title: Intraocular pressure and associated factors in children: the Shandong children eye study.
abstract: OBJECTIVE
  We examined the distribution of intraocular pressure (IOP) and its associated factors in children.
  
  
  METHODS
  Using a random cluster sampling from kindergartens, primary schools, and junior and senior high schools from rural Guanxian County and the city of Weihai, the school-based cross-sectional Shandong Children Eye Study included children aged 4 to 18 years. All participants underwent an ocular examination, including ocular biometry, cycloplegic refractometry, and noncontact tonometry.
  
  
  RESULTS
  Mean IOP was 17.6 ± 2.7 mm Hg (range, 10-28 mm Hg). The IOP increased up to an age of 10 years and subsequently decreased with older age. In multivariate regression analysis, higher IOP was associated with female sex (P < 0.001; standardized correlation coefficient β, 0.06; regression coefficient β, 0.34; 95% confidence interval [CI], 0.18, 0.50), higher body mass index (P < 0.001; correlation coefficient β, 0.09; regression coefficient β, 0.07; 95% CI, 0.04,0.09), younger age (P < 0.001; correlation coefficient β, -0.15; regression coefficient β, -0.13; 95% CI, -0.17,-0.10), maternal myopia (P < 0.001; correlation coefficient β, 0.05; regression coefficient β, 0.34; 95% CI, 0.15,0.53), and more time spent indoors with reading/writing (P = 0.002; correlation coefficient β, 0.05; regression coefficient β, 0.07; 95% CI, 0.03,0.11), and with the ocular parameters of longer axial length (P < 0.001; correlation coefficient β, 0.14; regression coefficient β, 0.29; 95% CI, 0.21,0.37) and smaller corneal horizontal diameter (P < 0.001; correlation coefficient β, -0.06; regression coefficient β, -0.31; 95% CI, -0.46,-0.15).
  
  
  CONCLUSIONS
  In children aged 4 to 18 years, IOP showed an M-shaped association with age. Higher IOP was associated with the nonocular parameters of female sex (P < 0.001), higher body mass index (P < 0.001), younger age (P < 0.001), maternal myopia (P < 0.001), and more time spent indoors with reading/writing (P = 0.002), and with the ocular parameters of longer axial length (P < 0.001) and smaller corneal horizontal diameter (P < 0.001).
authors.affiliation: Eye Institute of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China.
authors.forename: Wen Jun
authors.initials: WJ
authors.lastname: Jiang
authors.affiliation: Department of Ophthalmology, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China.
authors.forename: Jian Feng
authors.initials: JF
authors.lastname: Wu
authors.affiliation: The Second Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan Shandong, China.
authors.forename: Yuan Yuan
authors.initials: YY
authors.lastname: Hu
authors.affiliation: Eye Institute of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wu
authors.affiliation: The Second Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan Shandong, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Sun
authors.affiliation: The Second Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan Shandong, China.
authors.forename: Tai Liang
authors.initials: TL
authors.lastname: Lu
authors.affiliation: Eye Institute of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China.
authors.forename: Xing Rong
authors.initials: XR
authors.lastname: Wang
authors.affiliation: Eye Institute of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China.
authors.forename: Hong Sheng
authors.initials: HS
authors.lastname: Bi
authors.affiliation: Department of Ophthalmology, Medical Faculty Mannheim of the Ruprecht-Karls-University Heidelberg, Germany.
authors.forename: Jost B
authors.initials: JB
authors.lastname: Jonas
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D003315:Cornea / Q000473:pathology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D015994:Incidence; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D009798:Ocular Hypertension / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D011159:Population Surveillance; D015995:Prevalence; D011379:Prognosis; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D014065:Tonometry, Ocular / Q000379:methods*
keywords: epidemiology; intraocular pressure; ocular hypertension; population-based study; shandong children eye study