Suchergebnisse

IntroductionStroke is a leading cause of death and disability. Since 2012, our innovative national data linkage program, has enabled the successful linkage of data from the Australian Stroke Clinical Registry (AuSCR) with national and state-based datasets to investigate the continuum of stroke care and associated outcomes.
Objectives and ApproachUsing stroke as a case study, in this symposium we will describe the use of linked data to undertake clinical and economic evaluations and contribute new knowledge for policy and practice. We have undertaken a range of iterative and innovative projects linking the AuSCR (used now in >80 public hospitals across Australia with follow-up survey of patients between 90-180 days) with various administrative datasets. Linkages with the National Death Index, inpatient admissions and emergency presentations, Pharmaceutical Benefits Scheme (PBS), Medicare Benefits Schedule (MBS), Aged Care services; Ambulance Victoria, Australian Rehabilitation Outcomes Centre and general practice network datasets (POLAR) have been achieved.
ResultsThe symposium will provide case studies and results from four data linkage projects involving the AuSCR: 1) Stroke123 (NHMRC: #1034415), a study to investigate the impact of quality of acute care on admission/emergency presentations and survival; 2) PRECISE (NHMRC:#1141848), a study to evaluate models of primary care involving linkages with PBS/MBS, aged care services and admissions/emergency data; 3) AMBULANCE: a study to investigate how pre-hospital care affects acute stroke care involving linkages with the ambulance and admissions/emergency datasets; and 4) POLAR: a study to understand the long-term management of stroke involving linkages with primary health data.
Conclusion / ImplicationsThe National Stroke Data Linkage Program has been visionary and remains highly contemporary in the field of linked data. A unique feature of this program is the active participation of clinicians and policy-makers to ensure the evidence generated have direct benefits for accelerating change in practice and informing policy.

Background Administrative data are used extensively for research purposes, but there remains limited information on the quality of these data for identifying comorbidities related to stroke. Objective To compare the prevalence of comorbidities of stroke identified using International Classification Diseases, Australian Modification (ICD-10-AM) or Anatomical Therapeutic Chemical codes, with those from (i) self-reported data and (ii) published studies. Method The cohort included patients with stroke or transient ischaemic attack admitted to hospitals (2012–2016; Victoria and Queensland) in the Australian Stroke Clinical Registry (N = 26,111). Data were linked with hospital and pharmaceutical datasets to ascertain comorbidities using published algorithms. The sensitivity, specificity, and positive predictive value of these comorbidities were compared with survey responses from 623 patients (reference standard). An indirect comparison was also performed with clinical data from published stroke studies. Results The sensitivity of hospital ICD-10-AM data was poor for most comorbidities, except for diabetes (93.0%). Specificity was excellent for all comorbidities (87–96%), except for hypertension (70.5%). Compared to published stroke studies (3 clinical trials and 1 incidence study), the prevalence of diabetes and atrial fibrillation in our cohort was similar using ICD-10-AM codes, but lower for dyslipidaemia and anxiety/depression. Whereas in the pharmaceutical dispensing data, the sensitivity was excellent for dyslipidaemia (94%) and modest for anxiety/depression (77%). In the pharmaceutical data, specificity was modest for hypertension (78%) and anxiety or depression (76%), but specificity was poor for dyslipidaemia (19%) and heart disease (46%). Conclusion Variation was observed in the reporting of comorbidities of stroke in administrative data, and consideration of multiple sources of data may be necessary for research. Further work is needed to improve coding and clinical documentation for reporting of comorbidities in administrative data.

IntroductionDespite being recommended in clinical guidelines for secondary prevention of stroke, there are limited real-world data on outcomes associated with use of statins post-stroke.
Objectives and ApproachWe aimed to investigate the association between statin use and cardiovascular mortality post-stroke. We conducted a retrospective cohort study using prospectively collected data from the Australian Stroke Clinical Registry (2010-2014), linked with national medication dispensing and mortality data. We observed adult patients with first-ever ischaemic stroke or transient ischaemic attack (TIA) for 1-year following hospital discharge, or until their date of death, whichever occurred first. Statin use, defined as having an available statin dispensing, was assessed daily and treated as a time-varying exposure to account for patients who discontinued or reinitiated statins during follow-up. Multivariable, competing-risks regression, with non-cardiovascular death as the competing risk, was used to investigate the association between statin use and 1-year cardiovascular mortality.
ResultsAmong 8363 patients discharged following first-ever ischaemic stroke or TIA (48% aged ≥75 years, 45% female, 20% TIA, median length-of-stay 5 days), 945 died within 1 year, with 763 deaths being cardiovascular-related. The proportion of statin users was 65% at 90 days, 64% at 180 days, and 62% at 1 year. Groups least likely to be statin users at 1-year were women (odds ratio [OR]: 0.75; 95% CI: 0.67-0.85), patients aged <65 years (OR: 0.80; 95% CI: 0.69-0.92), and those discharged directly home (OR: 0.77; 95% CI: 0.67-0.88). Compared to non-use, use of statins was associated with a reduced risk of cardiovascular mortality within 1 year overall (sub-distribution hazard ratio [SHR]: 0.40; 95% CI: 0.34-0.46), and in sub-groups of patients with TIA, severe stroke, and advanced age.
Conclusion / Implications:Our preliminary data provide evidence of survival benefits associated with post-stroke statin use. Interventions to improve medication adherence may assist in reducing post-stroke mortality.

ObjectivesData linkage can provide sufficient breadth and size of data, to draw reliable estimates of effectiveness, at a population level using real-world data. We compared differences in survival and hospital presentations following stroke or transient ischaemic attack (TIA), based on whether a Medicare funded chronic disease management plan was claimed.
ApproachA population-based, comparative effectiveness study of Victorian and Queensland Australian Stroke Clinical Registrants (January 2012-June 2015), using the emulated target trial approach, was performed. Chronic disease management items were identified from Medicare claims in the 6-18 months post-stroke (exposure period). Data on covariates for model adjustment were obtained from hospital, pharmacy and aged care datasets. Outcomes at 19-30 months post-stroke were determined using the national death registry and state hospital data. Cox regression, adjusted using propensity score methods with inverse probability treatment weights was used to determine the effect of receipt of chronic disease management claims on outcomes.
ResultsOf 28,775 AuSCR registrants, 27,435 (95.3%) were linked across the Medicare, pharmacy and hospital datasets. Following exclusions, 11,574 registrants from 42 hospitals (42% female, median age 70 years, 27% TIA) were eligible for the study. Overall, 45% of participants received chronic disease management during the exposure period. After propensity score weighting, there was excellent balance between groups across 35 baseline variables (standardised differences <0.1). Receipt of chronic disease management (vs non-receipt) was associated with a 30% reduced hazard of death (adjusted Hazard Ratio [aHR]: 0.70, 95%CI: 0.57, 0.87) but a 17% increase in hospital presentations (aHR: 1.17, 95%CI: 1.12, 1.23). Variation was observed between planned (aHR: 1.21, 95%CI: 1.10, 1.33) and unplanned (aHR: 1.15, 95%CI: 1.07, 1.23) presentations.
ConclusionWe provide an evaluation of the effectiveness of Medicare funded chronic disease management within "real world" healthcare provision, thereby demonstrating the value of linked population data in health services research. Further work is underway to examine causal mechanisms.

IntroductionTo prevent further vascular events, prescribing of multiple classes of medications (antihypertensive, antithrombotic and lipid-lowering) is recommended in national clinical guidelines following ischaemic stroke.
Objectives and ApproachUsing real-world data, we determined the association between optimal combination pharmacotherapy (supply of all three classes, "optimal pharmacotherapy") and survival after stroke. We linked a cohort of patients with first-ever ischaemic stroke from the Australian Stroke Clinical Registry (2010-2014) with national pharmaceutical dispensing and national mortality data. Cox regression was used to determine associations between pharmacotherapy in the first 30 days of stroke with 1-year (from day 31 to 395) all-cause mortality. All analyses were adjusted for socio-demographic (age, sex) and clinical characteristics (stroke severity, discharge destination).
ResultsAmong 6684 patients discharged following first-ever ischaemic stroke (median length-of-stay 5 days), 6466 patients who survived to 30 days were included (44% female, median age 74 years). During the first 30 days from discharge, 71.4% received ≥1 medication class, and 32.9% (n=2125) received optimal pharmacotherapy. Patients with optimal pharmacotherapy were older (≥75 years 50.3% vs <75 years 44.5%; p<0.001), discharged directly home (home 58.5% vs other 40.3%; p<0.001) and experienced a less severe stroke (able to walk on admission 46.9% vs 36.4%; p<0.001), than those without optimal pharmacotherapy. Between day 31 and 395, there were 667 deaths; 530 related to cardiovascular disease. Compared to no medication, treatment with two medications was associated with a 42% lower risk of death (hazard ratio [HR]: 0.58; 95%CI: 0.45-0.73); and optimal pharmacotherapy had a 62% lower risk of death (HR: 0.38; 95% CI: 0.31-0.47). Survival was similar between those with one or no medication.
Conclusion / ImplicationsPatients with ischaemic stroke who received optimal pharmacotherapy within 30-days of admission had greater one-year-survival. Further research is required to understand reasons for sub-optimal pharmacotherapy in these patients.

ObjectiveTo determine the effectiveness of government policies supporting coordinated multidisciplinary primary care (MDC) in improving long-term survival following stroke or Transient Ischaemic Attack (TIA).
ApproachWe used the target trial framework for observational data to assess the average population effect of primary care MDC policies. The cohort comprised patients from the Australian Stroke Clinical Registry (January 2012-June 2015) linked with (i) Australian Medicare claims to define exposures (MDC claims in the 6-18 months post-stroke); (ii) hospital, pharmaceutical and aged care datasets for additional covariates; (iii) National Death Registry for survival outcomes (19-30 months post-stroke). Level of impairment was classified by latent class analysis using EQ-5D-3L questionnaire data obtained 90-180 days post-stroke. Multilevel survival analysis with inverse probability treatment weights was applied.
ResultsAmong 7,255 people with stroke (42% female, median age 71 years, 24% TIA, level of impairment: 39% minimal, 32% moderate, 29% severe), 29% had a Medicare claim for MDC (23% minimal, 31% moderate, 39% severe). Mortality was reduced in those receiving a claim (vs non-receipt) in the minimal (adjusted Hazard Ratio (aHR): 0.50, 95%CI:0.27, 0.91) and severe (aHR: 0.65, 95%CI:0.46, 0.91) impairment groups, but not the moderate impairment group (aHR: 1.31, 95%CI:0.86, 1.99). Group differences in allied health services claimed during MDC were observed: secondary prevention (14% minimal vs 10% severe impairment), rehabilitation (21% minimal vs 25% severe impairment).
ImplicationsDrawing causal inferences from linked observational data demonstrated the population effectiveness of primary care MDC policies, in improving survival following stroke/TIA, with variation by impairment class.