Areal bone mineral density of the lumbar spine in 80 premature newborns: a prospective and longitudinal study.
BACKGROUND
Maximum bone mass accretion in the fetal skeleton is acquired during the third trimester of gestation, and may be compromised in premature newborns.


OBJECTIVE
To ascertain the incidence and evolution of osteopenia, a longitudinal study was performed to evaluate areal bone mineral density (aBMD) in the lumbar spine in premature newborns followed during the first 2 years of life.


METHODS
aBMD values were assessed in lumbar spine (L2-L4) by DEXA and expressed as grams hydroxyapatite/cm2 in 80 premature newborns, 41 boys and 39 girls, of gestational ages 24.5-35.7 weeks. aBMD values were evaluated at (mean+/-SD) 0.2+/-0.1 years (at discharge from the neonatal unit), 0.9+/-0.2 years and 2.0+/-0.5 years of postnatal age, and compared with those of age- and sex-matched full-term newborns with normal intrauterine and postnatal growth.


RESULTS
aBMD values recovered progressively from the first to the third evaluations, and were 0.139+/-0.06 g/cm2 (-2.4+/-1.4 SDS) at 0.2+/-0.1, 0.270+/-0.06 g/cm2 (-1.0+/-1.0 SDS) at 0.9+/-0.2 and 0.410 g/cm2 (-0.08+/-1.0 SDS) at 2.0+/-0.5 years.


CONCLUSIONS
Our data show a significant catch-up of aBMD, reaching values similar to those of full-term newborns at the age of 0.2+/-0.5 years, regardless of the gestational age at birth.
Pediatric Endocrinology Unit and Neonatology Unit, Hospital Materno-Infantil Vall d'Hebron, Barcelona, Spain. dyeste@vhebron.net
Diego
D
Yeste
Jordi
J
Almar
María
M
Clemente
Miguel
M
Gussinyé
Laura
L
Audí
Antonio
A
Carrascosa
D015502:Absorptiometry, Photon; D015519:Bone Density; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D008137:Longitudinal Studies; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging*; D008297:Male; D011446:Prospective Studies