972-P: Trends in Rehospitalisation Rates for Myocardial Infarction, Heart Failure, and Stroke in People with and without Diabetes in Australia from 2012-2018

Abstract

Contemporary estimates of readmission rates and trends over time following cardiovascular events are required to prioritise clinical care. We estimated the incidence of readmission for myocardial infarction (MI) and heart failure (HF) following an MI, and of readmission for stroke following a stroke, stratified by diabetes status. We included everyone who was discharged from a hospital following an MI or stroke between 1 July 2012 and 30 June 2017 in Victoria, Australia (n=102323). Individuals were followed from discharge following an MI until readmission for MI or HF, or followed from discharge after a stroke until readmission for stroke, censoring at death or 1 year of follow-up. The incidence (per 100 person-years) of readmission for MI decreased in both people with and without diabetes (from 28.9 [95% CI: 27.4, 30.5] to 27.0 [25.6, 28.5] and from 18.5 [17.8, 19.3] to 15.2 [14.5, 16.0] from 2012 to 2016 [years beginning 1 July] in people with and without diabetes, respectively), but the incidence of readmission for HF only improved in people without diabetes (from 23.4 [22.0, 24.9] to 22.5 [21.1, 23.9] and 4.5 [4.1, 4.9] to 3.2 [2.9, 3.5]), and the incidence of readmission for stroke did not change (from 11.0 [9.5, 12.9] to 10.6 [9.2, 12.2] and 10.3 [9.3, 11.3] to 11.2 [10.3, 12.2]). However, the incidence rate ratio for people with vs. without diabetes increased for readmission for MI and HF. The excess risk for readmission for MI and HF for people with diabetes persisted after adjustment for age, sex, socioeconomic status, polypharmacy, comorbidity, and the competing risk of death: with subhazard ratios of 1.32 (1.28, 1.37) for MI and 3.77 (3.57, 3.98) for HF. The effect of diabetes on readmission for MI, but not HF or stroke, was stronger for women than men. Thus, improvements in rates of readmission for MI and HF were greater in people without diabetes than people with diabetes, therefore the excess risk for people with diabetes worsened from 2012-2018. Disclosure J. I. Morton: None. J. Ilomaki: Consultant; Self; AstraZeneca, Research Support; Self; Amgen Inc., Research Support; Spouse/Partner; GlaxoSmithKline plc. S. J. Wood: None. D. J. Magliano: None. J. E. Shaw: Advisory Panel; Self; Eli Lilly and Company, Merck Sharp & Dohme Corp., Pfizer Inc., Research Support; Self; AstraZeneca, Speaker’s Bureau; Self; AstraZeneca, Eli Lilly and Company, Novo Nordisk. Funding Australian Government Research Training Program (to J.I.M.); Monash University (to J.I.M.)