间病毒学失败概率的影响。
共研究了 221 名受试者（中位年龄 44.1 岁；中位 CD4+T 细胞最低点 206 个细胞/mm³）。大多数受试者正在服用以下类型的抗逆转录病毒方案：非核苷类逆转录酶抑制剂为基础（37%）、利托那韦增强蛋白酶抑制剂为基础（28%）或未增强蛋白酶抑制剂为基础（25%）。比较刚刚达到抑制后与连续 12 个月抑制后失败的概率，我们考虑的每个依从比例范围内，只要依从性大于 50%，病毒学失败的概率就会有统计学意义的降低。在 50-74%的依从率下，比较 1 个月和 12 个月连续病毒抑制后病毒学失败的风险差异为 0.47（95%CI 0.23-0.63），在 75-89%的依从率下为 0.29（CI 0.03-0.50），在 90-100%的依从率下为 0.36（CI 0.23-0.48）。
对于依从性大于 50%的患者，病毒学失败的风险随着持续抑制时间的延长而降低。虽然需要高依从性来最大限度地提高持久病毒抑制的概率，但在病毒抑制时间延长后，能够维持病毒抑制的依从性范围更广。
