Study: Three-quarters of blindness in Tibet is preventable or treatable

Tibetans have a higher prevalence of blindness than other Chinese sub-populations, according to a population-based study. Most of the blindness in the region is from treatable or preventable causes, with cataract the leading cause, the study found. As in other areas of the world, women are affected more than men.

An international team of researchers conducted the cross-sectional study in three of the seven prefectures in the Tibet Autonomous Region of China. The objective of the study was to determine the prevalence of blindness and visual impairment, as well as cataract surgical coverage and outcomes in the region. Study data will be used to develop a 10-year blindness prevention and treatment plan for the region, the researchers said.

A total of 12,644 people were examined. The crude prevalence of blindness, defined as visual acuity of less than 6/60, was 2.3%. After adjusting for age and gender, blindness prevalence was 1.4%.

Visual impairment, defined as one eye with VA of 6/24 to 6/60, was found in 10.9% of the participants. Cataract was the primary cause of blindness, affecting 50.7% of those examined. Macular degeneration was the second most common cause of blindness, in 12.7%; corneal opacity was the third leading cause, in 9.7%.

Treatment and prevention efforts in the region should be tailored accordingly, the study authors recommended.

The study is published in the December issue of British Journal of Ophthalmology.