Process evaluation of a maintenance pulmonary rehabilitation trial for people with chronic obstructive pulmonary disease.

BACKGROUND: The ComEx3 community-based extended maintenance pulmonary rehabilitation (PR) randomised controlled trial (RCT) aimed to determine the optimal strategy for maintaining the benefits of exercise for people with chronic obstructive pulmonary disease (COPD). We conducted a process evaluation of this RCT to determine if the trial was implemented per protocol, and to explore the barriers and facilitators of the trial, and mechanisms of impact. METHODS: This was a mixed methods study consisting of analysis of PR class records, study diaries and interviews of those involved in the trial. We developed a reporting framework from available literature and performed a content analysis. RESULTS: Eleven of the 12 participants in the intervention group attended ≥70% of available classes before the trial was terminated due to the COVID-19 pandemic. Analysis of the study diaries found that adherence to the home exercise program was higher in the intervention than the control group. Analyses of interviews (n = 21) highlighted the complexity of standardising the processes across multiple sites, but revealed behaviour change amongst class physiotherapists who were able to conform with the required processes. Facilitators of participation included the desire to improve function and quality of life, while barriers included illnesses and lack of motivation. Mechanisms of impact included confidence in exercising and benefits from the education sessions. CONCLUSIONS: The ComEx3 RCT was implemented as planned largely due to commitment by the research team and the desire by patients to improve their quality of life by attending a PR program that they are familiar with. Successful implementation of PR RCTs requires good organisational skills, clear and consistent trial documentation, broad understanding of participant needs while being conscious of challenges experienced by people with COPD, and dedication by everyone involved in the RCT. SO WHAT?: This article shows the importance of running a process evaluation alongside an RCT. Although this RCT did not progress to completion, this process evaluation which was guided by a robust framework, will provide guidance for future interventions in this area.

Medicine utilization studies in Australian individual-level dispensing data: A blinded, multi-center replicated analysis.

PURPOSE: Medicine dispensing data require extensive preparation when used for research and decisions during this process may lead to results that do not replicate between independent studies. We conducted an experiment to examine the impact of these decisions on results of a study measuring discontinuation, intensification, and switching in a cohort of patients initiating metformin. METHODS: Four Australian sites independently developed a HARmonized Protocol template to Enhance Reproducibility (HARPER) protocol and executed their analyses using the Australian Pharmaceutical Benefits Scheme 10% sample dataset. Each site calculated cohort size and demographics and measured treatment events including discontinuation, switch to another diabetes medicine, and intensification (addition of another diabetes medicine). Time to event and hazard ratios for associations between cohort characteristics and each event were also calculated. Concordance was assessed by measuring deviations from the calculated median of each value across the sites. RESULTS: Good agreement was found across sites for the number of initiators (median: 53 127, range: 51 848-55 273), gender (56.9% female, range: 56.8%-57.1%) and age group. Each site employed different methods for estimating days supply and used different operational definitions for the treatment events. Consequently, poor agreement was found for incidence of discontinuation (median 55%, range: 34%-67%), switching (median 3.5%, range: 1%-7%), intensification (median 8%, range: 5%-12%), time to event estimates and hazard ratios. CONCLUSIONS: Differences in analytical decisions when deriving exposure from dispensing data affect replicability. Detailed analytical protocols, such as HARPER, are critical for transparency of operational definitions and interpretations of key study parameters.

Evaluation of the awareness of Western Australian SunSmart campaigns between 2008 and 2022.

ISSUE ADDRESSED: It is unknown whether SunSmart health promotion campaigns in Western Australia are still effectively reaching their target audience of young people (under 45 years). This study examined trends over time in awareness, relevancy and believability of SunSmart advertisements and identified socio-demographic characteristics and risk factors associated with campaign awareness. METHOD: Linear regression and log-binomial modelling were undertaken using data from the annual SunSmart post-campaign evaluation surveys between 2008/2009 and 2021/2022. SunSmart campaigns were analysed and categorised into the following themes: (1) personal real-life stories; (2) daily activities/sun exposure leads to skin cancer; or (3) cartoon/animated. RESULTS: Between 2008 and 2022, there were declines in total awareness (74.2% to 20.4%), unprompted awareness (33.7% to 4.9%) and relevancy (89.5% to 54.8%) of SunSmart advertisements (representing annual percent decreases of 3.6%, 3.1% and 1.8%, respectively). However, believability remained high over time (>94% in each annual survey). Trends were inconsistent between the awareness of campaign themes and socio-demographic characteristics and risk factors. Several campaigns had greater awareness in their subsequent years, compared with the first campaign year. CONCLUSION: In more recent years, SunSmart advertisements and campaigns may not have reached their target audience. In addition to socio-demographic characteristics, particularly age, advertisement factors may also affect the awareness of specific campaigns. SO WHAT?: Given the changing advertising landscape and its rising costs, ongoing funding is pertinent to increase the reach of future SunSmart campaigns. Increasing advertisements on alternative platforms and designing campaigns which separately target adolescents and adults need to be considered.

Risk of Major Adverse Cardiovascular Event Following Incident Hospitalization for Acute Gout: A Western Australian Population-Level Linked Data Study.

BACKGROUND: Cardiovascular disease is the most common cause of death in people with gout. Acute inflammation, which is a characteristic of gout, may have a mechanistic role in major adverse cardiovascular events (MACEs). We aimed to examine the relationship between admissions to a hospital with acute gout and MACEs in a large population-based data set. METHODS: We extracted data from the Hospital Morbidity Data Collection and Death Registrations of the Western Australian Rheumatic Disease Epidemiology Registry. We identified patients admitted to hospital with incident acute gout and who had admissions or a death record because of MACEs. We compared the risk of MACEs during the postdischarge period (1-30 days after acute gout admission) and control period (365 days prior to admission and 365 days after the postdischarge period) using a self-controlled case-series (SCCS) design, which is a within-person design that controls for time-invariant patient-specific confounding. We performed conditional fixed-effects Poisson regression to obtain rate ratios (RRs). RESULTS: We identified 941 patients (average age: 76.4 years; SD: 12.6; 66.7% male) with an incident acute gout admission and documented MACEs during the control and/or postdischarge periods. Of the 941 patients, 898 (95%) experienced MACEs during the combined control period (730-day period) and 112 (12%) during the postdischarge period (30-day period). The rates of MACEs during the total control and postdischarge periods were 0.84 and 1.45 events per person-year, respectively. Regression analysis confirmed increased rate during the postdischarge period (RR: 1.67; 95% CI: 1.38-2.03) compared with the control period. Sensitivity analyses indicated that our results were robust in relation to known limitations of the SCCS design. CONCLUSION: We report an increased risk of MACEs in the first 30 days after an incident hospital admission with acute gout, suggesting a temporal association between acute inflammation and subsequent MACEs in patients with gout.

Priorities for building Australian workforce capacity to leverage population-based, routinely collected data: views from pharmacoepidemiology.

AIM: To explore perspectives of leaders in pharmacoepidemiology on building workforce capacity in the routinely collected data arena to enable researchers to generate evidence to support clinical and policy decision-making. METHODS: Semi-structured interviews were conducted between May and August 2018 with 13 leaders in pharmacoepidemiology in Australia. Discussion topics included training needs, workforce enablers, barriers and priorities for building capacity. The data was analysed using a content analysis approach. RESULTS: Leaders identified a range of knowledge and skills that are needed to work with routinely collected data and generate evidence to support clinical and policy decision making. Enablers identified included collaborations and promoting awareness to attract new people to work with this data type. Barriers included difficulty accessing data, lack of critical mass of human capital to build skill levels and funding issues. CONCLUSIONS: Building workforce capacity involves addressing identified enablers and barriers. Central to building workforce capacity is the harmonisation of Australia's data infrastructure, which can improve the way people work, learn, collaborate, share ideas and expand their professional network.

Validation of ICD-10-AM Coding for Myocardial Infarction Subtype in Hospitalisation Data.

BACKGROUND: International Classification of Disease (ICD) codes are central for identifying myocardial infarction (MI) in administrative hospitalisation data, however validation of MI subtype codes is limited. We measured the sensitivity and specificity of ICD-10-AM (Australian Modification) codes for ST-elevation MI (STEMI) and non-STEMI (NSTEMI). METHODS: A sample of MI admissions was obtained from a dataset containing all MI hospitalisations in Western Australia (WA) for 2003, 2008 and 2013. Clinical data were collected from hospital medical records (n=799 patients). Cases were classified by ICD-10-AM codes for STEMI, NSTEMI and unspecified MI, and compared to clinical classification from review of available electrocardiographs (ECGs) and cardiac biomarkers (n=660). Sensitivity and specificity for ICD-10-AM coding versus clinical classification was measured, stratified by calendar year of discharge. RESULTS: The majority of classifiable cases had MI recorded in the principal diagnosis field (STEMI n=293, 84.2%; NSTEMI n=202, 74.3%; unspecified MI n=20, 50.0%). Overall sensitivity of the ICD-10-AM STEMI code was 86.3% (95% CI 81.7-90.0%) and was higher when restricted to MI as a principal versus secondary diagnosis (88.8% vs 66.7%). Comparable values for NSTEMI were 66.7% (95% CI 61.5-71.6%), and 68.8% vs 61.4% respectively. Between 2003 and 2013, sensitivity for both MI subtypes increased: 80.2-89.5% for STEMI, and 51.2-73.8% for NSTEMI. Specificity was high for NSTEMI throughout (88.2% 95% CI 84.1-91.6%), although improving over time for STEMI (68.1-76.4%). CONCLUSIONS: The sensitivity and specificity of ICD-10-AM codes for MI subtypes in hospitalisation data are generally high, particularly for principal diagnosis cases. However, the temporal improvement in sensitivity in coding of MI subtypes, particularly NSTEMI, may necessitate modification to trend studies using administrative hospitalisation data.

The Hospital Frailty Risk Score Identifies Fewer Cases of Frailty in a Community-Based Cohort of Older Men Than the FRAIL Scale and Frailty Index.

OBJECTIVES: The recently developed Hospital Frailty Risk Score (HFRS) allows ascertainment of frailty from administrative data. We aimed to compare the HFRS against the widely used FRAIL Scale and Frailty Index. DESIGN: Population-based cohort study linked to Western Australian Hospital Morbidity Data Collection and Death Registrations. SETTING AND PARTICIPANTS: The Health in Men Study with frailty determined at Wave 2 (2001/2004), mortality in the 1-year period following Wave 2, and disability at Wave 3 (2008). Participants were 4228 community-based men aged ≥75 years, followed until Wave 3. MEASUREMENTS: We used multivariable regression to determine the association between each frailty measure and outcomes of length of stay (LOS), death, and disability. We also determined if the additional cases of frailty identified by one measure over the other was associated with these outcomes. RESULTS: Of 4228 men studied, the HFRS (n = 689) identified fewer men as frail than the FRAIL Scale (n = 1648) and Frailty Index (n = 1820). In the fully adjusted models, all 3 frailty measures were associated with longer LOS and mortality, whereas only the FRAIL Scale and Frailty Index were significantly associated with disability. The additional cases of frailty identified by the FRAIL Scale and Frailty Index had longer LOS and greater risks of death and disability. The fully adjusted hazard ratio for death among the additional cases of frailty identified by the FRAIL Scale (compared to being not frail on both HFRS and FRAIL Scale) was 2.14 (95% CI 1.48-3.08). CONCLUSIONS AND IMPLICATIONS: The HFRS is associated with adverse outcomes. However, it identified approximately 60% fewer men who were frail than the FRAIL Scale and Frailty Index, and the additional cases identified were also at high risks of adverse outcomes. Users of the HFRS should be aware of the differences with other frailty measures.

Optimal Measures for Primary Care Physician Encounters after Stroke and Association with Survival: A Data Linkage Study.

BACKGROUND AND PURPOSE: Primary care physicians (PCPs) provide ongoing management after stroke. However, little is known about how best to measure physician encounters with reference to longer term outcomes. We aimed to compare methods for measuring regularity and continuity of PCP encounters, based on survival following stroke using linked healthcare data. METHODS: Data from the Australian Stroke Clinical Registry (2010-2014) were linked with Australian Medicare claims from 2009 to 2016. Physician encounters were ascertained within 18 months of discharge for stroke. We calculated three separate measures of continuity of encounters (consistency of visits with primary physician) and three for regularity of encounters (distribution of service utilization over time). Indices were compared based on 1-year survival using multivariable Cox regression models. The best performing measures of regularity and continuity, based on model fit, were combined into a composite "optimal care" variable. RESULTS: Among 10,728 registrants (43% female, 69% aged ≥65 years), the median number of encounters was 17. The measures most associated with survival (hazard ratio [95% confidence interval], Akaike information criterion [AIC], and Bayesian information criterion [BIC]) were the Continuity of Care Index (COCI, as a measure of continuity; 0.88 [0.76-1.02], p = 0.099, AIC = 13,746, BIC = 13,855) and our persistence measure of regularity (encounter at least every 6 months; 0.80 [0.67-0.95], p = 0.011, AIC = 13,742, BIC = 13,852). Our composite measure, persistent plus COCI ≥80% (24% of registrants; 0.80 [0.68-0.94], p = 0.008, AIC = 13,742, BIC = 13,851), performed marginally better than our persistence measure alone. CONCLUSIONS: Our persistence measure of regularity or composite measure may be useful when measuring physician encounters following stroke.

Effect of frailty on initiation of statins following incident acute coronary syndromes in patients aged ≥75 years.

INTRODUCTION: Statin use for preventing recurrent acute coronary syndromes (ACS) is low in older people due to many clinical factors, including frailty. Using the recently developed hospital frailty risk score, which allows ascertainment of frailty from real-world data, we examined the association between frailty and initiation of statin treatment following incident ACS in patients aged ≥75 years. Our secondary aim was to determine whether non-initiation of statins was associated with more conservative treatment, defined as non-receipt of evidence-based medicines and/or coronary artery procedures. METHODS: We used person-linked hospital administrative and Pharmaceutical Benefits Scheme data to identify incident ACS admissions between 2005 and 2008 in Western Australia and prescription medicine use, respectively. Outcomes were receipt of any statin, high-dose statin, beta-blockers, renin-angiotensin system inhibitors (RASI), antiplatelets and coronary artery procedures within six months of the incident ACS and were analysed using multivariable generalised linear regression models. RESULTS: In 1,558 patients (52.4% female, mean age 82.6 years), initiation of any statin or high-dose statin decreased with increasing frailty. The adjusted risk ratios for any statin were 0.89 (95% CI: 0.82-0.97) and 0.67 (95% CI: 0.54-0.85) for the intermediate- and high-frailty categories compared with the low-frailty category, respectively. Compared with patients who received statins, those not receiving statins were less likely (p<0.001) to receive beta-blockers (80.8% vs 51.5%), RASI (86.9% vs 62.1%), antiplatelets (90.9% vs 65.1%) or a coronary artery procedure (65.9% vs 21.1%). CONCLUSIONS: Increasing frailty is inversely associated with initiation of statins and generally leads to a more conservative approach to treatment of older patients with ACS.

Incidence of Newly Registered Blindness From Age-Related Macular Degeneration in Australia Over a 21-Year Period: 1996-2016.

PURPOSE: Report the age-standardized annual incidence of blindness registration due to age-related macular degeneration (AMD) in Australia in patients aged 50 years and older. Frequencies of photodynamic therapy (PDT) and intravitreal therapy (IVT) were examined. DESIGN: Retrospective observational study. SETTING: Registry of the Association for the Blind of Western Australia with best-corrected visual acuity worse than 20/200 in the better-seeing eye. PARTICIPANTS: Registering as blind aged 50 years or over. MEASURES: Annual age-standardized incidence of blindness over 3 time periods: 1996-2001 (pre-PDT), 2002-2007 (PDT era) and 2008-2016 (IVT era). The rates of PDT and IVT usage were assessed. RESULTS: Age-standardized annual incidence of blindness rose during the PDT era, reaching 72.5 cases per 100,000 person-years in 2004. The incidence declined from 2007 onwards, reaching 8.2 cases per 100,000 person-years in 2016 (IVT era). The age at AMD blindness registration increased from 82.7 to 84.9 and 83.7 to 86.0 years from the PDT era to the IVT era in both male and females (P < 0.001) respectively. Over the same time period, PDT usage increased in 2002 and declined in 2006, whereas IVT usage increased from 2009 by 3745 per year. CONCLUSION: The increase in new blindness registrations due to AMD coincided with public funding of verteporfin for PDT, whereas the subsequent decline occurred when bevacizumab was used off-label and ranibizumab and aflibercept were publicly funded. An understanding of the effect of retinal therapy on public health measures may inform improvements in the allocation of limited resources.

Utility of the Hospital Frailty Risk Score Derived From Administrative Data and the Association With Stroke Outcomes.

Background and Purpose: Conditions associated with frailty are common in people experiencing stroke and may explain differences in outcomes. We assessed associations between a published, generic frailty risk score, derived from administrative data, and patient outcomes following stroke/transient ischemic attack; and its accuracy for stroke in predicting mortality compared with other measures of clinical status using coded data. Methods: Patient-level data from the Australian Stroke Clinical Registry (2009­2013) were linked with hospital admissions data. We used International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes with a 5-year look-back period to calculate the Hospital Frailty Risk Score (termed Frailty Score hereafter) and summarized results into 4 groups: no-risk (0), low-risk (1­5), intermediate-risk (5­15), and high-risk (>15). Multilevel models, accounting for hospital clustering, were used to assess associations between the Frailty Score and outcomes, including mortality (Cox regression) and readmissions up to 90 days, prolonged acute length of stay (>20 days; logistic regression), and health-related quality of life at 90 to 180 days (quantile regression). The performance of the Frailty Score was then compared with the Charlson and Elixhauser Indices using multiple tests (eg, C statistics) for predicting 30-day mortality. Models were adjusted for covariates including sociodemographics and stroke-related factors. Results: Among 15 468 adult patients, 15% died ≤90 days. The frailty scores were 9% no risk; 23% low, 45% intermediate, and 22% high. A 1-point increase in frailty (continuous variable) was associated with greater length of stay (ORadjusted, 1.05 [95% CI, 1.04 to 1.06), 90-day mortality (HRadjusted, 1.04 [95% CI, 1.03 to 1.05]), readmissions (ORadjusted, 1.02 [95% CI, 1.02 to 1.03]; and worse health-related quality of life (median difference, −0.010 [95% CI −0.012 to −0.010]). Adjusting for the Frailty Score provided a slightly better explanation of 30-day mortality (eg, larger C statistics) compared with other indices. Conclusions: Greater frailty was associated with worse outcomes following stroke/transient ischemic attack. The Frailty Score provides equivalent precision compared with the Charlson and Elixhauser indices for assessing risk-adjusted outcomes following stroke/transient ischemic attack.

Frailty, and not medicines with anticholinergic or sedative effects, predicts adverse outcomes in octogenarians admitted for myocardial infarction: Population-level study.

OBJECTIVE: To determine independent associations between the use of medicines with anticholinergic or sedative effects and frailty with outcomes of length of stay (LOS), coronary artery procedure performed and 30-day deaths in octogenarians admitted for a myocardial infarction (MI). METHODS: We quantified patient exposure to medicines with anticholinergic or sedative effects using the drug burden index (DBI) and frailty using the hospital frailty risk score (HFRS). We used multivariable regression methods to determine the association between DBI and HFRS with outcomes of LOS, coronary artery procedures performed and 30-day deaths. RESULTS: HFRS and not DBI score was significantly associated with receipt of coronary artery procedures (odds ratio [OR] 0.42; 95% CI 0.28-0.62 for high- versus low-risk groups) and 30-day deaths (OR 1.58; 95% CI 1.12-2.24 for high- versus low-risk groups). CONCLUSION: Frailty risk is a more important predictor of outcomes than DBI score for octogenarians with an MI.

Assuming one dose per day yields a similar estimate of medication adherence in patients with stroke: An exploratory analysis using linked registry data.

PURPOSE: Prescribed daily dose (PDD), the number of doses prescribed to be taken per day, is used to calculate medication adherence using pharmacy claims data. PDD can be substituted by (i) one dose per day (1DD), (ii) an estimate based on the 75th percentile of days taken by patients to refill a script (PDD75 ) or (iii) the World Health Organization's defined daily dose (DDD). We aimed to compare these approaches for estimating the duration covered by medications and whether this affects calculated 1-year adherence to antihypertensive medications post-stroke. METHODS: We conducted a retrospective review of prospective cohort data from the ongoing Australian Stroke Clinical Registry linked with pharmacy claims data. Adherence was calculated as the proportion of days covered (PDC) for 1DD, PDD75 and DDD. Differences were assessed using Wilcoxon rank-sum tests. RESULTS: Among 12 628 eligible patients with stroke, 10 057 (80%) were prescribed antihypertensive medications in the year after hospital discharge (78.2% aged ≥65 years, 45.2% female). Overall, the 75th percentile of patient time until next medication refill was 39 days. The greatest variations in dose regimens, estimated using person- and dose-level refill times, were for beta blockers (11.4% taking two tablets/day). There were comparable levels of adherence between 1DD and the PDD75 (median PDC 91.0% vs 91.2%; P = 0.70), but adherence was slightly higher using DDD (92.3%; both P < 0.001). However, this would represent a clinically nonsignificant difference. CONCLUSION: Adherence to antihypertensive medications shows similar estimates across standard measures of dosage in patients during the first year after an acute stroke.

Patterns of Use and Discontinuation of Secondary Prevention Medications After Stroke.

OBJECTIVE: To investigate whether certain patient, acute care, or primary care factors are associated with medication initiation and discontinuation in the community after stroke or TIA. METHODS: This is a retrospective cohort study using prospective data on adult patients with first-ever acute stroke/TIA from the Australian Stroke Clinical Registry (April 2010 to June 2014), linked with nationwide medication dispensing and Medicare claims data. Medication users were those with ≥1 dispensing in the year postdischarge. Discontinuation was assessed among medication users and defined as having no medication supply for ≥90 days in the year postdischarge. Multivariable competing risks regression, accounting for death during the observation period, was conducted to investigate factors associated with time to medication discontinuation. RESULTS: Among 17,980 registry patients with stroke/TIA, 91.4% were linked to administrative datasets. Of these, 9,817 adults with first-ever stroke/TIA were included (45.4% female, 47.6% aged ≥75 years, and 11.4% intracerebral hemorrhage). While most patients received secondary prevention medications (79.3% antihypertensive, 81.8% antithrombotic, and 82.7% lipid-lowering medication), between one-fifth and one-third discontinued treatment over the subsequent year postdischarge (20.9% antihypertensive, 34.1% antithrombotic, and 28.5% lipid-lowering medications). Prescription at hospital discharge (sub-hazard ratio [SHR] 0.70; 95% confidence interval [CI] 0.62-0.79), quarterly contact with a primary care physician (SHR 0.62; 95% CI 0.57-0.67), and prescription by a specialist physician (SHR 0.87; 95% CI 0.77-0.98) were all inversely associated with antihypertensive discontinuation. CONCLUSIONS: Patterns of use of secondary prevention medications after stroke/TIA are not optimal, with many survivors discontinuing treatment within 1 year postdischarge. Improving postdischarge care for patients with stroke/TIA is needed to minimize unwarranted discontinuation.

Maintaining quality of life in patients with chronic obstructive pulmonary disease (COPD) by extending the maintenance phase of community-based pulmonary rehabilitation: protocol for a randomised controlled trial (ComEx3 Study).

INTRODUCTION: Pulmonary rehabilitation is a core component of the treatment of people with chronic obstructive pulmonary disease (COPD); however, the benefits gained diminish in the ensuing months. The optimal strategy for maintaining the benefits is unclear with weekly supervised maintenance exercise programmes proposed as one strategy. However, the long-term future of maintenance programs is dependent on quality evidence. METHODS AND ANALYSIS: The ComEx3 randomised controlled trial will investigate the efficacy of extending a weekly supervised maintenance programme for an additional 6 months following an initial 10-week maintenance programme (intervention) by comparing with a control group who receive the same 10-week maintenance programme followed by 6 months of usual care. 120 participants with COPD will be recruited. Primary objective is to determine health-related quality of life over 12 months. Secondary objectives are to determine functional exercise capacity trajectory and to perform an economic evaluation of the intervention to the health system. Outcomes will be analysed for superiority according to intention-to-treat and per-protocol approaches. ETHICS AND DISSEMINATION: Approval has been received from the relevant ethics committees. Findings will be disseminated in peer-reviewed journals and conferences, targeting those involved in managing people with COPD as well as those who develop policies and guidelines. CLINICAL TRIAL REGISTRATION: ANZCTR 12618000933257.

Comparative trends in coronary heart disease subgroup hospitalisation rates in England and Australia.

BACKGROUND: Population-based coronary heart disease (CHD) studies have focused on myocardial infarction (MI) with limited data on trends across the spectrum of CHD. We investigated trends in hospitalisation rates for acute and chronic CHD subgroups in England and Australia from 1996 to 2013. METHODS: CHD hospitalisations for individuals aged 35-84 years were identified from electronic hospital data from 1996 to 2013 for England and Australia and from the Oxford Region and Western Australia. CHD subgroups identified were acute coronary syndromes (ACS) (MI and unstable angina) and chronic CHD (stable angina and 'other CHD'). We calculated age-standardised and age-specific rates and estimated annual changes (95% CI) from age-adjusted Poisson regression. RESULTS: From 1996 to 2013, there were 4.9 million CHD hospitalisations in England and 2.6 million in Australia (67% men). From 1996 to 2003, there was between-country variation in the direction of trends in ACS and chronic CHD hospitalisation rates (p<0.001). During 2004-2013, reductions in ACS hospitalisation rates were greater than for chronic CHD hospitalisation rates in both countries, with the largest subgroup declines in unstable angina (England: men: -7.1 %/year, 95% CI -7.2 to -7.0; women: -7.5 %/year, 95% CI -7.7 to -7.3; Australia: men: -8.5 %/year, 95% CI -8.6 to -8.4; women: -8.6 %/year, 95% CI -8.8 to -8.4). Other CHD rates increased in individuals aged 75-84 years in both countries. Chronic CHD comprised half of all CHD admissions, with the majority involving angiography or percutaneous coronary intervention. CONCLUSIONS: Since 2004, rates of all CHD subgroups have fallen, with greater declines in acute than chronic presentations. The slower declines and high proportion of chronic CHD admissions undergoing coronary procedures requires greater focus.

Exploring the effects of transfers and readmissions on trends in population counts of hospital admissions for coronary heart disease: a Western Australian data linkage study.

OBJECTIVES: To develop a method for categorising coronary heart disease (CHD) subtype in linked data accounting for different CHD diagnoses across records, and to compare hospital admission numbers and ratios of unlinked versus linked data for each CHD subtype over time, and across age groups and sex. DESIGN: Cohort study. DATA SOURCE: Person-linked hospital administrative data covering all admissions for CHD in Western Australia from 1988 to 2013. MAIN OUTCOME: Ratios of (1) unlinked admission counts to contiguous admission (CA) counts (accounting for transfers), and (2) 28-day episode counts (accounting for transfers and readmissions) to CA counts stratified by CHD subtype, sex and age group. RESULTS: In all CHD subtypes, the ratios changed in a linear or quadratic fashion over time and the coefficients of the trend term differed across CHD subtypes. Furthermore, for many CHD subtypes the ratios also differed by age group and sex. For example, in women aged 35-54 years, the ratio of unlinked to CA counts for non-ST elevation myocardial infarction admissions in 2000 was 1.10, and this increased in a linear fashion to 1.30 in 2013, representing an annual increase of 0.0148. CONCLUSION: The use of unlinked counts in epidemiological estimates of CHD hospitalisations overestimates CHD counts. The CA and 28-day episode counts are more aligned with epidemiological studies of CHD. The degree of overestimation of counts using only unlinked counts varies in a complex manner with CHD subtype, time, sex and age group, and it is not possible to apply a simple correction factor to counts obtained from unlinked data.

Identification of myocardial infarction type from electronic hospital data in England and Australia: a comparative data linkage study.

OBJECTIVE: To determine the utility of International Classification of Diseases (ICD) codes in investigating trends in ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI) using person-linked electronic hospitalisation data in England and Western Australia (WA). METHODS: All hospital admissions with myocardial infarction (MI) as the principal diagnosis were identified from 2000 to 2013 from both jurisdictions. Fourth-digit ICD-10 codes were used to delineate all MI types-STEMI, NSTEMI, unspecified and subsequent MI. The annual frequency of each MI type was calculated as a proportion of all MI admissions. For all MI and each MI type, age-standardised rates were calculated and age-adjusted Poisson regression models used to estimate annual percentage changes in rates. RESULTS: In 2000, STEMI accounted for 49% of all MI admissions in England and 59% in WA, decreasing to 35% and 25% respectively by 2013. Less than 10% of admissions were recorded as NSTEMI in England throughout the study period, whereas by 2013, 70% of admissions were NSTEMI in WA. Unspecified MI comprised 60% of all MI admissions in England by 2013, compared with <1% in WA. Trends in age-standardised rates differed for all MI (England, -2.7%/year; WA, +1.7%/year), underpinned by differing age-adjusted trends in NSTEMI (England, -6.1%/year; WA, +10.2%/year). CONCLUSION: Differences between the proportion and trends for MI types in English and WA data were observed. These were consistent with the coding standards in each country. This has important implications for using electronic hospital data for monitoring MI and identifying MI types for outcome studies.

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.

Clinical consultations and investigations before and after discontinuation of endocrine therapy in women with primary breast cancer.

OBJECTIVE: Although clinical trials recommend that women with hormone-dependent primary breast cancer remain on endocrine therapy for at least 5 years, up to 60% discontinue treatment early. We determined whether these women had consulted with clinicians or had investigations for cancer recurrence or metastasis around the time they discontinued endocrine therapy, and whether clinical contact continued after discontinuation. METHODS: We performed case-control and cohort studies of women from the 45 and Up Study who were diagnosed with invasive primary breast cancer between January 2003 and December 2008, and who had ≥12 months of anastrozole, exemestane, letrozole or tamoxifen subsequently dispensed. RESULTS: Women who consulted general practitioners and surgeons/oncologists, and women who had breast ultrasound/mammogram were just as likely to discontinue endocrine therapy within 30 days as those who did not consult these clinicians or have this investigation. In the 6 months after early discontinuation, women who discontinued endocrine therapy were less likely to consult general practitioners (adjusted risk ratio [RRadj] 0.80; 95% confidence interval [CI] 0.75, 0.86) and surgeons/oncologists (RRadj 0.62; 95% CI 0.54, 0.72) than those who remained on therapy. CONCLUSIONS: For most women, endocrine therapy discontinuation did not appear to follow consultation with doctors managing their breast cancer treatment or investigations for recurrence or metastasis. However, women who discontinued endocrine therapy were less likely to consult their general practitioner or surgeon/oncologist in the 6 months following discontinuation than those who remained on therapy. Of the clinician groups studied, general practitioners are best placed to engage and support women to continue pharmacotherapy. However, mechanisms are needed to prompt clinicians to do this at every visit.