Abstract Context Lumbar spine bone mineral density (BMD) rises sharply during puberty; earlier onset, as in central precocious puberty (CPP), may accelerate skeletal maturation and modify bone accrual. Objective To assess bone and body composition in girls with CPP/early puberty (EP), premature thelarche (PT) and prepubertal controls. Patients and Methods We analyzed 184 girls aged 5–9 years with suspected CPP/EP (108 CPP/EP, 76 PT) and 47 prepubertal controls (PC). DXA assessed L1–L4 and total body less head (TBLH) BMD, bone mineral content (BMC), and body composition. Derived measures included bone mineral apparent density (BMAD), trabecular bone score (TBS), android-gynoid fat ratio (A/G), fat mass index (FMI), and fat-free mass index (FFMI). Results Group CPP/EP showed greater height, BMI SDS, bone age (BA), FM, lean mass and FFMI than controls, with higher L1–L4 BMD (p0.001) and a trend for higher ΔBMD L1–L4–TBLH Z-score (p=0.07); L1-L4 BMAD Z-scores were similar. Versus Group PT, Group CPP/EP had higher Δheight-target height SDS (p=0.005), BA (p0.001), and lean mass (p=0.03); Group PT had higher A/G (p=0.02) and TBS (p=0.03). Within Group PT, girls with pubarche had higher height, BMI SDS, BA, FMI, A/G (p=0.02) and L1–L4 BMAD Z-scores (p=0.01). Conclusion Both CPP/EP and PT showed higher fat and lean mass than controls, with PT marked by greater central adiposity. Only overweight/obesity, and pubarche onset in PT, were associated with increased L1-L4 BMAD Z-scores. DXA provides additional insight into body composition and bone accrual in girls with early pubertal signs.
Fava et al. (Fri,) studied this question.