Residents of most polluted areas at elevated risk of cataract and glaucoma

The connection between pollution and eye disease risk was explored as part of a presentation at the European Society of Cataract and Refractive Surgeons Congress (ESCRS) (11-15 September, Excel London).

Through a systematic review and meta-analysis of 41 observational studies, the research outlined how people living in the most polluted areas had an up to 70% higher risk of developing glaucoma compared to those living in the least polluted areas.

People living in the most polluted areas also faced a consistently higher risk of cataracts than those living in the least polluted areas.

Dr Ahmed Alnabihi, from King Khaled Eye Specialist Hospital and Research Center in Saudia Arabia, highlighted that it has been known for years that pollution has an effect on the heart and lungs.

“Its effects on the eyes have been much less studied and the existing evidence was scattered and inconclusive,” he said.

Researchers examined several types of pollution as part of the review – including particulate matter, nitrogen dioxide, sulphur dioxide, ozone and carbon monoxide.

Alnabihi shared that the clearest finding revealed by the study was for particulate matter.

“For every meaningful step up in pollution exposure, the risk of glaucoma rose by around 8% and cataract by around 4%. The evidence for age-related macular degeneration was less consistent, although some research supported a link. Other pollutants, including nitrogen dioxide and ozone, showed weaker or more mixed associations,” he explained.

The ophthalmology resident added that fine particles are thought to cause inflammation and oxidative stress in the body.

“Over years of exposure, these effects may damage the optic nerve, which is relevant to glaucoma, or the lens, which is relevant to cataract. Unlike most other organs, the eye is directly open to the environment. The ocular surface – the tear film, conjunctiva and cornea – has no barrier between it and outdoor air,” he highlighted.

Alnabihi observed that the study findings add weight to arguments for more stringent air quality standards.

“Every major clean air policy has been justified primarily on the grounds of cardiovascular and lung health. Our paper adds a new organ system to that conversation,” he said.