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Featured researches published by Ard van Sighem.


Annals of Epidemiology | 2009

Reemergence of the HIV epidemic among men who have sex with men in North America, Western Europe, and Australia, 1996-2005.

Patrick S. Sullivan; Osamah Hamouda; Valerie Delpech; Jennifer Geduld; Joseph Prejean; Caroline Semaille; John M. Kaldor; Cinta Folch; Eline Op de Coul; Ulrich Marcus; Gwenda Hughes; Chris P. Archibald; Françoise Cazein; Ann McDonald; Jordi Casabona; Ard van Sighem; Kevin A. Fenton

PURPOSE To describe and contextualize changes in rates of human immunodeficiency virus (HIV) notifications in men who have sex with men (MSM) in eight countries (Australia, Canada, France, Germany, Netherlands, Spain, United Kingdom, and United States) from 1996-2005. METHODS We analyzed trends in HIV notification rates from 1996-2000 and 2000-2005 by generalized linear regression and estimated annual percentage change (EAPC) in rates of HIV notifications. To interpret trends, we visually examined graphs of primary and secondary syphilis reports among MSM and the prevalence of recent HIV testing. RESULTS The rate of HIV notifications among MSM declined 5.2% per year (95% confidence interval [CI]: -5.8%, -4.7%) from 1996-2000, and increased 3.3% per year (95% CI: +2.9%,+3.7%) from 2000-2005. During the period of increasing HIV diagnoses, increases in primary and secondary syphilis diagnoses occurred among MSM, but recent HIV testing among MSM did not seem to increase. CONCLUSIONS After declining in the second half of the 1990s, HIV notification rates for MSM increased beginning in 2000. Increased HIV notifications in MSM are not wholly explained by changes in HIV testing. Urgent efforts are required to develop effective HIV prevention interventions for MSM, and implement them broadly in these countries.


AIDS | 2010

Life expectancy of recently diagnosed asymptomatic HIV-infected patients approaches that of uninfected individuals

Ard van Sighem; Luuk Gras; Peter Reiss; Kees Brinkman; Frank de Wolf

Objective:To compare life expectancies between recently diagnosed HIV-infected patients and age and sex-matched uninfected individuals from the general population. Design:National observational HIV cohort in the Netherlands. Methods:Four thousand, six hundred and twelve patients diagnosed with HIV between 1998 and 2007 and still antiretroviral therapy-naive as of 24 weeks after diagnosis were selected. Progression to death compared to the age and sex-matched general population was studied with a multivariate hazards model in 4174 (90.5%) patients without AIDS events at 24 weeks. Life expectancy and number of life years lost were calculated using the predicted survival distribution. Results:During 17 580 person-years of follow-up since 24 weeks after diagnosis [median follow-up 3.3 years, interquartile range (IQR) 1.6–5.8], 118 deaths occurred, yielding a mortality rate of 6.7 [95% confidence interval (CI) 5.5–8.0] per 1000 person-years. Median CD4 cell counts at 24 weeks were 480 cells/μl (IQR 360–650). According to the model, the median number of years lived from age 25 was 52.7 (IQR 44.2–59.3; general population 53.1) for men and 57.8 (49.2–63.7; 58.1) for women without CDC-B event. The number of life years lost varied between 0.4 if diagnosed with HIV at age 25 and 1.4 if diagnosed at age 55; for patients with a CDC-B event this range was 1.8–8.0 years. Conclusion:The life expectancy of asymptomatic HIV-infected patients who are still treatment-naive and have not experienced a CDC-B or C event at 24 weeks after diagnosis approaches that of non-infected individuals. However, follow-up time is short compared to the expected number of years lived.


Lancet Infectious Diseases | 2011

Effect of transmitted drug resistance on virological and immunological response to initial combination antiretroviral therapy for HIV (EuroCoord-CHAIN joint project): a European multicohort study

Linda Wittkop; Huldrych F. Günthard; Frank de Wolf; David Dunn; Alessandro Cozzi-Lepri; Andrea De Luca; Claudia Kücherer; Niels Obel; Viktor von Wyl; Bernard Masquelier; Christoph Stephan; Carlo Torti; Andrea Antinori; Federico García; Ali Judd; Kholoud Porter; Rodolphe Thiébaut; Hannah Castro; Ard van Sighem; Céline Colin; Jesper Kjaer; Jens D. Lundgren; Roger Paredes; Anton Pozniak; Bonaventura Clotet; Andrew N. Phillips; Deenan Pillay; Geneviève Chêne

BACKGROUND The effect of transmitted drug resistance (TDR) on first-line combination antiretroviral therapy (cART) for HIV-1 needs further study to inform choice of optimum drug regimens. We investigated the effect of TDR on outcome in the first year of cART within a large European collaboration. METHODS HIV-infected patients of any age were included if they started cART (at least three antiretroviral drugs) for the first time after Jan 1, 1998, and were antiretroviral naive and had at least one sample for a genotypic test taken before the start of cART. We used the WHO drug resistance list and the Stanford algorithm to classify patients into three resistance categories: no TDR, at least one mutation and fully-active cART, or at least one mutation and resistant to at least one prescribed drug. Virological failure was defined as time to the first of two consecutive viral load measurements over 500 copies per mL after 6 months of therapy. FINDINGS Of 10,056 patients from 25 cohorts, 9102 (90·5%) had HIV without TDR, 475 (4·7%) had at least one mutation but received fully-active cART, and 479 (4·8%) had at least one mutation and resistance to at least one drug. Cumulative Kaplan-Meier estimates for virological failure at 12 months were 4·2% (95% CI 3·8-4·7) for patients in the no TDR group, 4·7% (2·9-7·5) for those in the TDR and fully-active cART group, and 15·1% (11·9-19·0) for those in the TDR and resistant group (log-rank p<0·0001). The hazard ratio for the difference in virological failure between patients with TDR and resistance to at least one drug and those without TDR was 3·13 (95% CI 2·33-4·20, p<0·0001). The hazard ratio for the difference between patients with TDR receiving fully-active cART and patients without TDR was 1·47 (95% CI 0·19-2·38, p=0·12). In stratified analysis, the hazard ratio for the risk of virological failure in patients with TDR who received fully-active cART that included a non-nucleoside reverse transcriptase inhibitor (NNRTI) compared with those without TDR was 2·0 (95% CI 0·9-4·7, p=0·093). INTERPRETATION These findings confirm present treatment guidelines for HIV, which state that the initial treatment choice should be based on resistance testing in treatment-naive patients. FUNDING European Communitys Seventh Framework Programme FP7/2007-2013 and Gilead.


International Journal of Epidemiology | 2012

All-cause mortality in treated HIV-infected adults with CD4 ≥500/mm3 compared with the general population: evidence from a large European observational cohort collaboration

Charlotte Lewden; Vincent Bouteloup; Stéphane De Wit; Caroline Sabin; Amanda Mocroft; Jan Christian Wasmuth; Ard van Sighem; Ole Kirk; Niels Obel; George Panos; Jade Ghosn; François Dabis; Murielle Mary-Krause; Catherine Leport; Santiago Pérez-Hoyos; Paz Sobrino-Vegas; Christoph Stephan; Antonella Castagna; Andrea Antinori; Antonella d'Arminio Monforte; Carlo Torti; Cristina Mussini; Virginia Isern; Alexandra Calmy; Ramon Teira; Matthias Egger; Jesper Grarup; Geneviève Chêne

BACKGROUND Using data from a large European collaborative study, we aimed to identify the circumstances in which treated HIV-infected individuals will experience similar mortality rates to those of the general population. METHODS Adults were eligible if they initiated combination anti-retroviral treatment (cART) between 1998 and 2008 and had one prior CD4 measurement within 6 months. Standardized mortality ratios (SMRs) and excess mortality rates compared with the general population were estimated using Poisson regression. Periods of follow-up were classified according to the current CD4 count. RESULTS Of the 80 642 individuals, 70% were men, 16% were injecting drug users (IDUs), the median age was 37 years, median CD4 count 225/mm(3) at cART initiation and median follow-up was 3.5 years. The overall mortality rate was 1.2/100 person-years (PY) (men: 1.3, women: 0.9), 4.2 times as high as that in the general population (SMR for men: 3.8, for women: 7.4). Among 35 316 individuals with a CD4 count ≥500/mm(3), the mortality rate was 0.37/100 PY (SMR 1.5); mortality rates were similar to those of the general population in non-IDU men [SMR 0.9, 95% confidence interval (95% CI) 0.7-1.3] and, after 3 years, in women (SMR 1.1, 95% CI 0.7-1.7). Mortality rates in IDUs remained elevated, though a trend to decrease with longer durations with high CD4 count was seen. A prior AIDS diagnosis was associated with higher mortality. CONCLUSIONS Mortality patterns in most non-IDU HIV-infected individuals with high CD4 counts on cART are similar to those in the general population. The persistent role of a prior AIDS diagnosis underlines the importance of early diagnosis of HIV infection.


Annals of Internal Medicine | 2011

When to initiate combined antiretroviral therapy to reduce mortality and AIDS-defining illness in HIV-infected persons in developed countries: an observational study.

Lauren E. Cain; Roger Logan; James M. Robins; Jonathan A C Sterne; Caroline Sabin; Loveleen Bansi; Amy C. Justice; Joseph L. Goulet; Ard van Sighem; Frank de Wolf; Heiner C. Bucher; Viktor von Wyl; Anna Esteve; Jordi Casabona; Julia del Amo; Santiago Moreno; Rémonie Seng; Laurence Meyer; Santiago Pérez-Hoyos; Roberto Muga; Sara Lodi; Emilie Lanoy; Dominique Costagliola; Miguel A. Hernán

BACKGROUND Most clinical guidelines recommend that AIDS-free, HIV-infected persons with CD4 cell counts below 0.350 × 10(9) cells/L initiate combined antiretroviral therapy (cART), but the optimal CD4 cell count at which cART should be initiated remains a matter of debate. OBJECTIVE To identify the optimal CD4 cell count at which cART should be initiated. DESIGN Prospective observational data from the HIV-CAUSAL Collaboration and dynamic marginal structural models were used to compare cART initiation strategies for CD4 thresholds between 0.200 and 0.500 × 10(9) cells/L. SETTING HIV clinics in Europe and the Veterans Health Administration system in the United States. PATIENTS 20, 971 HIV-infected, therapy-naive persons with baseline CD4 cell counts at or above 0.500 × 10(9) cells/L and no previous AIDS-defining illnesses, of whom 8392 had a CD4 cell count that decreased into the range of 0.200 to 0.499 × 10(9) cells/L and were included in the analysis. MEASUREMENTS Hazard ratios and survival proportions for all-cause mortality and a combined end point of AIDS-defining illness or death. RESULTS Compared with initiating cART at the CD4 cell count threshold of 0.500 × 10(9) cells/L, the mortality hazard ratio was 1.01 (95% CI, 0.84 to 1.22) for the 0.350 threshold and 1.20 (CI, 0.97 to 1.48) for the 0.200 threshold. The corresponding hazard ratios were 1.38 (CI, 1.23 to 1.56) and 1.90 (CI, 1.67 to 2.15), respectively, for the combined end point of AIDS-defining illness or death. LIMITATIONS CD4 cell count at cART initiation was not randomized. Residual confounding may exist. CONCLUSION Initiation of cART at a threshold CD4 count of 0.500 × 10(9) cells/L increases AIDS-free survival. However, mortality did not vary substantially with the use of CD4 thresholds between 0.300 and 0.500 × 10(9) cells/L.


AIDS | 2008

A resurgent HIV-1 epidemic among men who have sex with men in the era of potent antiretroviral therapy

Daniela Bezemer; Frank de Wolf; Maarten C. Boerlijst; Ard van Sighem; T. Déirdre Hollingsworth; Maria Prins; Ronald B. Geskus; Luuk Gras; Roel A. Coutinho; Christophe Fraser

Objective:Reducing viral load, highly active antiretroviral therapy has the potential to limit onwards transmission of HIV-1 and thus help contain epidemic spread. However, increases in risk behaviour and resurgent epidemics have been widely reported post-highly active antiretroviral therapy. The aim of this study was to quantify the impact that highly active antiretroviral therapy had on the epidemic. Design:We focus on the HIV-1 epidemic among men who have sex with men in the Netherlands, which has been well documented over the past 20 years within several long-standing national surveillance programs. Methods:We used a mathematical model including highly active antiretroviral therapy use and estimated the changes in risk behaviour and diagnosis rate needed to explain annual data on HIV and AIDS diagnoses. Results:We show that the reproduction number R(t), a measure of the state of the epidemic, declined early on from initial values above two and was maintained below one from 1985 to 2000. Since 1996, when highly active antiretroviral therapy became widely used, the risk behaviour rate has increased 66%, resulting in an increase of R(t) to 1.04 in the latest period 2000–2004 (95% confidence interval 0.98–1.09) near or just above the threshold for a self-sustaining epidemic. Hypothetical scenario analysis shows that the epidemiological benefits of highly active antiretroviral therapy and earlier diagnosis on incidence have been entirely offset by increases in the risk behaviour rate. Conclusion:We provide the first detailed quantitative analysis of the HIV epidemic in a well defined population and find a resurgent epidemic in the era of highly active antiretroviral therapy, most likely predominantly caused by increasing sexual risk behaviour.


Journal of Acquired Immune Deficiency Syndromes | 2007

CD4 cell counts of 800 cells/mm3 or greater after 7 years of highly active antiretroviral therapy are feasible in most patients starting with 350 cells/mm3 or greater

Luuk Gras; Anouk M. Kesselring; James Griffin; Ard van Sighem; Christophe Fraser; Azra C. Ghani; Frank Miedema; Peter Reiss; Joep M. A. Lange; Frank de Wolf

Objective:CD4 cell count changes in therapy-naive patients were investigated during 7 years of highly active antiretroviral therapy (HAART) in an observational cohort. Methods:Three endpoints were studied: (1) time to ≥800 CD4 cells/mm3 in 5299 therapy-naive patients starting HAART, (2) CD4 cell count changes during 7 years of uninterrupted HAART in a subset of 544 patients, and (3) reaching a plateau in CD4 cell restoration after 5 years of HAART in 366 virologically suppressed patients. Results:Among patients with <50, 50 to 200, 200 to 350, 350 to 500, and ≥500 CD4 cells/mm3 at baseline, respectively, 20%, 26%, 46%, 73%, and 87% reached ≥800 CD4 cells/mm3 within 7 years of starting HAART. Periods with HIV RNA levels >500 copies/mL and age ≥50 years were associated with lesser increases in CD4 cell counts between 6 months and 7 years. Having reached ≥800 CD4 cells/mm3 at 5 years, age ≥50 years, and ≥1 HIV RNA measurement >1000 copies/mL between 5 and 7 years were associated with a plateau in CD4 cell restoration. Conclusions:Restoration to CD4 cell counts ≥800 cells/mm3 is feasible within 7 years of HAART in most HIV-infected patients starting with ≥350 cells/mm3 and achieving sufficient suppression of viral replication. Particularly in patients ≥50 years of age, it may be beneficial to start earlier than current guidelines recommend.


Lancet Infectious Diseases | 2015

Future challenges for clinical care of an ageing population infected with HIV: a modelling study

Mikaela Smit; Kees Brinkman; Suzanne E. Geerlings; Colette Smit; Kalyani Thyagarajan; Ard van Sighem; Frank de Wolf; Timothy B. Hallett

Summary Background The population infected with HIV is getting older and these people will increasingly develop age-related non-communicable diseases (NCDs). We aimed to quantify the scale of the change and the implications for HIV care in the Netherlands in the future. Methods We constructed an individual-based model of the ageing HIV-infected population, which followed patients on HIV treatment as they age, develop NCDs—including cardiovascular disease (hypertension, hypercholesterolaemia, myocardial infarctions, and strokes), diabetes, chronic kidney disease, osteoporosis, and non-AIDS malignancies—and start co-medication for these diseases. The model was parameterised by use of data for 10 278 patients from the national Dutch ATHENA cohort between 1996 and 2010. We made projections up to 2030. Findings Our model suggests that the median age of HIV-infected patients on combination antiretroviral therapy (ART) will increase from 43·9 years in 2010 to 56·6 in 2030, with the proportion of HIV-infected patients aged 50 years or older increasing from 28% in 2010 to 73% in 2030. In 2030, we predict that 84% of HIV-infected patients will have at least one NCD, up from 29% in 2010, with 28% of HIV-infected patients in 2030 having three or more NCDs. 54% of HIV-infected patients will be prescribed co-medications in 2030, compared with 13% in 2010, with 20% taking three or more co-medications. Most of this change will be driven by increasing prevalence of cardiovascular disease and associated drugs. Because of contraindications and drug–drug interactions, in 2030, 40% of patients could have complications with the currently recommended first-line HIV regimens. Interpretation The profile of patients in the Netherlands infected with HIV is changing, with increasing numbers of older patients with multiple morbidities. These changes mean that, in the near future, HIV care will increasingly need to draw on a wide range of medical disciplines, in addition to evidence-based screening and monitoring protocols to ensure continued high-quality care. These findings are based on a large dataset of HIV-infected patients in the Netherlands, but we believe that the overall patterns will be repeated elsewhere in Europe and North America. The implications of such a trend for care of HIV-infected patients in high-burden countries in Africa could present a particular challenge. Funding Medical Research Council, Bill & Melinda Gates Foundation, Rush Foundation, and Netherlands Ministry of Health, Welfare and Sport.


AIDS | 2010

Transmission networks of HIV-1 among men having sex with men in the Netherlands

Daniela Bezemer; Ard van Sighem; Vladimir V. Lukashov; Lia van der Hoek; Nicole K. T. Back; Rob Schuurman; Charles A. Boucher; Eric C. J. Claas; Maarten C. Boerlijst; Roel A. Coutinho; Frank de Wolf

Objective: To obtain insight in the HIV-1 transmission networks among men having sex with men (MSM) in the Netherlands. Design: A phylogenetic tree was constructed from polymerase sequences isolated from 2877 HIV-1 subtype B-infected patients monitored as part of the AIDS Therapy Evaluation in the Netherlands (ATHENA) nationwide observational cohort. Methods: For MSM with a known date of infection, the most similar sequences were selected as potential transmission pairs when they clustered with bootstrap value of at least 99%. Time from infection to onward transmission was estimated as the median time between dates of infection for each transmission pair. The source of infections with a resistant strain was traced using the entire phylogenetic tree. Results: Of sequences from 403 MSM with a known date of infection between 1987 and 2007, 175 (43%) formed 63 clusters. Median time to onward transmission was 1.4 years (interquartile range 0.6–2.7). Twenty-four (6%) MSM carried a virus with resistance-related mutations, 13 of these were in eight clusters together with sequences from 28 other patients in the entire phylogenetic tree. Six clusters contained sequences obtained from 29 men all presenting the same resistance-related mutations. Conclusion: From our selection of likely transmission pairs, we conclude that onward transmission of HIV-1 from infected MSM in the Netherlands happens both during and after primary infection. Transmission of resistant strains from the antiretroviral therapy-treated population is limited, but strains with resistance-related mutations have formed subepidemics.


The Lancet HIV | 2017

Survival of HIV-positive patients starting antiretroviral therapy between 1996 and 2013: a collaborative analysis of cohort studies

Adam Trickey; Margaret T May; Jorg-Janne Vehreschild; Niels Obel; M. John Gill; Heidi M. Crane; Christoph Boesecke; Sophie Patterson; Sophie Grabar; Charles Cazanave; Matthias Cavassini; Leah Shepherd; Antonella d'Arminio Monforte; Ard van Sighem; Mike Saag; Fiona Lampe; Vicky Hernando; Marta Montero; Robert Zangerle; Amy C. Justice; Timothy R. Sterling; Suzanne M Ingle; Jonathan A C Sterne

Summary Background Health care for people living with HIV has improved substantially in the past two decades. Robust estimates of how these improvements have affected prognosis and life expectancy are of utmost importance to patients, clinicians, and health-care planners. We examined changes in 3 year survival and life expectancy of patients starting combination antiretroviral therapy (ART) between 1996 and 2013. Methods We analysed data from 18 European and North American HIV-1 cohorts. Patients (aged ≥16 years) were eligible for this analysis if they had started ART with three or more drugs between 1996 and 2010 and had at least 3 years of potential follow-up. We estimated adjusted (for age, sex, AIDS, risk group, CD4 cell count, and HIV-1 RNA at start of ART) all-cause and cause-specific mortality hazard ratios (HRs) for the first year after ART initiation and the second and third years after ART initiation in four calendar periods (1996–99, 2000–03 [comparator], 2004–07, 2008–10). We estimated life expectancy by calendar period of initiation of ART. Findings 88 504 patients were included in our analyses, of whom 2106 died during the first year of ART and 2302 died during the second or third year of ART. Patients starting ART in 2008–10 had lower all-cause mortality in the first year after ART initiation than did patients starting ART in 2000–03 (adjusted HR 0·71, 95% CI 0·61–0·83). All-cause mortality in the second and third years after initiation of ART was also lower in patients who started ART in 2008–10 than in those who started in 2000–03 (0·57, 0·49–0·67); this decrease was not fully explained by viral load and CD4 cell count at 1 year. Rates of non-AIDS deaths were lower in patients who started ART in 2008–10 (vs 2000–03) in the first year (0·48, 0·34–0·67) and second and third years (0·29, 0·21–0·40) after initiation of ART. Between 1996 and 2010, life expectancy in 20-year-old patients starting ART increased by about 9 years in women and 10 years in men. Interpretation Even in the late ART era, survival during the first 3 years of ART continues to improve, which probably reflects transition to less toxic antiretroviral drugs, improved adherence, prophylactic measures, and management of comorbidity. Prognostic models and life expectancy estimates should be updated to account for these improvements. Funding UK Medical Research Council, UK Department for International Development, EU EDCTP2 programme.

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Peter Reiss

University of Amsterdam

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Luuk Gras

University of Amsterdam

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Caroline Sabin

University College London

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