Among adults with adult-onset type 1 diabetes attending a tertiary diabetes clinic, DKA at diagnosis was associated with persistently less favourable glycaemic control during long-term follow-up, and exploratorily with a higher incidence of retinopathy.
About one in five adults with adult-onset T1D in this single-centre cohort presented with DKA at diagnosis.
The frequency of DKA at diagnosis increased markedly over time.
Adults presenting with DKA had persistently higher HbA1c during long-term follow-up than those without DKA.
When HbA1c data were aligned to the date of diabetes onset, the HbA1c difference between DKA and non-DKA groups was larger.
In exploratory analyses, DKA at diagnosis was associated with a higher incidence of retinopathy.
The association between DKA and retinopathy was attenuated after adjusting for mean HbA1c during follow-up.
The authors note that interpretation is limited by the study design.
This study looked at 517 adults diagnosed with type 1 diabetes at age 18 or older who were treated at one specialist diabetes centre in Italy between 2000 and 2025. About 22% of them were first diagnosed after developing diabetic ketoacidosis (DKA), a dangerous complication caused by a severe lack of insulin. The share of people diagnosed this way rose from about 13% in the early 2000s to about 35% after 2016. Over a median of about 9 years of follow-up, people who had DKA at diagnosis consistently had higher HbA1c (a measure of average blood sugar) than those who did not. The gap was about 0.37 percentage points after adjustment, and about 0.66 points when measured from the date diabetes began. In exploratory analyses, those who had DKA also developed eye damage (retinopathy) more often, with about a 61% higher rate. This link became weaker once average blood sugar during follow-up was taken into account, suggesting that poorer long-term glucose control may explain part of it. This research suggests that how a person's diabetes is first diagnosed may be linked to how their blood sugar control and eye health fare years later. However, the study was retrospective, took place at one specialist centre, and many people joined the cohort some time after diagnosis, so it cannot prove that DKA itself causes these outcomes. The findings may also not apply to all adults with type 1 diabetes.
Pollis R, Boscari F, Furlanetto D, Bittante C, Crepaldi M, Vedovato M, et al.. (2026). Diabetic Ketoacidosis at Diagnosis is Associated With Adverse Long-Term Glycaemic Trajectories and Retinopathy in Adult-Onset Type 1 Diabetes. A Single-Centre Retrospective Cohort Study.. Diabetes/metabolism research and reviews. https://doi.org/10.1002/dmrr.70249