Shrinkage averaging estimation
In: Statistical papers, Band 53, Heft 4, S. 1015-1034
ISSN: 1613-9798
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In: Statistical papers, Band 53, Heft 4, S. 1015-1034
ISSN: 1613-9798
In: Statistical papers, Band 61, Heft 5, S. 2221-2240
ISSN: 1613-9798
In: Springer-Lehrbuch
In: Journal of the International AIDS Society, Band 18, Heft 1
ISSN: 1758-2652
IntroductionRoutine viral load (VL) monitoring is utilized to assess antiretroviral therapy (ART) adherence and virologic failure, and it is currently scaled‐up in many resource‐constrained settings. The first routine VL is recommended as late as six months after ART initiation for early detection of sub‐optimal adherence. We aimed to assess the optimal timing of first VL measurement after initiation of ART.MethodsThis was a retrospective, cohort analysis of routine monitoring data of adults enrolled at three primary care clinics in Khayelitsha, Cape Town, between January 2002 and March 2009. Primary outcomes were virologic failure and switch to second‐line ART comparing patients in whom first VL done was at three months (VL3M) and six months (VL6M) after ART initiation. Adjusted hazard ratios (aHR) were estimated using Cox proportional hazard models.ResultsIn total, 6264 patients were included for the time to virologic failure and 6269 for the time to switch to second‐line ART analysis. Patients in the VL3M group had a 22% risk reduction of virologic failure (aHR 0.78, 95% CI 0.64–0.95; p=0.016) and a 27% risk reduction of switch to second‐line ART (aHR 0.73, 95% CI 0.58–0.92; p=0.008) when compared to patients in the VL6M group. For each additional month of delay of the first VL measurement (up to nine months), the risk of virologic failure increased by 9% (aHR 1.09, 95% CI 1.02–1.15; p=0.008) and switch to second‐line ART by 13% (aHR 1.13, 95% CI 1.05–1.21; p<0.001).ConclusionsA first VL at three months rather than six months with targeted adherence interventions for patients with high VL may improve long‐term virologic suppression and reduce switches to costly second‐line ART. ART programmes should consider the first VL measurement at three months after ART initiation.
In: Journal of the International AIDS Society, Band 22, Heft 10
ISSN: 1758-2652
AbstractIntroductionThe World Health Organization recommends the Treat‐All policy of immediate antiretroviral therapy (ART) initiation, but questions persist about its feasibility in resource‐poor settings. We assessed the feasibility of Treat‐All compared with standard of care (SOC) under routine conditions.MethodsThis prospective cohort study from southern Eswatini followed adults from HIV care enrolment to ART initiation. Between October 2014 and March 2016, Treat‐All was offered in one health zone and SOC according to the CD4 350 and 500 cells/mm3 treatment eligibility thresholds in the neighbouring health zone, each of which comprised one secondary and eight primary care facilities. We used Kaplan–Meier estimates, multivariate flexible parametric survival models and standardized survival curves to compare ART initiation between the two interventions.ResultsOf the 1726 (57.3%) patients enrolled under Treat‐All and 1287 (42.7%) under SOC, cumulative three‐month ART initiation was higher under Treat‐All (91%) than SOC (74%; p < 0.001) with a median time to ART of 1 (IQR 0 to 14) and 10 (IQR 2 to 117) days respectively. Under Treat‐All, ART initiation was higher in pregnant women (vs. non‐pregnant women: adjusted hazard ratio (aHR) 1.96, 95% confidence interval (CI) 1.70 to 2.26), those with secondary education (vs. no formal education: aHR 1.48, 95% CI 1.12 to 1.95), and patients with an HIV‐positive diagnosis before care enrolment (aHR 1.22, 95% CI 1.10 to 1.36). ART initiation was lower in patients attending secondary care facilities (aHR 0.64, 95% CI 0.58 to 0.72) and for CD4 351 to 500 when compared with CD4 201 to 350 cells/mm3 (aHR 0.84, 95% CI 0.72 to 1.00). ART initiation varied over time for TB cases, with lower hazard during the first two weeks after HIV care enrolment and higher hazards thereafter. Of patients with advanced HIV disease (n = 1085; 36.0%), crude 3‐month ART initiation was similar in both interventions (91% to 92%) although Treat‐All initiated patients more quickly during the first month after HIV care enrolment.ConclusionsART initiation was high under Treat‐All and without evidence of de‐prioritization of patients with advanced HIV disease. Additional studies are needed to understand the long‐term impact of Treat‐All on patient outcomes.
In: Journal of the International AIDS Society, Band 23, Heft 3
ISSN: 1758-2652
AbstractIntroductionThe Treat‐All policy – antiretroviral therapy (ART) initiation irrespective of CD4 cell criteria – increases access to treatment. Many ART programmes, however, reported increasing attrition and viral failure during treatment expansion, questioning the programmatic feasibility of Treat‐All in resource‐limited settings. We aimed to describe and compare programmatic outcomes between Treat‐All and standard of care (SOC) in the public sectors of Eswatini.MethodsThis is a prospective cohort study of ≥16‐year‐old HIV‐positive patients initiated on first‐line ART under Treat‐All and SOC in 18 health facilities of the Shiselweni region, from October 2014 to March 2016. SOC followed the CD4 350 and 500 cells/mm3 treatment eligibility thresholds. Kaplan‐Meier estimates were used to describe crude programmatic outcomes. Multivariate flexible parametric survival models were built to assess associations of time from ART initiation with the composite unfavourable outcome of all‐cause attrition and viral failure.ResultsOf the 3170 patients, 1888 (59.6%) initiated ART under Treat‐All at a median CD4 cell count of 329 (IQR 168 to 488) cells/mm3 compared with 292 (IQR 161 to 430) (p < 0.001) under SOC. Although crude programme retention at 36 months tended to be lower under Treat‐All (71%) than SOC (75%) (p = 0.002), it was similar in covariate‐adjusted analysis (adjusted hazard ratio [aHR] 1.06, 95% CI 0.91 to 1.23). The hazard of viral suppression was higher for Treat‐All (aHR 1.12, 95% CI 1.01 to 1.23), while the hazard of viral failure was comparable (Treat‐All: aHR 0.89, 95% CI 0.53 to 1.49). Among patients with advanced HIV disease (n = 1080), those under Treat‐All (aHR 1.13, 95% CI 0.88 to 1.44) had a similar risk of an composite unfavourable outcome to SOC. Factors increasing the risk of the composite unfavourable outcome under both interventions were aged 16 to 24 years, being unmarried, anaemia, ART initiation on the same day as HIV care enrolment and CD4 ≤ 100 cells/mm3. Under Treat‐All only, the risk of the unfavourable outcome was higher for pregnant women, WHO III/IV clinical stage and elevated creatinine.ConclusionsCompared to SOC, Treat‐All resulted in comparable retention, improved viral suppression and comparable composite outcomes of retention without viral failure.
In: Journal of the International AIDS Society, Band 25, Heft 1
ISSN: 1758-2652
AbstractIntroductionOlder adolescents aged 15–19 years continue to have high rates of loss to follow up (LTFU), and high rates of virologic non‐suppression (VNS) compared to younger adolescents and adults. Adolescent females are at risk of pregnancy, which puts those living with HIV at a dual vulnerability. Our study assessed the factors associated with VNS and LTFU in older adolescents (including pregnant females) who initiated antiretroviral therapy (ART) in South Africa.MethodsWe included adolescents aged 15–19 years initiating ART between 2004 and 2019, with ≥ one viral load (VL) measurement between 4 and 24.5 months, and ≥ 6 months follow‐up, from six South African cohorts of the International epidemiology Databases to Evaluate AIDS‐Southern Africa (IeDEA‐SA). We defined VNS as VL ≥400 copies/ml and LTFU as not being in care for ≥180 days from ART start and not known as transferred out of the clinic or dead in the first 24 months on ART. We examined factors associated with VNS and LTFU using Fine&Gray competing risk models.ResultsWe included a total of 2733 adolescents, 415 (15.2%) males, median (IQR) age at ART start of 18.6 (17.3, 19.4) years. Among females, 585/2318 (25.2%) were pregnant. Over the 24‐month follow‐up, 424 (15.5%) of all adolescents experienced VNS: range (11.1% pregnant females and 20.5% males). Over half of all adolescents were LTFU before any other event could occur. The hazard of VNS reduced with increasing age and CD4 count above 200 cells/μl at ART initiation among all adolescents having adjusted for all measured patient characteristics [adjusted sub‐distribution hazard ratio (aSHR) 19 vs. 15 years: 0.50 (95% CI: 0.36, 0.68), aSHR: >500 vs. ≤200 cells/μl: 0.22 (95% CI: 0.16, 0.31)]. The effect of CD4 count persisted in pregnant females. Increasing age and CD4 count >200 cells/μl were risk factors for LTFU among all adolescents.ConclusionsOlder adolescents had a high risk of LTFU shortly after ART start and a low risk of VNS, especially those initiating treatment during pregnancy. Interventions addressing adherence and retention should be incorporated into adolescent‐friendly services to prevent VNS and LTFU and endeavour to trace lost adolescents as soon as they are identified.
In: Journal of the International AIDS Society, Band 20, Heft 1
ISSN: 1758-2652
AbstractIntroduction: South Africa has the largest number of individuals living with HIV and the largest antiretroviral therapy (ART) programme worldwide. In September 2016, ART eligibility was extended to all 7.1 million HIV‐positive South Africans. To ensure that further expansion of services does not compromise quality of care, long‐term outcomes must be monitored. Few studies have reported long‐term mortality in resource‐constrained settings, where mortality ascertainment is challenging. Combining site records with data linked to the national vital registration system, sites in the International Epidemiology Databases to Evaluate AIDS Southern Africa collaboration can identify >95% of deaths in patients with civil identification numbers (IDs). This study used linked data to explore long‐term mortality and viral suppression among adults starting ART in South Africa.Methods: The study was a cohort analysis of routine data on adults with IDs starting ART 2004–2015 in five large ART cohorts. Mortality was estimated overall and by gender using the Kaplan‐Meier estimator and Cox's proportional hazards regression. Standardized mortality ratios (SMRs) were calculated by dividing observed numbers of deaths by numbers expected if patients had been HIV‐negative. Viral suppression in patients with viral loads (VLs) in their last year of follow‐up was the secondary outcome.Results: Among 72,812 adults followed for 350,376 person years (pyrs), the crude mortality rate was 3.08 (95% CI 3.02–3.14)/100 pyrs. Patients were predominantly female (67%) and the percentage of men initiating ART did not increase. Cumulative mortality 12 years after ART initiation was 23.9% (33.4% male and 19.4% female). Mortality peaked in patients enrolling in 2007–2009 and was higher in men than women at all durations. Observed mortality rates were higher than HIV‐negative mortality, decreasing with duration. By 48 months, observed mortality was close to that in the HIV‐negative population, and SMRs were similar for all baseline CD4 strata. Three‐quarters of patients had VLs in their last year, and 86% of these were virally suppressed.Conclusions: The South African ART programme has shown a remarkable ability to initiate and manage patients successfully over 12 years, despite rapid expansion. With further scale‐up, testing and initiating men on ART must be a national priority.
In: Journal of the International AIDS Society, Band 22, Heft 11
ISSN: 1758-2652
AbstractIntroductionStunting is a key issue for adolescents with perinatally acquired HIV (APH) that needs to be better understood. As part of the IeDEA multiregional consortium, we described growth evolution during adolescence for APH on antiretroviral therapy (ART).MethodsWe included data from sub‐Saharan Africa, the Asia‐Pacific, and the Caribbean, Central and South America regions collected between 2003 and 2016. Adolescents on ART, reporting perinatally acquired infection or entering HIV care before 10 years of age, with at least one height measurement between 10 and 16 years of age, and followed in care until at least 14 years of age were included. Characteristics at ART initiation and at 10 years of age were compared by sex. Correlates of growth defined by height‐for‐age z‐scores (HAZ) between ages 10 and 19 years were studied separately for males and females, using linear mixed models.ResultsOverall, 8737 APH were included, with 46% from Southern Africa. Median age at ART initiation was 8.1 years (interquartile range (IQR) 6.1 to 9.6), 50% were females, and 41% were stunted (HAZ<−2 SD) at ART initiation. Males and females did not differ by age and stunting at ART initiation, CD4 count over time or retention in care. At 10 years of age, 34% of males were stunted versus 39% of females (p < 0.001). Females had better subsequent growth, resulting in a higher prevalence of stunting for males compared to females by age 15 (48% vs. 25%) and 18 years (31% vs. 15%). In linear mixed models, older age at ART initiation and low CD4 count were associated with poor growth over time (p < 0.001). Those stunted at 10 years of age or at ART initiation had the greatest growth improvement during adolescence.ConclusionsPrevalence of stunting is high among APH worldwide. Substantial sex‐based differences in growth evolution during adolescence were observed in this global cohort, which were not explained by differences in age of access to HIV care, degree of immunosuppression or region. Other factors influencing growth differences in APH, such as differences in pubertal development, should be better documented, to guide further research and inform interventions to optimize growth and health outcomes among APH.
In: Journal of the International AIDS Society, Band 18, Heft 1
ISSN: 1758-2652
IntroductionThere is uncertainty regarding the completeness of death recording by civil registration and by health centres in South Africa. This paper aims to compare death recording by the two systems, in cohorts of South African patients receiving antiretroviral treatment (ART).MethodsCompleteness of death recording was estimated using a capture–recapture approach. Six ART programmes linked their patient record systems to the vital registration system using civil identity document (ID) numbers and provided data comparing the outcomes recorded in patient files and in the vital registration. Patients were excluded if they had missing/invalid IDs or had transferred to other ART programmes.ResultsAfter exclusions, 91,548 patient records were included. Of deaths recorded in patients files after 2003, 94.0% (95% CI: 93.3–94.6%) were recorded by civil registration, with completeness being significantly higher in urban areas, older adults and females. Of deaths recorded by civil registration after 2003, only 35.0% (95% CI: 34.2–35.8%) were recorded in patient files, with this proportion dropping from 60% in 2004–2005 to 30% in 2010 and subsequent years. Recording of deaths in patient files was significantly higher in children and in locations within 50 km of the health centre. When the information from the two systems was combined, an estimated 96.2% of all deaths were recorded (93.5% in children and 96.2% in adults).ConclusionsSouth Africa's civil registration system has achieved a high level of completeness in the recording of mortality. However, the fraction of deaths recorded by health centres is low and information from patient records is insufficient by itself to evaluate levels and predictors of ART patient mortality. Previously documented improvements in ART mortality over time may be biased if based only on data from patient records.
BACKGROUND: High early mortality in patients with HIV-1 starting antiretroviral therapy (ART) in sub-Saharan Africa, compared to Europe and North America, is well documented. Longer-term comparisons between settings have been limited by poor ascertainment of mortality in high burden African settings. This study aimed to compare mortality up to four years on ART between South Africa, Europe, and North America. METHODS AND FINDINGS: Data from four South African cohorts in which patients lost to follow-up (LTF) could be linked to the national population register to determine vital status were combined with data from Europe and North America. Cumulative mortality, crude and adjusted (for characteristics at ART initiation) mortality rate ratios (relative to South Africa), and predicted mortality rates were described by region at 0-3, 3-6, 6-12, 12-24, and 24-48 months on ART for the period 2001-2010. Of the adults included (30,467 [South Africa], 29,727 [Europe], and 7,160 [North America]), 20,306 (67%), 9,961 (34%), and 824 (12%) were women. Patients began treatment with markedly more advanced disease in South Africa (median CD4 count 102, 213, and 172 cells/µl in South Africa, Europe, and North America, respectively). High early mortality after starting ART in South Africa occurred mainly in patients starting ART with CD4 count <50 cells/µl. Cumulative mortality at 4 years was 16.6%, 4.7%, and 15.3% in South Africa, Europe, and North America, respectively. Mortality was initially much lower in Europe and North America than South Africa, but the differences were reduced or reversed (North America) at longer durations on ART (adjusted rate ratios 0.46, 95% CI 0.37-0.58, and 1.62, 95% CI 1.27-2.05 between 24 and 48 months on ART comparing Europe and North America to South Africa). While bias due to under-ascertainment of mortality was minimised through death registry linkage, residual bias could still be present due to differing approaches to and frequency of linkage. CONCLUSIONS: After accounting for under-ascertainment of mortality, with increasing duration on ART, the mortality rate on HIV treatment in South Africa declines to levels comparable to or below those described in participating North American cohorts, while substantially narrowing the differential with the European cohorts. Please see later in the article for the Editors' Summary. ; Funding of the International epidemiological Databases to Evaluate AIDS, Southern Africa (IeDEA-SA) collaboration was provided by the US National Institute of Allergy and Infectious Diseases (NIAID), grant no. 5U01AI069924-05. The ART Cohort Collaboration is funded by UK Medical Research Council grants and the Department for International Development (DFID), grants G0700820 and MR/J002380/1. Sources of funding of individual cohorts include the Agence Nationale de Recherche sur le SIDA et les hépatites virales (ANRS); the Institut National de la Santé et de la Recherche Médicale (INSERM); the French, Italian, and Spanish Ministries of Health; the Swiss National Science Foundation (grant 33CS30_134277); the Ministry of Science and Innovation and the Spanish Network for AIDS Research (RIS; ISCIII-RETIC RD06/006); the Stichting HIV Monitoring; the European Commission (EuroCoord grant 260694); the British Columbia and Alberta Governments; the National Institutes of Health (NIH): UW Center for AIDS Research (CFAR) (NIH grant P30 AI027757), UAB CFAR (NIH grant P30-AI027767), The Vanderbilt-Meharry CFAR (NIH grant P30 AI54999), National Institute on Alcohol Abuse and Alcoholism (U10-AA13566, U24-AA020794); the US Department of Veterans Affairs; the Michael Smith Foundation for Health Research; the Canadian Institutes of Health Research; the VHA Office of Research and Development; and unrestricted grants from Abbott, Gilead, Tibotec-Upjohn, ViiV Healthcare, MSD, GlaxoSmithKline, Pfizer, Bristol Myers Squibb, Roche, and Boehringer-Ingelheim. No funding bodies had any role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. ; Sí
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