Rapid assessment of avoidable blindness in Yueqing, an economically developed area in eastern China.

AIM

To evaluate the prevalence and the causes of blindness, severe visual impairment (SVI), and visual impairment (VI) and to investigate the frequency of cataract surgery in people aged ≥50y in Yueqing, Zhejiang Province, China.

METHODS

A population-based, cross-sectional study was performed using the Rapid Assessment of Avoidable Blindness technique. Eight-seven clusters, each consisting of 50 people aged ≥50y, were selected by probability-proportionate-to-size sampling. Three outreach teams conducted door-to-door visits. Visual acuity (VA) was measured using a tumbling E chart. Lens status and causes of VI were assessed by ophthalmologists for individuals with a VA of <6/12 in either eye. A standardized questionnaire was used to collect information about cataract surgeries.

RESULTS

Of 4350 eligible individuals, 4120 were examined with a 94.7% response rate. Age- and gender-adjusted prevalence of blindness, SVI, and VI were 0.5% (95%CI, 0.3%-0.7%), 0.7% (95%CI, 0.4%-1.0%), and 4.8% (95%CI, 4.2%-5.5%), respectively. Age was associated with an increased prevalence of VI, and the most common cause of VI was untreated cataracts, with the main barriers to cataract surgery being a lack of knowledge or awareness about cataracts. Of the 415 eyes operated on for cataracts, 68 (16.4%) eyes had a poor outcomes (VA<6/60) and 303 (73.0%) had a good outcomes (VA>6/18).

CONCLUSION

Prevalence rates of blindness, SVI, and VI in Yueqing are lower than other reported Chinese population-based studies. Cataracts remain the most common cause of blindness and VI.