Purchase this article with an account.
L. Xu, J. Li, Y. Zhen, T. Cui, J. Zhu, J.B. Jonas; Intraocular Pressure in Northern China in an Urban and Rural Population. The Beijing Eye Study . Invest. Ophthalmol. Vis. Sci. 2005;46(13):3643.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: To evaluate the intraocular pressure (IOP) and its demographic associations in an urban and rural population in Northern China.Methods: The Beijing Eye Study is a population–based cohort study in Northern China including in total 4439 subjects out of 5324 subjects asked to participate (response rate 83.4%). The study was divided into a rural part (1973 subjects) and an urban part (2466 subjects). IOP measurements were available for 8813 eyes of 4408 subjects or 99.3% of the whole study population. Mean age was 56.20 ± 10.59 years (40 – 101 years). IOP was measured by non–contact pneumotonometry. Results: Mean IOP was 16.11 ± 3.39 mm Hg (median, 16 mm Hg; range, 7 to 60 mm Hg). In the rural group and the urban population group, respectively, IOP was significantly (p=0.016 and p=0.0.29, resp.) lower in the high–age group (75+ years) than in the middle–age group (55–64 years). In the rural group, IOP was additionally significantly lower in the age group of 40–44 years than in the middle–age group. It suggested a reversed U–like course with a slight increase in IOP from the age subgroup of 40–44 years to the age subgroup of 55–64 years, and a re–decrease towards the age subgroup of 75+ years. In the rural group, IOP was independent of refractive error. In the urban group, IOP was significantly (p<0.001) higher in the myopic group than in the emmetropic group or hyperopic group. In both groups, IOP was statistically independent of gender (p>0.25), and right eye or left eye (p>0.35). In univariate analysis, as well as after stratifying into age groups, IOP did not vary significantly (p=0.11) between the rural population (15.98 ± 3.52 mm Hg) and the urban population (16.07 ± 3.33 mm Hg). Stratifying into subgroups according to refractive error showed that in the myopic subgroups, except of the highly myopic subgroup, IOP was significantly higher in the urban group than in the rural group. Conclusions: In the Northern Chinese population, mean and median of IOP as measured by pneumotonometry is 16 mm Hg with a normal range (mean +/– two standard deviations) of 10 to 22 mm Hg. IOP may slightly increase towards an age of 55–64 years, and re–decrease afterwards. In the urban group, IOP may be higher in the myopic subjects than in non–myopic subjects. IOP may not be markedly different between a rural population and an urban population.
This PDF is available to Subscribers Only