Maternal Anaemia in Pregnancy: A Significantly Greater Risk Factor for Anaemia in Australian Aboriginal Children than Low Birth Weight or Prematurity.

OBJECTIVES: To identify maternal and perinatal risk factors associated with childhood anaemia. METHODS: A retrospective cohort study was conducted in three remote Katherine East Aboriginal communities in Northern Territory, Australia. Children born 2004-2014 in Community A and 2010-2014 in Community B and C, and their respective mothers were recruited into the study. Maternal and child data were linked to provide a longitudinal view of each child for the first 1000 days from conception to 2-years of age. Descriptive analyses were used to calculate mean maternal age, and proportions were used to describe other antenatal and perinatal characteristics of the mother/child dyads. The main outcome was the prevalence of maternal anaemia in pregnancy and risk factors associated with childhood anaemia at age 6 months. RESULTS: Prevalence of maternal anaemia in pregnancy was higher in the third trimester (62%) compared to the first (46%) and second trimesters (48%). There was a strong positive linear association (R2 = 0.46, p < 0.001) between maternal haemoglobin (Hb) in third trimester pregnancy and child Hb at age 6 months. Maternal anaemia in pregnancy (OR 4.42 95% CI 2.08-9.36) and low birth weight (LBW, OR 2.62, 95% CI 1.21-5.70) were associated with an increased risk of childhood anaemia at 6 months of age. CONCLUSIONS FOR PRACTICE: This is the first study to identify the association of maternal anaemia with childhood anaemia in the Australian Aboriginal population. A review of current policies and practices for anaemia screening, prevention and treatment during pregnancy and early childhood would be beneficial to both mother and child. Our findings indicate that administering prophylactic iron supplementation only to children who are born LBW or premature would be of greater benefit if expanded to include children born to anaemic mothers.

The high prevalence and impact of rheumatic heart disease in pregnancy in First Nations populations in a high-income setting: a prospective cohort study.

OBJECTIVE: To describe the epidemiology of rheumatic heart disease (RHD) in pregnancy in Australia and New Zealand (A&NZ). DESIGN: Prospective population-based study. SETTING: Hospital-based maternity units throughout A&NZ. POPULATION: Pregnant women with RHD with a birth outcome of ≥20 weeks of gestation between January 2013 and December 2014. METHODS: We identified eligible women using the Australasian Maternity Outcomes Surveillance System (AMOSS). De-identified antenatal, perinatal and postnatal data were collected and analysed. MAIN OUTCOME MEASURES: Prevalence of RHD in pregnancy. Perinatal morbidity and mortality. RESULTS: There were 311 pregnancies associated with women with RHD (4.3/10 000 women giving birth, 95% CI 3.9-4.8). In Australia, 78% were Aboriginal or Torres Strait Islander (60.4/10 000, 95% CI 50.7-70.0), while in New Zealand 90% were Maori or Pasifika (27.2/10 000, 95% CI 22.0-32.3). One woman (0.3%) died and one in ten was admitted to coronary or intensive care units postpartum. There were 314 births with seven stillbirths (22.3/1000 births) and two neonatal deaths (6.5/1000 births). Sixty-six (21%) live-born babies were preterm and one in three was admitted to neonatal intensive care or special care units. CONCLUSION: Rheumatic heart disease in pregnancy persists in disadvantaged First Nations populations in A&NZ. It is associated with significant cardiac and perinatal morbidity. Preconception planning and counselling and RHD screening in at-risk pregnant women are essential for good maternal and baby outcomes. TWEETABLE ABSTRACT: Rheumatic heart disease in pregnancy persists in First Nations people in Australia and New Zealand and is associated with major cardiac and perinatal morbidity.

Outcomes of primary myringoplasty in indigenous children from the Northern Territory of Australia.

AIM: To report the surgical and audiological outcomes of myringoplasty (Type I tympanoplasty) in Indigenous Australian children living in remote and regional communities in northern Australia. METHOD: An observational cohort study, with prospective recording of the details of surgery. Audiological outcomes were collected independently, and these data were integrated in the present study. Children aged 5-18 year underwent myringoplasty in the Northern Territory during a program initiated by the Australian Government. Surgery was performed by surgeons drawn from across Australia. RESULTS: 412 primary myringoplasties were performed. The mean age at surgery was 11 years. The tympanic membrane was closed in 64.2% of cases. Fascial grafting was associated with greater surgical success than cartilage. Dryness of the ear at surgery did not affect drum closure. Post-operative aural discharge was half that reported in historical literature. Surgical success was independent of the patient's age at surgery. Post-operative audiograms were available on 216 cases. At last review, hearing had improved even when the operation was not a surgical success, with hearing aid candidacy falling from 84 to 34%. Hearing was similar irrespective of the size of the perforation at surgery or the graft used and did not change with the time between surgery and review. The best hearing was associated with drum closure and Types A or C tympanograms. A conductive hearing loss persisted after surgery that was greater when there was an immobile drum. CONCLUSIONS: Indigenous children benefited from myringoplasty, even when the operation was not a "surgical success" as deemed by drum closure. There lower incidence of post-operative discharge from persistent perforations suggests an improvement in the ear health of the population. A persistent conductive loss persists, likely a consequence of the underlying disease but possibly from the surgery.

Does delay in planned diabetes care influence outcomes for aboriginal Australians? A study of quality in health care.

BACKGROUND: To examine the association between delay in planned diabetes care and quality of outcomes. METHODS: A retrospective analysis of primary care and inpatient records for 2567 Aboriginal patients, with diabetes, living in 49 remote communities in the Northern Territory of Australia. Poisson regression was used to estimate the association between delay from diagnosis to documented diabetes care plan and three outcome measures: mean HbA1c level, most recent blood pressure and number of diabetes-related hospital admissions. RESULTS: Compared with no delay (< 60 days), patients with delay had increased risk of elevated mean HbA1c: 60 days to < 2 years, incidence rate ratio (IRR), 1.2 (95% CI:1.07-1.39); 2 years to < 4 years, incidence rate ratio (IRR), 1.2 (95% CI:1.04-1.45); 4 years and over, incidence rate ratio (IRR), 1.3 (95% CI:1.12-1.52). There was no evidence of association between delay and optimal blood pressure control. Risk of diabetes-related admission increased with increased delay. Compared with no delay the IRRs for delay were: 60 days to < 2 years, 1.2 (95% CI:1.07-1.42); 2 to < 4 years, 1.3 (95% CI: 1.15-1.58): and 4 years and over, 2.6 (95% CI,2.28-3.08). CONCLUSION: The study found that a timely diabetes care plan was associated with better short-term blood glucose control and fewer diabetes-related admissions but not with improved blood pressure control. Delays may be a result of both patient and service-related factors.

Estimating the total prevalence and incidence of end-stage kidney disease among Aboriginal and non-Aboriginal populations in the Northern Territory of Australia, using multiple data sources.

BACKGROUND: Most estimates for End Stage Kidney Disease (ESKD) prevalence and incidence are based on renal replacement therapy (RRT) registers. However, not all people with ESKD will commence RRT and estimates based only on RRT registry data will underestimate the true burden of ESKD in the community. This study estimates the total number of Northern Territory (NT) residents with ESKD including: those receiving RRT, those diagnosed but not receiving RRT and an estimate of "undiagnosed" cases. METHODS: Four data sources were used to identify NT residents with a diagnosis of ESKD: public hospital admissions, Australia and New Zealand Dialysis and Transplant Registry registrations, death registrations and, for the Aboriginal population only, electronic primary care records. Three data sources contained information recorded between 1 July 2008 and 31 December 2013, death registration data extended to 31 December 2014 to capture 2013 prevalent cases. A capture-recapture method was used to estimate both diagnosed and undiagnosed cases by making use of probability patterns of overlapping multiple data sources. RESULTS: In 2013, the estimated ESKD prevalence in the NT Aboriginal population was 11.01 (95% confidence interval (CI) 10.24-11.78) per 1000, and 0.90 (95% CI 0.76-1.05) per 1000 in the NT non-Aboriginal population. The age-adjusted rates were 17.97 (95% CI 17.82-18.11) and 1.07 (95% CI 1.05-1.09) per 1000 in the NT Aboriginal and non-Aboriginal populations respectively. The proportion of individuals receiving RRT was 71.4% of Aboriginal and 75.5% of non-Aboriginal prevalent ESKD cases. The age-adjusted ESKD incidence was also greater for the Aboriginal (5.26 (95% CI 4.44-6.08) per 1000 population) than non-Aboriginal population (0.36 (95% CI 0.25-0.47) per 1000). CONCLUSION: This study provides comprehensive estimates of the burden of ESKD including those cases that are not identified in relevant health data sources. The results are important for informing strategies to reduce the total burden of ESKD and to manage the potential unmet demand, particularly from comparatively young Aboriginal patients who may be suitable for RRT but do not currently access the services for social, geographic or cultural reasons.

Patterns of paediatric emergency presentations to a tertiary referral centre in the Northern Territory.

OBJECTIVE: To describe epidemiological data concerning paediatric attendances at the ED of Royal Darwin Hospital (RDH). METHODS: We conducted a retrospective cohort study of paediatric emergency presentations to the RDH ED during 2004 and 2013. Epidemiological data, including demographics, admission rates and diagnostic grouping, were analysed using descriptive and comparative statistical methods. We compared data with findings from a baseline epidemiological study by the Paediatric Research in Emergency Departments International Collaborative (PREDICT) conducted in 2004. RESULTS: A total of 12 745 and 15 378 paediatric presentations (age 0-18 years) to the RDH ED were analysed for the years 2004 and 2013 respectively. In 2004, the mean age of children presenting to RDH was 7.1 years, and 56.0% were female. Indigenous patients accounted for 31.2% of presentations at RDH and were significantly more likely to be admitted than non-Indigenous patients (31.6% vs 12.8%, OR 3.24, 95% CI 2.95-3.55). Children <5 years old accounted for the highest number of presentations (45.2%) and admissions (51.2%), and there was a high proportion of adolescent presentations (18.0%). Similar to the PREDICT study, viral infectious conditions (bronchiolitis, gastroenteritis, upper respiratory tract infections) were the most common cause for presentations. Key differences included a higher proportion of patients presenting with cellulitis and head injury at RDH and an increasing proportion of adolescent psychiatric presentations at RDH from 2004 to 2013. CONCLUSION: This study provides important information regarding paediatric presentations to a major referral hospital in the Northern Territory. Overall, there was a disproportionate rate of presentation and admission among Indigenous children. Other key findings were higher proportions of cellulitis, head injury and adolescent presentations. These findings can assist in service planning and in directing future research specific to children in the Northern Territory.

The Alice Springs Hospital Readmission Prevention Project (ASHRAPP): a randomised control trial.

BACKGROUND: Hospitals are frequently faced with high levels of emergency department presentations and demand for inpatient care. An important contributing factor is the subset of patients with complex chronic diseases who have frequent and preventable exacerbations of their chronic diseases. Evidence suggests that some of these hospital readmissions can be prevented with appropriate transitional care. Whilst there is a growing body of evidence for transitional care processes in urban, non-indigenous settings, there is a paucity of information regarding rural and remote settings and, specifically, the indigenous context. METHODS: This randomised control trial compares a tailored, multidimensional transitional care package to usual care. The objective is to evaluate the efficacy of the transitional care package for Indigenous and non-Indigenous Australian patients with chronic diseases at risk of recurrent readmission with the aim of reducing readmission rates and improving transition to primary care in a remote setting. Patients will be recruited from medical and surgical admissions to Alice Springs Hospital and will be followed for 12 months. The primary outcome measure will be number of admissions to hospital with secondary outcomes including number of emergency department presentations, number of ICU admissions, days alive and out of hospital, time to primary care review post discharge and cost-effectiveness. DISCUSSION: Successful transition from hospital to home is important for patients with complex chronic diseases. Evidence suggests that a coordinated transitional care plan can result in a reduction in length of hospital stay and readmission rates for adults with complex medical needs. This will be the first study to evaluate a tailored multidimensional transitional care intervention to prevent readmission in Indigenous and non-Indigenous Australian residents of remote Australia who are frequently admitted to hospital. If demonstrated to be effective it will have implications for the care and management of Indigenous Australians throughout regional and remote Australia and in other remote, culturally and linguistically diverse populations and settings. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ACTRN12615000808549 - Retrospectively registered on 4/8/15.

A retrospective population-based study of induction of labour trends and associated factors among aboriginal and non-aboriginal mothers in the northern territory between 2001 and 2012.

BACKGROUND: Induction of labour (IOL) has become more common among many populations, but the trends and drivers of IOL in the Northern Territory (NT) of Australia are not known. This study investigated trends in IOL and associated factors among NT Aboriginal and non-Aboriginal mothers between 2001 and 2012. METHODS: A retrospective analysis of all NT resident women who birthed in the NT between 2001 and 2012 at ≥32 weeks gestation. Demographic, medical and obstetric data were obtained from the NT Midwives' Collection. The prevalence of IOL was calculated by Aboriginal status and parity of the mother and year of birth. The prevalence of each main indication for induction among women was compared for 2001-2003 and 2010-2012. Linear and logistic regression was used to test for association between predictive factors and IOL in bivariate and multivariate analysis, separately for Aboriginal and non-Aboriginal mothers. RESULTS: A total of 42,765 eligible births between 2001 and 2012 were included. IOL was less common for Aboriginal than non-Aboriginal mothers in 2001 (18.0 % and 25.1 %, respectively), but increased to be similar to non-Aboriginal mothers in 2012 (22.6 % and 24.8 %, respectively). Aboriginal primiparous mothers demonstrated the greatest increase in IOL. The most common indication for IOL for both groups was post-dates, which changed little over time. Medical and obstetric complications were more common for Aboriginal mothers except late-term pregnancy. Prevalence of diabetes in pregnancy increased considerably among both Aboriginal and non-Aboriginal mothers, but was responsible for only a small proportion of IOLs. Increasing prevalence of risk factors did not explain the increased IOL prevalence for Aboriginal mothers. CONCLUSIONS: IOL is now as common for Aboriginal as non-Aboriginal mothers, though their demographic, medical and obstetric profiles are markedly different. Medical indications did not explain the recent increase in IOL among Aboriginal mothers; changes in maternal or clinical decision-making may have been involved.

Effect of ambient temperature on Australian northern territory public hospital admissions for cardiovascular disease among indigenous and non-indigenous populations.

Hospitalisations are associated with ambient temperature, but little is known about responses in population sub-groups. In this study, heat responses for Indigenous and non-Indigenous people in two age groups were examined for two categories of cardiac diseases using daily hospital admissions from five Northern Territory hospitals (1992-2011). Admission rates during the hottest five per cent of days and the coolest five per cent of days were compared with rates at other times. Among 25-64 year olds, the Indigenous female population was more adversely affected by very hot days than the non-Indigenous female population, with admission rates for ischaemic heart disease (IHD) increasing by 32%. People older than 65 were more sensitive to cold, with non-Indigenous male admissions for heart failure increasing by 64%, and for IHD by 29%. For older Indigenous males, IHD admissions increased by 52% during cold conditions. For older non-Indigenous females, increases in admissions for heart failure were around 50% on these cold days, and 64% for older Indigenous females. We conclude that under projected climate change conditions, admissions for IHD amongst younger Indigenous people would increase in hot conditions, while admissions among elderly people during cold weather may be reduced. The responses to temperature, while showing significant relationships across the Northern Territory, may vary by region. These variations were not explored in this assessment.

Clustering in Northern Territory perinatal data for 2003-2005: implications for analysis and interpretation.

Clustering in perinatal data can violate assumptions of independence, an important consideration for data analysis. Few published studies report on the extent of repeat births in routinely collected Australian perinatal data and the implications thereof for analysis and interpretation. This paper reports on a case study that examined the extent and implications of clustering in the Northern Territory Midwives Collection (NTMC) for the period 2003-2005. Data were obtained on 7,741 individual mothers giving birth to 8,707 babies in public hospitals during 2003-2005. Clusters of multiple pregnancies and repeat births were identified and the design effects for birth weight of Aboriginal and non-Aboriginal newborns were calculated. Of the mothers, 46.1% were Aboriginal. Of these, 13.2% had repeat singleton births; 0.4% had multiple pregnancies, and 0.3% had both. Of non-Aboriginal mothers, 8.7% had repeat singleton births; 1.2% had multiple pregnancies; and 0.3% had both. The design effect was 1.07 for Aboriginal newborns and 1.04 for non-Aboriginal newborns. The design effects indicate that the correct variance accounting for clustering is 4-7% larger than the incorrect variance ignoring clustering when three consecutive years of NT data are considered and an intracluster correlation coefficient of 0.48 is assumed for birth weight between twin and non-twin siblings. Depending on the outcome of interest, the impact of clustering should be considered in multivariate analysis of perinatal data, especially when such analyses involve more than one year's data, include large proportions of Aboriginal mothers and newborns, and groups with different rates of repeat births.

Renal transplantation in indigenous Australians of the Northern Territory: closing the gap.

Chronic kidney disease causes high morbidity and mortality among Indigenous Australians of the Northern Territory (NT). Studies have shown chronic kidney disease rates of 4-10 times higher in indigenous than non-indigenous Australians and prevalent dialysis rates of 700-1200 per million population. For most patients with end-stage renal failure, renal transplantation provides the optimal treatment for people with end-stage renal disease. It reduces morbidity and mortality, and improves survival and quality of life. Graft and patient survival rates of over 80% at 5 years depending on the donor source (deceased vs living donor) are expected worldwide. However, this is not the case in Indigenous Australians of the NT where graft and patient survival are both around 50% at 5 years suggesting death with functioning graft as the most common cause of graft loss. It would provide the best treatment option for indigenous people most of who live in remote (18%) and very remote communities (63%). Many have to relocate from their communities to urban or regional centres for dialysis. Available options to avoid relocation include peritoneal dialysis, home haemodialysis and community health centre dialysis, but the acceptance rates for these are low, hence renal transplantation would provide the best option. There is evidence of identified barriers to renal transplantation for indigenous people of the NT. This review explores published data on why rates of renal transplantation in indigenous people of the NT are low and the reasons for poor outcomes highlighting possible areas of improvement.

A prospective study of neurocognitive changes 15 years after chronic inhalant abuse.

AIMS: In a previous study, neurological and cognitive deficits reflecting central nervous system (CNS) disruption from chronic inhalant abuse showed substantial recovery after 2 years' abstinence. Functional recovery was progressive, with recovery rates dependent on the degree of impairment prior to abstinence, and severity and duration of initial abuse. Persistent deficits occurred in those with previous 'lead encephalopathy' from leaded petrol abuse. The current study examined recovery in the same cohort 15 years after baseline. DESIGN: Prospective cohort design. SETTING: Two remote Aboriginal communities in Arnhem Land, Australia. PARTICIPANTS: Using baseline group classifications, 27 healthy controls, 60 ex-chronic inhalant abusers and an additional 17 with previous lead encephalopathy were assessed. MEASUREMENTS: Standard neurological, ocular-motor and cognitive functions and blood lead levels. FINDINGS: Chronic (non-encephalopathic) inhalant abusers showed elevated blood lead levels and abnormal scores on most tasks at baseline. At 2 years' abstinence, blood lead was reduced but remained elevated and most scores had normalized. By 15 years, blood lead and all performance scores were equivalent to healthy controls for this group (P > 0.05). The encephalopathic group was more severely impaired on all scores at baseline and showed little improvement, if any, across all tests after both 2 and 15 years' abstinence. Blood lead for this group declined, and was not significantly different to controls after 15 years. CONCLUSIONS: Some inhalant abusers experience severe and persistent neurological deficits, suggesting irrecoverable damage attributable to lead encephalopathy. In the absence of this encephalopathy long-term abstinence from inhalants may allow recovery of normal brain function.

Validation and enhancement of Australian Aboriginal and Torres Strait Islander psychiatric hospitalisation statistics through an Indigenous Mental Health Worker Register.

INTRODUCTION: Inaccuracy in identification of Indigenous status on health records hampers collection of the good quality data required to guide policies, programs and services. This study examined the use of an Indigenous Mental Health Worker Register to assess the level of correct identification of Indigenous status and sources of error among psychiatric admissions within a regional public hospital information system. METHOD: The study was conducted in 2004/2005 and 2005/2006 at the Cairns Base Hospital Mental Health Unit, Queensland, Australia, serving a population of 230,000 of which 13.2% identify as Aboriginal and/or Torres Strait Islander. Psychiatric admissions data, including Indigenous status, accessed from the hospital-based corporate information system (HBCIS) were compared with data collected through an Indigenous Mental Health Worker Register that is maintained through extensive networking. Investigation of mismatches enabled estimation of the frequency and sources of incorrect identification of Indigenous status and the impact of this on hospital statistics. RESULTS: Cross-validation of HBCIS data with the Indigenous Register over 2 years revealed 355 Indigenous admissions. Of the total 355 admissions, 301 (84.8%) were correctly identified and included in the hospital system, while 22 (6.2%) were designated non-Indigenous, 13 (3.7%) were 'unspecified' and 19 (5.4%) were missed through incorrect residence or admission designation. Among 1293 non-Indigenous admissions, 1.1% were incorrectly identified as Indigenous, while 25.5% of the 51 with unspecified status were found to be Indigenous. Furthermore, 45 Indigenous separations that had been missed over the previous 5 year period (1999/2000 to 2003/2004) were identified through careful examination of all those with unspecified status (n=174) and those with multiple separations of mixed designation of Indigenous status (n=15); all of the latter 15 were confirmed Indigenous by other mental health database and/or the Indigenous Mental Health Worker. Thus overall this study revealed a total of 89 Indigenous separations and 1261 occupied bed days in the 7 year period that had not be identified in the hospital information system. CONCLUSION: A novel method was used to ascertain the reliability of Indigenous status identification among mental health admissions within a hospital information system in a region with relatively high Indigenous population representation. This revealed that 85% of admissions were correctly identified over two consecutive years. Perhaps more importantly, the study confirmed a low frequency of false identification of non-Indigenous people as Aboriginal and/or Torres Strait Islander. The work has also demonstrated the value of involving Indigenous Mental Health Workers in routine processes to enhance, validate and improve Indigenous statistics and increase access to culturally informed care.

Culture, history, and health in an Australian aboriginal community: the case of utopia.

The poor health of Indigenous Australians is well established. However, the health of residents of one remote community in the Northern Territory of Australia called Utopia has been found recently to be much better than expected. In this article, we draw on historical anthropological research to explain this finding. We trace how cultural and social structures were maintained through changing eras of government policy from the 1930s, and show how these structures strengthened psychosocial determinants of health. We argue that the mainstream psychosocial determinants of social cohesion and self-efficacy are usefully reconceptualized in an Indigenous context as connectedness to culture and land, and collective efficacy, respectively. Continuity of cultural and social structures into the 1940s was facilitated by a combination of factors including the relatively late colonial occupation, the intercultural practices typical of the pastoral industry, the absence of a mission or government settlement, and the individual personalities and histories of those connected to Utopia.

Mutational origin of Machado-Joseph disease in the Australian Aboriginal communities of Groote Eylandt and Yirrkala.

OBJECTIVE: To determine whether the presence of Machado-Joseph disease (MJD, also spinocerebellar ataxia type 3 [SCA3]) among Australian aborigines was caused by a new mutational event or by the introduction of expanded alleles from other populations. DESIGN: We sequenced a region of 4 kilobases (kb), encompassing the CAG repeat within the ATXN3 gene, in 2 affected Australian aboriginal families and compared them with the Joseph and Machado lineages described before. Full-extended haplotypes (including also more distant single-nucleotide polymorphisms and flanking short tandem repeats) were assessed by segregation and allele-specific amplification. A phylogenetic tree was inferred from genetic distances, and age of the Australasian Joseph-derived lineage was estimated. SETTING: The aboriginal communities of Groote Eylandt and Yirrkala, in the Northern Territories, Australia (local ethics institutional permission was granted, and both community and individual informed consent was obtained). SUBJECTS: A convenience sample of 19 patients and unaffected relatives, from 2 Australian aboriginal families affected with MJD; 40 families with MJD of multiethnic origins and 50 unrelated Asian control subjects. RESULTS: The 2 aboriginal families shared the same full haplotype, including 20 single-nucleotide polymorphisms:TTGATCGAGC-(CAG)(Exp)-CACCCAGCGC, that is, the Joseph lineage with a G variant in rs56268847.Among 33 families with the Joseph lineage, this derived haplotype was found only in 5 of 16 Taiwanese, all 3 Indian,and 1 of 3 Japanese families analyzed. CONCLUSION: A related-extended MJD haplotype shared by Australian aborigines and some Asian families (a Joseph-derived lineage) suggests a common ancestor for all, dating back more than 7000 years.

Performance of comorbidity indices in measuring outcomes after acute myocardial infarction in Australian indigenous and non-indigenous patients.

BACKGROUND: Indigenous Australians have higher prevalence of chronic diseases and worse acute care outcomes than other Australians. The extent to which higher chronic disease comorbidity levels are responsible for their worse outcomes is not clear, and the performance of comorbidity indices has not been assessed for this population with very high comorbidity levels. METHODS: Using hospital separations data, the Charlson and Elixhauser comorbidity indices were used to measure chronic disease prevalence in 2035 indigenous and non-indigenous patients hospitalised after their first acute myocardial infarction (AMI) in the Northern Territory of Australia between 1992 and 2004, and to adjust for comorbidity in multivariate analysis of mortality outcomes (in-hospital and long-term deaths from coronary heart disease and all causes). Index performance was assessed by the difference between C statistic, Akaike information criterion statistic and estimate of excess indigenous mortality in models with and without comorbidity adjustment. RESULTS: Comorbidity index scores were higher for indigenous than non-indigenous patients and increased considerably over time, at least partly because of information bias. Indigenous patients' higher risk of in-hospital all-cause death was almost fully explained by their higher comorbidity levels. Their higher risk of long-term coronary heart disease and all-cause death was partially explained by higher comorbidity levels. Charlson and Elixhauser indices performed satisfactorily and similarly in this population. CONCLUSION: Comorbidity indices performed well in a population with very high chronic disease prevalence. After adjusting for comorbidity, short-term outcomes were similar for indigenous and non-indigenous AMI patients, but comorbidity at the time of the acute episode only partly explained the worse long-term outcomes for indigenous patients.

Staphylococcus aureus bacteraemia at Alice Springs Hospital, Central Australia, 2003-2006.

BACKGROUND: Infectious diseases remain the leading cause of death at Alice Springs Hospital (ASH) and Staphylococcus aureus bacteraemia (SAB) is the second most common bloodstream infection. Non-multidrug-resistant, methicillin-resistant S. aureus (nmMRSA) is endemic to the region. AIMS: To determine whether differences exist between racial groups and resistance phenotypes in the clinical manifestations and outcomes of SAB at ASH. METHODS: A retrospective review of medical and pathology records for inpatients with SAB between 1 January 2003 and 31 December 2006. RESULTS: A total of 125 patients (indigenous, 111; non-indigenous, 14) presented with SAB during the study period. Among indigenous patients, there were 95 adults and 16 children. No non-indigenous child was admitted with SAB. The mean annual incidence rate was 160.7/100 000 indigenous population and 8.1/100 000 non-indigenous population (incidence rate ratio 19.9) (P = 0.010). Isolates were predominantly methicillin-susceptible S. aureus (indigenous, 85; non-indigenous, 13). Twenty of 27 MRSA isolates were non-multidrug-resistant. Indigenous adults were more likely to present with an infective focus (indigenous, 75; non-indigenous, 6) (P = 0.004). These were most often skin infections (skin abscesses, 31; scabies, 4). Twenty-seven indigenous adults self-discharged after receiving a median of only 5 days (inter-quartile range (IQR), 3-9) of antibiotic therapy. Ninety-day mortality rates for indigenous and non-indigenous adults were 14.7% and 14.3% respectively. The median age of death for indigenous adults was 50 years (IQR, 37-68). CONCLUSIONS: Indigenous Australians have the highest reported incidence rate of SAB worldwide. This reflects the socioeconomic disadvantage experienced by indigenous Australians whose living conditions predispose to pathogen transmission and limits opportunities to maintain adequate skin hygiene.

Can we measure daily tobacco consumption in remote indigenous communities? Comparing self-reported tobacco consumption with community-level estimates in an Arnhem Land study.

INTRODUCTION AND AIMS: In remote Indigenous Australian communities measuring individual tobacco use can be confounded by cultural expectations, including sharing. We compared self-reported tobacco consumption with community-level estimates in Arnhem Land (Northern Territory). DESIGN AND METHODS: In a cross-sectional survey in three communities (population 2319 Indigenous residents, aged ≥16 years), 400 Indigenous residents were interviewed (206 men, 194 women). Eight community stores provided information about tobacco sold during the survey. To gauge the impact of 255 non-Indigenous residents on tobacco turnover, 10 were interviewed (five men, five women). Breath carbon monoxide levels confirmed self-reported smoking. Self-reported number of cigarettes smoked per day was compared with daily tobacco consumption per user estimated using amounts of tobacco sold during 12 months before the survey (2007-2008). 'Lighter smokers' (<10 cigarettes per day) and 'heavier smokers' (≥10 cigarettes per day) in men and women were compared. RESULTS: Of 400 Indigenous study participants, 305 (76%) used tobacco; four chewed tobacco. Of 301 Indigenous smokers, 177 (58%) provided self-reported consumption information; a median of 11-11.5 cigarettes per day in men and 5.5-10 cigarettes per day in women. Men were three times (odds ratio=2.9) more likely to be 'heavier smokers'. Store turnover data indicated that Indigenous tobacco users consumed the equivalent of 9.2-13.1 cigarettes per day; very similar to self-reported levels. Sixty per cent (=6/10) of non-Indigenous residents interviewed were smokers, but with little impact on tobacco turnover overall (2-6%). DISCUSSION AND CONCLUSIONS: Smoking levels reported by Indigenous Australians in this study, when sharing tobacco was considered, closely reflected quantities of tobacco sold in community stores.

Screening for hepatitis B in East Arnhem Land: a high prevalence of chronic infection despite incomplete screening.

Infection with hepatitis B virus (HBV) is common in Aboriginal Australians, but current seroprevalences in Northern Territory communities are unknown. We performed an audit of HBV serology on a convenience sample of 112 adults at an East Arnhem Land Health Service. Complete HBV serology was only available in 26 (23%) patients. Evidence of HBV exposure (core antibody-positive) was found in 43 of 68 (63%) patients tested, and current HBV infection (surface antigen-positive) was found in nine of 76 (12%). HBV is an incompletely defined, under-resourced and substantial public health problem in Aboriginal Australians.