title: Associations with Intraocular Pressure in a Large Cohort: Results from the UK Biobank.
abstract: OBJECTIVE
  To describe the associations of physical and demographic factors with Goldmann-correlated intraocular pressure (IOPg) and corneal-compensated intraocular pressure (IOPcc) in a British cohort.
  
  
  METHODS
  Cross-sectional study within the UK Biobank, a large-scale multisite cohort study in the United Kingdom.
  
  
  METHODS
  We included 110 573 participants from the UK Biobank with intraocular pressure (IOP) measurements available. Their mean age was 57 years (range, 40-69 years); 54% were women, and 90% were white.
  
  
  METHODS
  Participants had 1 IOP measurement made on each eye using the Ocular Response Analyzer noncontact tonometer. Linear regression models were used to assess the associations of IOP with physical and demographic factors.
  
  
  METHODS
  The IOPg and IOPcc.
  
  
  RESULTS
  The mean IOPg was 15.72 mmHg (95% confidence interval [CI], 15.70-15.74 mmHg), and the mean IOPcc was 15.95 mmHg (15.92-15.97 mmHg). After adjusting for covariates, IOPg and IOPcc were both significantly associated with older age, male sex, higher systolic blood pressure (SBP), faster heart rate, greater myopia, self-reported glaucoma, and colder season (all P < 0.001). The strongest determinants of both IOPg and IOPcc were SBP (partial R(2): IOPg 2.30%, IOPcc 2.26%), followed by refractive error (IOPg 0.60%, IOPcc 1.04%). The following variables had different directions of association with IOPg and IOPcc: height (-0.77 mmHg/m IOPg; 1.03 mmHg/m IOPcc), smoking (0.19 mmHg IOPg, -0.35 mmHg IOPcc), self-reported diabetes (0.41 mmHg IOPg, -0.05 mmHg IOPcc), and black ethnicity (-0.80 mmHg IOPg, 0.77 mmHg IOPcc). This suggests that height, smoking, diabetes, and ethnicity are related to corneal biomechanical properties. The increase in both IOPg and IOPcc with age was greatest among those of mixed ethnicities, followed by blacks and whites. The same set of covariates explained 7.4% of the variability of IOPcc but only 5.3% of the variability of IOPg.
  
  
  CONCLUSIONS
  This analysis of associations with IOP in a large cohort demonstrated that some variables clearly have different associations with IOPg and IOPcc, and that these 2 measurements may reflect different biological characteristics.
authors.affiliation: NIHR Biomedical Research Centre, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom.
authors.forename: Michelle P Y
authors.initials: MP
authors.lastname: Chan
authors.affiliation: NIHR Biomedical Research Centre, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom.
authors.forename: Carlota M
authors.initials: CM
authors.lastname: Grossi
authors.affiliation: Department of Public Health & Primary Care, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Khawaja
authors.affiliation: Department of Public Health & Primary Care, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Jennifer L Y
authors.initials: JL
authors.lastname: Yip
authors.affiliation: Department of Public Health & Primary Care, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Kay-Tee
authors.initials: KT
authors.lastname: Khaw
authors.affiliation: NIHR Biomedical Research Centre, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom.
authors.forename: Praveen J
authors.initials: PJ
authors.lastname: Patel
authors.affiliation: NIHR Biomedical Research Centre, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom.
authors.forename: Peng T
authors.initials: PT
authors.lastname: Khaw
authors.affiliation: School of Optometry & Vision Sciences, Cardiff University, Cardiff, United Kingdom.
authors.forename: James E
authors.initials: JE
authors.lastname: Morgan
authors.affiliation: Department of Ophthalmology, Nottingham University Hospital NHS Trust, Nottingham, United Kingdom.
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Vernon
authors.affiliation: NIHR Biomedical Research Centre, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom. Electronic address: p.foster@ucl.ac.uk.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Foster
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D015992:Body Mass Index; D015331:Cohort Studies; D003315:Cornea / Q000502:physiology*; D003430:Cross-Sectional Studies; D016208:Databases, Factual; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009313:National Health Programs; D011446:Prospective Studies; D012029:Refraction, Ocular / Q000502:physiology; D011795:Surveys and Questionnaires; D014065:Tonometry, Ocular; D006113:United Kingdom