Estimating the real-world effects of expanding antiretroviral treatment eligibility: Evidence from a regression discontinuity analysis in Zambia.
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ABSTRACT:
SUBMITTER: Mody A
PROVIDER: S-EPMC5988277 | biostudies-literature | 2018 Jun
REPOSITORIES: biostudies-literature
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Estimating the real-world effects of expanding antiretroviral treatment eligibility: Evidence from a regression discontinuity analysis in Zambia.
Mody Aaloke A Sikazwe Izukanji I Czaicki Nancy L NL Wa Mwanza Mwanza M Savory Theodora T Sikombe Kombatende K Beres Laura K LK Somwe Paul P Roy Monika M Pry Jake M JM Padian Nancy N Bolton-Moore Carolyn C Holmes Charles B CB Geng Elvin H EH
PLoS medicine 20180605 6
<h4>Background</h4>Although randomized trials have established the clinical efficacy of treating all persons living with HIV (PLWHs), expanding treatment eligibility in the real world may have additional behavioral effects (e.g., changes in retention) or lead to unintended consequences (e.g., crowding out sicker patients owing to increased patient volume). Using a regression discontinuity design, we sought to assess the effects of a previous change to Zambia's HIV treatment guidelines increasing ...[more]
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Project description:BackgroundUniversal testing and treatment (UTT) for all people living with HIV has only been assessed under experimental conditions in cluster-randomised trials. The public health effectiveness of UTT policies on the HIV care cascade under real-world conditions is not known. We assessed the real-world effectiveness of universal HIV treatment policies that were implemented in Zambia on Jan 1, 2017.MethodsWe used data from Zambia's routine electronic health record system to analyse antiretroviral therapy (ART)-naive adults who newly enrolled in HIV care up to 1 year before and after the implementation of universal treatment (ie, Jan 1, 2016, to Jan 1, 2018) at 117 clinics supported by the Centre for Infectious Disease Research in Zambia. We used a regression discontinuity design to estimate the effects of implementing UTT on same-day ART initiation, ART initiation within 1 month, and retention on ART at 12 months (defined as clinic attendance 9-15 months after enrolment and at least 6 months on ART), under the assumption that patients presenting immediately before and after UTT implementation were balanced on both measured and unmeasured characteristics. We did an instrumental variable analysis to estimate the effect of same-day ART initiation under routine conditions on 12-month retention on ART.Findings65 673 newly enrolled patients with HIV (40 858 [62·2%] female, median age 32 years [IQR 26-39], median CD4 count 287 cells per μL [IQR 147-466]) were eligible for inclusion in the analyses; 31 145 enrolled before implementation of UTT, and 34 528 enrolled after UTT. Implementation of universal treatment increased same-day ART initiation from 41·7% to 74·8% (risk difference [RD] 33·1%, 95% CI 30·5-35·7), ART initiation by 1 month from 69·6% to 87·0% (RD 17·4%, 15·5-19·3), and 12-month retention on ART from 56·2% to 63·3% (RD 7·1%, 4·3-9·9). ART initiation rates became more uniform across patient subgroups after implementation of universal treatment, but heterogeneity in 12-month retention on ART between subgroups was unchanged. Instrumental variable analyses indicated that same-day ART initiation in routine settings led to a 15·8% increase (95% CI 12·1-19·5) in 12-month retention on ART.InterpretationUTT policies implemented in Zambia increased the rapidity and uptake of ART, as well as retention on ART at 12 months, although overall retention on ART remained suboptimal. UTT policies reduced disparities in treatment initiation, but not 12-month retention on ART. Natural experiments reveal both the anticipated and unanticipated effects of real-world implementation and indicate the need for new strategies leveraging the short-term effects of UTT to cultivate long-term treatment success.FundingNational Institutes of Health.
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Project description:BackgroundIn the ATLANTIS study, second-line lurbinectedin/doxorubicin did not improve overall survival (OS), however patients with a chemotherapy-free interval (CTFI) of ≥180 days had an improved progression free survival (PFS). The objective of this retrospective study was to identify the proportion of real-world small cell lung cancer (SCLC) patients who are suitable for lurbinectedin-based therapy based on these criteria.MethodsA retrospective study of all SCLC referred to BC Cancer between 2012 and 2017 was conducted. Patient demographics, staging, treatment, and survival data were collected retrospectively. Baseline characteristics were compared using descriptive statistics. OS was calculated using Kaplan-Meier curves. Statistically significant p-value was <0.05.ResultsA total of 1048 patients were identified. Baseline characteristics: median age 68 years, 47% male, 61% current smoking status, 68% extensive disease. Best supportive care was received by 22%. First-line systemic therapy was platinum doublet for 71% of the population. Second-line systemic therapy was delivered to 22%. Of the 219 patients who received second-line systemic therapy after platinum doublet, 183 patients had a CTFI of ≥90 days and 107 patients had a CTFI of ≥180 days. Patients originally treated as limited stage disease, received platinum doublet as second line, received thoracic radiation (RT) or prophylactic cranial irradiation (PCI) were more likely to have a CTFI of ≥90 and ≥180 days.ConclusionIn our real-world SCLC population, only 21% of the SCLC population received second-line therapy after platinum doublet with 17% achieving CTFI of ≥90 days and 10% CTFI of ≥180 days. Based on this retrospective review, only a small fraction of platinum-treated patients would be preferentially offered lurbinectedin in the second-line setting.
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