<p><strong>BACKGROUND: </strong>Prediabetes awareness in adults has been associated with improved weight management. Whether youth with prediabetes diagnosis experience similar improvements is unknown.</p>

<p><strong>OBJECTIVE: </strong>To investigate the association between prediabetes identification and body mass index trajectory in overweight and obese adolescents.</p>

<p><strong>SUBJECTS: </strong>Youth who were followed longitudinally in a large academic-affiliated primary care network and who were overweight/obese while 10-18 years old.</p>

<p><strong>METHODS: </strong>Retrospective cohort study. Subjects were categorized as "screened" if at least 1 hemoglobin A1c (HbA1c) result was available. Time series analysis was used to determine the difference in difference (DID) in body mass index Z-score (BMI-Z) slope before and after HbA1c between: 1) screened youth found to have prediabetes-range HbA1c (5.7-6.4%, 39-46 mmol/mol) versus normal HbA1c, and 2) screened versus age-matched unscreened obese youth.</p>

<p><strong>RESULTS: </strong>4,184 (55.6% female) screened subjects (median follow-up 9.7 years) were included. 637 (15.2%) had prediabetes-range HbA1c. Prediabetes was associated with a greater decrease in BMI-Z slope than normal HbA1c (DID: -0.023/year [95% CI: -0.042 to -0.004]). When compared to age-matched unscreened subjects (n=2,087), screened subjects (n=2,815) experienced a greater decrease in BMI-Z slope after HbA1c than unscreened subjects at a matched age (DID: -0.031/y [95% CI -0.042 to -0.021]).</p>

<p><strong>CONCLUSIONS: </strong>BMI-Z trajectory improved more among youth with prediabetes-range HbA1c but also stabilized in screened youth overall. Prospective studies are needed to identify provider- and patient-level drivers of this observation. This article is protected by copyright. All rights reserved.</p>