Regional disparities in the prevalence and correlated factors of myopia in children and adolescents in Gansu, China

Abstract

Background: Myopia is a significant public health problem across the globe. This study aimed to examine the regional disparity in prevalence and correlated factors of myopia in children and adolescents in two typical regions, Gannan Tibetan Autonomous Prefecture (Gannan Prefecture for short, a Tibetan residential area) and Wuwei City (a Han residential area) in Gansu Province, China, and to provide a reference for the prevention and control of regional myopia.

Methods: The study was a cross-sectional study of children and adolescents in Gansu Province, China. A total of 6,187 (Wuwei City: 3,266, Gannan Tibetan Autonomous Prefecture: 2,921) students were selected by stratified cluster sampling. Eye examinations and questionnaires were administered to the participants. Myopia is defined as a condition in which the spherical equivalent refractive error of an eye is less than or equal to -0.50 D when ocular accommodation is relaxed. The χ² test and multivariate logistic regression analysis were used to analyze the correlated factors of myopia.

Results: The myopia rate of 6,187 students was 71.4%, and students had a higher rate of myopia (77.5%) in Wuwei City compared to Gannan Prefecture (64.6%) (p < 0.001). The results of multivariate analysis in Wuwei City showed that girls (odds ratio (OR) = 1.325), junior students (OR = 2.542), senior students(OR = 4.605), distance between eyes and book less than one foot (OR = 1.291), and parents with myopia (one, OR = 2.437; two, OR = 4.453) had higher risks of myopia (all, p < 0.05). For Gannan Prefecture, girls (OR = 1.477), senior students (OR = 1.537), daily time spent doing homework ≥2 h (OR = 1.420), the distance between eyes and book less than one foot (OR = 1.205), mean time continuous eye use (0.25-<0.5 h, OR = 1.345, 0.5-<1 h, OR = 1.317, ≥1 h, OR = 1.313), average daily sleep duration <8 h (OR = 1.399), and parents with myopia (one, OR = 1.852; two, OR = 2.913) had higher risks of myopia (all, p < 0.05).

Conclusion: The prevalence of myopia is at a relatively high level in Gansu Province. The prevalence and risk factors for myopia vary by region.

Keywords: children and adolescents; influencing factors; myopia; prevention and control; regional disparity.

Figure 1

Prevalence of myopia of different basic characters students in the two regions (%). 1.1, Boys; 1.2, girls; 2.1, ethnic han; 2.2, Tibetan; 2.3, other ethnic; 3.1, elementary; 3.2, junior; 3.3, senior; 4.1, no parental myopia; 4.2, father or mother with myopia; 4.3, parents with myopia; 5.1, average daily sleep duration < 8 h; 5.2, average daily sleep duration ≥ 8 h; 6.1, daytime outdoor activity < 1; 6.2, daytime outdoor activity 1–2 h; 6.3, daytime outdoor activity ≥2 h.

Figure 2

Prevalence of myopia of different ocular behaviors students in the two regions (%). 1.1, doing eye exercises 0 time/d; 1.2, doing eye exercises 1 time/d; 1.3, doing eye exercises ≥2 times/d; 2.1, recess in the teaching building; 2.2, recess outdoor; 3.1, daily time spend doing homework < 2 h; 3.2, daily time spend doing homework ≥2 h; 4.1, distance between eyes book less than one foot; 4.2, distance between eyes book more than one foot; 5.1, reading occasionally while reclined or lying down; 5.2, reading always while reclined or lying down; 6.1, daily time spend using computer < 1 h; 6.2, daily time spend using computer 1–2 h; 6.3, daily time spend using computer ≥2 h; 7.1, mean time continuous eye use < 0.25 h; 7.2, mean time continuous eye use 0.25–0.5 h; 7.3, mean time continuous eye use 0.5–1 h; 7.4, mean time continuous eye use ≥1 h.