{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T12:48:28Z","timestamp":1782910108835,"version":"3.54.5"},"reference-count":33,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T00:00:00Z","timestamp":1782864000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Metabolites"],"abstract":"<jats:p>Background and Objectives: GLP-1 receptor agonists (GLP-1 RAs) are effective weight-loss therapies, but data on body composition changes in pediatric obesity remain scarce. The primary objective was to evaluate the effects of GLP-1 RAs on body composition in children with obesity. Materials and Methods: We conducted a retrospective study of children with obesity evaluated at the National Institute for Mother and Child Health \u201cAlessandrescu-Rusescu\u201d, Bucharest, Romania, who initiated weekly injectable GLP-1 RA therapy (semaglutide) between January and December 2025. Patients were assessed at baseline and after a median follow-up of 5 months. Eight of ten participants with complete paired data were included in the final analysis; two were excluded because one was a non-responder with weight gain and suspected non-compliance, while one responder could not maintain the standing position for bioimpedance measurement. Bioimpedance analysis and anthropometry were performed at both visits. Paired data were analyzed using Wilcoxon signed-rank tests. Results: Eight children (4 boys, 4 girls; mean age 14.9 \u00b1 1.8 years) completed the study. Significant Body Mass Index (BMI) Z-score improvements were observed (CDC: \u22120.14, p = 0.012; WHO: \u22120.37, p = 0.012), with a median weight reduction of 4.75 kg (p = 0.036). While absolute muscle mass showed non-significant change (\u22121.3 kg, p = 0.362), predicted muscle mass percentage increased significantly (+1.9%, p = 0.012), suggesting selective fat loss. Fat-free mass percentage increased (+2.0%, p = 0.012) with reciprocal fat mass reduction (absolute: \u22123.85 kg, p = 0.017; percentage: \u22122.0%, p = 0.012). Fat-free mass index remained stable (\u22120.67 kg\/m2, p = 0.161). No serious adverse events occurred. Sensitivity analysis (n = 10) confirmed the robustness of the results, with improvements in BMI Z-scores remaining significant. Conclusions: In this preliminary pilot study, GLP-1 RA therapy in children with obesity was associated with significant improvements in BMI Z-scores and favorable shifts in body composition, consistent with selective fat loss and relative preservation of lean mass. These exploratory findings are hypothesis-generating and support the conduct of larger prospective controlled studies with body composition as a primary endpoint.<\/jats:p>","DOI":"10.3390\/metabo16070460","type":"journal-article","created":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T10:41:01Z","timestamp":1782902461000},"page":"460","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Body Composition Changes During GLP-1 Receptor Agonist Therapy in Pediatric Obesity: A Pilot Study"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1079-6028","authenticated-orcid":false,"given":"Bogdan Mihai","family":"Pascu","sequence":"first","affiliation":[{"name":"Pediatric Department, Faculty of Medicine, University of Medicine and Pharmacy \u201cCarol Davila\u201d, 030167 Bucharest, Romania"},{"name":"National Institute for Mother and Child Health \u201cAlessandrescu-Rusescu\u201d, 020395 Bucharest, Romania"},{"name":"Yuno Clinic, EASO COM Obesity Center, 020459 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-8117-3278","authenticated-orcid":false,"given":"Irina","family":"Bojoga","sequence":"additional","affiliation":[{"name":"Endocrinology and Diabetes Department, \u201cElias\u201d University Emergency Hospital, 011461 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5581-0041","authenticated-orcid":false,"given":"Anca","family":"B\u0103l\u0103nescu","sequence":"additional","affiliation":[{"name":"Pediatric Department, Faculty of Medicine, University of Medicine and Pharmacy \u201cCarol Davila\u201d, 030167 Bucharest, Romania"},{"name":"Yuno Clinic, EASO COM Obesity Center, 020459 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul Cristian","family":"B\u0103l\u0103nescu","sequence":"additional","affiliation":[{"name":"Pediatric Department, Faculty of Medicine, University of Medicine and Pharmacy \u201cCarol Davila\u201d, 030167 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ioan","family":"Gherghina","sequence":"additional","affiliation":[{"name":"Pediatric Department, Faculty of Medicine, University of Medicine and Pharmacy \u201cCarol Davila\u201d, 030167 Bucharest, Romania"},{"name":"National Institute for Mother and Child Health \u201cAlessandrescu-Rusescu\u201d, 020395 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,1]]},"reference":[{"key":"ref_1","unstructured":"(2026, February 18). 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