The effect of life-long thyroxine treatment and physical activity on bone mineral density in young adult women with congenital hypothyroidism.
OBJECTIVE
Normalization of plasma thyrotropin in T4-supplemented patients with thyroidal congenital hypothyroidism (CH) requires elevated plasma FT4-concentrations compared to patients with acquired thyroidal hypothyroidism. We investigated bone mineral density (BMD) in patients with CH.


METHODS
BMD was measured in 14 adult women with thyroidal CH and nine age-matched female controls.


RESULTS
There were no significant differences between patients and controls for femoral neck bone mineral content (BMC) (38.6 vs 37.6 g), BMD (0.98 vs 1.01 g/cm(2)), T-score (0.1 vs 0.3 SD) and z-score (0.1 vs 0.3 SD) and for spine BMC (63.1 vs 71.9 g). The differences in spine BMD (0.97 vs 1.09 g/cm(2)), T-score (-0.7 vs 0.4 SD) and z-score (-0.5 vs 0.6 SD) were significant (p = 0.025, p = 0.023, and p = 0.021, respectively).


CONCLUSIONS
Although BMD in patients with CH was slightly lower compared to controls, all scores were within the reference range. This does not support the hypothesis that the upwards shifted plasma FT4-concentrations in patients treated for CH have a deleterious effect on BMD.
Kempers
M J E
MJ
Department of Paediatric Endocrinology, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. m.j.kempers@amc.uva.nl
Vulsma
T
T
Wiedijk
B M
BM
de Vijlder
J J M
JJ
van Eck-Smit
B L F
BL
Verberne
H J
HJ
D015502:Absorptiometry, Photon; D000328:Adult; D015519:Bone Density / Q000187:drug effects*; D003409:Congenital Hypothyroidism / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D005260:Female; D005272:Femur Neck / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D008159:Lumbar Vertebrae / Q000187:drug effects* / Q000378:metabolism; D009043:Motor Activity / Q000187:drug effects* / Q000502:physiology; D013974:Thyroxine / Q000627:therapeutic use*
D013974:Thyroxine