Premature pubarche in Prader-Willi syndrome: Risk factors and consequences.

Objectives: Children with Prader-Willi Syndrome (PWS) may develop premature pubarche (PP). We investigated the frequency of PP, and its potential precursors and sequelae, in PWS.

Design, Patients And Measurements: A chart review of children with PWS treated at our institution between 1990 and 2021 was performed. PP was defined as Tanner stage 2 (TS2) pubic hair in girls <8 and boys <9 years old. Demographic, anthropometric, and laboratory data were collected to assess predisposing factors and consequences of PP in comparison to patients with PWS who had normal pubarche (NP).

Results: Analysis included 43 children with PWS, 23 (53.5%) with PP and 20 (46.5%) with NP. Median age at pubarche was 7.0 years in PP group and 10.0 years in NP group. Age at pubarche was not correlated with age of recombinant human growth hormone (rhGH) initiation, body mass index (BMI) z-score, or homeostasis model assessment of insulin resistance (HOMA-IR) at pubarche. BMI z-score at pubarche was modestly correlated with degree of pubarchal BA advancement (p = 0.033). Those with PP were more likely to have a lower high-density lipoprotein (HDL) (1.05 mmol/L vs. 1.41 mmol/L in the NP group, p = 0.041). The difference between target and final height did not differ between groups (p = 0.507).

Conclusion: PP is common in PWS but does not compromise final height in comparison to the NP group. Obesity and insulin resistance were not associated with PP in children with PWS, contrary to what has been seen in obese children without PWS.