Nutritional Therapy with Vitamin K1 Is Effective in the Improvement of Vitamin K Status and Bone Turnover Markers in Patients with Severe Motor and Intellectual Disabilities

• Published in: Journal of Nutritional Science and Vitaminology Vol. 66; no. 3; pp. 278 - 284
• Main Authors: TOZAWA, Kunihiko, TANAKA, Kiyoshi, KUWABARA, Akiko, KITAGAWA, Mari, NAGAE, Akiko, KUMODE, Masao
• Format: Journal Article
• Language: English
• Published: Center for Academic Publications Japan 30.06.2020
• Subjects: bone turnover; protein induced by vitamin K absence (PIVKA-II); severe motor and intellectual disabilities; undercarboxylated osteocalcin (ucOC); vitamin K; γ-carboxylation
• ISSN: 0301-4800; 1881-7742
• DOI: 10.3177/jnsv.66.278

We have previously reported that patients with severe motor and intellectual disabilities (SMID) have a high prevalence of vitamin K deficiency both in the liver and bone. Thus, vitamin K therapy for SMID patients should be considered. In the present study, we have studied the efficacy of nutritional therapy with vitamin K1 for improving their vitamin K status and bone metabolism markers in patients with SMID. During the 3-mo period, 19 patients under enteral feeding received vitamin K1 treatment, the dose of which was determined to meet each subject’s energy requirement. Biomarkers of vitamin K insufficiency; protein induced by vitamin K absence or antagonist-II (PIVKA-II), undercarboxylated osteocalcin (ucOC), intact osteocalcin (intact OC) and bone turnover markers (tartrate-resistant acid phosphatase-5b: TRACP-5b and bone alkaline phosphatase: BAP) were measured at baseline and post treatment. The ucOC/OC ratio was calculated as a more sensitive index than ucOC for vitamin K status in the bone. After treatment, the median vitamin K intake increased from 66 to 183 μg/d, and serum levels of PIVKA-II and ucOC/OC ratio were significantly decreased. Decrements of serum ucOC level and ucOC/OC ratio were significantly associated with vitamin K intake, indicating that both markers well reflect the dose-dependent vitamin K effects. Serum levels of BAP and TRACP-5b were significantly increased after vitamin K1 therapy. Nutritional therapy with vitamin K1 effectively improved the markers for vitamin K status and bone turnover, and was considered to be a good candidate for treatment in SMID patients.