06.06.06
Indication: Osteoarthritis (OA)
Source: Arthritis Rheum, Mar 29, 2006;54(4):1255-1261.
Research: Investigators conducted an analysis of 672 participants in the Framingham Offspring Study, a population-based prospective observational cohort. Levels of plasma phylloquinone (the primary form of vitamin K) had previously been measured in these participants, for whom researchers also had bilateral hand and knee radiographs. The main outcomes were 1) prevalence ratios (PRs) of OA, osteophytes, and joint space narrowing (JSN) per quartile of plasma phylloquinone level for each joint, adjusting for correlated joints using generalized estimating equations, and 2) adjusted mean number of joints with each feature per quartile of plasma phylloquinone level. Analyses were conducted in hands and knees separately and adjusted for age, sex, body mass index, total energy intake, plasma vitamin D, and femoral neck bone mineral density.
Results: The PRs for OA, osteophytes, and JSN and adjusted mean number of joints with all three features in the hand decreased significantly with increasing plasma phylloquinone levels. For example, as plasma phylloquinone levels rose, the PR for hand OA decreased from 1.0 to 0.7. For the knee, only the PR for osteophytes and the adjusted mean number of knee joints with osteophytes decreased significantly with increasing plasma phylloquinone levels (PR decreased from 1.0 to 0.6). Researchers concluded that observational data support the hypothesis of an association between low plasma levels of vitamin K and increased prevalence of OA manifestations in the hand and knee.
Source: Arthritis Rheum, Mar 29, 2006;54(4):1255-1261.
Research: Investigators conducted an analysis of 672 participants in the Framingham Offspring Study, a population-based prospective observational cohort. Levels of plasma phylloquinone (the primary form of vitamin K) had previously been measured in these participants, for whom researchers also had bilateral hand and knee radiographs. The main outcomes were 1) prevalence ratios (PRs) of OA, osteophytes, and joint space narrowing (JSN) per quartile of plasma phylloquinone level for each joint, adjusting for correlated joints using generalized estimating equations, and 2) adjusted mean number of joints with each feature per quartile of plasma phylloquinone level. Analyses were conducted in hands and knees separately and adjusted for age, sex, body mass index, total energy intake, plasma vitamin D, and femoral neck bone mineral density.
Results: The PRs for OA, osteophytes, and JSN and adjusted mean number of joints with all three features in the hand decreased significantly with increasing plasma phylloquinone levels. For example, as plasma phylloquinone levels rose, the PR for hand OA decreased from 1.0 to 0.7. For the knee, only the PR for osteophytes and the adjusted mean number of knee joints with osteophytes decreased significantly with increasing plasma phylloquinone levels (PR decreased from 1.0 to 0.6). Researchers concluded that observational data support the hypothesis of an association between low plasma levels of vitamin K and increased prevalence of OA manifestations in the hand and knee.