Je SH, et al. • Vitamin K Supplement and BMD, UcOC Changes 385 subjects screened for participation 83 evaluated for baseline lab tests 78 subjects underwent randomization 302 subjects did not meet inclusion criteria 5 subjects withdrew before randomization 40 assigned to control group Vitamin D + Calcium supplement 38 assigned to vitamin K group Vitamin K + Vitamin D + Calcium supplement 13 dropped out (32.5%) 20 dropped out (53%) 40 included in the intention to treat group 27 completed the intervention 38 included in the intention to treat group 18 completed the intervention Fig. 1. Screening, randomization and follow up for study subjects. ic at Cha Hospital in Seoul from January-May 2010 were recruit- ed (n = 385) (Fig. 1). Of those screened, 103 women were exclud- ed for taking vitamin K, anti-lipid medications, hormone replace- ment therapy, or medications influencing bone metabolism as- pects such as bisphosphonate, calcitonin, steroids, phenytoin, carbamazepine, rifampicin, heparin, and warfarin. As well, 199 women with diabetes, hypertension, body mass index (BMI) > 30 kg/m2, or metabolic bone diseases were excluded. Five other subjects withdrew before randomization for personal reasons. The remaining 78 women were randomly assigned to either the treatment group (vitamin K, n = 40) or a control group (n = 38). For 6 months, the treatment group received 15 mg of vitamin K2 (menatetrenone) three times a day after every meal, combina- tion form containing 400 IU of active vitamin D3 once a day, and 315 mg of calcium carbonate twice daily. During the same peri- od, the control group received 400 IU of vitamin D and 315 mg of calcium twice daily. During the course of the study, 33 wom- en dropped out due to relocation or loss to follow-up. Forty five women completed the study. Fasting blood (10 hr of fasting in the morning) was collected at baseline and at months 3 and 6. Total cholesterol, triglyceride and high density lipoprotein (HDL) cholesterol were measured by an enzymatic colorimetric assay using a model 7600 appara- tus (Hitachi, Tokyo, Japan). The BMD in the lumbar spine (L1- L4) and femur neck, and ward measurements were performed using a QDR 4500 apparatus (Hologic, Waltham, MA, USA) at baseline and 6 months. The serum UcOC was assayed by an en- zyme-linked immunosorbent assay using two monoclonal an- tibodies. Anti-osteocalcin (OC) antibody and a solid-phase anti- Glu 21, 24-OC antibody with recombinant human UcOC (Taka- ra Shuzo, Shiga, Japan) were used. The coefficients of variation (CVs) in the intra- and inter-assay were 7.3% and 9.7%, respec- 1094 http://jkms.org tively. CV was measured twice and the average was determined. The study participants reported their medications to the princi- pal investigators at screening, and at months 3 and 6, and were interviewed about side effects at every visit. For assess study com- pliance, the remaining pill count was checked at all visits, and blood samples were collected at baseline and months 3 and 6. Statistical analysis An independent t test was used to compare the baseline demo- graphics and any changes that occurred after 6 months of inter- vention between the vitamin K group and the control group. To compare any changes in each group after 6 months, the paired t test was used. An intention to treat (ITT) analysis was conduct- ed to obtain standardized outcome variables. In addition, per- protocol (PP) analysis of the 45 subjects was also conducted. A P value < 0.05 was statistically significant. These analyses were done using SPSS version 18.0 (SPSS, Chicago, IL, USA). Ethics statements All participants provided written informed consent and this study was reviewed and approved by the institutional review board of Cha Hospital (EKI-GLA-06-32). RESULTS A total of 385 postmenopausal women over sixty were screened and 78 women were enrolled in the study (Fig. 1). The main rea- sons for ineligibility were the used of restricted medications and occurrence of diseases that could affect bone metabolism. In the ITT analysis comparing the characteristics of the vitamin K group with the control group (Table 1), the age at menopause in the vitamin K group (49.6 ± 2.7 yr) was significantly different DOI: 10.3346/jkms.2011.26.8.1093