Glucosamine, Glaucoma Complication Studied

A new research letter in JAMA explored the possible relationship between glucosamine supplementation and increased intraocular pressure (IOP) in glaucoma patients, but industry experts suggest the data is preliminary.

In the retrospective study, 17 patients were divided into two groups, one with baseline IOP measurements who began glucosamine supplementation, while the others did not have preexisting IOPs before starting glucosamine (JAMA Ophthalmol.  May 2013. doi:10.1001/.jamainternmed.2013.227). IOP increased significantly from before glucosamine supplementation. Patients discontinuing glucosamine experienced large decreases in IOP.

However, "The study really lacks some important controls that would make the weight of this evidence very limited," said Duffy MacKay, N.D., vice president, scientific and regulatory affairs, The Council for Responsible Nutrition (CRN).

MacKay explained the small study didn't take into account many variables, such as dosage, compliance or duration. "When you have such a small number, those factors really impact the validity of the results," he said, noting it's important to realize these finds are very preliminary.

"The only type of individual who may be interested in these results is someone who has glaucoma and is currently taking glucosamine sulfate," he said. "These individuals should talk to their doctors and make sure they're monitoring their IOP."

It's good reason to do a larger trialit