Prevalence of blindness and low vision: a study in the rural Heilongjiang Province of China

Abstract
Background: The prevalence of blind individuals in the north of China is unknown. The study aimed to investigate the prevalence and causes of blindness and low vision in rural areas in Heilongjiang province of China in 2008–2009. Design: Cross-sectional study. Participants or Samples: A cluster random sampling method was used to recruit participants of all ages in rural areas of Heilongjiang. Methods: Trained professionals performed interviews and clinical examinations to measure visual acuity. The relationships between blindness or low vision and age, gender and education level were analysed. Main Outcome Measures: The main outcome measure was prevalence rates of bilateral blindness and bilateral low vision. Results: Of the 11 787 subjects, 10 384 (88.1%) were surveyed. The overall age-adjusted prevalence rates were 0.7% (95% confidence interval: 0.5–0.8%) for bilateral blindness and 1.7% (95% confidence interval: 1.4–1.9%) for bilateral low vision. The prevalence rates of blindness and low vision were higher in the elderly and uneducated population (P < 0.05). The main causes for blindness and low vision were cataracts (44.1 and 46.0%, respectively) and refractive errors (17.7 and 42.5%, respectively). Conclusion: Blindness and low vision are highly prevalent among people with cataracts and refractive errors. Eye care planning must focus on treating the avoidable and curable forms of blindness.