Abstract
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.