Development and validation of algorithms to identify newly diagnosed type 1 and type 2 diabetes in pediatric population using electronic medical records and claims data.

PURPOSE: To develop and validate algorithms to classify diabetes type in newly diagnosed pediatric patients with DM. METHOD: Data from the United States Department of Defense health system were used to identify patients aged 10 to 18 years with incident DM. Two independent sets of 200 children were randomly sampled for algorithm development and validation. Algorithms were developed based on clinical insight, published literature, and quantitative approaches. The actual DM type was ascertained via chart review. Finally, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were evaluated. RESULTS: Among the 400 patients, mean age was 14.2 (±2.5 years), and 50% were female. The best performing algorithms were based on data available in claims. They consisted of several logical expressions based on one predictor or more, which classified patients by use of glucose-lowering drugs or testing, DM ICD-9 diagnosis codes, and comorbidities. The best performing T2DM and T1DM algorithms achieved 90% and 98% sensitivity, 95% and 95% specificity, 87% and 98% PPV, and 96% and 96% NPV, respectively. CONCLUSIONS: Our results suggest that claims algorithms can accurately identify newly diagnosed T1DM and T2DM pediatric patients, which can facilitate large database studies in children with T1DM and T2DM. However, external validation in other data sources is needed.

Celiac Autoimmunity Is Associated With Lower Blood Pressure and Renal Risk in Type 1 Diabetes.

Context: Though the long-term consequences of celiac disease (CD) in type 1 diabetes are unclear, CD has been associated with increased prevalence of end-stage renal disease (ESRD) independent of type 1 diabetes. Objective: We evaluated whether celiac autoimmunity is related to the cumulative incidence of microalbuminuria [albumin excretion rate (AER) 20 to 200 µg/min], macroalbuminuria (AER >200 µg/min), and ESRD. Design, Patients, and Methods: In the prospective follow-up of the Pittsburgh Epidemiology of Diabetes Complications study of childhood-onset type 1 diabetes, 618 participants were screened for tissue transglutaminase (tTG) antibodies with a clinical assay. Nephropathy outcomes were determined at 25 years of diabetes duration. Results: Overall, the 33 subjects (5.3%) with strongly positive tTG levels (≥3 times the upper limit of normal) or a reported clinical history of CD had lower baseline blood pressure and lipid values. At 25 years of diabetes duration, a lower cumulative incidence of macroalbuminuria in strongly positive subjects compared with those with negative serology (3.6% vs 30.0%; P = 0.003) remained significant after adjustment for age, HbA1c, lipid measures, and blood pressure (adjusted P = 0.004). No considerable differences between these subjects and tTG-negative groups were found for microalbuminuria (40.0% vs 57.1%) or ESRD (0 vs 4.1%). Conclusions: These findings show that strongly positive celiac autoimmunity status in individuals with childhood-onset type 1 diabetes is associated with lower baseline blood pressure and cholesterol measurements as well as lower macroalbuminuria risk after 25 years of type 1 diabetes duration with no increase in the risk of microalbuminuria or ESRD.