BONE MINERAL
DENSITY BEFORE AND DURING TREATMENT WITH A LONG ACTING LHRH ANALOG IN CHILDREN WITH CENTRAL
PRECOCIOUS PUBERTY
Zosi P, Karakaidos D, Pizanias
S, Kanaris L, Tsilivakos D, Karis C
Pediatric Department
General hospital of Nikea "St. Panteleimon"
Piraeus, Greece
Bone
mineral density (BMD) and height increase during puberty, while body
composition changes markedly. In central precocious puberty the
hypothalamus‑pituitary‑gonadal axis is activated before the age of 8 in
girls and 9 in boys.Premature and
rapid skeletal maturation leads to decreased final compared to
target height.
Objective: In the present study, we evaluated
BMD and bone metabolism in 8 girls with central precocious puberty (CPP), before and during treatment
with a long acting L H R H analog (triptoreline).
Methods: In all girls
the appearance of pubertal signs commenced before the age of 8. All had a
history of the increased growth velocity, stage II (Tanner) breast
development or more and bone age, which was advanced more than one year
beyond chronological age at diagnosis. Patients were studied baseline and during treatment for
6 and 12 months. BMD was measured at the lumbar spine L2‑L4 level, using
dual energy x‑ray absorptiometry (DXA). Serum calcium, phosphate, alkaline
phosphatase and osteocalcin levels were measured. The variables were compared with 10 healthy age and sex
matched reference values of the same population and expressed as standard
deviation score.
Results: Mean lumbar
spine BMD SDS before treatment was significantly higher than healthy
controls. The lumbar spine BMD
SDS increased during the first 6 months of therapy and decreased between 6
months and 12 months of treatment (p<0,001). Alkaline phosphatase and osteocalcin levels had
decreased after 6 and 12 months but were not significantly different from
those of prepubertal controls.
Serum calcium and phosphate were normal and did not change during
treatment.
Conclusion: Patients with
CPP had normal BMD for chronological age but decreased for bone age after 1
year of treatment with an LHRH analog. Long‑term longitudinal studies are
needed to evaluate BMD after cessation of treatment.