Heather F Gidding

University of New South Wales, Kensington, New South Wales, Australia

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Publications (73)172.23 Total impact

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    ABSTRACT: SUMMARY In Australia, hepatitis B (HBV) vaccination is recommended for injecting drug users (IDUs), Indigenous adults and prisoners. We compared immunity to HBV in prisoners and the general population obtained from national serosurveys in 2007. Individuals with HBV surface antibody (HBsAb) positive sera were considered immune from past infection [HBV core antibody (HBcAb) positive] or from vaccination (HBcAb negative). Male prisoners aged 18-58 years had a higher HBsAb seroprevalence than the general population (46·4% vs. 39·4%, P = 0·061). Comparison of HBcAb results was possible for males aged 18-29 years. In this group, higher HBsAb seroprevalence was due to past infection (12·9% vs. 3·0%, P < 0·001), rather than vaccine-conferred immunity (35·3% vs. 43·4%, P = 0·097). All prisoner groups, but especially IDUs, those of Indigenous heritage or those with a previous episode of imprisonment had higher levels of immunity from past infection than the general population (19·3%, 33·0%, 17·1%, respectively, vs. 3·0%, P < 0·05). Indigenous prisoners, non-IDUs and first-time entrants had significantly lower levels of vaccine-conferred immunity than the general population (26·4%, 26·2% and 20·7% respectively vs. 43·4%, P < 0·05). Improving prison-based HBV vaccination would prevent transmission in the prison setting and protect vulnerable members of the community who are at high risk of both infection and entering the prison system.
    Epidemiology and infection. 01/2015;
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    ABSTRACT: Febrile seizures (FS) are common in childhood with incidence peaking in the second year of life when measles and varicella-containing vaccines are administered. This study aimed to examine the vaccine-attributable risk of FS following separate administration of MMR and monovalent varicella vaccines (VV) prior to a planned change to MMRV as the second dose of measles-containing vaccine at 18 months of age. All FS cases in children aged <5 years from 1st January 2012 to 30th April 2013 were identified from emergency department (ED) and inpatient databases at five Australian tertiary paediatric hospitals participating in PAEDS (Paediatric Active Enhanced Disease Surveillance). Immunization records were obtained from the Australian Childhood Immunization Register (ACIR). The relative incidence (RI) of FS following MMR dose 1 (MMR1) and VV in children aged 11-23 months was determined using the self-controlled case series (SCCS) method and used to calculate attributable risk. There were 2013 FS episodes in 1761 children. The peak age at FS was 18 months. The risk of FS was significantly increased 5-12 days post receipt of MMR1 at 12 months (RI=1.9 [95% CI: 1.3-2.9]), but not after VV at 18 months (RI=0.6 [95% CI: 0.3-1.2]. The estimated excess annual number of FS post MMR1 was 24 per 100,000 vaccinated children aged 11-23 months (95% CI=7-49 cases per 100,000) or 1 per 4167 doses. Our study detected the expected increased FS risk post MMR1 vaccine at 12 months, but monovalent varicella vaccine at age 18 months was not associated with increased risk of FS. This provides baseline data to assess the risk of FS post MMRV, introduced in Australia as the second dose of measles-containing vaccine at 18 months of age in July 2013. Copyright © 2014. Published by Elsevier Ltd.
    Vaccine 11/2014; · 3.49 Impact Factor
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    ABSTRACT: SUMMARY In Australia, varicella vaccine was universally funded in late 2005 as a single dose at 18 months. A school-based catch-up programme for children aged 10-13 years without a history of infection or vaccination was funded until 2015, when those eligible for universal infant vaccination would have reached the age of high school entry. This study projects the impact of discontinuing catch-up vaccination on varicella and zoster incidence and morbidity using a transmission dynamic model, in comparison with alternative policy options, including two-dose strategies. At current vaccine coverage (83% at 2 years and 90% at 5 years), ceasing the adolescent catch-up programme in 2015 was projected to increase varicella-associated morbidity between 2035 and 2050 by 39%. Although two-dose infant programmes had the lowest estimated varicella morbidity, the incremental benefit from the second dose fell by 70% if first dose coverage increased from 83% to 95% by age 24 months. Overall zoster morbidity was predicted to rise after vaccination, but differences between strategies were small. Our results suggest that feasibility of one-dose coverage approaching 95% is an important consideration in estimating incremental benefit from a second dose of varicella vaccine.
    Epidemiology and Infection 09/2014; · 2.49 Impact Factor
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    ABSTRACT: While the importance of record linkage is widely recognised, few studies have attempted to quantify how linkage errors may have impacted on their own findings and outcomes. Even where authors of linkage studies have attempted to estimate sensitivity and specificity based on subjects with known status, the effects of false negatives and positives on event rates and estimates of effect are not often described.
    PLoS ONE 07/2014; 9(7):e103690. · 3.53 Impact Factor
  • A Dey, H F Gidding, R Menzies, P McIntyre
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    ABSTRACT: In 2010, use of seasonal trivalent influenza vaccine (TIV) in children <5 years of age was suspended in Australia following reports of vaccine-related febrile convulsions. We investigated the utility of data on primary care [general practice (GP)] consultations for any reason within three days of receipt of influenza vaccine as recorded on the Australian Childhood Immunisation Register (ACIR) as a means of signal detection. Data on GP consultations were obtained from Medicare Australia (Australian Government Department of Human Services) for children recorded on the ACIR as receiving either TIV or monovalent influenza vaccine. Rates of GP consultation by day following ACIR-recorded receipt of influenza vaccine were compared by year (2008-2010), vaccine type, age and region. In 2010, GP encounter rates on the day after receipt of the TIV manufactured by bioCSL (formerly CSL Biotherapies (Fluvax(®)) were significantly higher than both bioCSL TIVs in the previous two years [rate ratio (RR) 1.9; 95% CI: 1.7-2.2] and Sanofi Pasteur TIV, Vaxigrip(®) [RR 1.6, 95% CI 1.4-1.7] in 2009-2010. Encounter rates were also higher than for CSL Monovalent influenza vaccine, Panvax(®) [RR 1.9, 95% CI 1.7-2.2] in 2009-2010. These findings were robust to adjustment for age group (≤2, >2 years) and region (Western Australia vs other Australian states/territories). A primary care consultation on the day after vaccine receipt is a reasonable proxy for early reactogenicity and has potential for use in various settings.
    Vaccine 03/2014; · 3.49 Impact Factor
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    ABSTRACT: To estimate the measles effective reproduction number (R) in Australia by modelling routinely collected notification data. R was estimated for 2009-2011 by means of three methods, using data from Australia's National Notifiable Disease Surveillance System. Method 1 estimated R as 1 - P, where P equals the proportion of cases that were imported, as determined from data on place of acquisition. The other methods estimated R by fitting a subcritical branching process that modelled the spread of an infection with a given R to the observed distributions of outbreak sizes (method 2) and generations of spread (method 3). Stata version 12 was used for method 2 and Matlab version R2012 was used for method 3. For all methods, calculation of 95% confidence intervals (CIs) was performed using a normal approximation based on estimated standard errors. During 2009-2011, 367 notifiable measles cases occurred in Australia (mean annual rate: 5.5 cases per million population). Data were 100% complete for importation status but 77% complete for outbreak reference number. R was estimated as < 1 for all years and data types, with values of 0.65 (95% CI: 0.60-0.70) obtained by method 1, 0.64 (95% CI: 0.56-0.72) by method 2 and 0.47 (95% CI: 0.38-0.57) by method 3. The fact that consistent estimates of R were obtained from all three methods enhances confidence in the validity of these methods for determining R.
    Bulletin of the World Health Organisation 03/2014; 92(3):171-7. · 5.11 Impact Factor
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    ABSTRACT: Background Management of prelabour rupture of membranes at term (37 weeks gestation or later) (TPROM) remains complicated in the absence of a rapid assay for group B streptococcus (GBS) colonisation. AimsTo evaluate the accuracy and clinical utility of a commercial PCR assay, compared with culture, for detection of GBS colonisation in pregnant women presenting with TPROM. MethodsA prospective study of women presenting with TPROM conducted in a large tertiary hospital (Westmead Hospital, Australia). Five hundred and seventy-four consecutive women with TPROM were enrolled between July 2006 and November 2007. Paired low vaginal and anal swabs were collected from women presenting with TPROM for PCR and culture on GBS selective agar following broth enrichment. Primary outcomes were sensitivity and specificity of PCR compared with GBS selective enrichment culture. Secondary analyses included comparison with a historical but otherwise similar cohort regarding clinical utility, maternal and neonatal outcomes. ResultsPCR sensitivity and specificity were 89.0% (95% CI – 82.8–93.6%) and 97.9% (95% CI – 96.0–99.0%), respectively, compared with culture. 72.3% of women were aware of their GBS PCR status within 3 h of presentation. Compared with the historical cohort, PCR reduced the requirement for intrapartum antibiotics by 25.6% (P < 0.001). There were no significant differences in maternal outcomes or combined rates of admissions to neonatal intensive care or special care nursery. Conclusions Group B streptococcus PCR is an accurate, rapid, safe and practical alternative to culture for detection of GBS colonisation in pregnant women at the time of TPROM. This method has the potential advantage to reduce costs associated with length of hospital stay.
    Australian and New Zealand Journal of Obstetrics and Gynaecology 11/2013; · 1.30 Impact Factor
  • Joanne Reekie, Heather F Gidding, John M Kaldor, Bette Liu
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    ABSTRACT: BACKGROUND AND AIM: While hepatitis B (HBV) prevalence is known to vary greatly between countries, systematically collected population-level prevalence data from some countries is limited. Antenatal HBV screening programs in countries with substantial migrant populations provide the opportunity to systematically examine HBV prevalence in order to inform local and regional HBV estimates. METHODS: A comprehensive register of Australian mothers giving birth from January 2000 to December 2008 was linked to a register of HBV notifications. Age standardized prevalence of chronic HBV were calculated overall and by the mother's country of birth. Multiple logistic regression was used to investigate other factors associated with HBV prevalence. RESULTS: 523,665 women were included and linked to 3,861 HBV notifications. The age-standardized HBV prevalence was low (0.75%, 95%CI 0.72-0.79). The highest HBV prevalence rates were observed in women born in Cambodia (8.60%), Taiwan (8.10%), Vietnam (7.49%), China (6.80%), and Tonga (6.51%). Among Australian born women, those who smoked during pregnancy, were from a more disadvantaged socioeconomic background, and lived in remote areas were more likely to have HBV. There was also a trend suggesting a decrease in the prevalence of HBV over time. CONCLUSIONS: Antenatal screening for HBV can provide systematic population estimates of HBV prevalence in migrants and also identify other high prevalence groups. Longer follow-up will be required to confirm the small decrease in HBV prevalence observed in this study.
    Journal of Gastroenterology and Hepatology 04/2013; · 3.33 Impact Factor
  • Heather F Gidding, Stephen R Graves
    The Medical journal of Australia 01/2013; 198(1):9-10. · 2.85 Impact Factor
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    S Oftadeh, H F Gidding, G L Gilbert
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    ABSTRACT: SUMMARY We compared serotype distributions of Streptococcus pneumoniae isolates from patients aged <5 and ⩾5 years with invasive pneumococcal disease in New South Wales, Australia, and antibiotic susceptibilities of isolates from the <5 years age group only, before (2002-2004) and after (2005-2009) introduction of the 7-valent pneumococcal conjugate vaccine (PCV7). Overall, there were significant decreases in the mean annual number of referred isolates (770 vs. 515) and the proportion belonging to PCV7 serotypes (74% vs. 38%), but non-PCV7 serotypes, particularly 19A, increased (5% vs. 18%). All changes were more marked in the <5 years age group. Susceptibility testing of isolates from the <5 years age group showed variation in resistance between serotypes, but significant overall increases in penicillin non-susceptibility (23% vs. 31%), ceftriaxone resistance (2% vs. 12%) and multidrug resistance (4% vs. 7%) rates; erythromycin resistance fell (32% vs. 25%). Continued surveillance is needed to monitor changes following the introduction of 13-valent PCV in 2012.
    Epidemiology and Infection 09/2012; · 2.49 Impact Factor
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    ABSTRACT: Serological data provide an important measure of past exposure and immunity to hepatitis A virus (HAV) infection in a population. National serosurveys from developed countries have typically indicated a decline in HAV seroprevalence over time as sanitation levels improve. We examined trends in the seroepidemiology of HAV antibodies in Victoria, Australia, drawing on cross-sectional samples taken at three time points over a 20-year period. Stored sera from 1988 (n=753), 1998 (n=1091), and 2008 (n=791) from persons aged 1-69 years were obtained from the state of Victoria, Australia. The within-year population adjusted results show a significant trend of increasing population HAV seroprevalence over time from 34.3% (95% CI 31.7-36.9) in 1988, to 40.0% (95% CI 37.1-42.8) in 1998 and 55.1% (95% CI 52.1-58.1) in 2008, P<0.0001. A particularly noticeable rise in population seroprevalence was observed between 1998 and 2008 for those aged 5-39 years. The increase in HAV seropositivity over time is in contrast to the declining rates of disease notification in Australia. Based on comparisons with other Australian data, it appears the increase in population seroprevalence over the last two decades is unlikely to be due to endemic transmission of infection. Instead, other factors, including increases in travel to HAV endemic regions, migration to Australia from HAV endemic regions and vaccine uptake are more likely causes. Ongoing monitoring of serological HAV profiles in the population is required to determine future policy direction to prevent increased burden.
    Vaccine 08/2012; 30(42):6020-6. · 3.49 Impact Factor
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    ABSTRACT: Antibiotic homogeneity is thought to drive resistance but in vivo data are lacking. In this study, we determined the impact of antibiotic homogeneity per se, and of cefepime versus antipseudomonal penicillin/β-lactamase inhibitor combinations (APP-β), on the likelihood of infection or colonisation with antibiotic resistant bacteria and/or two commonly resistant nosocomial pathogens (methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa). A secondary question was whether antibiotic cycling was associated with adverse outcomes including mortality, length of stay, and antibiotic resistance. We evaluated clinical and microbiological outcomes in two similar metropolitan ICUs, which both alternated cefepime with APP-β in four-month cycles. All microbiological isolates and commensal samples were analysed for the presence of antibiotic-resistant bacteria including MRSA and P. aeruginosa. Length of stay, mortality and overall antibiotic resistance were unchanged after sixteen months. However, increased colonisation and infection by antibiotic-resistant bacteria were observed in cefepime cycles, returning to baseline in APP-β cycles. Cefepime was the strongest risk factor for acquisition of antibiotic-resistant infection. Ecological effects of different β-lactam antibiotics may be more important than specific activity against the causative agents or the effect of antibiotic homogeneity in selection for antibiotic resistance. This has important implications for antibiotic policy.
    PLoS ONE 06/2012; 7(6):e38719. · 3.53 Impact Factor
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    ABSTRACT: To determine hepatitis C (HCV) treatment effectiveness and predictors of response in the "real-world" Australian clinic setting. Patients with chronic HCV, who were HCV-treatment-naive at enrolment, and were then treated with standard therapy (pegylated interferon-α plus ribavirin), were recruited prospectively through a national network of 24 HCV clinics between April 2008 and December 2009. Patients were interviewed and a medical record review was conducted at enrolment and at routine follow-up clinic visits. Proportion of patients achieving a sustained virological response (SVR), predictors of SVR, and impact of treatment on biochemical markers of liver disease (alanine aminotransferase levels and aspartate aminotransferase-to-platelet ratio index scores). The SVR by intention to treat was 60% (327/550). Infection with HCV genotype 2 or 3 (compared with genotype 1) was an independent predictor of SVR (odds ratio [OR], 2.45; 95% CI, 1.70-3.52), while HIV coinfection (OR, 0.28; 95% CI, 0.10-0.82), cirrhosis (OR, 0.38; 95% CI, 0.18-0.81), and increased body mass index for ≥ 30 kg/m(2) v ≤ 25 kg/m(2) (OR, 0.58; 95% CI, 0.35-0.96) were independently associated with lower SVR. There was a significant improvement in biochemical markers of liver disease following SVR (P< 0.001). Our findings are similar to those seen in clinical trials, despite the inclusion of patients with a broad range of comorbid conditions such as injecting drug and alcohol use and psychiatric illness. They suggest that, with appropriate patient and infrastructure support, expansion of treatment services to the broader HCV-infected community is warranted.
    The Medical journal of Australia 06/2012; 196(10):633-7. · 2.85 Impact Factor
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    ABSTRACT: Aim:  Little is known about the patterns of care and the impact of hepatocellular carcinoma (HCC) treatment on health outcomes at a population level. We conducted a population-based cohort study to examine HCC survival trends among people diagnosed with hepatitis B (HBV) or hepatitis C virus (HCV) infection, to determine predictors of receiving potentially curative therapy for HCC, and to examine the impact of HCC treatment on survival in New South Wales, Australia. Methods:  The Kaplan-Meier method was used to estimate survival, logistic regression to determine predictors of potentially curative therapy and Cox proportional hazards models to determine the impact of HCC treatment on survival. Years of potential life lost (YPLL) were calculated. Results:  During the period 1993-2007, 1081 cases of HCC were diagnosed. Median survival increased from 10.4 months during 1993-1997 to 18.4 months during 1998-2002, with no further improvement thereafter. Younger age at diagnosis (<65 years), being Asian-born and having multiple comorbid conditions increased the odds of receiving curative therapy. The effect of HCC treatment on the risk of mortality was similar between the HBV- and HCV-related HCC groups. Tumor-specific therapies had adjusted hazard ratios ranging 0.06-0.25 and palliative/supportive therapy alone had adjusted hazard ratios ranging 0.76-1.08. The average YPLL per person was 23.3. Conclusion:  The burden of viral hepatitis-related HCC is substantial. Despite treatment advances in recent years, there has been no significant improvement in HCC survival. Efforts to improve HCC screening and early diagnosis are required to deliver curative treatment which clearly has a survival advantage.
    Hepatology Research 04/2012; · 2.22 Impact Factor
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    ABSTRACT: Chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are the major risk factors for hepatocellular carcinoma (HCC). We examined trends in the incidence of HCC among a population-based cohort of people infected with HBV or HCV. HBV and HCV cases notified to the New South Wales Health Department between 1992 and 2007 were linked to the Central Cancer Registry, Registry of Births, Deaths and Marriages, and National HIV/AIDS Registries. Crude HCC incidence rates were estimated using person-time methodology. Age-standardized incidence rates were calculated using the 2001 Australian population. Trends in incidence were examined using join point regression models. Between 1992 and 2007, 1201 people had a linked HCC record: 556 of those with HBV; 592 with HCV; 45 with HBV/HCV co-infection; and 8 with HIV co-infection. The overall age-standardized HCC incidence rates declined non-significantly from 148.0 (95% confidence intervals (CI) 63.7, 287.4) per 100,000 population in 1995 to 101.2 (95% CI 67.3, 144.6) in 2007 among the HBV monoinfected group and significantly from 151.8 (95% CI 62.4, 299.8) per 100,000 population to 75.3 (95% CI 50.8, 105.5) among the HCV monoinfected group. However, incidence rates in the HCV monoinfected group progressively increased from the period 1992-1997 to 2004-2007 when adjusted for age, sex, and birth cohort, and the total number of cases per annum continued to increase. Despite declines in the age-adjusted incidence rates of HCC over time, the absolute number of cases increased likely due to the ageing cohort and an increasing prevalence of both hepatitis B and C in Australia.
    Journal of Viral Hepatitis 07/2011; 18(7):e232-41. · 3.08 Impact Factor
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    ABSTRACT: The incidence of hepatocellular carcinoma (HCC) has increased in Australia in recent decades, a large and growing proportion of which occurs among a population chronically infected with hepatitis B virus (HBV) or hepatitis C virus (HCV). However, risk factors for HCC among these high-risk groups require further characterization. We conducted a population-based cohort study using HBV and HCV cases notified to the New South Wales Health Department between 2000 and 2007. These were linked to cause of death data, HIV/AIDS notifications, and hospital records. Proportional hazards regression was used to identify significant risk factors for developing HCC. A total of 242 and 339 HCC cases were linked to HBV (n = 43 892) and HCV (n = 83 817) notifications, respectively. For both HBV and HCV groups, being male and increasing age were significantly associated with risk of HCC. Increasing comorbidity score indicated high risk, while living outside urban areas was associated with lower risk. Hazard ratios for males were two to three times those of females. For both HBV and HCV groups, cirrhosis, alcoholic liver disease, and the interaction between the two were associated with significantly and considerably elevated risk. This large population-based study confirms known risk factors for HCC. The association with older age highlights the potential impact of HBV and HCV screening of at-risk groups and early clinical assessment. Additional research is required to evaluate the impact of improving antiviral therapy on HCC risk.
    Journal of Gastroenterology and Hepatology 05/2011; 26(12):1757-64. · 3.33 Impact Factor
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    ABSTRACT: To determine uptake of treatment for hepatitis C virus (HCV) infection and predictors of deferral of treatment for HCV by using prospectively collected data from the Australian Chronic Hepatitis C Observational Study (ACHOS). Cohort study involving interview and medical record review at enrolment and routine follow-up clinic visits of patients with chronic HCV and compensated liver disease attending a national network of 24 HCV clinics between April 2008 and December 2009. Eligible patients were those who had not been previously treated, were enrolled within 6 months of their first clinic visit, were eligible for treatment and had been enrolled for at least 6 months. Predictors of patients undergoing HCV treatment within the first 6 months of assessment. 1239 patients were enrolled in ACHOS, of whom 406 met the criteria for inclusion in the subcohort for this study. Among this subcohort, 171 (42%) received treatment within 6 months of their first clinic visit. Current injecting drug use (odds ratio [OR], 0.26; 95% CI, 0.08-0.77), past and current treatment for drug dependency (OR, 0.34; 95% CI, 0.18-0.67, and OR, 0.42; 95% CI, 0.22-0.81, respectively) and alcohol use above 20 g/day (OR, 0.20; 95% CI, 0.08-0.46) were independent predictors of deferral of treatment. At least one of these factors applied to 41% of the subcohort. Clinical factors, including HCV genotype, HCV RNA level, and stage of liver disease were not associated with deferral of treatment for HCV. Factors related to drug and alcohol use, rather than clinical factors, influenced uptake of treatment for HCV. Further support for patients with drug and alcohol dependency is required to optimise treatment uptake.
    The Medical journal of Australia 04/2011; 194(8):398-402. · 2.85 Impact Factor
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    ABSTRACT: Previous studies have reported an excess burden of cancer and mortality in populations with chronic hepatitis B (HBV) or C (HCV), but there are limited data comparing hospitalization rates. In this study, we compared hospitalization rates for all causes and viral liver disease in people notified with HBV or HCV in New South Wales (NSW), Australia. HBV and HCV notifications were linked to their hospital (July 2000-June 2006), HIV and death records. Standardized hospitalization ratios (SHRs) were calculated using rates for the NSW population. Random effects Poisson regression was used to examine temporal trends. The SHR for all causes and non alcoholic liver disease was two-fold higher in the HCV cohort compared with the HBV cohort (SHRs 1.4 (95%CI: 1.4-1.4) v 0.6 (95%CI: 0.6-0.6) and 14.0 (95%CI: 12.7-15.4) v 5.4 (95%CI: 4.5-6.4), respectively), whilst the opposite was seen for primary liver cancer (SHRs 16.2 (95%CI: 13.8-19.1) v 29.1 (95%CI: 24.7-34.2)). HIV co-infection doubled the SHR except for primary liver cancer in the HCV/HIV cohort. In HBV and HCV mono-infected cohorts, all cause hospitalization rates declined and primary liver cancer rates increased, whilst rates for non alcoholic liver disease increased by 9% in the HCV cohort but decreased by 14% in the HBV cohort (P < 0.001). Hospital-related morbidity overall and for non alcoholic liver disease was considerably higher for HCV than HBV. Improved treatment of advanced HBV-related liver disease may explain why HBV liver-related morbidity declined. In contrast, HCV liver-related morbidity increased and improved treatments, especially for advanced liver disease, and higher levels of treatment uptake are required to reverse this trend.
    BMC Public Health 01/2011; 11:52. · 2.32 Impact Factor
  • H F Gidding, J Amin, G J Dore, M G Law
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    ABSTRACT: To determine the extent age, sex and co-infection affect morbidity in people infected with hepatitis C virus (HCV), we performed a population-based study linking HCV notifications in New South Wales, Australia with their hospital (July 2000 to June 2006), hepatitis B virus (HBV) and HIV notification, and death records. Poisson models were used to calculate hospitalization rate ratios (RRs) for all-cause, illicit drug and liver-related admissions. Co-infection RRs were used to estimate attributable risk (AR). The 86 501 people notified with HCV contributed 422 761 person-years of observation; 0·8% had HIV, 3·7% HBV, and 0·04% had both. RRs for males were equal to or lower than for females in younger ages, but higher in older ages (P for interaction ⩽0·013). HBV/HIV co-infection resulted in ARs of over 70% for liver disease and 30-60% otherwise. However, at the cohort level the impact was minimal (population ARs 1·3-8·7%). Our findings highlight the importance and success of public health measures, such as needle and syringe exchange programmes, which have helped to minimize the prevalence of co-infection in Australia. The findings also suggest that the age of study participants needs to be considered whenever the burden of HCV-related morbidity is reported by sex. The results are likely to be representative of patterns in hospital-related morbidity for the entire HCV-infected population in Australia and the ARs generalizable to other developed countries.
    Epidemiology and Infection 11/2010; 139(8):1151-8. · 2.49 Impact Factor
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    ABSTRACT: Chronic hepatitis B (HBV) or C (HCV) virus infection has been associated with increased risk of death, particularly from liver- and drug-related causes. We examined specific causes of death among a population-based cohort of people infected with HBV or HCV to identify areas of excess risk and examine trends in mortality. HBV and HCV cases notified to the New South Wales (NSW) Health Department between 1992 and 2006 were linked to cause of death data and HIV/AIDS notifications. Mortality rates and standardised mortality ratios (SMRs) were calculated using person time methodology, with NSW population rates used as a comparison. The study cohort comprised 42,480 individuals with HBV mono-infection and 82,034 with HCV mono-infection. HIV co-infection increased the overall mortality rate three to 10-fold compared to mono-infected groups. Liver-related deaths were associated with high excess risk of mortality in both HBV and HCV groups (SMR 10.0, 95% CI 9.0-11.1; 15.8, 95% CI 14.8-16.8). Drug-related deaths among the HCV group also represented an elevated excess risk (SMR 15.4, 95% CI 14.5-16.3). Rates of hepatocellular carcinoma (HCC)-related death remained steady in both groups. A decrease in non-HCC liver-related deaths was seen in the HBV group between 1997 and 2006, but not in the HCV group. After a sharp decrease between 1999 and 2002, drug-related mortality rates in the HCV group have been stable. Improvements in HBV treatment and uptake have most likely reduced non-HCC liver-related mortality. Encouragingly, HCV drug-related mortality remained low compared to pre-2002 levels, likely due to changes in opiate supply, and maintenance or improvement in harm reduction strategies.
    Journal of Hepatology 10/2010; 54(5):879-86. · 9.86 Impact Factor

Publication Stats

996 Citations
172.23 Total Impact Points


  • 2004–2014
    • University of New South Wales
      • School of Public Health and Community Medicine
      Kensington, New South Wales, Australia
  • 2001–2014
    • National Centre for Immunisation Research & Surveillance
      Sydney, New South Wales, Australia
  • 2005–2013
    • Westmead Hospital
      • Centre for Infectious Diseases and Microbiology
      Sydney, New South Wales, Australia
  • 2012
    • University of South Wales
      Понтиприте, Wales, United Kingdom
  • 2006–2010
    • Western Sydney Area Health Service
      Blacktown, New South Wales, Australia
  • 2001–2009
    • University of Sydney
      • Discipline of Paediatrics and Child Health
      Sydney, New South Wales, Australia
  • 2001–2005
    • Children's Hospital at Westmead
      • National Centre for Immunisation Research and Surveillance
      Sydney, New South Wales, Australia
  • 2002
    • Royal Alexandra Hospital
      Edmonton, Alberta, Canada
  • 1999
    • Queensland Health
      Brisbane, Queensland, Australia