Inverse Relationship between High Blood 25-Hydroxyvitamin D and Late Stage of Age-Related Macular Degeneration in a Representative Korean Population.
Invest Ophthalmol Vis Sci. 2014 Jul 11. pii: IOVS-14-14763. doi: 10.1167/iovs.14-14763. [Epub ahead of print]
Kim EC1, Han K2, Jee D3.
1Ophthalmology, Bucheon St. Mary's Hospital, Bucheon St. Mary's Hospital, 327 Sosa-ro, Wonmi-gu, Bucheon, Gyunggi-do, 420-717, Korea (South), Republic of.
2The Catholic University of Korea, Seoul, 137040, Korea (South), Republic of.
3Department of Ophthalmology and Visual Science, Catholic University of Korea, St. Vincent's Hospital, College of Medicine, #93-6Ji-dong, Paldal-gu, Suwon, 442-723, Korea (South), Republic of donghyunjee at catholic.ac.kr.
Purpose: To investigate the association of 25-hydroxyvitamin D with AMD.
Methods: A population-based, cross-sectional study using a nationwide, systemic stratified, multistage clustered sampling method involved a total of 17,045 subjects aged >40 years who participated in the Korean National Health and Nutrition Examination Survey 2008-2012. All participants underwent standardized interviews, evaluation of blood 25-hydroxyvitamin D levels, and comprehensive ophthalmic examinations. A 45° digital fundus photograph of both eyes was taken under physiologic mydriasis. All fundus photographs were graded using the international classification and grading system.
Results: Blood 25-hydroxyvitamin D levels were 17.5 ng/mL in women and 20.0 ng/mL in men. After adjusting for potential confounders including age, sex, smoking status, hypertension, heart problems, stroke, and sunlight exposure time, the odds ratio (OR) for late AMD significantly decreased in the highest blood 25-hydroxyvitamin D quintile (OR, 0.32; 95% confidence interval CI, 0.12-0.81; P for trend =0.018) compared with the lowest quintile in men, but not in women. Early AMD was not associated with blood 25-hydroxyvitamin D levels in either sex.
Conclusions: High level of blood 25-hydroxyvitamin D was inversely associated with late AMD in men but not women.
Considering anti-angiogenic and anti-fibrotic action of vitamin D, association between two variables warrants further studies.
Copyright © 2014 by Association for Research in Vision and Ophthalmology.
After removing the sex confounder how could they possibly think that there would be any relationship to sex would remain?