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Featured researches published by Gilles Wandeler.


AIDS | 2014

Retention in care under universal antiretroviral therapy for HIV-infected pregnant and breastfeeding women ('Option B+') in Malawi

Lyson Tenthani; Andreas D Haas; Hannock Tweya; Andreas Jahn; Joep J. van Oosterhout; Frank Chimbwandira; Zengani Chirwa; Wingston Ng’ambi; Alan Bakali; Sam Phiri; Landon Myer; Fabio Valeri; Marcel Zwahlen; Gilles Wandeler; Olivia Keiser

Objective:To explore the levels and determinants of loss to follow-up (LTF) under universal lifelong antiretroviral therapy (ART) for pregnant and breastfeeding women (‘Option B+’) in Malawi. Design, setting, and participants:We examined retention in care, from the date of ART initiation up to 6 months, for women in the Option B+ program. We analysed nationwide facility-level data on women who started ART at 540 facilities (n = 21 939), as well as individual-level data on patients who started ART at 19 large facilities (n = 11 534). Results:Of the women who started ART under Option B+ (n = 21 939), 17% appeared to be lost to follow-up 6 months after ART initiation. Most losses occurred in the first 3 months of therapy. Option B+ patients who started therapy during pregnancy were five times more likely than women who started ART in WHO stage 3/4 or with a CD4+ cell count 350 cells/&mgr;l or less, to never return after their initial clinic visit [odds ratio (OR) 5.0, 95% confidence interval (CI) 4.2–6.1]. Option B+ patients who started therapy while breastfeeding were twice as likely to miss their first follow-up visit (OR 2.2, 95% CI 1.8–2.8). LTF was highest in pregnant Option B+ patients who began ART at large clinics on the day they were diagnosed with HIV. LTF varied considerably between facilities, ranging from 0 to 58%. Conclusion:Decreasing LTF will improve the effectiveness of the Option B+ approach. Tailored interventions, like community or family-based models of care could improve its effectiveness.


Clinical Infectious Diseases | 2012

Hepatitis C Virus Infections in the Swiss HIV Cohort Study: A Rapidly Evolving Epidemic

Gilles Wandeler; Thomas Gsponer; Andrea Bregenzer; Huldrych F. Günthard; Olivier Clerc; Alexandra Calmy; Marcel Stöckle; Enos Bernasconi; Hansjakob Furrer; Andri Rauch

BACKGROUND Hepatitis C virus (HCV) infection has a growing impact on morbidity and mortality in patients infected with human immunodeficiency virus (HIV). We assessed trends in HCV incidence in the different HIV transmission groups in the Swiss HIV Cohort Study (SHCS). METHODS HCV infection incidence was assessed from 1998, when routine serial HCV screening was introduced in the SHCS, until 2011. All HCV-seronegative patients with at least 1 follow-up serology were included. Incidence rates (IRs) of HCV infections were compared between men who have sex with men (MSM), injection drug users (IDU), and heterosexuals (HET). RESULTS HCV incidence was assessed in 3333 MSM, 123 IDU, and 3078 HET with a negative HCV serology at baseline. Over 23 707 person-years (py) for MSM, 733 py for IDU, and 20 752 py for HET, 101 (3%), 41 (33%), and 25 (1%) of patients seroconverted, respectively. The IR of HCV infections in MSM increased from 0.23 (95% credible interval [CrI], .08-.54) per 100 py in 1998 to 4.09 (95% CrI, 2.57-6.18) in 2011. The IR decreased in IDU and remained <1 per 100 py in HET. In MSM, history of inconsistent condom use (adjusted hazard ratio [HR], 2.09; 95% CI, 1.33-3.29) and past syphilis (adjusted HR, 2.11; 95% confidence interval [CI], 1.39-3.20) predicted HCV seroconversion. CONCLUSIONS In the SHCS, HCV infection incidence decreased in IDU, remained stable in HET, and increased 18-fold in MSM in the last 13 years. These observations underscore the need for improved HCV surveillance and prevention among HIV-infected MSM.


Tropical Medicine & International Health | 2012

Loss to programme between HIV diagnosis and initiation of antiretroviral therapy in sub-Saharan Africa: systematic review and meta-analysis

Catrina Mugglin; Janne Estill; Gilles Wandeler; Nicole Bender; Matthias Egger; Thomas Gsponer; Olivia Keiser

Objectives  To assess the proportion of patients lost to programme (died, lost to follow‐up, transferred out) between HIV diagnosis and start of antiretroviral therapy (ART) in sub‐Saharan Africa, and determine factors associated with loss to programme.


AIDS | 2012

Missed opportunities to prevent mother-to-child-transmission: systematic review and meta-analysis

Celina Wettstein; Catrina Mugglin; Matthias Egger; Nello Blaser; Luisa Salazar Vizcaya; Janne Estill; Nicole Bender; Mary-Ann Davies; Gilles Wandeler; Olivia Keiser

Objectives:To determine magnitude and reasons of loss to program and poor antiretroviral prophylaxis coverage in prevention of mother-to-child transmission (PMTCT) programs in sub-Saharan Africa. Design:Systematic review and meta-analysis. Methods:We searched PubMed and Embase databases for PMTCT studies in sub-Saharan Africa published between January 2002 and March 2012. Outcomes were the percentage of pregnant women tested for HIV, initiating antiretroviral prophylaxis, having a CD4 cell count measured, and initiating antiretroviral combination therapy (cART) if eligible. In children outcomes were early infant diagnosis for HIV, and cART initiation. We combined data using random-effects meta-analysis and identified predictors of uptake of interventions. Results:Forty-four studies from 15 countries including 75 172 HIV-infected pregnant women were analyzed. HIV-testing uptake at antenatal care services was 94% [95% confidence intervals (CIs) 92–95%] for opt-out and 58% (95% CI 40–75%) for opt-in testing. Coverage with any antiretroviral prophylaxis was 70% (95% CI 64–76%) and 62% (95% CI 50–73%) of pregnant women eligible for cART received treatment. Sixty-four percent (95% CI 48–81%) of HIV exposed infants had early diagnosis performed and 55% (95% CI 36–74%) were tested between 12 and 18 months. Uptake of PMTCT interventions was improved if cART was provided at the antenatal clinic and if the male partner was involved. Conclusion:In sub-Saharan Africa, uptake of PMTCT interventions and early infant diagnosis is unsatisfactory. An integrated family-centered approach seems to improve retention.


Journal of Acquired Immune Deficiency Syndromes | 2013

Immunodeficiency at the start of combination antiretroviral therapy in low-, middle- and high-income countries

Dorita Avila; Keri N. Althoff; Catrina Mugglin; Kara Wools-Kaloustian; Manuel Koller; François Dabis; Denis Nash; Thomas Gsponer; Somnuek Sungkanuparph; Catherine C. McGowan; Margaret T May; David A. Cooper; Cleophas Chimbetete; Marcelo Wolff; Ann C. Collier; Hamish McManus; Mary-Ann Davies; Dominique Costagliola; Crabtree-Ramirez B; Romanee Chaiwarith; Angela Cescon; Morna Cornell; Lameck Diero; Praphan Phanuphak; Adrien Sawadogo; Jochen Ehmer; Serge P Eholie; Patrick Ck Li; Matthew P. Fox; Neel R. Gandhi

Objective:To describe the CD4 cell count at the start of combination antiretroviral therapy (cART) in low-income (LIC), lower middle-income (LMIC), upper middle-income (UMIC), and high-income (HIC) countries. Methods:Patients aged 16 years or older starting cART in a clinic participating in a multicohort collaboration spanning 6 continents (International epidemiological Databases to Evaluate AIDS and ART Cohort Collaboration) were eligible. Multilevel linear regression models were adjusted for age, gender, and calendar year; missing CD4 counts were imputed. Results:In total, 379,865 patients from 9 LIC, 4 LMIC, 4 UMIC, and 6 HIC were included. In LIC, the median CD4 cell count at cART initiation increased by 83% from 80 to 145 cells/&mgr;L between 2002 and 2009. Corresponding increases in LMIC, UMIC, and HIC were from 87 to 155 cells/&mgr;L (76% increase), 88 to 135 cells/&mgr;L (53%), and 209 to 274 cells/&mgr;L (31%). In 2009, compared with LIC, median counts were 13 cells/&mgr;L [95% confidence interval (CI): −56 to +30] lower in LMIC, 22 cells/&mgr;L (−62 to +18) lower in UMIC, and 112 cells/&mgr;L (+75 to +149) higher in HIC. They were 23 cells/&mgr;L (95% CI: +18 to +28 cells/&mgr;L) higher in women than men. Median counts were 88 cells/&mgr;L (95% CI: +35 to +141 cells/&mgr;L) higher in countries with an estimated national cART coverage >80%, compared with countries with <40% coverage. Conclusions:Median CD4 cell counts at the start of cART increased 2000–2009 but remained below 200 cells/&mgr;L in LIC and MIC and below 300 cells/&mgr;L in HIC. Earlier start of cART will require substantial efforts and resources globally.


American Journal of Epidemiology | 2013

Risk Factors for Anal Cancer in Persons Infected With HIV: A Nested Case-Control Study in the Swiss HIV Cohort Study

Barbara Bertisch; Silvia Franceschi; Mauro Lise; Pietro Vernazza; Olivia Keiser; Franziska Schöni-Affolter; Christine Bouchardy; Silvia Dehler; Fabio Levi; Gernot Jundt; Silvia Ess; Michael Pawlita; Helen Kovari; Gilles Wandeler; Alexandra Calmy; Matthias Cavassini; Marcel Stöckle; Gary M. Clifford

Although persons infected with human immunodeficiency virus (HIV), particularly men who have sex with men, are at excess risk for anal cancer, it has been difficult to disentangle the influences of anal exposure to human papillomavirus (HPV) infection, immunodeficiency, and combined antiretroviral therapy. A case-control study that included 59 anal cancer cases and 295 individually matched controls was nested in the Swiss HIV Cohort Study (1988-2011). In a subset of 41 cases and 114 controls, HPV antibodies were tested. A majority of anal cancer cases (73%) were men who have sex with men. Current smoking was significantly associated with anal cancer (odds ratio (OR) = 2.59, 95% confidence interval (CI): 1.25, 5.34), as were antibodies against L1 (OR = 4.52, 95% CI: 2.00, 10.20) and E6 (OR = ∞, 95% CI: 4.64, ∞) of HPV16, as well as low CD4+ cell counts, whether measured at nadir (OR per 100-cell/μL decrease = 1.53, 95% CI: 1.18, 2.00) or at cancer diagnosis (OR per 100-cell/μL decrease = 1.24, 95% CI: 1.08, 1.42). However, the influence of CD4+ cell counts appeared to be strongest 6-7 years prior to anal cancer diagnosis (OR for <200 vs. ≥500 cells/μL = 14.0, 95% CI: 3.85, 50.9). Smoking cessation and avoidance of even moderate levels of immunosuppression appear to be important in reducing long-term anal cancer risks.


Journal of Acquired Immune Deficiency Syndromes | 2012

Outcomes of antiretroviral treatment programs in rural Southern Africa

Gilles Wandeler; Olivia Keiser; Karolin Pfeiffer; Sabrina Pestilli; Christiane Fritz; Niklaus Daniel Labhardt; Franzisco Mbofana; Robert Mudyiradima; Jan Emmel; Matthias Egger; Jochen Ehmer

Background:Data on outcomes of antiretroviral treatment (ART) programs in rural sub-Saharan African are scarce. We describe early losses and long-term outcomes in 6 rural programs in Southern Africa with limited access to viral load monitoring and second-line ART. Methods:Patients aged ≥16 years starting ART in 2 programs each in Zimbabwe, Mozambique, and Lesotho were included. We evaluated risk factors for no follow-up after starting ART and mortality and loss to follow-up (LTFU) over 3 years of ART, using logistic regression and competing risk models. Odds ratios and subdistribution hazard ratios, adjusted for gender, age category, CD4 category, and World Health Organization stage at start of ART are reported. Results:Among 7725 patients, 449 (5.8%) did not return after initiation of ART. During 9575 person-years, 698 (9.6%) of those with at least 1 follow-up visit died, and 1319 (18.1%) were LTFU. At 3 years, the cumulative incidence of death and LTFU were 12.5% (11.5%–13.5%) and 25.4% (24.0%–26.9%), respectively, with important differences between countries as follows: in Zimbabwe 75.1% (72.8%–77.3%) were alive and on ART at 3 years compared with 55.4% (52.8%–58.0%) in Lesotho and 51.6% (48.0%–55.2%) in Mozambique. In all settings, young age and male gender predicted LTFU, whereas advanced clinical stage and low baseline CD4 counts predicted death. Conclusions:In African ART programs with limited access to second-line treatment, mortality, and LTFU are high in the first 3 years of ART. Low retention in care is a major threat to the sustainability of ART delivery in Southern Africa, particularly in rural sites.


Neurology | 2014

Antiretroviral penetration into the CNS and incidence of AIDS-defining neurologic conditions

Ellen C. Caniglia; Lauren E. Cain; Amy C. Justice; Janet P. Tate; Roger Logan; Caroline Sabin; Alan Winston; Ard van Sighem; José M. Miró; Daniel Podzamczer; Ashley Olson; José Ramón Arribas; Santiago Moreno; Laurence Meyer; Jorge del Romero; François Dabis; Heiner C. Bucher; Gilles Wandeler; Georgia Vourli; Athanasios Skoutelis; Emilie Lanoy; Jacques Gasnault; Dominique Costagliola; Miguel A. Hernán

Objective: The link between CNS penetration of antiretrovirals and AIDS-defining neurologic disorders remains largely unknown. Methods: HIV-infected, antiretroviral therapy–naive individuals in the HIV-CAUSAL Collaboration who started an antiretroviral regimen were classified according to the CNS Penetration Effectiveness (CPE) score of their initial regimen into low (<8), medium (8–9), or high (>9) CPE score. We estimated “intention-to-treat” hazard ratios of 4 neuroAIDS conditions for baseline regimens with high and medium CPE scores compared with regimens with a low score. We used inverse probability weighting to adjust for potential bias due to infrequent follow-up. Results: A total of 61,938 individuals were followed for a median (interquartile range) of 37 (18, 70) months. During follow-up, there were 235 cases of HIV dementia, 169 cases of toxoplasmosis, 128 cases of cryptococcal meningitis, and 141 cases of progressive multifocal leukoencephalopathy. The hazard ratio (95% confidence interval) for initiating a combined antiretroviral therapy regimen with a high vs low CPE score was 1.74 (1.15, 2.65) for HIV dementia, 0.90 (0.50, 1.62) for toxoplasmosis, 1.13 (0.61, 2.11) for cryptococcal meningitis, and 1.32 (0.71, 2.47) for progressive multifocal leukoencephalopathy. The respective hazard ratios (95% confidence intervals) for a medium vs low CPE score were 1.01 (0.73, 1.39), 0.80 (0.56, 1.15), 1.08 (0.73, 1.62), and 1.08 (0.73, 1.58). Conclusions: We estimated that initiation of a combined antiretroviral therapy regimen with a high CPE score increases the risk of HIV dementia, but not of other neuroAIDS conditions.


British Journal of Cancer | 2012

Lung cancer in the Swiss HIV Cohort Study: role of smoking, immunodeficiency and pulmonary infection.

Gary M. Clifford; Mauro Lise; Silvia Franceschi; Matthias Egger; Christine Bouchardy; D Korol; Fabio Levi; Silvia Ess; Gernot Jundt; Gilles Wandeler; Jan Fehr; Patrick Schmid; Manuel Battegay; Enos Bernasconi; Matthias Cavassini; Alexandra Calmy; Olivia Keiser; Franziska Schöni-Affolter

Background:Immunodeficiency and AIDS-related pulmonary infections have been suggested as independent causes of lung cancer among HIV-infected persons, in addition to smoking.Methods:A total of 68 lung cancers were identified in the Swiss HIV Cohort Study (SHCS) or through linkage with Swiss Cancer Registries (1985–2010), and were individually matched to 337 controls by centre, gender, HIV-transmission category, age and calendar period. Odds ratios (ORs) were estimated by conditional logistic regression.Results:Overall, 96.2% of lung cancers and 72.9% of controls were ever smokers, confirming the high prevalence of smoking and its strong association with lung cancer (OR for current vs never=14.4, 95% confidence interval (95% CI): 3.36–62.1). No significant associations were observed between CD4+ cell count and lung cancer, neither when measured within 1 year (OR for <200 vs ⩾500=1.21, 95% CI: 0.49–2.96) nor further back in time, before lung cancer diagnosis. Combined antiretroviral therapy was not significantly associated with lung cancer (OR for ever vs never=0.67, 95% CI: 0.29–1.52), and nor was a history of AIDS with (OR=0.49, 95% CI: 0.19–1.28) or without (OR=0.53, 95% CI: 0.24–1.18) pulmonary involvement.Conclusion:Lung cancer in the SHCS does not seem to be clearly associated with immunodeficiency or AIDS-related pulmonary disease, but seems to be attributable to heavy smoking.


The Lancet HIV | 2015

Monitoring and switching of first-line antiretroviral therapy in adult treatment cohorts in sub-Saharan Africa: collaborative analysis

Andreas D Haas; Olivia Keiser; Eric Balestre; Steve Brown; Emmanuel Bissagnene; Cleophas Chimbetete; François Dabis; Mary-Ann Davies; Christopher J. Hoffmann; Patrick Oyaro; Rosalind Parkes-Ratanshi; Steven J. Reynolds; Izukanji Sikazwe; Kara Wools-Kaloustian; D Marcel Zannou; Gilles Wandeler; Matthias Egger

BACKGROUND HIV-1 viral load (VL) testing is recommended to monitor antiretroviral therapy (ART) but not universally available. We examined monitoring of first-line and switching to second-line ART in sub-Saharan Africa, 2004-2013. METHODS Adult HIV-1 infected patients starting combination ART in 16 countries were included. Switching was defined as a change from a non-nucleoside reverse-transcriptase inhibitor (NNRTI)-based regimen to a protease inhibitor (PI)-based regimen, with a change of ≥1 NRTI. Virological and immunological failures were defined per World Health Organization criteria. We calculated cumulative probabilities of switching and hazard ratios with 95% confidence intervals (CI) comparing routine VL monitoring, targeted VL monitoring, CD4 cell monitoring and clinical monitoring, adjusted for programme and individual characteristics. FINDINGS Of 297,825 eligible patients, 10,352 patients (3·5%) switched during 782,412 person-years of follow-up. Compared to CD4 monitoring hazard ratios for switching were 3·15 (95% CI 2·92-3·40) for routine VL, 1·21 (1·13-1·30) for targeted VL and 0·49 (0·43-0·56) for clinical monitoring. Overall 58.0% of patients with confirmed virological and 19·3% of patients with confirmed immunological failure switched within 2 years. Among patients who switched the percentage with evidence of treatment failure based on a single CD4 or VL measurement ranged from 32·1% with clinical to 84.3% with targeted VL monitoring. Median CD4 counts at switching were 215 cells/µl under routine VL monitoring but lower with other monitoring (114-133 cells/µl). INTERPRETATION Overall few patients switched to second-line ART and switching occurred late in the absence of routine viral load monitoring. Switching was more common and occurred earlier with targeted or routine viral load testing.BACKGROUND HIV-1 viral load testing is recommended to monitor antiretroviral therapy (ART) but is not universally available. The aim of our study was to assess monitoring of first-line ART and switching to second-line ART in sub-Saharan Africa. METHODS We did a collaborative analysis of cohort studies from 16 countries in east Africa, southern Africa, and west Africa that participate in the international epidemiological database to evaluate AIDS (IeDEA). We included adults infected with HIV-1 who started combination ART between January, 2004, and January, 2013. We defined switching of ART as a change from a non-nucleoside reverse-transcriptase inhibitor (NNRTI)-based regimen to one including a protease inhibitor, with adjustment of one or more nucleoside reverse-transcriptase inhibitors (NRTIs). Virological and immunological failures were defined according to WHO criteria. We calculated cumulative probabilities of switching and hazard ratios with 95% CIs comparing routine viral load monitoring, targeted viral load monitoring, CD4 monitoring, and clinical monitoring, adjusting for programme and individual characteristics. FINDINGS Of 297,825 eligible patients, 10,352 (3%) switched to second-line ART during 782 ,412 person-years of follow-up. Compared with CD4 monitoring, hazard ratios for switching were 3·15 (95% CI 2·92-3·40) for routine viral load monitoring, 1·21 (1·13-1·30) for targeted viral load monitoring, and 0·49 (0·43-0·56) for clinical monitoring. Of 6450 patients with confirmed virological failure, 58·0% (95% CI 56·5-59·6) switched by 2 years, and of 15,892 patients with confirmed immunological failure, 19·3% (18·5-20·0) switched by 2 years. Of 10,352 patients who switched, evidence of treatment failure based on one CD4 count or viral load measurement ranged from 86 (32%) of 268 patients with clinical monitoring to 3754 (84%) of 4452 with targeted viral load monitoring. Median CD4 counts at switching were 215 cells per μL (IQR 117-335) with routine viral load monitoring, but were lower with other types of monitoring (range 114-133 cells per μL). INTERPRETATION Overall, few patients switched to second-line ART and switching happened late in the absence of routine viral load monitoring. Switching was more common and happened earlier after initiation of ART with targeted or routine viral load testing. FUNDING National Institute of Allergy and Infectious Diseases, Swiss National Science Foundation.

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Michael J. Vinikoor

University of Alabama at Birmingham

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Jan Fehr

University of Zurich

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