Prevalence and factors associated with visual impairment in middle-aged and older Chinese population

This study aimed to estimate the prevalence of visual impairment and to identify the factors associated with it in China.Data for this cross-sectional study were retrieved from the China Health and Retirement Longitudinal Study (CHARLS) for a total of 16,480 subjects who completed the questionnaire between June 2011 and March 2012. The prevalence of visual impairment was estimated considering the complex survey design and response rate. Associated factors were identified using the weighted logistic regression analysis.The overall prevalence of visual impairment among middle-aged and older Chinese adults was 6.22%. Regionally, Qinghai and Gansu provinces showed the highest prevalence of visual impairment, whereas Shanghai showed the lowest prevalence of visual impairment in China. Older age (OR = 1.888; 95% CI: 1.537-2.467) was correlated with a higher likelihood of visual impairment, whereas a non-alcohol intake (OR = 0.072; 95% CI: 0.018-0.246) was correlated with a lower likelihood of visual impairment. Hypertension (OR = 1.299; 95% CI: 1.189-1.467), diabetes (OR = 2.000; 95% CI: 1.163-3.765), lung diseases (OR = 1.795; 95% CI: 1.067-3.019), liver diseases (OR = 1.270; 95% CI: 1.221-2.876), stroke (OR = 1.135; 95% CI: 1.107-3.528), and heart disease (OR = 1.350; 95% CI: 1.104-1.708) were significantly associated with visual impairment.Geographical variations in the prevalence of visual impairment in China were defined, indicating that such variations do exist in China. Age, alcohol intake, hypertension, diabetes, lung diseases, liver diseases, stroke, and heart disease were factors associated with visual impairment.