Response of serum carboxylated and undercarboxylated osteocalcin to risedronate monotherapy and combined therapy with vitamin K(2) in corticosteroid-treated patients: a pilot study.
OBJECTIVE
The aim of this study was to investigate the responses of serum osteocalcin (OC), undercarboxylated osteocalcin (ucOC) and N-terminal telopeptide of type I collagen (NTx) to corticosteroids, and to examine the effects of risedronate therapy with or without vitamin K(2) supplementation on bone metabolic markers in corticosteroid-treated patients.


METHODS
Sixteen patients on corticosteroid therapy for neuromuscular disorders were assigned randomly to 2 groups (A: risedronate monotherapy, n=8; B: combined risedronate and vitamin K(2) therapy, n=8) and treated for 1 year. Another 6 patients who received intravenous steroid pulse therapy were assigned to group C for investigation of the effects of corticosteroids on OC and ucOC 1 month after pulse therapy.


RESULTS
Serial measurements revealed that significant decreases of OC, ucOC and NTx persisted with a similar time course profile during 1 year of treatment in groups A and B, and between-group analysis failed to demonstrate any additional effects of vitamin K(2) on risedronate therapy. Intravenous steroid pulse therapy induced a transient depression of OC and ucOC within 1 week in group C.


CONCLUSIONS
These results indicate that serum concentrations of OC and ucOC become consistently low during corticosteroid administration despite risedronate therapy with or without vitamin K(2) supplementation, and the serum ucOC level may not be a reliable indicator of vitamin K status under corticosteroid administration.
Hozuki
Takayoshi
T
Department of Neurology, Sapporo Medical University School of Medicine.
Imai
Tomihiro
T
Tsuda
Emiko
E
Matsumura
Akihiro
A
Yamamoto
Daisuke
D
Toyoshima
Takanobu
T
Suzuki
Syuuichiro
S
Yamauchi
Rika
R
Hayashi
Takashi
T
Hisahara
Shin
S
Shimohama
Shun
S
D000305:Adrenal Cortex Hormones / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D015519:Bone Density / Q000187:drug effects; D050071:Bone Density Conservation Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001842:Bone and Bones / Q000378:metabolism; D024042:Collagen Type I / Q000097:blood; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D012968:Etidronic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009468:Neuromuscular Diseases / Q000097:blood* / Q000188:drug therapy*; D015675:Osteocalcin / Q000097:blood*; D010455:Peptides / Q000097:blood; D010865:Pilot Projects; D011239:Prednisolone / Q000627:therapeutic use; D000068296:Risedronic Acid; D016896:Treatment Outcome; D024482:Vitamin K 2 / Q000494:pharmacology / Q000627:therapeutic use*
D000305:Adrenal Cortex Hormones; D015415:Biomarkers; D050071:Bone Density Conservation Agents; D024042:Collagen Type I; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D015675:Osteocalcin; D024482:Vitamin K 2; D011239:Prednisolone; D000068296:Risedronic Acid; D012968:Etidronic Acid