Gábor Holló and Andreas Katsanos
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proxy for ultraviolet light-induced oxidative stress in the anterior segment of
the eye), high coffee consumption and decreased folate intake may be risk
factors for the development of XFS and XFG in later life [30-32,34,35]. These
hypotheses, however, require confirmation and further research. Figure 2
summarizes the proposed key mechanisms of the development of XFS and
XFG.
Figure 2. Key mechanisms involved in the pathophysiology of XFS and XFG.
GLOBAL HEALTH SIGNIFICANCE
It has been estimated that roughly 60 to 70 million people in the world
have XFS. Approximately 25% of them have high IOP, and one third of them
(i.e., 5-6 million people) have XFG in at least one eye [3,7,8]. The global
impact of XFG becomes even more obvious considering the fact that
approximately half of the patients with glaucoma remain undiagnosed [7,8,36].
This fact can have a profound effect on individual patients and healthcare
resources alike, because XFG is often difficult to control and has a poor long-
term prognosis. Irrespective of the risk for glaucoma, the global impact of
exfoliation should also be seen in the light of increased risk for cataract
formation and increased risk for complications during or after cataract surgery
[14,37].
Numerous reports in the last several years have contributed to the rejection
of the notion that XFS and XFG are entities peculiar to Scandinavia. In fact,
these conditions have been identified in diverse populations worldwide and
XFG may account for 20-25% of open-angle glaucoma cases globally [3,7,8].