The appropriate form and dosing of vitamin K to benefit relevant outcomes in knee osteoarthritis (OA) are not known. In intervention studies for conditions other than knee OA (e.g., prevention of cardiovascular disease), the most commonly used forms and doses include phylloquinone (vitamin K1; 1000µg or 500µg daily) or menaquinone-7 (MK-7 or vitamin K2; 300µg daily). However, whether these doses are adequate to increase vitamin K to levels that ameliorate risk of adverse OA outcomes is not known. Furthermore, although some studies suggest enhanced bioavailability of MK-7 over vitamin K1, as well as extra-hepatic effects, whether this is relevant for an older population with knee OA is not known, The overall goal of this pilot randomized clinical trial (RCT) is to test different subtypes and doses of vitamin K supplementation in older adults with knee OA and to measure changes in relevant biochemical measures.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
TRIPLE
Enrollment
49
One pill daily for 4 weeks.
One pill daily for 4 weeks.
One pill daily for 4 weeks.
Placebo pill daily for 4 weeks.
Boston Medical Center, Rheumatology Clinic
Boston, Massachusetts, United States
Change in uncarboxylated matrix Gla protein (ucMGP) levels
Plasma ucMGP levels will be measured from blood samples using an enzyme-linked immunoassay (ELISA).
Time frame: Baseline, 4 weeks
Change in phylloquinone levels
Plasma phylloquinone will be measured using high-pressure liquid chromatography (HPLC).
Time frame: Baseline, 4 weeks
Sufficient phylloquinone levels
Defined as the the proportion of participants achieving phylloquinone level of \>1.0 nmol/L, which is the level achieved when adequate intakes are met.
Time frame: Baseline, 4 weeks
Change in menaquinone-7 (MK-7) levels
Menaquinone-7 (MK-7) will be measured from blood samples using HPCL.
Time frame: Baseline, 4 weeks
Study adherence
Adherence wil be assessed by analyzing pill counts for each participant.
Time frame: 4 weeks
Participant acceptability of intervention
Participants will use a 5 point LIkert scale to rate acceptability of the overall study, the pill tste, gastrointestinal tolerance, burden, and blood collection.
Time frame: 4 weeks
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.