title: Evaluation of the associations between changes in intraocular pressure and metabolic syndrome parameters: a retrospective cohort study in Japan.
abstract: OBJECTIVE
  The contributions of highly correlated cardiovascular risk factors to intraocular pressure (IOP) are not clear due to underlying confounding problems. The present study aimed to determine which metabolic syndrome parameters contribute to elevating IOP and to what extent.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  A private healthcare centre in Japan.
  
  
  METHODS
  Individuals who visited a private healthcare centre and underwent comprehensive medical check-ups between April 1999 and March 2009 were included (20,007 in the cross-sectional study and 15,747 in the longitudinal study).
  
  
  METHODS
  Changes in IOP were evaluated in terms of ageing and changes in metabolic syndrome parameters. Pearson's correlation coefficients and mixed-effects models were used to examine the relationship of changes in IOP with ageing and changes in metabolic syndrome parameters in cross-sectional and longitudinal studies, respectively.
  
  
  RESULTS
  In the cross-sectional study, IOP was negatively correlated with age and positively correlated with waist circumference, high-density lipoprotein cholesterol (HDL-C) levels, triglyceride levels, systolic blood pressure (SBP), diastolic blood pressure (DBP) and fasting plasma glucose (FPG) levels. In the longitudinal multivariate analysis, the associated IOP changes were -0.12 (p<0.0001) mm Hg with male sex; -0.59 (p<0.0001) mm Hg with 10 years of ageing; +0.42 (p<0.0001) mm Hg with 1 mmol/L increase in HDL-C levels; +0.092 (p<0.0001) mm Hg with 1 mmol/L increase in triglyceride levels; +0.090 (p<0.0001) mm Hg with 10 mm Hg increase in SBP; +0.085 (p<0.0001) mm Hg with 10 mm Hg increase in DBP; and+0.091 (p<0.0001) mm Hg with 1 mmol/L increase in FPG levels.
  
  
  CONCLUSIONS
  Elevation of IOP was related to longitudinal worsening of serum triglyceride levels, blood pressure and FPG and improvement in serum HDL-C levels.
authors.affiliation: Department of Health Sciences, University of Yamanashi, Chuo City, Yamanashi, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yokomichi
authors.affiliation: Department of Ophthalmology, University of Yamanashi, Chuo City, Yamanashi, Japan.
authors.forename: Kenji
authors.identifier: http://orcid.org/0000-0001-8506-8503
authors.initials: K
authors.lastname: Kashiwagi
authors.affiliation: Department of Ophthalmology, University of Yamanashi, Chuo City, Yamanashi, Japan.
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Kitamura
authors.affiliation: Yamanashi Koseiren Health Care Center, Kofu City, Yamanashi, Japan.
authors.forename: Yoshioki
authors.initials: Y
authors.lastname: Yoda
authors.affiliation: Yamanashi Koseiren Health Care Center, Kofu City, Yamanashi, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Tsuji
authors.affiliation: Department of Pediatrics, University of Yamanashi, Chuo City, Yamanashi, Japan.
authors.forename: Mie
authors.identifier: http://orcid.org/0000-0002-5748-7388
authors.initials: M
authors.lastname: Mochizuki
authors.affiliation: Center for Birth Cohort Studies, University of Yamanashi, Chuo City, Yamanashi, Japan.
authors.forename: Miri
authors.initials: M
authors.lastname: Sato
authors.affiliation: Center for Birth Cohort Studies, University of Yamanashi, Chuo City, Yamanashi, Japan.
authors.forename: Ryoji
authors.identifier: http://orcid.org/0000-0003-1791-4119
authors.initials: R
authors.lastname: Shinohara
authors.affiliation: Department of Health Sciences, University of Yamanashi, Chuo City, Yamanashi, Japan.
authors.forename: Sonoko
authors.initials: S
authors.lastname: Mizorogi
authors.affiliation: Department of Health Sciences, University of Yamanashi, Chuo City, Yamanashi, Japan.
authors.forename: Kohta
authors.initials: K
authors.lastname: Suzuki
authors.affiliation: Department of Health Sciences, University of Yamanashi, Chuo City, Yamanashi, Japan.
authors.forename: Zentaro
authors.initials: Z
authors.lastname: Yamagata
mesh_terms: D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000032:analysis*; D001794:Blood Pressure; D008076:Cholesterol, HDL / Q000097:blood*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007429:Intraocular Pressure; D007564:Japan; D008137:Longitudinal Studies; D008297:Male; D024821:Metabolic Syndrome / Q000453:epidemiology*; D008875:Middle Aged; D015999:Multivariate Analysis; D012189:Retrospective Studies; D012307:Risk Factors; D014280:Triglycerides / Q000097:blood; D055105:Waist Circumference
chemical_list: D001786:Blood Glucose; D008076:Cholesterol, HDL; D014280:Triglycerides
keywords: Ageing; Diabetes Mellitus; Intraocular Pressure; Metabolic Syndrome X