Trends in HbA1c Change Among Youth Referred to a Pediatric Type 2 Diabetes Prevention Clinic

Abstract

Background: Pediatric type 2 diabetes (T2D) has increased in prevalence as childhood obesity rates climb. More youth are being referred to pediatric endocrinology due to the concern for developing T2D, yet prediction of which children will progress to overt T2D is challenging. We describe a single center experience with pediatric prediabetes referrals and trends in HbA1c change. Methods: Retrospective review of new patients seen at a Type 2 Diabetes Prevention (T2DP) Clinic July 2015 - December 2019. All children referred to T2DP Clinic have an elevated BMI and findings of insulin resistance/prediabetes/early T2D. They are evaluated by pediatric endocrinology providers and dieticians at each visit.The outcome of interest was categorical HbA1c change between patients’ initial and most recent T2DP Clinic visit. Only HbA1c measurements conducted at the study site were included to address inconsistencies in lab assays. HbA1c at the initial visit was categorized into 3 groups: 1) < 5.7%; 2) 5.7 to <6.5%; 3) 6.5% to <8.5%. Final HbA1c was categorized similarly with the option to progress to a 4th HbA1c group of ≥8.5%. Patients were categorized as progressors, regressors, or stable depending on change in group (e.g., group 1 --> group 2) between initial and most recent HbA1c. Comparisons between groups were made using ANOVA and Fisher’s exact tests. Results: Among 297 patients seen for an initial visit, mean BMI z-score was 2.3 and body fat percentage was 44%. High blood pressure occurred in 47%, high ALT in 24%, low HDL in 14%. Prevalence of initial HbA1c < 5.7%, 5.7 to < 6.5%, and 6.5% to < 8.5% was 46%, 42%, and 12%, respectively. One-third (31%) were prescribed metformin at their initial visit.Only 63 patients (21%) had 2 or more visits in the T2DP Clinic with study site HbA1c data available. Of those 63 patients, mean age at initial visit was 12.5 years, BMI z-score 2.0, and body fat 46%. Most patients were female (68%) with public insurance (70%). Race/ethnicity was 35% black, 29% white, 30% Hispanic. Mean time between initial and most recent HbA1c was 11.9 months. Assessment of categorical HbA1c change showed 14% of patients with progression (n=9), 65% stable (n=41), and 21% with regression (n=13). Female sex, ALT elevation, HbA1c, fasting glucose were found to be statistically different between the groups at baseline (p < 0.05). Age, race/ethnicity, BMI, body fat percentage, elevated blood pressure, lipid profile, 120-minute glucose on OGTT, and metformin use were not different between the groups. Conclusions. Only 14% of children who presented for follow up in our T2DP clinic demonstrated progression in HbA1c. Risk factors for those who progress include female sex and ALT elevation. Further development of predictive models to identify this high-risk population who will progress is necessary. Retaining consistent follow up in pediatric prediabetes clinics presents a challenge.