Australian First Nations response to the pandemic: A dramatic reversal of the 'gap'.

Until the recent death in Dubbo of an Aboriginal man, there have been no deaths from Covid 19 in Australia. The extraordinary success of Aboriginal and Torres Strait Islander populations in controlling the effects of this pandemic has been a global role model. Until early 2021, in spite of their high risk status, dispersed population and fear of health services due to racism, Indigenous outcomes were better than those for non-Indigenous. Aboriginal health leaders at every level brought in worlds best practices and applied them in all urban, rural and remote locations. Instead of the many hundreds of cases, hospitalisation and deaths expected, there were only 150 cases nationwide with15% hospitalised but no one in ICU and no deaths. This result is a complete reversal of the gap and was due to the outstanding Indigenous leadership, that governments at all levels listened to Aboriginal wisdom and that control was handed to those who knew what to do. This result is not only evidence for why a Voice enshrined in the Constitution would work, it heralds a new way of working with Aboriginal people in Australia. This viewpoint makes the case for a different model to engage and empower First Nations to really close the gap - themselves.

A Population-Based Matched-Sibling Analysis Estimating the Associations Between First Interpregnancy Interval and Birth Outcomes.

The association between a single interpregnancy interval (IPI) and birth outcomes has not yet been explored using matched methods. We modeled the odds of preterm birth, being small for gestational age, and having low birth weight in a second, live-born infant in a cohort of 192,041 sibling pairs born in Western Australia between 1980 and 2010. The association between IPI and birth outcomes was estimated from the interaction between birth order and IPI (with 18-23 months as the reference category), using conditional logistic regression. Matched analysis showed the odds of preterm birth were higher for siblings born following an IPI of <6 months (adjusted interaction odds ratio = 1.22, 95% confidence interval: 1.06, 1.38) compared with those born after an IPI of 18-23 months. There were no significant differences for IPIs of <6 months for other outcomes (small for gestational age or low birth weight). This is the first study to use matched analyses to investigate the association between a single IPI on birth outcomes. IPIs of <6 months were associated with increased odds of preterm birth in second-born infants, although the association is likely smaller than previously estimated by unmatched studies.

Predicting Long-Term Survival Without Major Disability for Infants Born Preterm.

OBJECTIVE: To describe the long-term neurodevelopmental and cognitive outcomes for children born preterm. STUDY DESIGN: In this retrospective cohort study, information on children born in Western Australia between 1983 and 2010 was obtained through linkage to population databases on births, deaths, and disabilities. For the purpose of this study, disability was defined as a diagnosis of intellectual disability, autism, or cerebral palsy. The Kaplan-Meier method was used to estimate the probability of disability-free survival up to age 25 years by gestational age. The effect of covariates and predicted survival was examined using parametric survival models. RESULTS: Of the 720 901 recorded live births, 12 083 children were diagnosed with disability, and 5662 died without any disability diagnosis. The estimated probability of disability-free survival to 25 years was 4.1% for those born at gestational age 22 weeks, 19.7% for those born at 23 weeks, 42.4% for those born at 24 weeks, 53.0% for those born at 25 weeks, 78.3% for those born at 28 weeks, and 97.2% for those born full term (39-41 weeks). There was substantial disparity in the predicted probability of disability-free survival for children born at all gestational ages by birth profile, with 5-year estimates of 4.9% and 10.4% among Aboriginal and Caucasian populations, respectively, born at 24-27 weeks and considered at high risk (based on low Apgar score, male sex, low sociodemographic status, and remote region of residence) and 91.2% and 93.3%, respectively, for those at low risk (ie, high Apgar score, female sex, high sociodemographic status, residence in a major city). CONCLUSIONS: Apgar score, birth weight, sex, socioeconomic status, and maternal ethnicity, in addition to gestational age, have pronounced impacts on disability-free survival.

Disparities between Aboriginal and non-Aboriginal perinatal mortality rates in Western Australia from 1980 to 2015.

BACKGROUND: Perinatal mortality rates are typically higher in Aboriginal than non-Aboriginal populations of Australia. OBJECTIVES: This study aimed to examine the pattern of stillbirth and neonatal mortality rate disparities over time in Western Australia, including an evaluation of these disparities across gestational age groupings. METHODS: All singleton births (≥20 weeks gestation) in Western Australia between 1980 and 2015 were included. Linked data were obtained from core population health datasets of Western Australia. Stillbirth and neonatal mortality rates and percentage changes in the rates over time were calculated by Aboriginal status and gestational age categories. RESULTS: From 1980 to 2015, data were available for 930 926 births (925 715 livebirths, 5211 stillbirths and 2476 neonatal deaths). Over the study period, there was a substantial reduction in both the Aboriginal (19.6%) and non-Aboriginal (32.3%) stillbirth rates. These reductions were evident in most gestational age categories among non-Aboriginal births and in Aboriginal term births. Concomitantly, neonatal mortality rates decreased in all gestational age windows for both populations, ranging from 32.1% to 77.5%. The overall stillbirth and neonatal mortality rate differences between Aboriginal and non-Aboriginal birth decreased by 0.6 per 1000 births and 3.9 per 1000 livebirths, respectively, although the rate ratios (RR 2.51, 95% CI 2.14, 2.94) and (RR 2.94, 95% CI 2.24, 3.85), respectively reflect a persistent excess of Aboriginal perinatal mortality across the study period. CONCLUSIONS: Despite steady improvements in perinatal mortality rates in Western Australia over 3½ decades, the gap between Aboriginal and non-Aboriginal rates remains unchanged in relative terms. There is a continuing, pressing need to address modifiable risk factors for preventable early mortality in Aboriginal populations.

A large proportion of poor birth outcomes among Aboriginal Western Australians are attributable to smoking, alcohol and substance misuse, and assault.

BACKGROUND: Aboriginal infants have poorer birth outcomes than non-Aboriginal infants. Harmful use of tobacco, alcohol, and other substances is higher among Aboriginal women, as is violence, due to factors such as intergenerational trauma and poverty. We estimated the proportion of small for gestational age (SGA) births, preterm births, and perinatal deaths that could be attributed to these risks. METHODS: Birth, hospital, mental health, and death records for Aboriginal singleton infants born in Western Australia from 1998 to 2010 and their parents were linked. Using logistic regression with a generalized estimating equation approach, associations with birth outcomes and population attributable fractions were estimated after adjusting for demographic factors and maternal health during pregnancy. RESULTS: Of 28,119 births, 16% of infants were SGA, 13% were preterm, and 2% died perinatally. 51% of infants were exposed in utero to at least one of the risk factors and the fractions attributable to them were 37% (SGA), 16% (preterm) and 20% (perinatal death). CONCLUSIONS: A large proportion of adverse outcomes were attributable to the modifiable risk factors of substance use and assault. Significant improvements in Aboriginal perinatal health are likely to follow reductions in these risk factors. These results highlight the importance of identifying and implementing risk reduction measures which are effective in, and supported by, Aboriginal women, families, and communities.

Stillbirth and neonatal death rates across time: the influence of pregnancy terminations and birth defects in a Western Australian population-based cohort study.

BACKGROUND: The stillbirth rate in most high income countries reduced in the early part of the 20(th) century but has apparently been static over the past 2½ decades. However, there has not been any account taken of pregnancy terminations and birth defects on these trends. The current study sought to quantify these relationships using linked Western Australian administrative data for the years 1986-2010. METHODS: We analysed a retrospective, population-based cohort of Western Australia births from 1986 to 2010, with de-identified linked data from core population health datasets. RESULTS: The study revealed a significant decrease in the neonatal death rate from 1986 to 2010 (6.1 to 2.1 neonatal deaths per 1000 births; p < .01), while the overall stillbirth rate remained static. The stillbirth trend was driven by deaths in the extremely preterm period (20-27 weeks; which account for about half of all recorded stillbirths and neonatal deaths), masking significant decreases in the rate of stillbirth at very preterm (28-31 weeks), moderate to late preterm (32-36 weeks), and term (37+ weeks). For singletons, birth defects made up an increasing proportion of stillbirths and decreasing proportion of neonatal deaths over the study period-a shift that appears to have been largely driven by the increase in late pregnancy terminations (20 weeks or more gestation). After accounting for pregnancy terminations, we observed a significant downward trend in stillbirth and neonatal death rates at every gestational age. CONCLUSIONS: Changes in clinical practice related to pregnancy terminations have played a substantial role in shaping stillbirth and neonatal death rates in Western Australia over the 2½ decades to 2010. The study underscores the need to disaggregate perinatal mortality data in order to support a fuller consideration of the influence of pregnancy terminations and birth defects when assessing change over time in the rates of stillbirth and neonatal death.

Trends in maternal and newborn health characteristics and obstetric interventions among Aboriginal and Torres Strait Islander mothers in Western Australia from 1986 to 2009.

BACKGROUND: Detailed analyses of long-term trends in Aboriginal maternal and newborn health characteristics are lacking. AIM: To examine trends in maternal and newborn health characteristics for all mothers who were recorded as Aboriginal in the Western Australian Midwives' Notification System from 1986 to 2009. MATERIALS AND METHODS: Births were categorised into four-year time intervals (1986-1989, 1990-1993, 1994-1997, 1998-2001, 2002-2005, 2006-2009). Trends in maternal demographic characteristics, pre-existing medical conditions, pregnancy complications and neonatal characteristics were examined. RESULTS: For 37 424 births recorded from 1986 to 2009, the proportion of births to mothers aged ≤19 years decreased (31-22%, P < 0.001) along with the prevalence of pre-eclampsia (6.8-4.0%, P < 0.001) and antepartum haemorrhage (4.8-3.2%, P < 0.001). There were increases in the prevalence of diabetes in pregnancy (3.8-6.6%, P < 0.001), induction of labour (17.8-21.4%, P < 0.001), elective caesarean (6.6-8.2%, P < 0.001) and emergency caesarean (9.5-14.9%, P < 0.001) deliveries. There were no changes in the overall prevalence of preterm births (15.4-15.9%, P = 0.32). However, increases were observed in the prevalence of medically indicated preterm births with and without prelabour rupture of membranes (1.0-1.7%; P < 0.001 and 3.3-4.3%; P = 0.005, respectively). There were no significant changes in the rates of smoking during pregnancy (51-52% from 1998 to 2009, P = 0.18), small-for-gestational age (16.9-17.2%, P = 0.07), suboptimal-birthweight (20.4-20.1%, P = 0.92), stillbirths (14.7 per 1000-12.1 per 1000, P = 0.22) and neonatal deaths (6.2 per 1000-5.5 per 1000, P = 0.68). CONCLUSION: Encouraging trends include reduced rates of teenage pregnancy, pre-eclampsia and antepartum haemorrhage. The persistent high rates of smoking during pregnancy, preterm births, stillbirths, neonatal deaths and increasing rates of diabetes in pregnancy are of concern.

Changes in Caesarean Delivery Rates in Western Australia from 1995 to 2010 by Gestational Age at Birth.

BACKGROUND: The caesarean delivery rate in the developed world has been increasing. It is not well understood how caesarean delivery rates have changed by gestational age at birth in Western Australia, particularly in relation to the introduction of the early-term delivery guidelines in Australia in 2006. METHODS: Data from the Western Australian Midwives Notification System were used to identify 193,136 singletons born to primiparous women at 34-42 weeks' gestation during 1995-2010. Caesarean delivery rates were calculated by gestational age group (34-36 weeks, 37-38 weeks, and 39-42 weeks) and stratified into pre-labour and in-labour caesarean delivery. The average annual percent change (AAPC) for the caesarean delivery rates was calculated using joinpoint regression. Log-binomial regression was used to estimate the risk of having a caesarean delivery while adjusting for maternal and antenatal factors. RESULTS: Caesarean delivery rates rose steadily from 1995 to 2005 (AAPC = 5.9%, [95% confidence interval (CI) 4.9, 6.9]), but stabilised since then (AAPC = 0.9%, [95% CI -1.9, 3.8]). The rate of in-labour caesarean deliveries rose consistently from 1995 to 2010 across all gestational age groups. The pre-labour caesarean delivery rate rise was most dominant at 37-38 weeks' gestation from 1995 to 2005 (AAPC = 6.8%, [95% CI 5.4, 8.2]), but declined during 2006-10 (AAPC = -4.5, [95% CI -6.7, -2.3]), while at the same time the rate at 39-42 weeks rose slightly. CONCLUSIONS: The rise in pre-labour caesarean deliveries during 1995-2005 occurred predominantly at 37-38 weeks' gestation, but declined again from 2006 to 2010. This suggests that the recently developed Australian early-term delivery guidelines may have had some success in reducing early-term deliveries in Western Australia.

Children diagnosed with attention deficit disorder and their hospitalisations: population data linkage study.

Examine the hospital admission risk in young children who are subsequently diagnosed with attention deficit hyperactivity disorder (ADHD). We conducted a population-based, record linkage study. Records of all non-Aboriginal children under 18 years who met the DSMIV/ICD10 criteria for ADHD and prescribed stimulant medication in Western Australia between 2003 and 2007 (n = 11,902) were linked to two other health data systems-the hospital morbidity data system and the midwives notification system (MNS). The non-ADHD reference population (n = 27,304) was randomly selected from the MNS. Compared with controls, children under 4 years who subsequently were diagnosed and treated for ADHD were 70% [odds ratio (OR) 1.70; 95% confidence intervals (CI) 1.62-1.77] more likely to be admitted to hospital under 4 years of age. There was an increased risk for injury or poison (OR 1.73; 95% CI 1.59-1.88), respiratory disease (OR 1.49; 95% CI 1.40-1.59), ear disease (OR 2.03; 95% CI 1.86-2.21), infectious diseases (OR 1.68; 95% CI 1.53-1.85) and neurological conditions (OR 2.03; 95% CI 1.68-2.44). Admissions under 4 years of age for head injuries, burns, poisons, all other injuries, diseases of the tonsils and adenoids, asthma and early infections were all more common amongst children subsequently diagnosed with and treated for ADHD. There is significant early hospital morbidity for children subsequently diagnosed with ADHD. Multiple aetiologies and causal pathways need to be considered where some of these may include early infections, inflammatory conditions, epilepsy and injuries. Future studies should look at which of these conditions may be on the causal pathway or likely early markers for ADHD.

Trends in pre-existing mental health disorders among parents of infants born in Western Australia from 1990 to 2005.

OBJECTIVE: To determine the prevalence of prior and current mental health disorders in parents, including trends over time. DESIGN: retrospective population cohort study using de-identified linked health data. SETTING: Population of Western Australia. SUBJECTS: All parents of infants born in WA between 1990 and 2005. MAIN OUTCOME MEASURES: Prevalence of prior mental health disorders in parents by birth 2013 and by parent and child characteristics, including Aboriginality, maternal age, socioeconomic status and diagnostic groups. RESULTS: From 1990 to 2005, there was an increase in prevalence of prior mental health disorders in mothers, from 76 per 1000 births in 1990 to 131 per 1000 births in 2005 (3.7% increase per 2013 in the odds of children being born to mothers with a prior mental health disorder). There was also a 4.7% increase in odds per 2013 in the prevalence of mental health contacts that had taken place in the 12 months before the birth 2013 in mothers. In addition, there was an increase in prevalence of prior mental health disorders in fathers, from 56 per 1000 births in 1990 to 88 per 1000 births in 2005 (3.1% increase in odds per 2013). The diagnostic group with the highest prevalence in both mothers and fathers was substance-related disorders. CONCLUSIONS: From 1990 to 2005, there was an increase in prevalence of parents with a prior history of mental health disorders in WA. General practitioners and mental health workers can play an important role in identifying mental illness and in working with families to offer early intervention, referral and support.

Are women with major depression in pregnancy identifiable in population health data?

BACKGROUND: Although record linkage of routinely collected health datasets is a valuable research resource, most datasets are established for administrative purposes and not for health outcomes research. In order for meaningful results to be extrapolated to specific populations, the limitations of the data and linkage methodology need to be investigated and clarified. It is the objective of this study to investigate the differences in ascertainment which may arise between a hospital admission dataset and a dispensing claims dataset, using major depression in pregnancy as an example. The safe use of antidepressants in pregnancy is an ongoing issue for clinicians with around 10% of pregnant women suffer from depression. As the birth admission will be the first admission to hospital during their pregnancy for most women, their use of antidepressants, or their depressive condition, may not be revealed to the attending hospital clinicians. This may result in adverse outcomes for the mother and infant. METHODS: Population-based de-identified data were provided from the Western Australian Data Linkage System linking the administrative health records of women with a delivery to related records from the Midwives' Notification System, the Hospital Morbidity Data System and the national Pharmaceutical Benefits Scheme dataset. The women with depression during their pregnancy were ascertained in two ways: women with dispensing records relating to dispensed antidepressant medicines with an WHO ATC code to the 3rd level, pharmacological subgroup, 'N06A Antidepressants'; and, women with any hospital admission during pregnancy, including the birth admission, if a comorbidity was recorded relating to depression. RESULTS: From 2002 to 2005, there were 96698 births in WA. At least one antidepressant was dispensed to 4485 (4.6%) pregnant women. There were 3010 (3.1%) women with a comorbidity related to depression recorded on their delivery admission, or other admission to hospital during pregnancy. There were a total of 7495 pregnancies identified by either set of records. Using data linkage, we determined that these records represented 6596 individual pregnancies. Only 899 pregnancies were found in both groups (13.6% of all cases). 80% of women dispensed an antidepressant did not have depression recorded as a comorbidity on their hospital records. A simple capture-recapture calculation suggests the prevalence of depression in this population of pregnant women to be around 16%. CONCLUSION: No single data source is likely to provide a complete health profile for an individual. For women with depression in pregnancy and dispensed antidepressants, the hospital admission data do not adequately capture all cases.