A retrospective, longitudinal cohort study of trends and risk factors for preterm birth in the Northern Territory, Australia.

BACKGROUND: Preterm birth (PTB) is the single most important cause of perinatal mortality and morbidity in high income countries. In Australia, 8.6% of babies are born preterm but substantial variability exists between States and Territories. Previous reports suggest PTB rates are highest in the Northern Territory (NT), but comprehensive analysis of trends and risk factors are lacking in this region. The objective of this study was to characterise temporal trends in PTB among First Nations and non-First Nations mothers in the Top End of the NT over a 10-year period and to identify perinatal factors associated with the risk of PTB. METHODS: This was a retrospective population-based cohort study of all births in the Top End of the NT over the 10-year period from January 1st, 2008, to December 31st, 2017. We described maternal characteristics, obstetric complications, birth characteristics and annual trends in PTB. The association between the characteristics and the risk of PTB was determined using univariate and multivariate generalised linear models producing crude risk ratios (cRR) and adjusted risk ratios (aRR). Data were analysed overall, in First Nations and non-First Nations women. RESULTS: During the decade ending in 2017, annual rates of PTB in the Top End of the NT remained consistently close to 10% of all live births. However, First Nations women experienced more than twice the risk of PTB (16%) compared to other women (7%). Leading risk factors for PTB among First Nations women as compared to other women included premature rupture of membranes (RR 12.33; 95% CI 11.78, 12.90), multiple pregnancy (RR 7.24; 95% CI 6.68, 7.83), antepartum haemorrhage (RR 4.36; 95% CI 3.93, 4.84) and pre-existing diabetes (RR 4.18; 95% CI 3.67, 4.76). CONCLUSIONS: First Nations women experience some of the highest PTB rates globally. Addressing specific pregnancy complications provides avenues for intervention, but the story is complex and deeper exploration is warranted. A holistic approach that also acknowledges the influence of socio-demographic influences, such as remote dwelling and disadvantage on disease burden, will be required to improve perinatal outcomes.

How Barunga Aboriginal community implemented and sustained an anaemia program - A case study evaluation.

ISSUE ADDRESSED: Anaemia persists as a public health issue in many Aboriginal communities despite having standard practice guidelines. This case study reveals how Barunga Aboriginal Community in the Northern Territory (NT), Australia, implemented an Anaemia Program (1998-2016) which contributed to low anaemia prevalence in children aged under 5 years. METHODS: This retrospective qualitative case study used purposive sampling to describe the Anaemia Program and factors influencing its implementation. Themes were developed from convergence of three data sources: interviews, program observation and document review. Data were inductively analysed by an Aboriginal and non-Aboriginal researcher and themes were validated by Barunga community health practitioners and compared to practice guidelines and implementation literature. RESULTS: Health practitioners reported that the Anaemia Program contributed to a marked reduction in childhood anaemia prevalence over time. This was supported by available prevalence data. The locally adapted Anaemia Program was unique in the NT with a novel approach to community supplementation for anaemia prevention in addition to anaemia treatment. Supportive implementation influences included: Aboriginal leadership and the use of culturally supportive processes which reinforced the development of trust and strong relationships facilitating community acceptance of the Program. Routine, opportunistic and flexible health care practice, a holistic approach and a stable, skilled and experienced team sustained program implementation. CONCLUSIONS: The holistic and successful Barunga Anaemia Program is supported by evidence and guidelines for treating and preventing childhood anaemia. The contextualisation of these guidelines aligned with the literature on effective Aboriginal primary health care implementation. SO WHAT?: This Anaemia Program provides a model for implementation of evidence-informed guidelines in an Aboriginal primary health care setting.

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 incidence and outcome of clinically significant antibodies detected in Rhesus-D positive pregnant women of the Northern Territory.

BACKGROUND: Haemolytic disease of the fetus/newborn secondary to clinically significant non-Rhesus-D antibodies has risen in importance since the advent of immunoprophylactic anti-D administration to Rhesus-D negative women. Of interest is the incidence of these antibodies in Rhesus-D positive women, who receive less frequent antenatal alloantibody screening. This is of particular concern if the antibodies arise late in pregnancy and may go undetected. AIMS: To assess the proportion of Rhesus-D positive pregnant women with late developing clinically significant antibodies for haemolytic disease of the fetus/newborn, and whether these resulted in adverse fetal outcomes. MATERIALS AND METHODS: A retrospective analysis over a 12-month period at a tertiary hospital in the Northern Territory. Group and antibody screen results in addition to clinical data regarding pregnancy/newborn were collected. RESULTS: Sixty-four of 2612 women (2.5%) had red blood cell antibodies detected during their pregnancy. Of these, 21 clinically significant antibodies were detected in 19 women (0.7% of initial cohort). The most common antibody detected was anti-c (28.5%). In six of these women (0.23% of initial cohort), the antibodies were late developing. Mild jaundice was noted in three newborns with phototherapy required in one. CONCLUSIONS: Although clinically significant antibodies were detected during pregnancy, and in a small proportion of cases as a late developing antibody undetected in the first trimester screening, clinical outcomes for the newborn were mild. As such, the cost of retesting all Rhesus-D positive pregnant women in the third trimester would be considerable and unlikely to result in any meaningful clinical benefit.

Molecular Antimicrobial Resistance Surveillance for Neisseria gonorrhoeae, Northern Territory, Australia.

Neisseria gonorrhoeae antimicrobial resistance (AMR) is a globally recognized health threat; new strategies are needed to enhance AMR surveillance. The Northern Territory of Australia is unique in that 2 different first-line therapies, based primarily on geographic location, are used for gonorrhea treatment. We tested 1,629 N. gonorrhoeae nucleic acid amplification test-positive clinical samples, collected from regions where ceftriaxone plus azithromycin or amoxicillin plus azithromycin are recommended first-line treatments, by using 8 N. gonorrhoeae AMR PCR assays. We compared results with those from routine culture-based surveillance data. PCR data confirmed an absence of ceftriaxone resistance and a low level of azithromycin resistance (0.2%), and that penicillin resistance was <5% in amoxicillin plus azithromycin regions. Rates of ciprofloxacin resistance and penicillinase-producing N. gonorrhoeae were lower when molecular methods were used. Molecular methods to detect N. gonorrhoeae AMR can increase the evidence base for treatment guidelines, particularly in settings where culture-based surveillance is limited.

Multidrug-resistant tuberculosis in the Northern Territory: A 10-year retrospective case series.

BACKGROUND AND OBJECTIVE: To describe the clinical characteristics, risk factors, diagnostic modalities, treatments, subsequent outcomes and complications of Multidrug-resistant tuberculosis (MDR-TB) cases residing in the Northern Territory. METHODS: A retrospective case series was conducted of all patients treated for MDR-TB in the Northern Territory between 1 January 2004 and 31 December 2013. This is the first study to analyse data relating to the subset of MDR-TB cases treated in the Northern Territory. Cases were identified by the Northern Territory Centre for Disease Control (NT CDC): the public health unit responsible for the management of tuberculosis in the Northern Territory. Outcome measures included patient demographics, diagnostics, HIV status, treatment methods, outcomes, and complications. RESULTS AND CONCLUSIONS: Six MDR-TB cases were treated in the Northern Territory; 5 of these were notified by the NT CDC during the study period (1.5% of all Northern Territory TB notifications). The median age of all 6 patients was 31 years (range 21 to 50 years), sex distribution was equal and all were born overseas. Country of birth in a World Health Organization (WHO) high burden MDR-TB country and previous treatment were most highly correlated with a current diagnosis of MDR-TB. Access to rapid drug susceptibility testing reduced the time to effective therapy from 45 to 27 days. Five patients met criteria for the WHO outcome term 'treatment success'. The median length of treatment for the 5 patients treated in Australia was 623 days (537 to 730 days). Side effects to therapy were common and serious. The incidence of MDR-TB in the Northern Territory is similar to other Australian states. Rapid drug susceptibility testing reduces the time to effective therapy. Treatment regimens are complex, toxic and have serious resource implications for health care providers. Successful treatment outcomes are possible with coordinated TB control programs. Commun Dis Intell 2016;40(3):E334-E339.

A cost-consequences analysis of a midwifery group practice for Aboriginal mothers and infants in the top end of the Northern Territory, Australia.

OBJECTIVE: to compare the cost-effectiveness of two models of service delivery: Midwifery Group Practice (MGP) and baseline cohort. DESIGN: a retrospective and prospective cohort study. SETTING: a regional hospital in Northern Territory (NT), Australia. METHODS: baseline cohort included all Aboriginal mothers (n=412), and their infants (n=416), from two remote communities who gave birth between 2004 and 2006. The MGP cohort included all Aboriginal mothers (n=310), and their infants (n=315), from seven communities who gave birth between 2009 and 2011. The baseline cohort mothers and infant's medical records were retrospectively audited and the MGP cohort data were prospectively collected. All the direct costs, from the Department of Health (DH) perspective, occurred from the first antenatal presentation to six weeks post partum for mothers and up to 28 days post births for infants were included for analysis. ANALYSIS: analysis was performed with SPSS 19.0 and Stata 12.1. Independent sample of t-tests and χ2 were conducted. FINDINGS: women receiving MGP care had significantly more antenatal care, more ultrasounds, were more likely to be admitted to hospital antenatally, and had more postnatal care in town. The MGP cohort had significantly reduced average length of stay for infants admitted to Special Care Nursery (SCN). There was no significant difference between the two cohorts for major birth outcomes such as mode of birth, preterm birth rate and low birth weight. Costs savings (mean A$703) were found, although these were not statistically significant, for women and their infants receiving MGP care compared to the baseline cohort. CONCLUSIONS: for remote dwelling Aboriginal women of all risk who travelled to town for birth, MGP was likely to be cost effective, and women received better care and resulting in equivalent birth outcomes compared with the baseline maternity care.

Iodine status of Aboriginal teenagers in the Darwin region before mandatory iodine fortification of bread.

OBJECTIVE: To determine the iodine status of participants in the Aboriginal Birth Cohort Study who resided in the Darwin Health Region (DHR) in the "Top End" of the Northern Territory prior to the introduction of mandatory iodine fortification of bread. DESIGN, SETTING AND PARTICIPANTS: Participants in our study had been recruited at birth and were followed up at a mean age of 17.8 years. Spot urine samples were collected and assessed for iodine concentration at a reference laboratory. The median urinary iodine concentration (MUIC) of residents of the DHR was calculated and compared with international criteria for iodine status. Analyses were conducted for subgroups living in urban areas (Darwin-Palmerston) and remote communities (rural with an Aboriginal council). We collected a repeat sample in a subset of participants to explore the impact of within-person variation on the results. MAIN OUTCOME MEASURE: MUIC for residents of the DHR. RESULTS: Urine specimens were provided by 376 participants in the DHR. Overall MUIC was 58 µg/L when weighted to the 2006 Census population. Urban boys had higher values (MUIC = 77 µg/L) than urban and remote-dwelling non-pregnant girls (MUIC = 55 µg/L), but all these groups were classified as mildly iodine deficient. Remote-dwelling boys had the lowest MUIC (47 µg/L, moderate deficiency). Pregnant girls and those with infants aged less than 6 months also had insufficient iodine status. Correction for within-person variation reduced the spread of the population distribution. CONCLUSIONS: Previously, iodine deficiency was thought to occur only in the south-eastern states of Australia. This is the first report of iodine deficiency occurring in residents of the NT. It is also the first study of iodine status in a defined Indigenous population. Future follow-up will reassess iodine status in this group after the introduction of iodine fortification of bread.

Substance use and periodontal disease among Australian Aboriginal young adults.

AIM: To investigate the effects of tobacco, marijuana, alcohol and petrol sniffing on periodontal disease among Australian Aboriginal young adults. DESIGN: Cross-sectional nested within a long-standing prospective longitudinal study. Setting Aboriginal communities in Australia's Northern Territory. PARTICIPANTS: Members of the Aboriginal Birth Cohort study who were recruited from birth between January 1987 and March 1990 at the Royal Darwin Hospital, Northern Territory, Australia. Data were from wave III, when the mean age of participants was 18 years. MEASUREMENTS: Clinical dental examination and self-report questionnaire. FINDINGS: Of 425 participants with complete data, 26.6% had moderate/severe periodontal disease. There was elevated risk of periodontal disease associated with tobacco [prevalence ratio (PR) = 1.59, 95% CI = 1.06-2.40], marijuana (PR = 1.44, 95% CI = 1.05-1.97) and petrol sniffing (PR = 1.83, 95% CI = 1.08-3.11), but not alcohol (PR = 0.92, 95% CI = 0.67-1.27). Stratified analysis showed that the effect of marijuana persisted among tobacco users (PR = 1.47, 95% CI 1.03-2.11). It was not possible to isolate an independent effect of petrol sniffing because all petrol sniffers used both marijuana and tobacco, although among smokers of both substances, petrol sniffing was associated with an 11.8% increased prevalence of periodontal disease. CONCLUSIONS: This is the first time that substance use has been linked with periodontal disease in a young Australian Aboriginal adult population, and the first time that petrol sniffing has been linked with periodontal disease in any population. The role of substance use in periodontal disease among this, and other, marginalized groups warrants further investigation.

Pollen loads and allergic rhinitis in Darwin, Australia: a potential health outcome of the grass-fire cycle.

Although the prevalence of asthma and allergic rhinitis has been increasing in tropical regions, little is known about the allergenicity of pollens from tropical plant families or the importance of ongoing environmental changes. We investigated associations between daily average pollen counts of several tropical plant families and sales of medications for the treatment of allergic rhinitis in Darwin, Australia-a tropical setting in which grass abundance has increased due to increased fire frequencies and the introduction of African pasture grasses. Daily pollen counts with detailed identification of plant species were undertaken in conjunction with a weekly survey of flowering plant species from April 2004 to November 2005. Five pharmacies provided daily sales data of selected medications commonly used to treat allergic rhinitis. We used generalized linear modeling to examine outcomes. All analyses accounted for the potential confounding effects of time trends, holidays, respiratory viral illnesses, meteorological conditions, and air pollution. The peak total pollen count was 94 grains/m(3). Despite the low levels of Poaceae (grass) pollen (maximum daily count, 24 grains/m(3)), there was a clear association with daily sales of anti-allergic medications greatest at a lag of 1 day. Sales increased by 5% with an interquartile range rise (3 grain/m(3)) in Poaceae pollen (5.07%, 95%CI 1.04%, 9.25%). No associations were observed with pollen from other plant families. Although further testing is required, we suggest that an overlooked aspect of the "grass-fire cycle" that is degrading many tropical landscapes, could be an increase in the prevalence of allergic rhinitis.

Irukandji syndrome case series from Australia's Tropical Northern Territory.

STUDY OBJECTIVE: We describe Irukandji syndrome (a painful hypercatecholaminergic condition caused by jellyfish envenoming) in Australia's Northern Territory. METHODS: We collected prospectively a standardized data set on patients presenting to health facilities in the Northern Territory. Additional cases were identified retrospectively. Data collected included demographic, geographic, seasonal, and environmental features, as well as sting details, clinical manifestations, investigations, management, and outcomes. RESULTS: From 1990 to 2007, Irukandji syndrome affected 87 people. Age ranged from 1 to 51 years (64% male victims; 41% children [63% indigenous]). Activities associated with stings included snorkeling or scuba diving (35%) and swimming (29%). Stings commonly occurred in water greater than 2 m deep (63%), with fine weather (73%) and still or light breeze (70%). Seasonal variation was bimodal; peaks in May and October corresponded to prevailing offshore winds in the Darwin and Gove areas, respectively. Pain was severe (65%), with rapid onset (<30 minutes in 79%). Sting lesions (visible in 63%) were mild, and nematocysts (detected in 7 cases) had variable morphology. Systemic features were common, including hypertension and ECG abnormalities. Severe complications included troponin-level increases (2 cases) and cardiomyopathy with ventricular tachycardia (1 case), but no fatalities. Management included vinegar as first aid (66%), parenteral opioids (70%) (range 2 to 82.5 mg morphine equivalents in adults), and magnesium sulfate (3 cases). Hospital admission (49%) and aeromedical retrieval (16%) were commonplace. CONCLUSION: Irukandji syndrome in the Northern Territory was clinically consistent with previous studies but had distinct seasonal, geographic, and environmental features. Indigenous children in remote coastal communities are at risk, and there is room for improvement in prevention and management.

Immunisation coverage in Australian Indigenous children: Time to move the goal posts.

Childhood immunisation coverage reported at 12 to <15 months and 2 years of age, may mask deficiencies in the timeliness of vaccines designed to protect against diseases in infancy. This study aimed to evaluate immunisation timeliness in Indigenous infants in the Northern Territory, Australia. Coverage was analysed at the date children turned 7, 13 and 18 months of age. By 7 months of age, 45.2% of children had completed the recommended schedule, increasing to 49.5% and 81.2% at 13 and 18 months of age, respectively. Immunisation performance benchmarks must focus on improving the timeliness in these children in the first year of life.

Establishment of a surveillance system (utilising Midwifes Data Collection Systems) for monitoring the impact of hepatitis B vaccination on the population prevalence of chronic hepatitis B virus infection in Australia.

OBJECTIVE: To examine how routine hepatitis B surface antigen (HBsAg) testing of antenatal women (as identified on the NT Midwifes Data Collection System) can be used to track the impact of hepatitis B (HBV) vaccination on the prevalence of chronic HBV infection in the Northern Territory (NT). METHODS: Women who gave birth between 01 July 2002 and 30 June 2004 were identified from the NT Midwives Data Collection System (MDCS). For each woman, the unique hospital record number (HRN) was linked to the information system of the NT Government pathology service to obtain the results of serological tests for hepatitis B. The prevalence of HBsAg was calculated by age, Indigenous status, and maternal country of birth. RESULTS: During the study period, 1061 records of women from the NT MDCS could be linked to HBsAg results. Overall, 33 (3.1%) were positive for HBsAg, of whom 29 were recorded as Indigenous and the remaining four were born outside Australia. CONCLUSIONS: Linking data from the NT MDCS and HBsAg results from government pathology service is a feasible means to monitor the impact of HBV vaccination policy. IMPLICATIONS: Routine inclusion of HBsAg results in all state and territory midwives data collections should be pursued.

Participation in cervical screening by Indigenous women in the Northern Territory: a longitudinal study.

OBJECTIVE: To investigate the effectiveness of the Northern Territory Women's Cancer Prevention Program in improving cervical screening participation for Indigenous women. DESIGN: Descriptive longitudinal period prevalence study. PARTICIPANTS: All NT resident women aged 20-69 years who had at least one Pap smear recorded on the NT Pap Smear Register between 1997 and 2004. MAIN OUTCOME MEASURES: Indirectly estimated percentage of NT Indigenous women in rural and remote areas with a predominantly Indigenous population (accounting for 55% of the NT Indigenous population) who participated in screening, in biennial periods between 1997 and 2004. Participation by all eligible NT women (both Indigenous and non-Indigenous) is also reported by region for the same period. RESULTS: In 1997-1998, estimated participation for Indigenous women was about half the national rate (33.9% [95% CI, 32.6%-35.2%] v 63.9% [95% CI, 63.8%-63.9%]). Participation increased to 44.0% (95% CI, 42.7%-45.4%) in 1999-2000, and changed little thereafter; participation was higher in the Top End compared with Central Australia, and varied from 16.6% to 75.0% between remote areas. Participation rates for all women living in rural/remote regions were lower than those in urban regions. CONCLUSIONS: Recruitment of Indigenous women for cervical screening has improved since 1999. This may have partly contributed to the fall in their cervical cancer incidence and mortality in recent years. Although in most areas Indigenous participation is lower than national levels, in one area it was considerably higher. Improvements can be achieved by learning from these communities, to further close the gap in morbidity and mortality between Indigenous and non-Indigenous women.

Oral health inequalities among indigenous and nonindigenous children in the Northern Territory of Australia.

OBJECTIVE: To describe oral health inequalities among indigenous and nonindigenous children in the Northern Territory of Australia using an area-based measure of socioeconomic status (SES). METHODS: Data were obtained from indigenous and nonindigenous 4-13-year-old children enrolled in the Northern Territory School Dental Service in 2002-2003. The Socio-Economic Indices For Areas (SEIFA) were used to determine socioeconomic relationships with dental disease experience. RESULTS: Some 12,584 children were examined, 35.1% of whom were indigenous. Across all age-groups, socially disadvantaged indigenous children experienced higher mean dmft and DMFT levels than their similarly aged, similarly disadvantaged nonindigenous counterparts. Indigenous children aged 5 years had almost four times the dmft of their nonindigenous counterparts in the same disadvantage category (P < 0.05), while indigenous children aged 10 years had almost five times the DMFT of similarly disadvantaged nonindigenous children (P < 0.05). A distinct social gradient was apparent among indigenous and nonindigenous children, respectively, whereby those with the highest dmft/DMFT levels were in the most disadvantaged SES category and those least disadvantaged had the lowest dmft/DMFT levels. In most age-groups, indigenous children who were least disadvantaged had worse oral health than the most disadvantaged nonindigenous children. CONCLUSIONS: The findings suggest that indigenous status and SES have strong oral health outcome correlations but are not mutually dependent, that is, indigenous status influences oral health outcomes irrespective of social disadvantage. From a health policy perspective, greater oral health gains may be possible by concentrating public health and clinical effort among all indigenous children irrespective of SES status.

Intussusception in the Northern Territory: the incidence is low in Aboriginal and Torres Strait Islander children.

AIM: To describe the epidemiology, immunisation status and management of children with intussusception in the Northern Territory (NT), 1993-2003. METHODS: Intussusception data were obtained from all NT hospitals using the International Classification of Diseases (ICD 9/10) codes for children under 18 years of age between 1993 and 2003. Medical records of these children were used to collect information on demographics, admission date, clinical symptoms, signs and management. Immunisation data were obtained from the NT immunisation register. The NT mortality database was reviewed for deaths from intussusception in children between 1993 and 2003. One death in an Aboriginal and Torres Strait Islander child was found in the NT mortality database. Medical records for this child were destroyed and so the case definition for intussusception used in this study was not fulfilled and the child was excluded. RESULTS: Intussusception proven by radiological or surgical means was identified in 23 children from hospital records. The incidence for children with intussusception in NT is 0.65/1000 live births. The incidence of intussusception was lower in Aboriginal and Torres Strait Islander children (0.16/1000 live births) than in non-Aboriginal and Torres Strait Islander children (0.92/1000 live births) (P < 0.01). CONCLUSION: The incidence of intussusception in the NT is similar to other developed countries but Aboriginal and Torres Strait Islander children have a very low incidence of intussusception. Intussusception is a rare event in the NT and will require a sensitive surveillance system to detect any potential increased risk of intussusception after the introduction of a new rotavirus vaccine.