Peak bone mineral accrual and age at menarche in adolescent girls: a 6-year longitudinal study.
OBJECTIVE
The greatest increase in bone mineral content occurs during adolescence. The amount of bone accrued may significantly affect bone mineral status in later life. We carried out a longitudinal investigation of the magnitude and timing of peak bone mineral content velocity (PBMCV) in relation to peak height velocity (PHV) and the age at menarche in a group of adolescent girls over a 6-year period.


METHODS
The 53 girls in this study are a subset of the 115 girls (initially 8 to 16 years) in a 6-year longitudinal study of bone mineral accretion. The ages at PBMCV and PHV were determined by using a cubic spline curve fitting procedure. Determinations were based on height (n = 12) and bone (n = 6) measurements over 6 years.


RESULTS
The timing of PBMCV and menarche were coincident, preceded approximately 1 year earlier by PHV. Correlation showed a negative relationship between age at menarche and both peak bone mineral accrual (r = -0.42, P < .002) and PHV (r = -0.45, P < .001).


CONCLUSIONS
This longitudinal study demonstrated the close association between age at PBMCV and age at menarche and confirmed the relationship between greater PBMCV and PHV in earlier, as compared with later, maturing girls.
McKay
H A
HA
College of Physical Education, University of Saskatchewan, Saskatoon, Canada.
Bailey
D A
DA
Mirwald
R L
RL
Davison
K S
KS
Faulkner
R A
RA
D000293:Adolescent; D001827:Body Height / Q000502:physiology; D015519:Bone Density / Q000502:physiology*; D002648:Child; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008572:Menarche / Q000502:physiology*; D012016:Reference Values