Diabetic ketoacidosis at diagnosis of type 1 diabetes and glycemic control over time: The SEARCH for diabetes in youth study

Abstract

The diagnosis of type 1 diabetes (T1D) in youth is often associated with diabetic ketoacidosis (DKA). We aimed to evaluate if the presence of DKA at diagnosis of T1D is associated with less favorable hemoglobin A 1c (HbA1c) trajectories over time. The SEARCH for Diabetes in Youth study of 1396 youth aged <20 years with newly diagnosed T1D were followed for up to 13 [median 8 (IQR 6-9)] years post-diagnosis. Of these, 397 (28%) had DKA (bicarbonate level<15 mmol/l and/or pH<7.25 (venous) or <7.30 (arterial or capillary) or mention of DKA in medical records) at diabetes onset. Longitudinal HbA1c levels were measured at each follow-up visit (average number of HbA1c measures 3.4). A linear piecewise mixed effects model was used to analyze the effect of DKA status at diagnosis of T1D on long-term glycemic control, adjusting for age at diagnosis, diabetes duration at baseline, sex, race/ethnicity, household income, health insurance status, time-varying insulin regimen and glucose self-monitoring, study site, and baseline fasting C-peptide level. At baseline, HbA1c levels were significantly higher in youth with T1D diagnosed in DKA versus those who were not (9.9%±1.5% vs. 8.5%±1.4%, respectively). After the first year with diabetes, there was a significant difference in the rate of change in HbA1c levels by DKA status: HbA1c was 0.16% higher each year in youth with DKA compared to those without (interaction p-value<.0001), after adjusting for aforementioned covariates. DKA at T1D diagnosis is associated with worsening glycemic control over time, independent of demographic, socioeconomic and treatment-related factors and baseline fasting C-peptide.