This study is undertaken to investigate the clinical metrics that effectively shed light on classifying types of diabetes among newly diagnosed diabetic patients with DK/DKA onset. It had demonstrated that C peptide, BMI, SBP and the presence of fatty liver can differentiate diabetes types of newly diagnosed diabetes with DK/DKA onset among children and adolescences. These metrics may assist in the clinical diagnosis and classification of diabetes, particularly in cases with overlapping characteristics.
Insulin deficiency is clinically evident through deteriorating glucose control and increased susceptibility to DK or DKA. In this study, similar to previous studies conducted among both adults and those with younger ages (12, 14, 17), the levels of C-peptide remained the most effective value for distinguishing between T1DM and T2DM during the entire duration of the 3-hour tests. However, it is worth noting that the cut-off point for C-peptide in this study was higher than the other studies, with a fasting level of 0.4 nmol/L and 2-h level of 2.0 nmol/L, whereas other studies among adults reported a fasting C-peptide levels of around 0.2 nmol/L and the 2-h level of approximately 0.5 nmol/L (18). Previously, there was evidence indicating that C-peptide levels at diagnosis were elevated with increasing age within each BMI group, highlighting the independent influence of age on C peptide (19–21). Thus, the discrepancy observed in our study may be attributed to the variations in age, as we included the youngest age of patients among all the studies. Besides, it is worth noting that C-peptide levels may initially rise during the diagnosis of pediatric T1DM, leading to a remission period, but subsequently decline rapidly in the first years after diagnosis. Consequently, employing a relatively high cut-off point for C peptide may enhance the sensitivity and specificity of classification. It is of great importance for pediatrics to pay more attention to those with moderately reserved C peptide.
Overweight has been proved to be associated with accelerated progression to T1DM in children and adolescents, in addition to its well-known association with T2DM. In this study, similar to previous studies focusing on adults with ketone-prone diabetes (22), BMI was proved to have significantly effective value of the classification between T1DM and T2DM among children and adolescents with DK/DKA at the onset, with the ranks of ROC analysis just after C-peptide. Furthermore, unlike most other studies(13, 14), our study had further included the rate of fatty liver as an evaluation of vesical fat rather than solely relying on subcutaneous fat (estimated by BMI), and it has been observed that the rateincidence of fatty liver does have a relatively high effective value for diabetes classification, particularly in relation to diabetes types in the context of obesity. This highlights the importance of accurately distinguishing between different types of diabetes, especially in the presence of childhood obesity, as it contributes to an overall increase in the population and in youths with diabetes.
The autoimmune antibodies, one of the emblematic metrics of T1DM, had been reported to be positive among several youths with T2DM (23). For ketone-prone diabetes, since it was discovered, the positive status of antibodies has been considered a major value metric for diabetes classification. However, in our study, even though there was a statistically significant difference in the positive rate of islet antibodies between T1DM and T2DM, the relatively small sample size may have contributed to the less effective value in the ROC analysis. Furthermore, as presented by previous studies, the islet of antibodies can be also negative in up to 20% of otherwise classical T1DM, particularly in children. The reported lower sensitivity or false negative rate may also contribute to the results.
A strength of the present study is the relatively large number of participants in both the confirmation and prognosis cohort, which had largely reduced the bias from patient selection and post-hoc analysis between comparison of clinical characteristics at the onset had been also made in the present study. In addition, the clinical characteristics employed in our study were those commonly utilized in clinical practice, enhancing the practicality of the obtained findings. The major limitation of our study was the retrospective collection of data from medical records rather than the prospective ones. Therefore, several major metrics, including the nature of islet antibodies, usually missing after 2-year follow-up, which might potentially bias the results. Furthermore, the majority of patients do not receive genetic testing, potentially resulting in the misdiagnosis of monogenic diabetes and skewing the outcomes. Another limitation of this study is that it is an investigation of DK/DKA clinical profiles from a single institution in the central province of China. To validate the effectiveness of prognostic metrics for classification, it is necessary to conduct further investigations with larger cohorts and, most importantly, prospective followed up studies.