Evaluation of Homocysteine and Plasminogen Activator Inhibitor-1 Changes in Age Related Macular Degeneration

Age-related maculopathy (ARM) and its late stage, age-related macular degeneration
(ARMD), are degenerative disorders of the central part of the macula. They are the
leading cause of visual impairment and legal blindness among older persons. The
cause of ARMD remains unknown, previous studies suggest an association of markers
of angiogenesis, hemostasis, and endothelial dysfunction with ARMD. The role of
homocysteine and PAI-1have been more controversial, so the purpose of this study
was to evaluate the association between levels of plasma homocysteine and PAI-1 and
age-related macular degeneration (ARMD). Forty eight age –related macular
degeneration cases (23 atrophic and 25 exudative neovascular forms) and 30 controls
with matched age and sex distribution were included in this study. Body mass index
(BMI), lipid profile, plasma leptin, homocysteine and plasminogen activator
inhibitor-1(PAI-1) levels were estimated. The present study points to an association of
ARMD and dyslipidemia, and obesity. Also, there were a significant increase in the
levels of plasma homocysteine and PAI-1 in exudative neovascular age-related
macular degeneration (“wet” type). There was a highly positive correlation between
level of leptin and PAI-1 and BMI in exudative neovascular form. In conclusion,the
present study provides solid evidence that impaired fibrinolysis probably related to
obesity, acting in concert with hyperhomocysteinemia may be involved in the
pathogenesis of age-related macular degeneration. The strategies aimed at reducing
the level of homocysteine and controlling the overproduction of plasminogen
activators inhibitor-1 might offer protection against retinal damage in blinding
retinal diseases especially exudative neovascular age-related macular degeneration.