929-P: A Population-Based Study of Long-Term HbA1c Associated with Diabetic Ketoacidosis at Diagnosis of Type 1 Diabetes in Western Australian Children

Abstract

Background: In addition to the acute illness associated with DKA at diagnosis of T1D in children, there is some evidence of its association with poor long-term glycaemic outcomes, increasing risk of complications. With growing global interest in screening for pre-diabetes in children, long-term outcomes are an important consideration in terms of economic viability but there is limited high quality data. This population-based study helps to address this gap. Methods: All children <16 years presenting to Perth Children’s Hospital with new onset T1D 2000-2019 were included and followed up for ≤ 14 years. Moderate-severe DKA at diagnosis was defined as serum pH <7.2 or bicarb <15mmol/l in the presence of hyperglycaemia and ketosis. HbA1c was recorded at each clinic visit, ~3 monthly from diagnosis. A linear mixed model, adjusted for sex, diagnosis age, socioeconomic status and metro/regional area of residence, was used to examine long-term HbA1c associated with DKA at diagnosis at each year of duration. Results: The population-based cohort included 2063 patients and median [IQR] follow-up time was 5.4 [3.0-8.4] years. The incidence of DKA at diagnosis was 25%. Patients presenting with DKA had a higher mean HbA1c at diagnosis as expected but from 2 to 7 years post-diagnosis there was no difference between the two groups. Mean HbA1c of patients presenting with DKA increased relative to the remainder from 7 years. The only comparable study, conducted in Colorado in 2017, reported an immediate and sustained relationship between DKA severity at onset and HbA1c over 15 years. Conclusion: The difference in findings for similar cohorts in Australia and the US raises questions regarding the variables that influence long-term glycaemic outcomes in children diagnosed with T1D. Further studies are required to explore the association between DKA at diagnosis and HbA1c over time and to understand the importance of sociodemographic, physiological and other factors. Disclosure H. Clapin: None. G. J. Smith: None. S. Vijayanand: None. T. Jones: None. E. A. Davis: None. A. Haynes: None.