Ametropia prevalence of primary school students in Chinese multi-ethnic regions

ABSTRACT

Introduction

To explore the prevalence of visual impairment due to uncorrected ametropia from primary students in multi-ethnic regions of Yunnan (Southern China).

Methods

Primary school students of 7 ~ 12 years old from 5 multi-ethnic regions were screened. Cycloplegic refraction and subjective trial lens visual acuity were measured in all children with distance unaided visual acuity < 20/20. Gender, ages, ethnics, and regions were assessed with analysis of difference and Odds Ratio (OR) respectively, by statistics software R.

Results

Of all 24296 children, the incidence rate for visual impairment from ametropia was 19.18% (myopia accounted for 94.31%) for 7 ~ 12 years old in Yunnan primary schools in a multi-ethnic region. Myopia prevalence differed significantly among gender, ages, ethnics, and regions (P = .0003, P < .00001, P < .00001, P < .00001, respectively). Girls were more prone to have myopia (OR = 1.19, 95%, CI = 1.11–1.27) than boys; the risk of myopia increased with age: 9–10 years OR = 2.6 (95% CI = 2.62–3.2), 11–12 years OR = 6.6 (95% CI = 6–7.26). Three ethnic minorities surveyed were less prone to myopia than Han: Dai OR = 0.62 (95% CI = 0.47–0.8) Hani OR = 0.56 (95%CI = 0.41–0.76) Buyi OR = 0.50 (95% CI = 0.4–0.62).

Conclusions

Myopia, not corrected by glasses, was the most frequent cause of visual impairment in Yunnan primary schools, in a muli-ethnic region. Boys, young children and certain ethnic minorities were less prone to myopia.

KEYWORDS:

• Ametropia
• prevalence
• primary school students
• myopia
• multi-ethnic

Acknowledgments

Thanks Dr. Zhang Yang for design this project; Thanks Dr. Zhang Qian worked with optometrists and technicians from Tianming ophthalmology and optometry clinics who joined the screening. Author-Zhang Yang was the sponsor of the project; Author-Qiu Kaikai initiated English manuscript and participating communication and revising details; Author-Zhang Qian drafted Chinese manuscript as part of his thesis; Author-Li Yan was the supervision for final approval of the version to be published.

Thanks Wu You-Wei, a scholar from the department of epidemiology and biostatistics, school of public health of Kunming Medical School, for his contribution of most statistics analysis to this study.

Declarations

This current study was approved by the institutional review boards and ethnic committee at the University of Kunming Medical School. And it obtained consent by the participants with written informed consent. And there are no competing conflicts of interest. All the authors are consent for publication with available data and materials.

Additional information

Funding

This work was supported by China Yunnan health technology schedule [2017 NS063]; China Soong Ching Ling Foundation [SCLF (2015–2017)].