Is exfoliation syndrome a solar-related condition?

This case-control study conducted in the United States and Israel shows that a lifetime of outdoor activities may contribute to exfoliation syndrome (XFS).

The authors also found that sunglasses can reduce the odds of developing XFS, but brimmed-hats offered no protection. Coupled with previous reports showing work over water or snow increases XFS odds, this data suggests that ocular exposure to light from reflective surfaces is important for XFS development.

Investigators administered validated questionnaires to white subjects aged 60 and older (118 subjects with XFS and 106 controls) to explore the relationship between the history of where they lived on the globe and solar exposure, from birth to age 60.

As previous studies have shown, they found that living further away from the equator and increased time outside during the summer raised the risk. Each degree of weighted lifetime average residential latitude away from the equator was associated with 11% increased odds of XFS.

Interestingly, data from the U.S. study site showed that working over snow or water was associated with nearly 4-fold increased odds of XFS, even after controlling for important potentially confounding factors including residential latitude.

The authors note that fresh snow reflects as much as 80% of UV-B during midday, while sand is an intermediate reflecting surface (approximately 7% to 18%) and grass is a poor reflector of UVR (approximately 2% to 4%).

While these findings in no way exclude other genetic and environmental mechanisms in XFS pathogenesis, the confirmation of the link between sun exposure and XFS adds weight to the call for widespread use of ultraviolet-blocking eyewear in XFS prevention.