Chlamydia trachomatis and the risk of spontaneous preterm birth, babies who are born small for gestational age, and stillbirth: A population-based cohort study

Background: Chlamydia trachomatis is one of the most commonly diagnosed sexually transmitted infections worldwide, but reports in the medical literature of an association between genital chlamydia infection and adverse obstetric outcomes are inconsistent. Methods: The Western Australia Data Linkage Branch created a cohort of women of reproductive age by linking records of birth registrations with the electoral roll for women in Western Australia who were born from 1974 to 1995. The cohort was then linked to both chlamydia testing records and the state perinatal registry for data on preterm births and other adverse obstetric outcomes. We determined associations between chlamydia testing, test positivity, and adverse obstetric outcomes using multivariate logistic regression analyses. Findings: From 2001 to 2012, 101558 women aged 15 to 38 years had a singleton birth. Of these women, 3921 (3·9%) had a spontaneous preterm birth, 9762 (9·6% of 101371 women with available data) had a baby who was small for gestational age, and 682 (0·7%) had a stillbirth. During their pregnancy, 21267 (20·9%) of these women had at least one chlamydia test record, and 1365 (6·4%) of those tested were positive. Before pregnancy, 19157 (18·9%) of these women were tested for chlamydia, of whom 1595 (8·3%) tested positive for chlamydia. Among all women with a test record, after adjusting for age, ethnicity, maternal smoking, and history of other infections, we found no significant association between a positive test for chlamydia and spontaneous preterm birth (adjusted odds ratio 1·08 [95% CI 0·91–1·28]; p=0·37), a baby who was small for gestational age (0·95 [0·85–1·07]; p=0·39), or stillbirth (0·93 [0·61–1·42]; p=0·74). Interpretation: A genital chlamydia infection that is diagnosed and, presumably, treated either during or before pregnancy does not substantially increase a woman’s risk of having a spontaneous preterm birth, having a baby who is small for gestational age, or having a stillbirth. Funding: Australian National Health and Medical Research Counci

Impact of family-friendly prison policies on health, justice and child protection outcomes for incarcerated mothers and their dependent children: a cohort study protocol

Introduction Female imprisonment has numerous health and social sequelae for both women prisoners and their children. Examples of comprehensive family-friendly prison policies that seek to improve the health and social functioning of women prisoners and their children exist but have not been evaluated. This study will determine the impact of exposure to a family-friendly prison environment on health, child protection and justice outcomes for incarcerated mothers and their dependent children. Methods and analysis A longitudinal retrospective cohort design will be used to compare outcomes for mothers incarcerated at Boronia Pre-release Centre, a women’s prison with a dedicated family-friendly environment, and their dependent children, with outcomes for mothers incarcerated at other prisons in Western Australia (that do not offer this environment) and their dependent children. Routinely collected administrative data from 1985 to 2013 will be used to determine child and mother outcomes such as hospital admissions, emergency department presentations, custodial sentences, community service orders and placement in out-of home care. The sample consists of all children born in Western Australia between 1 January 1985 and 31 December 2011 who had a mother in a West Australian prison between 1990 and 2012 and their mothers. Children are included if they were alive and aged less than 18 years at the time of their mother’s incarceration. The sample comprises an exposed group of 665 women incarcerated at Boronia and their 1714 dependent children and a non-exposed comparison sample of 2976 women incarcerated at other West Australian prisons and their 7186 dependent children, creating a total study sample of 3641 women and 8900 children. Ethics and dissemination This project received ethics approval from the Western Australian Department of Health Human Research Ethics Committee, the Western Australian Aboriginal Health Ethics Committee and the University of Western Australia Human Research Ethics Committee

Incidence and mortality of uveal melanoma in Australia (1982–2014)

Aims: We aimed to estimate the incidence and mortality of uveal melanoma (UM) in Australia from 1982 to 2014. Methods: Deidentified unit data for all cases of ocular melanoma were extracted from the Australian Cancer Database from 1 January 1982 to 31 December 2014. UM cases were extracted and trends in incidence and disease-specific mortality were calculated. Incidence rates were age-standardised against the 2001 Australian Standard Population. Mortality was assessed using Cox regression. Results: From 1982 to 2014, there were 5087 cases of ocular melanoma in Australia, of which 4617 were classified as UM. The average age-standardised incidence rate of UM was 7.6 (95% CI 7.3 to 7.9) per million. There was an increase (p=0.0502) in the incidence of UM from 1982 to 1993 with an annual percent change (APC) of +2.5%, followed by a significant decrease in the incidence of UM from 1993 to 2014 (APC −1.2%). The average 5-year survival from 1982 to 2011 did not significantly change from an average of 81%, with an average APC (AAPC) of +0.1%. A multivariate Cox regression revealed that residence in Western Australia (p=0.001) or Tasmania (p=0.05), age ≥60 years (p \u3c 0.001) and histological classification as mixed (p \u3c 0.001) or epithelioid cells (p \u3c 0.001) were significantly associated with reduced survival. Conclusion: In conclusion, we found that the incidence of UM peaked in the 1990s. Although treatment for primary UM has improved in the last 30 years, overall survival did not change significantly in the last 30 years

Incidence and mortality of conjunctival melanoma in Australia (1982 to 2014)

Purpose: The purpose of this study was to estimate the incidence and mortality of conjunctival melanoma in Australia from 1982 to 2014. Methods: De-identified unit data for all cases of ocular melanoma were extracted from the Australian Cancer Database from 1982 to 2014. Conjunctival melanoma cases were extracted, and the incidence and mortality were analyzed. Incidence rates were age-standardized against the 2001 Australian Standard Population. Mortality was assessed using log-rank and Cox regression. Results: From 1982 to 2014, there were 299 cases of conjunctival melanoma. The age-standardized incidence rate was 0.48 (95% confidence interval [CI] = 0.41 to 0.54) per million per year. Women (0.52, 95% CI = 0.42 to 0.62) had a higher incidence than men (0.42, 95% CI = 0.33 to 0.51). The incidence of conjunctival melanoma increased in men (+1.46%) and significantly women (+1.41%, P = 0.023) over the study period. The mean 5-, 10-, and 15-year disease-specific survival were 90%, 82%, and 80%, respectively, during the 33-year interval. Comparisons of survival among age, sex, and state revealed no significant differences when tested using log-rank or Cox regression. Conclusions: In conclusion, we found an increase in the rate of conjunctival melanoma diagnoses in Australia from 1982 to 2014. Over the same period, disease survival remained unchanged at a mean of 90%

Regular General Practitioner contact - analysis of methods for measurement using administrative data

Introduction There is a small body of literature examining the relationship between “regularity” of contact with General Practitioners (GPs), i.e. the pattern of visits over time, and health outcomes. Methods previously used to measure regularity may be conflated with the number of GP visits (frequency) which may impact on effect estimates. Objectives and Approach Two published regularity measures, one derived from the variance in the days between GP visits and the second a categorical indicator, were assessed alongside a new measure designed to be uncorrelated with frequency. A cohort at risk of diabetes-related hospitalisation was identified from primary care and hospitalisation data. Associations between regularity and frequency were assessed for each measure using negative binomial regression. Hospitalisation outcomes were regressed on regularity scores using negative binomial models, with and without frequency included, to assess whether associations between regularity and frequency biased estimates. Simulated data tested each measure’s responsiveness to changes in GP visit patterns. Results The new regularity measure showed a substantially weaker association between regularity and frequency than the two previously published scores. According to the new measure, more regular GP contact was associated with a reduction in the rate of hospitalisation and this association was unchanged by the inclusion of frequency as a covariate. Under the existing measures regular contact was also associated with reduced hospitalisation, but the association differed depending on whether frequency was included in the model, suggesting that associations between regularity and frequency may confound relationships with health outcomes if uncontrolled for. Simulated data suggested that the measures responded differently to changes in visitation pattern with the existing categorical indicator being the least responsive. Conclusion/Implications Despite a large body of literature on provider continuity, little research has examined regularity of GP contact. This is the first work to compare measures of regularity and represents an important methodological advancement. Researchers should consider regularity of contact as a dimension of continuity of care when designing studies

Optimizing patient risk stratification for colonoscopy screening and surveillance of colorectal cancer: The role for linked data

No abstract available for this article

Hospital and emergency department discharge against medical advice in Western Australian Aboriginal children aged 0–4 years from 2002 to 2018: A cohort study

Background: Discharge against medical advice (DAMA) is a priority issue for the health system. Little is known about the factors associated with DAMA for Aboriginal and/or Torres Strait Islander (Aboriginal) children in Australia. Objectives: Investigate the associations between DAMA for hospital admissions and emergency department (ED) presentations and: (i) child, family and episode of service characteristics and (ii) 30-day readmission/ re-presentation. Methods: We conducted a cohort study of Aboriginal children born in Western Australia (2002–2013) who had ≥ 1 hospital admissions (n = 16,931) or ED presentations (n = 26,546) within the first 5 years of life. The outcome of interest was hospital and ED DAMA and adjusted odds ratio were derived using multilevel mixed-effects logistic regression. Results: In the Hospital Cohort, there were 43,149 hospitalisations for 16,931 children, with 684 hospitalisations (1.6%) recorded as DAMA. In the ED Cohort, there were 232,082 ED presentations in 26,546 children, with 10,918 ED presentations (4.7%) recorded as DAMA. DAMA occurring in hospitals between 2014 and 2018, the adjusted odds decreased by 75% compared to the period between 2002 and 2005. The adjusted odds of ED DAMA increased by 46% over the same period. Hospital admissions in regional and remote hospitals were almost seven times the adjusted odds of DAMA compared with hospital admissions in Perth metropolitan hospitals. The adjusted odds of ED DAMA decreased by 12% for ED presentations in regional and remote hospitals compared to those in Perth metropolitan hospitals. There was no evidence of hospital DAMA being associated with hospital readmission within 30 days and limited evidence of ED DAMA being associated with re-presenting to an ED within 30 days. Conclusions: The study identified several important determinants of DAMA, including admission status, triage status, location and calendar year. These findings could inform targeted measures to decrease DAMA, particularly in regional and remote communities

Counting the cost: estimating the number of deaths among recently released prisoners in Australia

Objective: To estimate the number of deaths among people released from prison in Australia in the 2007–08 financial year, within 4 weeks and 1 year of release. Design, participants and setting: Application of crude mortality rates for ex-prisoners (obtained from two independent, state-based record-linkage studies [New South Wales and Western Australia]) to a national estimate of the number and characteristics of people released from prison in 2007–08. Main outcome measures: Estimated number of deaths among adults released from Australian prisons in 2007–08, within 4 weeks and 1 year of release, classified by age, sex, Indigenous status and cause of death. Results: It was estimated that among people released from prison in 2007–08, between 449 (95% CI, 380–527) and 472 (95% CI, 438–507) died within 1 year of release. Of these, between 68 (95% CI, 56–82) and 138 (95% CI, 101–183) died within 4 weeks of release. Most of these deaths were not drug-related. Conclusion: The estimated annual number of deaths among recently released prisoners in Australia is considerably greater than the annual number of deaths in custody, highlighting the extreme vulnerability of this population on return to the community. There is an urgent need to establish a national system for routine monitoring of ex-prisoner mortality and to continue the duty of care beyond the prison walls

Comorbidity and repeat admission to hospital for adverse drug reactions in older adults: retrospective cohort study

Objectives To identify factors that predict repeat admission to hospital for adverse drug reactions (ADRs) in older adults

Combining cross-sectoral, prospective data linkage with other data sources to examine health outcomes for socially excluded populations: A case study from Australia

Introduction Studies of the health of prisoners have proliferated in the past decade. However, relatively few studies have examined health outcomes after release from custody. As such, although >30 million people are released from prison globally each year, the health and health service experiences of this population remain poorly understood. Objectives and Approach Well-powered longitudinal studies are essential for answering these questions but are expensive and difficult to conduct. Internationally, few such studies have been undertaken, and most suffer from either substantial and biased attrition, or recruitment bias. Cross-sectoral linkage of health and justice data circumvents some of these problems but presents its own ethical and methodological challenges. Large longitudinal studies, combining rich survey and clinical data with prospective data linkage, provide unique opportunities to examine and understand health outcomes for these highly marginalised individuals. Results This presentation will describe the process and challenges of establishing the world’s largest (N=2,702) prospective study of adults released from prison: the Health After Release from Prison (HARP) cohort study. The cohort spans two Australian states and includes 538 women and 1,002 Indigenous Australians. An overview of the data collected through face-to-face surveys, medical record review, and prospective linkage with State-based health and correctional records, national Medicare and pharmaceutical records, and the National Death Index, will be provided. Some examples of how these data have been used to answer novel public health questions will be presented. The strengths and limitations of the cohort, and the applicability of this research design for other inclusion health populations, will be discussed. Conclusion/Implications Given their extreme vulnerability, understanding the health of people who cycle through prisons is important to addressing health inequalities at the population level. Novel research designs that combine prospective data linkage with other data sources provide new opportunities to examine the health of socially excluded populations