Two-year changes in refractive error and related biometric factors in an adult Chinese population.
OBJECTIVE
This article provides, to our knowledge, the first longitudinal population-based data on refractive error (RE) in Chinese persons.


OBJECTIVE
To study cohort effects and changes associated with aging in REs among Chinese adults.


METHODS
A 2-year, longitudinal population-based cohort study was conducted in southern China. Participants, identified using cluster random sampling, included residents of Yuexiu District, Guangzhou, China, aged 35 years or older who had undergone no previous eye surgery.


METHODS
Participants underwent noncycloplegic automated refraction and keratometry in December 2008 and December 2010; in a random 50% sample of the participants, anterior segment ocular coherence tomography measurement of lens thickness, as well as measurement of axial length and anterior chamber depth by partial coherence laser interferometry, were performed.


METHODS
Two-year change in spherical equivalent refraction (RE), lens thickness, axial length, and anterior chamber depth in the right eye.


RESULTS
A total of 745 individuals underwent biometric testing in both 2008 and 2010 (2008 mean [SD] age, 52.2 [11.5] years; 53.7% women). Mean RE showed a 2-year hyperopic shift from -0.44 (2.21) to -0.31 (2.26) diopters (D) (difference, +0.13; 95% CI, 0.11 to 0.16). A consistent 2-year hyperopic shift of 0.09 to 0.22 D was observed among participants aged 35 to 64 years when stratifying by decade, suggesting that a substantial change in RE with aging may occur during this 30-year period. Cross-sectionally, RE increased only in the cohort younger than 50 years (0.11 D/y; 95% CI, 0.06 to 0.16). In the cross-sectional data, axial length decreased at -0.06 mm/y (95% CI, -0.09 to -0.04), although the 2-year change in axial length was positive and thus could not explain the cross-sectional difference. These latter results suggest a cohort effect, with greater myopia developing among younger persons.


CONCLUSIONS
This first Chinese population-based longitudinal study of RE provides evidence for both important longitudinal aging changes and cohort effects, most notably greater myopia prevalence among younger persons.
Division of Preventive Ophthalmology and State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China.
Mingguang
M
He
Division of Preventive Ophthalmology and State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China.
Xiangbin
X
Kong
Division of Preventive Ophthalmology and State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China.
Qianyun
Q
Chen
Division of Preventive Ophthalmology and State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China.
Yangfa
Y
Zeng
Division of Preventive Ophthalmology and State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China.
Yuanzhou
Y
Huang
Division of Preventive Ophthalmology and State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China.
Jian
J
Zhang
Research School of Biology, Australian National University, Canberra, Australia.
Ian G
IG
Morgan
Division of Preventive Ophthalmology and State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China.
Mirjam E
ME
Meltzer
Division of Preventive Ophthalmology and State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China.
Ling
L
Jin
Division of Preventive Ophthalmology and State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China3ORBIS International, New York, New York.
Nathan
N
Congdon
D000328:Adult; D000367:Age Factors; D000368:Aged; D044466:Asian People; D001699:Biometry; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012030:Refractive Errors; D012044:Regression Analysis