National Center in Epidemiology and Clinical Research

Sydney, Australia

National Center in Epidemiology and Clinical Research

Sydney, Australia
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Falster K.,National Center in Epidemiology and Clinical Research | Falster K.,University of New South Wales | Wand H.,National Center in Epidemiology and Clinical Research | Donovan B.,National Center in Epidemiology and Clinical Research | And 4 more authors.
AIDS | Year: 2010

OBJECTIVES: To describe hospitalization rates, risk factors and associated diagnoses in people with HIV in Australia between 1999 and 2007. DESIGN: Retrospective cohort study of people with HIV (n = 842) using data linkage between the Australian HIV Observational Database and administrative hospital morbidity data collections. METHODS: Incidence rate ratios with 95% confidence intervals were estimated using Poisson regression models to assess risk factors for hospitalization. Predictors of length of stay were assessed using generalized mixed models. The association between hospitalization and mortality was assessed using Cox regression. RESULTS: In 4519 person-years of observation, there were 2667 hospital admissions; incidence rate of 59 per 100 person-years. Hospitalization rates were 50-300% higher in this cohort than comparable age and sex strata in the general population. Older age (incidence rate ratio 1.46, 95% confidence interval 1.28-1.65 per 10-year increase) and prior AIDS (incidence rate ratio 1.71, 95% confidence interval 1.24-2.35) were significantly associated with hospitalization. Other predictors of hospitalization included lower CD4 cell counts, higher HIV RNA, longer duration of HIV infection and experience with more drug classes. Lower CD4 cell counts, older age and hepatitis C virus antibody positivity were independently associated with longer hospital stay. Non-AIDS diseases were the principle reason for admission in the majority of cases. Mortality was associated with more frequent hospitalization during the study period. CONCLUSION: Hospitalization rates are higher in people with HIV than the general population in Australia and are associated with markers of advanced HIV disease despite the widespread use of combination antiretroviral therapy. © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins.

Worm S.W.,Copenhagen University | Weber R.,University of Zürich | Reiss P.,HIV Monitoring Foundation | El-Sadr W.,Columbia University | And 9 more authors.
Journal of Infectious Diseases | Year: 2010

Background. The risk of myocardial infarction (MI) in patients with human immunodeficiency virus (HIV) infection has been assessed in 13 anti-HIV drugs in the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study. Methods. Poisson regression models were adjusted for cardiovascular risk factors, cohort, calendar year, and use of other antiretroviral drugs and assessed the association between MI risk and cumulative (per year) or recent (current or in the past 6 months) use of antiretroviral drugs, with >30,000 person-years of exposure. Results. Over 178,835 person-years, 580 patients developed MI. There were no associations between use of tenofovir, zalcitabine, zidovudine, stavudine, or lamivudine and MI risk. Recent exposure to abacavir or didanosine was associated with an increased risk of MI. No association was found between MI risk and cumulative exposure to nevirapine, efavirenz, nelfinavir, or saquinavir. Cumulative exposure to indinavir and lopinavir-ritonavir was associated with an increased risk of MI (relative rate [RR] per year, 1.12 and 1.13, respectively). These increased risks were attenuated slightly (RR per year, 1.08 [95% confidence interval {CI}, 1.02-1.14] and 1.09 [95% CI, 1.01-1.17], respectively) after adjustment for lipids but were not altered further after adjustment for other metabolic parameters. Conclusions. Of the drugs considered, only indinavir, lopinavir-ritonavir, didanosine, and abacavir were associated with a significantly increased risk of MI. As with any observational study, our findings must be interpreted with caution (given the potential for confounding) and in the context of the benefits that these drugs provide. © 2009 by the Infectious Diseases Society of America. All rights reserved.

Kong F.Y.S.,Burnet Institute | Guy R.J.,National Center in Epidemiology and Clinical Research | Hocking J.S.,University of Melbourne | Merritt T.,Hunter New England Population Health | And 5 more authors.
Medical Journal of Australia | Year: 2011

Objective: To describe the proportion of 16-29-year-olds tested for chlamydia by Australian general practitioners in a 12-month period. Design and setting: Between October 2007 and September 2008, the national chlamydia testing rate in 16-29-year-olds was calculated by dividing the number of Medicare-reimbursed chlamydia tests by two denominators: (i) Medicare-reimbursed GP consultations; and (ii) estimated resident populations adjusted for the proportion who were sexually active. Main outcome measures: GP chlamydia testing rates in 16-29-year-olds per 100 patients attending a GP consultation and per 100 sexually active population, by patient age and sex, state/territory of residence, and remoteness area. Results: Among the estimated Australian population of 16-29-year-olds, 85.6% of females and 64.4% of males had at least one GP consultation in the 12-month period. The national GP chlamydia testing rate per 100 patients was 8.9% (95% CI, 8.88%-8.94%). The national GP chlamydia testing rate per 100 sexually active population was 8.0% (95% CI, 7.92%-7.98%). The rate per 100 sexually active population was higher in females (12.5%) compared with males (3.7%) (P < 0.01); higher in 20-24-year-olds (9.0%) compared with 16-19-year-olds (8.7%) and 25-29-year-olds (6.6%) (P < 0.01); higher in those living in non-metropolitan areas (11.0%) compared with metropolitan areas (8.4%) (P < 0.01); and highest in those living in the Northern Territory (21.4%) compared with other jurisdictions (P < 0.01). Conclusions: Despite clinical guidelines recommending annual chlamydia testing for sexually active 15-29-year-olds, our analysis showed that a high proportion of young people aged 16-29 years attend a GP each year, but few of the sexually active population in this age group were tested for chlamydia in general practice. Strategies are needed to support GPs to enhance chlamydia testing in young people.

Merrall E.L.C.,MRC Biostatistics Unit | Kariminia A.,National Center in Epidemiology and Clinical Research | Binswanger I.A.,University of Colorado at Denver | Binswanger I.A.,Denver Health Medical Center | And 7 more authors.
Addiction | Year: 2010

Aims The transition from prison back into the community is particularly hazardous for drug-using offenders whose tolerance for heroin has been reduced by imprisonment. Studies have indicated an increased risk of drug-related death soon after release from prison, particularly in the first 2 weeks. For precise, up-to-date understanding of these risks, a meta-analysis was conducted on the risk of drug-related death in weeks 1 + 2 and 3 + 4 compared with later 2-week periods in the first 12 weeks after release from prison. Methods English-language studies were identified that followed up adult prisoners for mortality from time of index release for at least 12 weeks. Six studies from six prison systems met the inclusion criteria and relevant data were extracted independently. Results These studies contributed a total of 69 093 person-years and 1033 deaths in the first 12 weeks after release, of which 612 were drug-related. A three- to eightfold increased risk of drug-related death was found when comparing weeks 1 + 2 with weeks 3-12, with notable heterogeneity between countries: United Kingdom, 7.5 (95% CI: 5.7-9.9); Australia, 4.0 (95% CI: 3.4-4.8); Washington State, USA, 8.4 (95% CI: 5.0-14.2) and New Mexico State, USA, 3.1 (95% CI: 1.3-7.1). Comparing weeks 3 + 4 with weeks 5-12, the pooled relative risk was: 1.7 (95% CI: 1.3-2.2). Conclusions These findings confirm that there is an increased risk of drug-related death during the first 2 weeks after release from prison and that the risk remains elevated up to at least the fourth week. © 2010 Society for the Study of Addiction.

Pedrana A.E.,Burnet Institute | Pedrana A.E.,Monash University | Hellard M.E.,Burnet Institute | Hellard M.E.,Monash University | And 5 more authors.
Journal of Acquired Immune Deficiency Syndromes | Year: 2012

Undiagnosed HIV infections contribute disproportionately to the HIV epidemic. We recruited 639 gay men attending social venues, who completed a cross-sectional survey with oral fluid collection for HIV testing in 2008. We calculated HIV and undiagnosed HIV prevalence and used χ 2 tests and logistic regression to examine associations between participant characteristics and HIV status. Among 639 men, 61 (9.5%, 95% confidence interval: 7.4% to 12.1%) tested HIV positive, of which 19 (31.1%, 95%confidence interval: 19.9% to 44.3%) were classified as undiagnosed HIV positive. Almost a third of HIV-positive men were unaware of their HIV status, and of these men, a large proportion engaged in high-risk behaviors.

Hocking J.S.,University of Melbourne | Stein A.,CSL Ltd | Conway E.L.,CSL Ltd | Regan D.,University of New South Wales | And 3 more authors.
British Journal of Cancer | Year: 2011

Background: Although tobacco- and alcohol-associated head and neck cancers are declining in the developed world, potentially human papillomavirus (HPV)-associated oropharnygeal cancers are increasing. Methods: We analysed oropharyngeal and oral cavity cancer rates in Australia in 1982-2005. Cancers from the oropharynx (base of tongue, tonsil and other specific oropharyngeal sites) were classified as potentially HPV associated (n=8844); cancers in other oral cavity and oropharyngeal sites not previously associated with HPV were classified as comparison (n=28 379). Results: In 2000-2005, an average of 219, 159 and 110 cancers of the tonsil, base of tongue and other oropharyngeal sites were diagnosed annually, with incidences of 1.09 (95% CI: 1.03, 1.15), 0.79 (95% CI: 0.74, 0.84) and 0.55 (95% CI: 0.50, 0.59) per 100 000, respectively. An average of 1242 comparison cancers were diagnosed annually (6.17 (95% CI: 6.03, 6.31) per 100 000). In 1982-2005, there were significant annual increases in tonsil (1.39% (95% CI: 0.88, 1.92%)) and base of tongue cancers in males (3.02% (95% CI: 2.27, 3.78%)) and base of tongue cancer in females (3.45% (95% CI: 2.21, 4.70%)). There was a significant decrease in comparison cancers in men (1.69% (95% CI: 1.96, 1.42%)), but not in females. Conclusion: Potentially HPV-associated oropharyngeal cancer in Australia is increasing; the impact of HPV vaccination on these cancers should be monitored. © 2011 Cancer Research UK All rights reserved.

Wand H.,National Center in Epidemiology and Clinical Research | Yan P.,Center for Infectious Disease Prevention and Control Population and Public Health Branch | Wilson D.,National Center in Epidemiology and Clinical Research | McDonald A.,National Center in Epidemiology and Clinical Research | And 3 more authors.
HIV Medicine | Year: 2010

Objectives: The aim of the study was to reconstruct the HIV epidemic in Australia for selected populations categorized by exposure route; namely, transmission among men who have sex with men (MSM), transmission among injecting drug users (IDUs), and transmission among heterosexual men and women in Australia. Design: Statistical back-projection techniques were extended to reconstruct the historical HIV infection curve using surveillance data. Methods: We developed and used a novel modified back-projection modelling technique that makes maximal use of all available surveillance data sources in Australia, namely, (1) newly diagnosed HIV infections, (2) newly acquired HIV infections and (3) AIDS diagnoses. Results: The analyses suggest a peak HIV incidence in Australian MSM of ∼2000 new infections per year in the late 1980s, followed by a rapid decline to a low of <500 in the early 1990s. We estimate that, by 2007, cumulatively ∼20 000 MSM were infected with HIV, of whom 13% were not diagnosed with HIV infection. Similarly, a total of ∼1050 and ∼2600 individuals were infected through sharing needles and heterosexual contact, respectively, and in 12% and 23% of these individuals, respectively, the infection remained undetected. Discussion: Male homosexual contact accounts for the majority of new HIV infections in Australia. However, the transmission route distribution of new HIV infections has changed over time. The number of HIV infections is increasing substantially among MSM, increasing moderately in those infected via heterosexual exposure, and decreasing in IDUs. © 2010 British HIV Association.

Bourne C.,Sydney Hospital | Bourne C.,University of New South Wales | Knight V.,Sydney Hospital | Guy R.,National Center in Epidemiology and Clinical Research | And 4 more authors.
Sexually Transmitted Infections | Year: 2011

Objectives: To evaluate the impact of a short message service (SMS) reminder system on HIV/sexually transmitted infection (STI) re-testing rates among men who have sex with men (MSM). Methods: The SMS reminder programme started in late 2008 at a large Australian sexual health clinic. SMS reminders were recommended 3-6 monthly for MSM considered high-risk based on self-reported sexual behaviour. The evaluation compared HIV negative MSM who had a HIV/STI test between 1 January and 31 August 2010 and received a SMS reminder (SMS group) with those tested in the same time period (comparison group) and pre-SMS period (pre-SMS group, 1 January 2008 and 31 August 2008) who did not receive the SMS. HIV/STI re-testing rates were measured within 9 months for each group. Baseline characteristics were compared between study groups and multivariate logistic regression used to assess the association between SMS and re-testing and control for any imbalances in the study groups. Results: There were 714 HIV negative MSM in the SMS group, 1084 in the comparison group and 1753 in the pre-SMS group. In the SMS group, 64% were re-tested within 9 months compared to 30% in the comparison group (p<0.001) and 31% in the pre-SMS group (p<0.001). After adjusting for baseline differences, re-testing was 4.4 times more likely (95% CI 3.5 to 5.5) in the SMS group than the comparison group and 3.1 times more likely (95% CI 2.5 to 3.8) than the pre-SMS group. Conclusion: SMS reminders increased HIV/STI re-testing among HIV negative MSM. SMS offers a cheap, efficient system to increase HIV/STI re-testing in a busy clinical setting.

Wand H.,National Center in Epidemiology and Clinical Research | Ramjee G.,HIV Prevention Research Unit
Journal of the International AIDS Society | Year: 2010

Background. In South Africa, the severity of the HIV/AIDS epidemic varies according to geographical location; hence, localized monitoring of the epidemic would enable more effective prevention strategies. Our objectives were to assess the core areas of HIV infection in KwaZulu-Natal, South Africa, using epidemiological data among sexually active women from localized communities. Methods. A total of 5753 women from urban, peri-rural and rural communities in KwaZulu-Natal were screened from 2002 to 2005. Each participant was geocoded using a global information system, based on residence at time of screening. The Spatial Scan Statistics programme was used to identify areas with disproportionate excesses in HIV prevalence and incidence. Results. This study identified three hotspots with excessively high HIV prevalence rates of 56%, 51% and 39%. A total of 458 sexually active women (19% of all cases) were included in these hotspots, and had been exclusively recruited by the Botha's Hill (west of Durban) and Umkomaas (south of Durban) clinic sites. Most of these women were Christian and Zulu-speaking. They were also less likely to be married than women outside these areas (12% vs. 16%, p = 0.001) and more likely to have sex more than three times a week (27% vs. 20%, p < 0.001) and to have had more than three sexual partners (55% vs. 45%, p < 0.001). Diagnosis of genital herpes simplex virus type 2 was also more common in the hotspots. This study also identified areas of high HIV incidence, which were broadly consistent with those with high prevalence rates. Conclusions. Geographic excesses of HIV infections at rates among the highest in the world were detected in certain rural communities of Durban, South Africa. The results reinforce the inference that risk of HIV infection is associated with definable geographical areas. Localized monitoring of the epidemic is therefore essential for more effective prevention strategies - and particularly urgent in a region such as KwaZulu-Natal, where the epidemic is particularly rampant. © 2010 Wand and Ramjee; licensee BioMed Central Ltd.

Wand H.,National Center in Epidemiology and Clinical Research | Whitaker C.,HIV Prevention Research Unit | Ramjee G.,HIV Prevention Research Unit
International Journal of Health Geographics | Year: 2011

Background: The severity of the HIV/AIDS epidemic in South Africa varies between and within provinces, with differences noted even at the suburban scale. We investigated the geographical variability of HIV infection in rural areas of the eThekwini Metropolitan Municipality in KwaZulu-Natal province, South Africa.Method: We used geoadditive models to assess nonlinear geographical variation in HIV prevalence while simultaneously controlling for important demographic and sexual risk factors. A total of 3,469 women who were screened for a Phase-III randomized trial were included in the current analysis.Results: We found significant spatial patterns that could not be explained by demographic and sexual risk behaviors. In particular, the epidemic was determined to be much worse 44 km south of Durban after controlling for all demographic and sexual risk behaviors.Conclusion: The study revealed significant geographic variability in HIV infection in the eThekwini Metropolitan Municipality in KwaZulu-Natal, South Africa. © 2011 Wand et al; licensee BioMed Central Ltd.

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