Refractive Errors in a Rural Chinese Adult Population: The Handan Eye Study

Presented at: The World Ophthalmology Congress 2008, July 2, 2008, Hong Kong, China.

Received 9 November 2008; received in revised form 22 April 2009; accepted 23 April 2009. published online 10 September 2009.

Purpose

To describe the prevalence of and risk factors for myopia and other refractive errors in a rural, adult, Chinese population.

Design

Population-based, cross-sectional study.

Participants

A clustered, random sampling procedure was used to select 7557 Chinese people aged ≥30 years from Handan, China.

Methods

All eligible subjects were invited to undergo a comprehensive eye examination, including standardized refraction. Myopia, high myopia, and hyperopia were defined as a spherical equivalent (SE) in the right eye of more than −0.5 diopter (D), less than −5.0 D, and 0.5 D or more, respectively. Astigmatism was less than −0.5 D of cylinder. Anisometropia was defined as a difference in SE of >1.0 D between the 2 eyes. Only phakic eyes were analyzed.

Main Outcome Measures

Myopia and other refractive errors.

Results

We included 6491 (85.9% participation rate) eligible subjects in this study. Adjusted to the 2000 China population census, the prevalence rate of myopia was 26.7% (95% confidence interval [CI], 25.6–27.8), hyperopia 15.9 % (95% CI, 15.0–16.8), astigmatism 24.5% (95% CI, 23.5–25.5), and anisometropia 7.7% (95% CI, 7.0–8.4). The prevalence of high myopia was 1.8% (95% CI, 1.5–2.1). Using a multivariate regression model, current smoking (odds ratio [OR], 0.7, 95% CI, 0.5–0.9), hours of reading (OR, 1.2; 95% CI, 1.1–1.4), diabetes (OR, 8.4; 95% CI, 2.2–32.5), and number of family members with myopia (OR, 1.3; 95% CI, 1.1–1.7, for each family member) were associated with myopia in younger persons (30–49 years). High school or higher education (OR, 1.8; 95% CI, 1.1–3.1), diabetes (OR, 1.6; 95% CI, 1.2–2.7), nuclear opacity (OR, 1.7; 95% CI, 1.2–2.3), and number of family members with myopia (OR, 1.5; 95% CI, 1.2–1.9) were risk factors in persons ≥50 years of age.

Conclusions

Myopia affects more than one quarter of rural Chinese persons ≥30 years of age. Myopia is more common in younger people and is associated with different risk factors than in older people.

Financial Disclosure(s)

The authors have no proprietary or commercial interest in any materials discussed in this article.

Available online: September 10, 2009.

1 Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Science Key Laboratory, Beijing, China

2 Handan Eye Hospital, Hebei Province, China

3 Singapore Eye Research Institute, Yong Loo Lin School of Medicine, National University of Singapore

4 Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, Australia

5 Centre for Vision Research, University of Sydney, Australia

6 School of Public Health, Peking University, Beijing, China

7 Wilmer Eye Institute, The Johns Hopkins University, Baltimore, Maryland

8 Department of International Health, The Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland

Correspondence: Ning Li Wang, MD, PhD, Beijing Tongren Eye Center, Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Science Key Laboratory, No.1. Dong Jiao Min Xiang, Dongcheng District, Beijing, 100730, China

Manuscript no. 2008-1327.

Financial Disclosure(s): The authors have no proprietary or commercial interest in any of the materials discussed in this article.

Supported by National Basic Research Program of China (973 Program), Grant 2007CB512201 from the Ministry of Science and Technology of the People's Republic of China, Program of Health Policy for blindness prevention from Ministry of Health the People's Republic of China, Partially funded by the Key Technologies R&D Program. No.2006-10903 from Bureau of Science and Technology of Handan city, Hebei Province, China. With additional support from Beijing Tongren Hospital and the key discipline fund of Bureau of Health, Handan city, Hebei Province, China.

PII: S0161-6420(09)00468-0

doi:10.1016/j.ophtha.2009.04.040

15 of 48