Epidemiology

Objectives To examine the epidemiology of stroke and transient ischaemic attack (TIA), and quality of care provided to Aboriginal and Torres Strait Islander (‘Indigenous’) patients presenting to emergency medical services (EMSs) with stroke or TIA.DesignRetrospective population-based data linkage study.Setting, ParticipantsVictoria, Australia. Patients aged ≥ 18 years with hospital-confirmed stroke or TIA who presented to EMSs between 1 January 2015 and 30 June 2019 and were successfully linked with hospital or mortality datasets.Main Outcome MeasuresThirty- and 90-day mortality, crude and age-standardised incidence rates, EMS quality of care.ResultsAmong 32,163 patients, 287 (0.9%) were Indigenous. Indigenous patients were younger than non-Indigenous patients (median age, 62 vs. 77 years, p < 0.001). Age-standardised incidence of EMS attendance was higher within the Indigenous population (343 vs. 144 per 100,000 person-years; incidence rate ratio, 2.383 [95% confidence interval (CI), 2.084–2.711]). Rates of call-taker identification of stroke or TIA and hospital diagnoses were comparable; however, Indigenous patients were less likely to receive a stroke assessment from paramedics (166/285 [58.2%] vs. 21,271/31,605 [67.3%]; p = 0.001) and more frequently taken to stroke-capable hospitals (257/275 [93.5%] vs. 27,371/30,647 [89.3%]; p = 0.027), but less frequently taken to endovascular thrombectomy-capable hospitals (67/275 [24.4%] vs. 10,015/30,647 [32.7%]; p = 0.003). Adjusted mortality was similar between groups (30 days: hazard ratio, 0.814 [95% CI, 0.518–1.279]; 90 days: hazard ratio, 0.805 [95% CI, 0.534–1.214]). However, age-standardised incidence of 90-day mortality was higher within the Indigenous population (39 vs. 24 per 100,000 person-years; incidence rate ratio, 1.621 [95% CI, 1.031–2.398]). Indigenous patients also more often recontacted EMSs for any reason within 90 days (subdistribution hazard ratio, 1.548 [95% CI, 1.194–2.007]).ConclusionsThe age-standardised incidence of EMS attendance for stroke in the Indigenous population was more than double that for the non-Indigenous population. Although there was no difference in stroke identification at the time of the emergency call, Indigenous patients were less likely to be evaluated by paramedics for stroke.

Candice Menezes, Ziad Nehme, Luke J. Burchill, Tegwyn McManamny, Angela Dos Santos, Michelle Crilly, Luke P. Dawson, Benjamin Clissold, David Anderson, Emily Nehme

Generation Victoria (GenV), Australia's largest population-representative cohort study, has established a scalable and pragmatic approach to biobanking. This article describes the guiding principles used to overcome previous obstacles and build this unique population-representative mega-cohort birth biobank. By prospectively banking residual clinical biosamples and strategically collecting additional biosamples for targeted multi-omics analyses, GenV reduces participant burden while enabling comprehensive biological research. Designed for long-term follow-up from birth through childhood and beyond, the GenV biobank represents an openly accessible resource, available to the Australian biomedical researcher community through established data and biospecimen access pathways.

Katherine Lange, Kim L. Powell, Yeukai Mangwiro, Tony Frugier, Donna T. Geddes, Melissa Wake, Richard Saffery

Objectives To characterise osteoporosis medicine prescribing patterns following low-trauma fractures and identify predictors of early treatment initiation.Study TypeRetrospective population-based cohort study.SettingNew South Wales, Australia, using statewide linked administrative health data.ParticipantsAdults aged ≥ 50 years with an incident low-trauma fracture between January 2011 and June 2019.Main Outcome MeasuresPrimary outcomes were osteoporosis treatment prescribing patterns and timing of initiation after incident fracture over 3 years, categorised as early (within 12 months), late (within 1–3 years) or no initiation. Secondary analyses examined predictors of time to treatment initiation within 12 months using Fine–Gray competing-risk regression.ResultsAmong 132,268 individuals with incident fractures, 63.7% (84,222) were female. Overall, 29,802 (22.5%) initiated osteoporosis medicine, whereas 102,466 (77.5%) remained untreated. Among females (mean [standard deviation] age, 77.7 [10.1] years), 20.1% initiated therapy within 12 months, 7.0% within 1–3 years, and 72.9% remained untreated. Among males (mean [standard deviation] age, 77.2 [10.0] years), the corresponding proportions were 10.8%, 3.7% and 85.6%. After accounting for the competing risk of death, treatment initiation was more likely with non-distal fractures, older age, polypharmacy, prior steroid use, prior dual-energy x-ray absorptiometry and later fracture year, and less likely with greater comorbidity, rural or regional residence and prior hospitalisation for falls. The strongest associations were for hip or vertebral fracture (subdistribution hazard ratio range, 1.90–3.03) and high comorbidity burden (subdistribution hazard ratio range, 0.72–0.75). Almost one in four late initiators had a refracture before starting treatment. Denosumab rapidly replaced oral bisphosphonates as the dominant therapy over time.ConclusionMore than three-quarters of individuals remain untreated after fracture, highlighting persistent and substantial gaps in secondary fracture prevention. Treatment initiation is strongly associated with fracture site and multimorbidity burden, and initiation rates are lower in males. Increasing reliance on denosumab underscores the need for careful long-term treatment planning and strategies.

Mike Lin, Huy Nguyen, Thach Tran, Robert D. Blank, Dana Bliuc, Jacqueline R. Center

The significant ARF and RHD burden among Indigenous Queenslanders, and vast disparity with non-Indigenous populations, calls for an urgent whole-of-government response to redress. Analysis of linked administrative data can inform place-based ARF and RHD strategies

Carl J Francia (Saibai Koedal awgadhalayg, Guda Maluylgal Nation) · Leanne M Johnston · Ingrid Stacey · Robert N Justo · John F Fraser · Judith M Katzenellenbogen