Folate, or vitamin B9, has been shown to reduce homocysteine levels that are important in warding off a condition known as exfoliation glaucoma (EG) that can provoke blindness and severe visual impairment, researchers have found.
The US-based, 20-30 year cohort study involved about 80,000 men and 40,000 women who were assessed by nurses and health professionals between 1980 and 2010 and found higher intakes of vitamin B6, vitamin B12 and folate were linked to lower homocysteine levels.
“We included a subset of 78,980 women and 41,221 men who were 40 years or older, free of glaucoma, had completed dietary questionnaires, and reported an eye examination during follow-up,” said lead author Jae H Kang, ScD, Channing Division of Network Medicine, Department of Medicine, at Massachusetts Eye and Ear, Brigham and Women’s Hospital (BWH) and Harvard Medical School (HMS).
“Incident cases of EG/SEG, totaling 339 were first identified with the questionnaires and were subsequently confirmed with medical records. Multivariable relative risks for EG/SEG were calculated in each cohort and then pooled with meta-analysis.”
Exfoliation glaucoma (EG) is the most common form of secondary glaucoma (SEG).
The study found vitamin B6 and B12 intake was not associated with EG/SEG risk, and risk fell among those with higher folate intake.
Senior author Louis Pasquale, MD, Glaucoma Service Director, at BWH added: “Our conclusions are that higher folate intake is associated with a lower risk for EG/SEG, supporting a possible causal role of homocysteine in EG/SEG.”
“More work needs to be done but these are critical insights that may give us a better understanding of how EG progresses, which helps to bring us closer to developing interventions or treatments that prevent this blinding disease.”
April 2014. doi:10.1001/jamaophthalmol.2014.100.
‘A Prospective Study of Folate, Vitamin B6, and Vitamin B12 Intake in Relation to Exfoliation Glaucoma or Suspected Exfoliation Glaucoma’
Authors: Jae H. Kang; Stephanie J. Loomis; Janey L. Wiggs; Walter C. Willett; Louis R. Pasquale