Effect of carbamazepine and valproate on bone mineral density.
OBJECTIVE
To examine the effect of carbamazepine and valproate monotherapy on bone mineral density in children.


METHODS
Axial (second, third, and fourth lumbar vertebrae) and appendicular (distal third of radius) bone mineral density was measured by dual-energy x-ray absorptiometry in 27 healthy children and 26 children with uncomplicated idiopathic epilepsy treated with either carbamazepine (n = 13) or valproate (n = 13) for more than 18 months. Control subjects and patients were similar with respect to age, race (all white), and geographic area, and had no dietary restrictions, neurologic impairment, or physical handicaps.


RESULTS
Subjects were seizure-free for more than 6 months on a regimen of carbamazepine or valproate therapy, and had mean serum trough levels of 6.88 +/- 2 micrograms/ml and 72.04 +/- 45.6 micrograms/ml, respectively. Dietary calcium intake was similar in control and treated groups. After correction for gender and age, children treated with valproate had a 14% (p = 0.003) and 10% (p = 0.005) reduction in bone mineral density at the axial and appendicular sites, respectively. The reduction in bone mineral density increased with the duration of valproate therapy. Carbamazepine did not significantly reduce bone mineral density.


CONCLUSIONS
Valproate montherapy, but not carbamazepine therapy, significantly reduces axial and appendicular bone mineral density in children with idiopathic epilepsy and may increase their risk of osteoporotic fractures.
Sheth
R D
RD
Department of Pediatrics, West Virginia University Health Sciences Center, Morgantown 26506-9180, USA.
Wesolowski
C A
CA
Jacob
J C
JC
Penney
S
S
Hobbs
G R
GR
Riggs
J E
JE
Bodensteiner
J B
JB
D015502:Absorptiometry, Photon; D000293:Adolescent; D015519:Bone Density / Q000187:drug effects*; D002136:Calcium, Dietary / Q000008:administration & dosage; D002220:Carbamazepine / Q000009:adverse effects / Q000494:pharmacology* / Q000627:therapeutic use; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D004827:Epilepsy / Q000188:drug therapy; D005260:Female; D006801:Humans; D016014:Linear Models; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging; D008297:Male; D010024:Osteoporosis / Q000453:epidemiology; D011884:Radius / Q000000981:diagnostic imaging; D012307:Risk Factors; D014635:Valproic Acid / Q000009:adverse effects / Q000494:pharmacology* / Q000627:therapeutic use
D002136:Calcium, Dietary; D002220:Carbamazepine; D014635:Valproic Acid