Aims/hypothesis We investigated the long-term impact of diabetic ketoacidosis (DKA) at onset on metabolic regulation and residual beta cell function in a Danish population with type 1 diabetes. Methods The study is based on data from DanDiabKids, a Danish national diabetes register for children. The register provides clinical and biochemical data on patients with type 1 diabetes diagnosed in 1996-2009 and then followed-up until 1 January 2012. Repeated-measurement models were used as statistical methods.Results The study population comprised 2,964 children <18 years. The prevalence of DKA at diagnosis was 17.9%. Of the total subjects, 8.3% had mild, 7.9% had moderate and 1.7% had severe DKA. DKA (moderate and severe) was associated with increased HbA 1c (%) levels (0.24; 95% CI 0.11, 0.36; p=0.0003) and increased insulin dose-adjusted HbA 1c (IDAA 1c , 0.51; 95% CI 0.31, 0.70; p<0.0001) during followup, after adjustment for covariates. Children without a family history of diabetes were more likely to present with DKA (19.2% vs 8.8%, p<0.0001); however, these children had a lower HbA 1c (%) level over time (−0.35; 95% CI −0.46, −0.24; p<0.0001). Continuous subcutaneous insulin infusion (CSII) was associated with a long-term reduction in HbA 1c , changing the effect of DKA, after adjustment for covariates (p<0.0001). Conclusions/interpretation DKA at diagnosis was associated with poor long-term metabolic regulation and residual beta cell function as assessed by HbA 1c and IDAA 1c, respectively; however, CSII treatment was associated with improvement in glycaemic regulation and residual beta cell function, changing the effect of DKA at onset in our population.

The reported differences in glycemic regulation between Nordic and non-Nordic type 1 diabetes children and adolescents in four Nordic countries are diminutive, but persist after accounting for treatment intensity.