The epidemiology of acute rheumatic fever and rheumatic heart disease in Queensland, 2017-2021: a population-level cohort study using linked administrative data.

Abstract

To determine the incidence and prevalence of acute rheumatic fever (ARF) and rheumatic heart disease (RHD) in Queensland during the period 2017-2021. Population-level retrospective cohort study using linked administrative data. Queensland residents aged younger than 45 years for ARF and younger than 55 years for RHD, identified from hospital, emergency department, death and Queensland RHD Register records for the period 1 January 2017 to 31 December 2021. Age-specific and age-standardised incidence and prevalence of ARF and RHD; and age-standardised incidence and prevalence ratios comparing Indigenous and non-Indigenous populations. 736 ARF episodes occurred among 670 people (395 [54%] female participants; 609 [83%] Indigenous). Of 4519 prevalent RHD cases aged < 55 years who were alive on 1 July 2021, 2655 (59%) were female, 2169 (48%) were Indigenous, and 1846 (41%) had severe disease. Previous ARF was recorded for 362 cases (8%). Among RHD cases aged younger than 25 years, 633 of 790 Indigenous individuals (80%) and 133 of 408 non-Indigenous individuals (33%) had RHD Register records. Indigenous age-standardised incidence (< 45 years) was 60.2 times higher (95% CI, 55.6-64.2) than non-Indigenous incidence for first ever ARF, 68.6 times higher (95% CI, 62.3-72.5) for total ARF, and 18.9 times higher (95% CI, 13.5-24.1) for RHD. For Indigenous people aged < 55 years, prevalence was 22.6 times higher (95% CI, 16.2-27.3) for ARF/RHD, 18.4 times higher (95% CI, 12.9-24.1) for RHD, and 12.1 times higher (95% CI, 8.3-15.9) for severe RHD. The overall burden of ARF and RHD was highest in northern Queensland health districts, whereas cases in the non-Indigenous population were concentrated in metropolitan south-east Queensland. The vast disparity in ARF and RHD burden between Indigenous and non-Indigenous Queenslanders indicates an urgent need for targeted, community-led prevention strategies. Under-representation of non-Indigenous youth in the RHD Register suggests improved clinical awareness and reporting is needed. Further investigation is warranted to inform equitable responses.