Post-discharge pharmacotherapy in people with atrial fibrillation hospitalised for acute myocardial infarction: an Australian cohort study 2018-2022.

BACKGROUND: Dual antiplatelet therapy with P2Y12 inhibitors (P2Y12i) and aspirin following acute myocardial infarction (AMI) prevents future ischaemic events. People with atrial fibrillation (AF) also require oral anticoagulants (OAC), increasing bleeding risk. Guidelines recommend post-discharge prescribing of direct OAC with clopidogrel and discontinuation of P2Y12i after 12 months, but little is known about use in clinical practice. AIM: To describe post-discharge use of OACs and P2Y12i in people with AF and a history of OAC use hospitalised for AMI. METHODS AND RESULTS: We identified 1,330 people hospitalised for AMI with a diagnosis of AF and history of OAC use in New South Wales, Australia, July 2018-June 2020. We identified three aspects of post-discharge antithrombotic medicine use with possible safety implications: (1) not being dispensed OACs; (2) dispensing OAC and P2Y12i combinations associated with increased bleeding (involving warfarin, ticagrelor or prasugrel); and (3) P2Y12i use longer than 12 months.After discharge, 74.3% of people were dispensed an OAC, 45.4% were dispensed a P2Y12i, and 35.8% were dispensed both. People with comorbid heart failure or cancer were less likely to receive OACs. Only 11.2% of people dispensed both an OAC and P2Y12i received combinations associated with increased bleeding; this was more common among people with chronic kidney disease or prior warfarin or statin use. 44.6% of people dispensed both medicines continued P2Y12i for over 12 months; this was more common in people who received a revascularisation or lived in areas of social disadvantage. CONCLUSION: We identified potential gaps in pharmacotherapy, including underuse of recommended therapies at discharge, use of combinations associated with increased bleeding, and P2Y12i use beyond 12 months. Prescribing vigilance across both hospital and community care is required.

The Medicines Intelligence Data Platform: A Population-Based Data Resource From New South Wales, Australia.

BACKGROUND: The Medicines Intelligence (MedIntel) Data Platform is an anonymised linked data resource designed to generate real-world evidence on prescribed medicine use, effectiveness, safety, costs and cost-effectiveness in Australia. RESULTS: The platform comprises Medicare-eligible people who are ≥18 years and residing in New South Wales (NSW), Australia, any time during 2005-2020, with linked administrative data on dispensed prescription medicines (Pharmaceutical Benefits Scheme), health service use (Medicare Benefits Schedule), emergency department visits (NSW Emergency Department Data Collection), hospitalisations (NSW Admitted Patient Data Collection) plus death (National Death Index) and cancer registrations (NSW Cancer Registry). Data are currently available to 2022, with approval to update the cohort and data collections annually. The platform includes 7.4 million unique people across all years, covering 36.9% of the Australian adult population; the overall population increased from 4.8 M in 2005 to 6.0 M in 2020. As of 1 January 2019 (the last pre-pandemic year), the cohort had a mean age of 48.7 years (51.1% female), with most people (4.4 M, 74.7%) residing in a major city. In 2019, 4.4 M people (73.3%) were dispensed a medicine, 1.2 M (20.5%) were hospitalised, 5.3 M (89.4%) had a GP or specialist appointment, and 54 003 people died. Anti-infectives were the most prevalent medicines dispensed to the cohort in 2019 (43.1%), followed by nervous system (32.2%) and cardiovascular system medicines (30.2%). CONCLUSION: The MedIntel Data Platform creates opportunities for national and international research collaborations and enables us to address contemporary clinically- and policy-relevant research questions about quality use of medicines and health outcomes in Australia and globally.

Use of an emulated trial to investigate the association between use of nitrogen-based bisphosphonates and risk of epithelial ovarian cancer.

BACKGROUND: Epithelial ovarian cancer (EOC) is the eighth most common cancer in women, with poor survival outcomes. Observational evidence suggests that nitrogen-based bisphosphonate (NBB) use may be associated with reduced risk of EOC, particularly the endometrioid and serous histotypes; however, confounding by indication is a concern. An alternative approach to investigate the chemo-preventive potential of NBBs is to emulate a target trial by identifying all women who initiate use of NBBs and investigate the risk of EOC for continued users compared with discontinued users. METHODS: Using population-based linked data, we identified all Australian women aged over 50 years who first used NBBs over 2004-12. We used the year after first use to define treatment for each woman as either continued or discontinued use. We emulated randomization using stabilized inverse probability weights to balance the treatment groups using covariates including age, comorbidities and socioeconomic status. We followed women from treatment assignment until EOC diagnosis, death or 31 December 2013. We assessed the risk of EOC (overall and by histotype) using flexible parametric time-to-event models allowing for time-varying effects, and produced time-varying coefficients. RESULTS: Of the 313 383 women in the study, 472 were diagnosed with EOC during follow-up (261 serous EOC), with an average age at diagnosis of 72 years. Continued use of NBBs was associated with reduced risk of EOC overall (HR = 0.87, 95% CI: 0.69, 1.10), and serous EOC (HR = 0.71, 95% CI: 0.53, 0.96), compared with discontinued treatment, with estimates remaining constant over the 9-year follow-up. CONCLUSIONS: Results from our emulated trial suggest that in women who initiated NBB treatment, those who continued use had 13% and 29% lower hazards of being diagnosed with EOC overall and serous EOC, respectively, compared with women who discontinued use.

Cohort profile: understanding health service system needs for people with intellectual disability using linked data in New South Wales, Australia.

This cohort profile describes one of the largest linked datasets in the world concerning the health of people with intellectual disability. The cohort comprises a retrospective group of 100,089 individuals with intellectual disability who received disability and/or health services in New South Wales, Australia. Of these participants, 34% were female, with a median age at cohort entry of 3 years (interquartile range, 0 to 19 years). A separate comparator cohort included 455,677 individuals, matched by 5-year age group, sex, and residential postcode at a 5:1 ratio. Initial results indicate that between 2001 and 2018, people with intellectual disability experienced more than double the rate of hospitalisations (538 versus 235 per 1000 person-years), as well as markedly higher rates of emergency department presentations (707 versus 379 per 1000 person-years) and use of ambulatory mental health services (1012 versus 157 per 1000 person-years), relative to the comparator cohort. The largest disparities in hospital admissions were for mental disorders, dialysis, and diseases of the nervous system and sense organs. Furthermore, individuals with intellectual disability had more than double the rate of dispensed medications found in the comparator cohort. Of these medications, 46.6% were for the treatment of nervous system conditions, as opposed to 24.7% for the comparator cohort. The mean age at death was 52 years (standard deviation [SD], 19 years) for people with intellectual disability and 64 years (SD, 22 years) for the comparator participants.

Smoking Cessation Pharmacotherapy Use in Pregnancy.

Importance: Significant evidence gaps exist regarding the safety of smoking cessation pharmacotherapies during pregnancy, especially for the risk of congenital malformations. Consequently, professional bodies advise against the use of varenicline and bupropion and recommend caution with nicotine replacement therapy (NRT). Contemporary estimates of the use of smoking cessation pharmacotherapies during pregnancy are lacking. Objective: To quantify the proportion of individuals using prescribed smoking cessation pharmacotherapies during pregnancy and during the first trimester specifically, in 4 countries. Design, Setting, and Participants: This retrospective, population-based cohort study used linked birth records, hospital admission records, and dispensing records of prescribed medications from all pregnancies resulting in birth between 2015 and 2020 in New South Wales, Australia; New Zealand; Norway; and Sweden. Data analyses were conducted in October and November 2023. Exposure: Prescribed smoking cessation pharmacotherapy use (varenicline, NRT, and bupropion) during pregnancy was defined as days' supply overlapping the period from date of conception to childbirth. Main Outcomes and Measures: Prevalence of use among all pregnancies and pregnancies with maternal smoking were calculated. Among women who used a pharmacotherapy, the proportion of women with use during the first trimester of pregnancy was also calculated. Results: Among 1 700 638 pregnancies in 4 countries, 138 033 (8.1%) had maternal smoking and 729 498 (42.9%) were younger than 30 years. The prevalences ranged from 0.02% to 0.14% for varenicline, less than 0.01% to 1.86% for prescribed NRT, and less than 0.01% to 0.07% for bupropion. Among pregnant individuals who smoked, use of pharmacotherapies was up to 10 times higher, with maximum prevalences of 1.25% for varenicline in New South Wales, 11.39% for NRT in New Zealand, and 0.39% for bupropion in New Zealand. Use in the first trimester occurred among more than 90% of individuals using varenicline, approximately 60% among those using NRT, and 80% to 90% among those using bupropion. Conclusions and Relevance: In this cohort study of pregnant individuals in 4 high-income countries, the low prevalence of varenicline and bupropion use during pregnancy and higher prevalence of NRT use aligned with current clinical guidelines. As most use occurred in the first trimester, there is a need for evidence on the risk of congenital malformations for these medications.

Trajectories of Opioid Use Before and After Cancer Diagnosis: A Population-Based Cohort Study.

BACKGROUND: Opioid use prior to cancer diagnosis increases the likelihood of long-term use during survivorship, however, patterns of use before and after diagnosis are not understood. METHODS: We used population-based dispensing data linked with cancer and death notifications to identify two cohorts of adults residing in New South Wales initiating opioids within 24 months prior to a first cancer diagnosed between 2014 and 2016: 'survivors' (alive 24 months following diagnosis) and 'decedents' (died within 24 months). We used group-based trajectory modelling to identify trajectories of monthly opioid dispensings and dispensed oral morphine equivalent milligrams (OMEmg) during the 24 months before/after cancer diagnosis. RESULTS: There were 21,843 survivors with four prediagnosis opioid dispensing trajectories: infrequent (58% of the cohort), late increasing (26%), moderate (10%), and sustained dispensing (6%). We observed an overall increase in dispensed OMEmg of 83 OMEmg (95% CI: 76-91) during the month of diagnosis, with strong opioid formulations comprising most treatment postdiagnosis. Within each prediagnosis opioid trajectory group, we observed five to six postdiagnosis trajectory groups, including no opioid dispensing. Moderate and sustained prediagnosis groups had large proportions of people continuing or increasing opioid dispensing after diagnosis, while small proportions discontinued opioid treatment. We observed similar trajectories in the decedent cohort. CONCLUSIONS: There is considerable heterogeneity in opioid use before and after cancer diagnosis. Our findings suggest noncancer factors drive a significant proportion of postdiagnosis opioid use, but use increased significantly from the month of cancer diagnosis and never returned to prediagnosis levels.

Opioid analgesic exposure during the first trimester of pregnancy and the risk of major congenital malformations in infants: a systematic review and meta-analysis†.

BACKGROUND: Prescribed opioid analgesics are frequently used to manage pain in pregnancy. However, the available literature regarding the teratogenic potential of opioid use during pregnancy has not been systematically summarised. This systematic review and meta-analysis aimed to assess the quality of the evidence on these potential risks and calculate a pooled estimate of risk for any opioid analgesic and individual opioids. METHODS: We searched PubMed, Embase and CINAHL for published studies assessing the risk of major congenital malformations in infants following first-trimester exposure to opioid analgesics compared with a reference group, excluding studies examining opioid agonist therapy or illicit opioid use. We assessed the risk of bias using the Risk of Bias in Non-Randomised Studies of Intervention tool. We pooled adjusted risk estimates from studies rated at serious risk of bias or better in a random-effects meta-analysis. RESULTS: Of 12 identified studies, 11 were at high risk of bias (eight serious; three critical). Relative to unexposed infants, those exposed to any opioid use during the first trimester of pregnancy were not at an increased risk of major congenital malformations overall (relative risk 1.04, 95%CI 0.98-1.11); cardiovascular malformations (relative risk 1.07, 95%CI 0.96-1.20); or central nervous system malformations (relative risk 1.06, 95%CI 0.92-1.21). Raised risk estimates were observed for gastrointestinal malformations (relative risk 1.40, 95%CI 0.38-5.16) and cleft palate (relative risk 1.57, 95%CI 0.48-5.13) following any opioid exposure and atrial septal defects (relative risk 1.20, 95%CI 1.05-1.36) following codeine exposure. CONCLUSIONS: Although the meta-analysis did not indicate substantial increased risk for most malformations examined, this risk remains uncertain due to the methodological limitations of the included studies. Healthcare professionals and pharmaceutical regulators should be aware of the issues related to the quality of research in this field.

Long-term prescribed opioid use after hospitalization or emergency department presentation among opioid naïve adults (2014-2020)-A population-based descriptive cohort study.

AIMS: The aim of this work is to describe opioid initiation and long-term use after emergency department (ED) visits or hospitalizations in New South Wales, Australia, by patient, admission and clinical characteristics. METHODS: This is a population-based cohort study, including all hospitalizations and ED visits between 2014 and 2020, linked to medicine dispensings, deaths and cancer registrations (Medicines Intelligence Data Platform), among adults with no opioid dispensings in the previous year. Outcome measures were opioid initiations (dispensed within 7 days of discharge) and long-term use (90 days of continuous exposure, 90-270 days after initiation). RESULTS: The cohort included 16 153 096 admissions by 4.2 million opioid-naïve adults; 39.0% were ED presentations without hospital admission, 16.8% hospital admissions via ED and 44.2% direct hospital admissions. Opioids were initiated post-discharge for 6.2% of ED, 8.3% of hospital via ED and 10.0% of direct hospital admissions; of these 1.0%, 2.5% and 0.5% progressed to long-term opioid use, respectively. Initiation was lowest in obstetric admissions without surgery (1.0%), and highest among trauma admissions (25.4%), obstetric admissions with surgical intervention (19.8%) and non-trauma surgical admissions (12.0%). Long-term use was highest among medical admissions via ED (3.5%), trauma admissions (2.3%) and ED alone (1.0%). From 2014 to 2020, overall opioid initiations decreased 16% from 8.7% to 7.2%, and long-term opioid use decreased 33% from 1.3% to 0.8%. CONCLUSIONS: Both opioid initiation and long-term use decreased over time; however, the higher rates of long-term use following trauma, and medical admissions via ED, warrant further surveillance. Strategies supporting appropriate prescribing and access to multidisciplinary pain services will facilitate best practice care.

Impact of coordinated care on adherence to antihypertensive medicines among adults experiencing polypharmacy in Australia.

BACKGROUND: Adherence to antihypertensives is key for blood pressure control. Most people with hypertension have several comorbidities and require multiple medicines, leading to complex care pathways. Strategies for coordinating medicine use can improve adherence, but cumulative benefits of multiple strategies are unknown. METHODS: Using dispensing claims for a 10% sample of eligible Australians, we identified adult users of antihypertensives during July 2018-June 2019 who experienced polypharmacy (≥5 unique medicines). We measured medicine use reflecting coordinated medicine management in 3 months before and including first observed dispensing, including: use of simple regimens for each cardiovascular medicine; prescriber continuity; and coordination of dispensings at the pharmacy. We measured adherence (proportion of days covered) to antihypertensive medicines in the following 12 months, and used logistic regression to assess independent associations and interactions of adherence with these measures of care. RESULTS: We identified 202 708 people, of which two-thirds (66.6%) had simple cardiovascular medicine regimens (one tablet per day for each medicine), two-thirds (63.3%) were prescribed >75% of medicines from the same prescriber, and two-thirds (65.5%) filled >50% of their medicine on the same day. One-third (28.4%) of people experienced all three measures of coordinated care. Although all measures were significantly associated with higher adherence, adherence was greatest among people experiencing all three measures (odds ratio = 1.63; 95% confidence interval: 1.55-1.72). This interaction was driven primarily by effects of prescriber continuity and dispensing coordination. CONCLUSIONS: Coordinating both prescribing and dispensing of medicines can improve adherence to antihypertensives, which supports strategies consolidating both prescribing and supply of patients' medicines.

Prescription retinoid and contraception use in women in Australia: A population-based study.

BACKGROUND/OBECTIVES: Oral retinoids are teratogenic, and pregnancy avoidance is an important part of retinoid prescribing. Australia does not have a standardised pregnancy prevention programme for women using oral retinoids, and the contraception strategies for women who use oral retinoids are not well understood. The objectives were to determine trends in the use of prescription retinoids among Australian reproductive-aged women and whether women dispensed oral retinoids used contraception concomitantly. METHODS: This was a population-based study using Australian Pharmaceutical Benefits (PBS) dispensing claims for a random 10% sample of 15-44-year-old Australian women, 2013 - 2021. We described rates and annual trends in dispensing claims for PBS-listed retinoids and contraceptives. We also estimated concomitant oral retinoid and contraceptive use on the day of each retinoid dispensing and determined if there was a period of contraceptive treatment that overlapped. Estimates were then extrapolated to the national level. RESULTS: There were 1,545,800 retinoid dispensings to reproductive-aged women; 57.1% were oral retinoids. The rate of retinoid dispensing to reproductive-aged women increased annually, from 28 dispensings per 1000 population in 2013 to 41 per 1000 in 2021. The rate of oral retinoid dispensing doubled over the study period, from 14 dispensings per 1000 population in 2013 to 28 per 1000 in 2021, while topical retinoid dispensing did not change. Only 25% of oral retinoid dispensings had evidence of concomitant contraceptive use in 2021. CONCLUSIONS: Rates of oral retinoid dispensing have doubled among reproductive-aged women over the past decade. A large percentage of oral retinoid use does not appear to have concomitant contraception use, posing a risk of teratogenic effects in pregnancies.

Oxycodone initiation in Australia (2014-2018): Sociodemographic factors and preceding health service use.

AIMS: Oxycodone is the most commonly prescribed strong opioid in Australia. This study describes health service antecedents and sociodemographic factors associated with oxycodone initiation. METHODS: Population-based new user cohort study linking medicine dispensings, hospitalizations, emergency department visits, medical services and cancer notifications from New South Wales (NSW) for 2014-2018. New users had no dispensings of any opioid in the preceding year. We analysed health service use in the 5 days preceding initiation and proportion of people on treatment over 1 year and fitted an area-based, multivariable initiation model with sociodemographic covariates. RESULTS: Oxycodone accounted for 30% of opioid initiations. Annually, 3% of the NSW population initiated oxycodone, and 5-6% were prevalent users; the new user cohort comprised 830 963 people. Discharge from hospital (39.3%), therapeutic procedures (21.4%) and emergency department visits (19.7%) were common; a hospital admission for injury (6.0%) or a past-year history of cancer (7.2%) were less common. At 1 year after initiation, 4.6% of people were using oxycodone. In the multivariable model, new use of oxycodone increased with age and was higher for people outside major cities, for example, an incidence rate ratio of 1.43 (95% confidence interval 1.36-1.51) for inner regional areas relative to major cities; there was no evidence of variation in rates of new use by social disadvantage. CONCLUSION: About half of new oxycodone use in NSW was preceded by a recent episode of hospital care or a therapeutic procedure. Higher rates of oxycodone initiation in rural and regional areas were not explained by sociodemographic factors.

Geographic variation in sodium-glucose cotransporter 2 inhibitor and glucagon-like peptide-1 receptor agonist use in people with type 2 diabetes in New South Wales, Australia.

AIM: Sodium-glucose cotransporter 2 inhibitors (SGLT2is) and glucagon-like peptide-1 receptor agonists (GLP-1RAs) improve glycaemic control and cardio-renal outcomes for people with type 2 diabetes (T2D). However, geographic and socio-economic variation in use is not well understood. METHODS: We identified 367 829 New South Wales residents aged ≥40 years who dispensed metformin in 2020 as a proxy for T2D. We estimated the prevalence of use of other glucose-lowering medicines among people with T2D and the prevalence of SGLT2i and GLP-1RA use among people using concomitant T2D therapy (i.e. metformin + another glucose-lowering medicine). We measured the prevalence by small-level geography, stratified by age group, and characterized by remoteness and socio-economic status. RESULTS: The prevalence of SGLT2i (29.7%) and GLP-1RA (8.3%) use in people with T2D aged 40-64 increased with geographic remoteness and in areas of greater socio-economic disadvantage, similar to other glucose-lowering medicines. The prevalence of SGLT2i (55.4%) and GLP-1RA (15.4%) among people using concomitant T2D therapy varied across geographic areas, with lower SGLT2i use in more disadvantaged areas and localized areas of high GLP-1RA use (2.5 times the median). Compared with people aged 40-64 years, the prevalence of SGLT2i and GLP-1RA use was lower in older age groups, but with similar patterns of variation across geographic areas. CONCLUSIONS: The prevalence of SGLT2i and GLP-1RA use varied by geography, probably reflecting a combination of system- and prescriber-level factors. Socio-economic variation in GLP-1RA use was overshadowed by localized patterns of prescribing. Continued monitoring of variation can help shape interventions to optimize use among people who would benefit the most.

Antipsychotic use during pregnancy and risk of specific neurodevelopmental disorders and learning difficulties in children: a multinational cohort study.

Background: Antipsychotics are commonly prescribed to treat a range of psychiatric conditions in women of reproductive age and during pregnancy, including schizophrenia, bipolar disorder, anxiety, depression, autism spectrum disorder, and insomnia. This study aimed to evaluate whether children exposed to antipsychotic medication prenatally are at increased risk of specific neurodevelopmental disorders and learning difficulties. Methods: Our population-based cohort study used nationwide register data (1 January 2000-31 December 2020) on pregnant women diagnosed with a psychiatric disorder and their live-born singletons from Denmark, Finland, Iceland, Norway, and Sweden. Cox proportional hazard regression yielded propensity score-weighted hazard ratios (aHRs) and 95% confidence intervals (CIs) for risk of intellectual-, speech or language-, learning-developmental disorders, and a composite outcome of the listed disorders. We defined poor performance as scoring within the lowest quartile on national school tests in mathematics and language arts. We estimated propensity score-weighted risk ratios (aRRs) using Poisson regression. We analysed data from Denmark separately and pooled results using random effects meta-analysis. Findings: Among 213,302 children (median follow-up: 6.7 years), 11 626 (5.5%) were exposed to antipsychotics prenatally. Adjusted risk estimates did not suggest an increased risk of neurodevelopmental disorders: aHR of 1.06 (95% CI 0.94-1.20) for the composite outcome, or for poor academic performance: aRR of 1.04 (95% CI 0.91-1.18) in mathematics, and of 1.00 (95% CI 0.87-1.15) in language arts. Results were generally consistent across individual medications, trimesters of exposure, sibling- and sensitivity analyses. Interpretation: The findings of this large multinational cohort study suggest there is little to no increased risk of child neurodevelopmental disorders or learning difficulties after prenatal exposure to antipsychotics. Our findings can assist clinicians and women managing mental illness during pregnancy. Funding: This study was funded by the NordForsk Nordic Program on Health and Welfare (Nordic Pregnancy Drug Safety Studies, project No. 83539), by the Research Council of Norway (International Pregnancy Drug Safety Studies, project No. 273366) and by the Research Council of Norway through its Centres of Excellence funding scheme (project No. 262700), and UNSW Scientia Programme Awards (PS46019, PS46019-A).

Evolution of the data and methods in real-world COVID-19 vaccine effectiveness studies on mortality: a scoping review protocol.

BACKGROUND: Early evidence on COVID-19 vaccine efficacy came from randomised trials. Many important questions subsequently about vaccine effectiveness (VE) have been addressed using real-world studies (RWS) and have informed most vaccination policies globally. As the questions about VE have evolved during the pandemic so have data, study design, and analytical choices. This scoping review aims to characterise this evolution and provide insights for future pandemic planning-specifically, what kinds of questions are asked at different stages of a pandemic, and what data infrastructure and methods are used? METHODS AND ANALYSIS: We will identify relevant studies in the Johns Hopkins Bloomberg School of Public Health VIEW-hub database, which curates both published and preprint VE RWS identified from PubMed, Embase, Scopus, Web of Science, the WHO COVID Database, MMWR, Eurosurveillance, medRxiv, bioRxiv, SSRN, Europe PMC, Research Square, Knowledge Hub, and Google. We will include RWS of COVID-19 VE that reported COVID-19-specific or all-cause mortality (coded as 'death' in the 'effectiveness studies' data set).Information on study characteristics; study context; data sources; design and analytic methods that address confounding will be extracted by single reviewer and checked for accuracy and discussed in a small group setting by methodological and analytic experts. A timeline mapping approach will be used to capture the evolution of this body of literature.By describing the evolution of RWS of VE through the COVID-19 pandemic, we will help identify options for VE studies and inform policy makers on the minimal data and analytic infrastructure needed to support rapid RWS of VE in future pandemics and of healthcare strategies more broadly. ETHICS AND DISSEMINATION: As data is in the public domain, ethical approval is not required. Findings of this study will be disseminated through peer-reviewed publications, conference presentations, and working-papers to policy makers. REGISTRATION: https://doi.org/10.17605/OSF.IO/ZHDKR.

Secondary Analysis of the Salt Substitute and Stroke Study (SSaSS): Effects of Potassium-Enriched Salt on Cardiac Outcomes.

BACKGROUND: The SSaSS (Salt Substitute and Stroke Study) has shown that use of a potassium-enriched salt lowers the risk of stroke, total cardiovascular events, and premature death. The effects on cause-specific cardiac outcomes are reported here. METHODS: SSaSS was an unblinded, cluster-randomised trial assessing the effects of potassium-enriched salt compared with regular salt among 20 995 Chinese adults with established stroke and older age and uncontrolled hypertension. Post hoc efficacy analyses were performed using an intention-to-treat method and a hierarchical Poisson regression model adjusting for clustering to obtain rate ratios and 95% CIs. We assessed acute coronary syndrome, heart failure, arrhythmia, and sudden death. RESULTS: Over a mean 4.74 years follow-up, there were 695 acute coronary syndrome events, 454 heart failure events, 230 arrhythmia events, and 1133 sudden deaths recorded. The rates of events were lower in potassium-enriched salt group for all outcomes but CIs were wide for most: acute coronary syndrome (6.32 versus 7.65 events per 1000 person-years; rate ratio, 0.80 [95% CI, 0.65-0.99]); heart failure (9.14 versus 11.32 events per 1000 person-years; rate ratio, 0.88 [95% CI, 0.60-1.28]); arrhythmia (4.43 versus 6.20 events per 1000 person-years; rate ratio, 0.59 [95% CI, 0.35-0.98]); and sudden death (11.01 versus 11.76 events per 1000 person-years; rate ratio, 0.94 [95% CI, 0.82-1.07]; all P>0.05 with adjustment for multiple comparisons). CONCLUSIONS: These results suggest that use of potassium-enriched salt is more likely to prevent than cause cardiac disease but the post hoc nature of these analyses precludes definitive conclusions. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02092090.

The Australian Health Care Homes trial: quality of care and patient outcomes. A propensity score-matched cohort study.

OBJECTIVE: To assess the impact of the Health Care Homes (HCH) primary health care initiative on quality of care and patient outcomes. DESIGN, SETTING: Quasi-experimental, matched cohort study; analysis of general practice data extracts and linked administrative data from ten Australian primary health networks, 1 October 2017 - 30 June 2021. PARTICIPANTS: People with chronic health conditions (practice data extracts: 9811; linked administrative data: 10 682) enrolled in the HCH 1 October 2017 - 30 June 2019; comparison groups of patients receiving usual care (1:1 propensity score-matched). INTERVENTION: Participants were involved in shared care planning, provided enhanced access to team care, and encouraged to seek chronic condition care at the HCH practice where they were enrolled. Participating practices received bundled payments based on clinical risk tier. MAIN OUTCOME MEASURES: Access to care, processes of care, diabetes-related outcomes, hospital service use, risk of death. RESULTS: During the first twelve months after enrolment, the mean numbers of general practitioner encounters (rate ratio, 1.14; 95% confidence interval [CI], 1.11-1.17) and Medicare Benefits Schedule claims for allied health services (rate ratio, 1.28; 95% CI, 1.24-1.33) were higher for the HCH than the usual care group. Annual influenza vaccinations (relative risk, 1.20; 95% CI, 1.17-1.22) and measurements of blood pressure (relative risk, 1.09; 95% CI, 1.08-1.11), blood lipids (relative risk, 1.19; 95% CI, 1.16-1.21), glycated haemoglobin (relative risk, 1.06; 95% CI, 1.03-1.08), and kidney function (relative risk, 1.13; 95% CI, 1.11-1.15) were more likely in the HCH than the usual care group during the twelve months after enrolment. Similar rate ratios and relative risks applied in the second year. The numbers of emergency department presentations (rate ratio, 1.09; 95% CI, 1.02-1.18) and emergency admissions (rate ratio, 1.13; 95% CI, 1.04-1.22) were higher for the HCH group during the first year; other differences in hospital use were not statistically significant. Differences in glycaemic and blood pressure control in people with diabetes in the second year were not statistically significant. By 30 June 2021, 689 people in the HCH group (6.5%) and 646 in the usual care group (6.1%) had died (hazard ratio, 1.07; 95% CI, 0.96-1.20). CONCLUSIONS: The HCH program was associated with greater access to care and improved processes of care for people with chronic diseases, but not changes in diabetes-related outcomes, most measures of hospital use, or risk of death.

Association between long-term use of calcium channel blockers (CCB) and the risk of breast cancer: a retrospective longitudinal observational study protocol.

INTRODUCTION: Calcium channel blockers (CCB), a commonly prescribed antihypertensive (AHT) medicine, may be associated with increased risk of breast cancer. The proposed study aims to examine whether long-term CCB use is associated with the development of breast cancer and to characterise the dose-response nature of any identified association, to inform future hypertension management. METHODS AND ANALYSIS: The study will use data from 2 of Australia's largest cohort studies; the Australian Longitudinal Study on Women's Health, and the 45 and Up Study, combined with the Rotterdam Study. Eligible women will be those with diagnosed hypertension, no history of breast cancer and no prior CCB use at start of follow-up (2004-2009). Cumulative dose-duration exposure to CCB and other AHT medicines will be captured at the earliest date of: the outcome (a diagnosis of invasive breast cancer); a competing risk event (eg, bilateral mastectomy without a diagnosis of breast cancer, death prior to any diagnosis of breast cancer) or end of follow-up (censoring event). Fine and Gray competing risks regression will be used to assess the association between CCB use and development of breast cancer using a generalised propensity score to adjust for baseline covariates. Time-varying covariates related to interaction with health services will also be included in the model. Data will be harmonised across cohorts to achieve identical protocols and a two-step random effects individual patient-level meta-analysis will be used. ETHICS AND DISSEMINATION: Ethical approval was obtained from the following Human research Ethics Committees: Curtin University (ref No. HRE2022-0335), NSW Population and Health Services Research Ethics Committee (2022/ETH01392/2022.31), ACT Research Ethics and Governance Office approval under National Mutual Acceptance for multijurisdictional data linkage research (2022.STE.00208). Results of the proposed study will be published in high-impact journals and presented at key scientific meetings. TRIAL REGISTRATION NUMBER: NCT05972785.

The impact of tightened prescribing restrictions for PBS-subsidised opioid medicines and the introduction of half-pack sizes, Australia, 2020-21: an interrupted time series analysis.

OBJECTIVES: To evaluate the impact of the tightened Pharmaceutical Benefits Scheme (PBS) prescribing rules for immediate release (IR) and controlled release (CR) opioid medicines (1 June 2020), which also eliminated repeat dispensing without authorisation for codeine/paracetamol and tramadol IR and introduced half-pack size item codes for IR formulations. DESIGN, SETTING: Population-based interrupted time series analysis of PBS dispensing data claims for a 10% sample of PBS-eligible residents and IQVIA national opioid medicine sales data (PBS-subsidised and private prescriptions), 28 May 2018 - 6 June 2021. MAIN OUTCOME MEASURES: Mean amount of PBS-subsidised opioid medicines dispensed per day and mean overall amount sold per day - each expressed as oral morphine equivalent milligrams (OME) - overall, by formulation type (IR, CR), and by specific formulation. RESULTS: During the twelve months following the PBS changes, daily PBS-subsidised opioid medicine dispensing was 81 565 OME lower (95% CI, -106 146 to -56 984 OME) than the mean daily level for 2018-20, a decline of 3.8% after adjusting for the pre-intervention trend; the relative reduction was greater for IR (8.4%) than CR formulations (2.6%). Total daily sales of all, IR formulation, and CR formulation opioid medicines did not change significantly after the PBS changes. Repeat dispensing of prescriptions comprised 7.4% of PBS-subsidised opioid dispensing before 1 June 2020, and 1.3% after the changes. Half-pack sizes comprised 8.4% of PBS-subsidised IR opioid medicine dispensing and 2.8% of all opioid medicines sold in the twelve months after the PBS changes. CONCLUSIONS: The introduction of new PBS rules for subsidised opioid medicines was followed by a decline in PBS-subsidised dispensing. Some people may have bypassed the new restrictions by switching to private prescriptions, but our findings suggest that opioid medicine use in Australia declined as a result of the new restrictions.

Expanding access to fracture liaison services in Australia for people with minimal trauma fractures: a system dynamics modelling study.

OBJECTIVES: To project how many minimal trauma fractures could be averted in Australia by expanding the number and changing the operational characteristics of fracture liaison services (FLS). STUDY DESIGN: System dynamics modelling. SETTING, PARTICIPANTS: People aged 50 years or more who present to hospitals with minimal trauma fractures, Australia, 2020-31. MAIN OUTCOME MEASURES: Numbers of all minimal trauma fractures and of hip fractures averted by increasing the FLS number (from 29 to 58 or 100), patient screening rate (from 30% to 60%), and capacity for accepting new patients (from 40 to 80 per service per month), and reducing the proportion of eligible patients who do not attend FLS (from 30% to 15%); cost per fracture averted. RESULTS: Our model projected a total of 2 441 320 minimal trauma fractures (258 680 hip fractures; 2 182 640 non-hip fractures) in people aged 50 years or older during 2020-31, including 1 211 646 second or later fractures. Increasing the FLS number to 100 averted a projected 5405 fractures (0.22%; $39 510 per fracture averted); doubling FLS capacity averted a projected 3674 fractures (0.15%; $35 835 per fracture averted). Our model projected that neither doubling the screening rate nor reducing by half the proportion of eligible patients who did not attend FLS alone would reduce the number of fractures. Increasing the FLS number to 100, the screening rate to 60%, and capacity to 80 new patients per service per month would together avert a projected 13 672 fractures (0.56%) at a cost of $42 828 per fracture averted. CONCLUSION: Our modelling indicates that increasing the number of hospital-based FLS and changing key operational characteristics would achieve only moderate reductions in the number of minimal trauma fractures among people aged 50 years or more, and the cost would be relatively high. Alternatives to specialist-led, hospital-based FLS should be explored.