Homocysteine and diabetic retinopathy.
OBJECTIVE
Homocysteine is an emerging risk factor for cardiovascular and nondiabetic ocular vaso-occlusive diseases. However, studies of the relationship between homocysteine and diabetic retinopathy have reported inconsistent results. The purpose of this study was to evaluate the relationship between plasma total homocysteine concentration and diabetic retinopathy.


METHODS
We assessed the homocysteine-retinopathy relationship in 168 men and women with type 2 diabetes in a community-based, cross-sectional study. We photodocumented diabetic retinopathy status and measured plasma total homocysteine concentration using a commercial fluorescence polarization immunoassay enzymatic kit. Data for selected clinical/demographic variables and established risk factors for diabetic retinopathy were obtained from fasting blood samples and an interviewer-assisted lifestyle questionnaire.


RESULTS
A higher mean plasma total homocysteine concentration was observed in diabetic individuals with retinopathy than in those without retinopathy (11.5 mumol/l [95% CI 10.4-12.5] vs. 9.6 mumol/l [9.1-10.2], P = 0.001). Furthermore, the relationship between homocysteine and diabetic retinopathy was not explained by renal dysfunction and was independent of the other major risk factors for diabetic retinopathy (duration of diabetes, A1C, and systolic blood pressure) and determinants of higher homocysteine concentrations (age, sex, and red cell folate) (odds ratio 1.20 [95% CI 1.023-1.41], P = 0.024).


CONCLUSIONS
Plasma total homocysteine concentration may be a useful biomarker and/or a novel risk factor for increased risk of diabetic retinopathy in people with type 2 diabetes.
Brazionis
Laima
L
Department of Medicine, University of Melbourne, St. Vincent's Hospital, P.O. Box 2900, Fitzroy, Victoria 3065, Australia. laimab@medstv.unimelb.edu.au
Rowley
Kevin
K
Itsiopoulos
Catherine
C
Harper
Colin Alexander
CA
O'Dea
Kerin
K
D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure; D003430:Cross-Sectional Studies; D003930:Diabetic Retinopathy / Q000097:blood* / Q000453:epidemiology; D005260:Female; D005451:Fluorescein Angiography; D005492:Folic Acid / Q000097:blood; D006442:Glycated Hemoglobin / Q000032:analysis; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012307:Risk Factors
D015415:Biomarkers; D005492:Folic Acid; D006442:Glycated Hemoglobin; D006710:Homocysteine