Vitamin D deficiency and whole-body and femur bone mass relative to weight in healthy newborns.
BACKGROUND
Vitamin D is required for normal bone growth and mineralization. We sought to determine whether vitamin D deficiency at birth is associated with bone mineral content (BMC) of Canadian infants.


METHODS
We measured plasma 25-hydroxyvitamin D [25(OH)D] as an indicator of vitamin D status in 50 healthy mothers and their newborn term infants. In the infants, anthropometry and lumbar, femur and whole-body BMC were measured within 15 days of delivery. Mothers completed a 24-hour recall and 3-day food and supplement record. We categorized the vitamin D status of mothers and infants as deficient or adequate and then compared infant bone mass in these groups using nonpaired t tests. Maternal and infant variables known to be related to bone mass were tested for their relation to BMC using backward stepwise regression analysis.


RESULTS
Twenty-three (46%) of the mothers and 18 (36%) of the infants had a plasma 25(OH)D concentration consistent with deficiency. Infants who were vitamin D deficient were larger at birth and follow-up. Absolute lumbar spine, femur and whole-body BMC were not different between infants with adequate vitamin D and those who were deficient, despite larger body size in the latter group. In the regression analysis, higher whole-body BMC was associated with greater gestational age and weight at birth as well as higher infant plasma 25(OH)D.


CONCLUSIONS
A high rate of vitamin D deficiency was observed among women and their newborn infants. Among infants, vitamin D deficiency was associated with greater weight and length but lower bone mass relative to body weight. Whether a return to normal vitamin D status, achieved through supplements or fortified infant formula, can reset the trajectory for acquisition of BMC requires investigation.
Weiler
Hope
H
Department of Human Nutritional Sciences, University of Manitoba, Winnipeg, Man. hweiler@cc.umanitoba.ca
Fitzpatrick-Wong
Shirley
S
Veitch
Rebecca
R
Kovacs
Heather
H
Schellenberg
Jeannine
J
McCloy
Ursula
U
Yuen
Chui Kin
CK
D000328:Adult; D001827:Body Height; D001835:Body Weight; D015519:Bone Density; D019587:Dietary Supplements; D005260:Female; D005269:Femur / Q000502:physiology; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D016014:Linear Models; D008297:Male; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000503:physiopathology*
D014807:Vitamin D; C104450:25-hydroxyvitamin D