A-396 Comparative Evaluation of Continuous Glucose Monitoring and Point-of-Care Testing in Hospitalized Pediatric Patients

Background Diabetes mellitus is a major global health problem, affecting over 500 million people worldwide and about 38 million in the United States. Continuous glucose monitoring (CGM) has transformed diabetes management by offering real-time glucose results through minimally invasive sensors, reducing the need for frequent fingersticks. CGMs have not yet been cleared by the FDA for inpatient use, but studies in adults have demonstrated the clinical utility of CGM in both outpatients and hospitalized patients. However, studies supporting the use of CGMs in hospitalized pediatric patients are limited. We aimed to evaluate the accuracy and clinical impact of CGM use in pediatric inpatients. We hypothesized that the clinical performance of CGM is comparable to Standard-of-Care (SOC) glucose testing, including Core laboratory and Point-of-Care (POC) glucose testing. Methods This retrospective study comprised 72 unique pediatric inpatients with dysglycemia presenting to the St. Louis Children’s Hospital from 1/01/2023 to 9/30/2024. We analyzed paired glucose concentrations measured by CGM and collected within 10 minutes then tested by SOC testing using core lab or point-of-care (POC) glucose methods. To evaluate CGM performance, we conducted a four-way comparison: (a) CGM vs. POC glucose, (b) CGM vs. lab glucose, (c) CGM vs. SOC (Lab glucose and POC combined), and (d) POC vs. lab glucose within the same patient population. Performance was assessed by calculating the mean absolute relative difference (%MARD) and determining the percentage of glucose values in acceptable zones using Clarke Error Grid analysis. We also assessed the performance of CGM and POC in the hypoglycemic range and the frequency with which CGM was confirmed by SOC when testing in the hypoglycemic or hyperglycemic range as recommended by guidelines. Cohen’s kappa was calculated using 70 mg/dL and 180 mg/dL as the threshold for hypoglycemic and hyperglycemic. Results 41 males (56.9%) and 31 females (43.1%) were included in the study, with a median age of 13.3 years (IQR: 7.2 to16.2). The median HbA1c at admission was 8.4% (IQR: 6.8 – 10.8), and the median BMI was 20.4 (IQR: 16.1 – 25.4). A total of 2,228 matched CGM and SOC glucose pairs were analyzed, yielding an overall MARD of 14.8%, with over 94% of values falling within the clinically acceptable Clarke Zones A and B. However, the MARD was 20.2% when the CGM result was <70 mg/dL with 38.6% of specimens exceeding the FDA threshold of +/- 15mg/dL and a bias of 1.38 mg/dL in POC values relative to CGM. The Cohen*s kappa coefficient for CGM and POC paired glucose concentrations was 0.66 (95% CI: 0.63 – 0.69). Notably, 125 (28.0%) CGM readings below 70 mg/dL were not rechecked within 30 minutes using SOC methods, and 1,473 (84.7%) readings above 200 mg/dL were not confirmed with SOC glucose tests Conclusion The performance of CGM for pediatric inpatients is clinically acceptable but has a MARD that exceeds acceptable thresholds at low glucose concentrations, implying a need to confirm low readings by SOC methods. We provide evidence for guidelines to enforce confirmatory testing for CGM values outside normal limits.