Vitamin K Nutritional Status and Undercarboxylated Osteocalcin in Postmenopausal Osteoporotic Women Treated with Bisphosphonates

用双磷酸盐治疗的绝经后骨质疏松妇女的维生素K的营养状况和未羧化的骨钙素浓度

Jun Iwamoto ； Tetsuya Takada ； Yoshihiro Sato

《Asia Pacific Journal of Clinical Nutrition》 預刊文章 Pp. 8-14

https://doi.org/10.6133/apjcn.2014.23.2.15

摘要

Serum undercarboxylated osteocalcin (ucOC) is an index of vitamin K nutritional status in treatment-naive postmenopausal osteoporotic women. The purpose of the present study was to reveal the association between vitamin K nutritional status and serum ucOC concentrations in postmenopausal osteoporotic women taking bisphosphonates. Eighty-six postmenopausal women with osteoporosis (age range: 47-90 years) initiated bisphosphonate treatment. Vitamin K nutritional status was evaluated using a simple vitamin K-intake questionnaire and serum ucOC concentrations were measured after 6 months of treatment. The patients were divided into two groups according to the simple vitamin K-intake questionnaire score: a low vitamin K-intake (score ＜40) group (n=67) and a normal vitamin K-intake (score ≥40) group (n=19). There were no significant differences between the groups in baseline parameters including age, height, body weight, body mass index, serum alkaline phosphatase (ALP), urinary cross-linked N-terminal telopeptides of type I collagen (NTX), and changes in serum ALP and urinary NTX concentrations during the 6-month treatment period. However, the mean serum ucOC concentration after 6 months of treatment was significantly higher in the low vitamin K-intake group (2.79 ng/mL) than in the normal vitamin K-intake group (2.20 ng/mL). These results suggest that 78% of postmenopausal osteoporotic women treated with bisphosphonates may have vitamin K deficiency as indicated by low vitamin K-intake and high serum ucOC concentrations, despite having a similar reduction in bone turnover to women who have normal vitamin K-intake.

關鍵字

维生素K ； 绝经后妇女 ； 骨质疏松症 ； 未羧化的骨钙素 ； 营养

並列摘要

Serum undercarboxylated osteocalcin (ucOC) is an index of vitamin K nutritional status in treatment-naive postmenopausal osteoporotic women. The purpose of the present study was to reveal the association between vitamin K nutritional status and serum ucOC concentrations in postmenopausal osteoporotic women taking bisphosphonates. Eighty-six postmenopausal women with osteoporosis (age range: 47-90 years) initiated bisphosphonate treatment. Vitamin K nutritional status was evaluated using a simple vitamin K-intake questionnaire and serum ucOC concentrations were measured after 6 months of treatment. The patients were divided into two groups according to the simple vitamin K-intake questionnaire score: a low vitamin K-intake (score ＜40) group (n=67) and a normal vitamin K-intake (score ≥40) group (n=19). There were no significant differences between the groups in baseline parameters including age, height, body weight, body mass index, serum alkaline phosphatase (ALP), urinary cross-linked N-terminal telopeptides of type I collagen (NTX), and changes in serum ALP and urinary NTX concentrations during the 6-month treatment period. However, the mean serum ucOC concentration after 6 months of treatment was significantly higher in the low vitamin K-intake group (2.79 ng/mL) than in the normal vitamin K-intake group (2.20 ng/mL). These results suggest that 78% of postmenopausal osteoporotic women treated with bisphosphonates may have vitamin K deficiency as indicated by low vitamin K-intake and high serum ucOC concentrations, despite having a similar reduction in bone turnover to women who have normal vitamin K-intake.

並列關鍵字

vitamin K ； postmenopausal women ； osteoporosis ； undercarboxylated osteocalcin ； nutrition

參考文獻

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