medwireNews: Vitamin K deficiency may play a role in the development of osteoarthritis, suggests research published in TheAmerican Journal of Medicine.
Multicenter Osteoarthritis (MOST) Study participants with subclinical plasma levels (≤0.5 nM) of phylloquinone (vitamin K) were significantly more likely than participants with adequate vitamin K to have incident radiographic knee osteoarthritis (risk ratio [RR]=1.56), after adjusting for confounding factors.
Furthermore, over 30 months of follow-up, vitamin K-deficient participants were significantly more likely to develop osteoarthritis in one (RR=1.33) or both knees (RR=2.12) than in neither knee.
"This study provides insight into a potential novel risk factor for development of knee osteoarthritis that may have cartilage-specific effects," say Devyani Misra (Boston University School of Medicine, Massachusetts, USA) and co-authors.
"These findings have clinical implications given the potential for vitamin K to be a simple and inexpensive therapy for knee osteoarthritis, a condition that is both prevalent and disabling, but lacks effective therapeutic and prophylactic options."
The researchers examined data for 1180 study participants. Vitamin K plasma levels were taken at baseline and 9.2% of participants were vitamin K-deficient. Of the 1340 knees free from radiographic osteoarthritis at baseline, 14.5% had developed osteoarthritis after 30 months and two knees underwent knee replacement surgery.
The prevalence of knee osteoarthritis was 21.2% in vitamin K-deficient participants versus 13.9% of participants with adequate vitamin K levels.
Vitamin K-deficient participants were significantly more likely to have cartilage lesions on magnetic resonance imaging (RR=2.39) than nondeficient patients, and there was a trend towards deficiency and the presence of incident osteophytes grade 2 or higher(RR=2.35), although this did not reach significance.
The researchers note, however, that since few knees were free from osteophytes at baseline, they were unable to address the true impact of vitamin K deficiency on the early stages of this marker.
"Biologically, there is a plausible rationale for the association of vitamin K with osteoarthritis," Misra et al write, explaining that the vitamin is an essential co-factor for the gamma-carboxylation of Gla proteins involved in the regulation of bone and cartilage mineralization.
The team therefore concludes: "Future studies evaluating the efficacy of vitamin K as a therapeutic or preventative agent for incident osteoarthritis appear warranted."
By Lynda Williams, Senior medwireNews Reporter