Glucosamine sulphate and osteoarthritis

Jean-Yves Reginster and colleagues’findings in osteoarthritis

have important clinical implications that go far beyond the joint.

Glucosamine sulphate can stimulate proteoglycan production by chondrocytes

which raises the possibility that it may also stimulate proteoglycan production by smooth muscle cells in the arterial wall. An increase in arterial wall proteoglycans could conceivably lead to greater entrapment of atherogenic lipoproteins and increased atherogenesis.

On the other hand, the compound could possibly decrease metalloproteinase production

in atheroma, which would render atherosclerotic plaques more stable and less likely to rupture.

Osteoarthritis is common in elderly people and glucosamine sulphate will be more likely to be used in this group. The elderly also have more atherosclerosis since advancing age is a surrogate for atherosclerotic burden. Therefore, they may be especially susceptible to the effects of this compound on the vascular wall. The same holds true for individuals with known cardiovascular disease.

In the study reported, 8% of patients in the placebo group had a decrease in blood pressure compared with 2% of those in the glucosamine sulphate group. Perhaps this finding shows some degree of increased arterial stiffness in the treated group, which suggests that glucosamine sulphate affects the arterial wall.

We should not encourage the widespread use of glucosamine sulphate for the treatment of osteoarthritis until larger long-term trials have been done to assess safety issues such as the compound’s effect on atherosclerosis and cardiovascular events. To strengthen joints at the risk of weakening arteries would be unfortunate.