title: Diabetes, hyperglycemia, and central corneal thickness: the Singapore Malay Eye Study.
abstract: OBJECTIVE
  To examine the relationship of diabetes and hyperglycemia with central corneal thickness (CCT) in Malay adults in Singapore.
  
  
  METHODS
  Population-based cross-sectional study.
  
  
  METHODS
  Three thousand two hundred eighty Malay adults ages 40-80 years living in Singapore.
  
  
  METHODS
  The study population was selected using an age-stratified random sampling procedure of Malay 40- to 80-year-olds living in the southwestern part of Singapore. Participants had a standardized interview, examination, and ocular imaging at a centralized study clinic. Central corneal thickness was measured with an ultrasound pachymeter, and nonfasting serum glucose and glycosylated hemoglobin (Hb A(1C)) was obtained from all participants. Diabetes was defined as having nonfasting glucose levels of > or =200 mg/dl (11.1 mmol/l), a self-report of diabetic medication use, or physician diagnosis of diabetes.
  
  
  METHODS
  Central corneal thickness.
  
  
  RESULTS
  Of the 3280 (78.7% response) participants, data on CCT were available on 3239 right eyes. Central corneal thickness was normally distributed, with a mean of 541.2 microm. There were 748 persons with diabetes (23.0%). After controlling for age and gender, central corneas were significantly thicker in persons with diabetes than in those without diabetes (547.2 microm vs. 539.3 microm, P<0.001) and, in the total population, with higher serum glucose (539.6, 540.2, 541.3, and 544.4, comparing increasing glucose quartiles; P = 0.023) and higher Hb A(1C) (537.8, 541.0, 541.4, and 545.5, comparing increasing Hb A(1C) quartiles; P<0.001) levels. In multiple linear regression models adjusting for age, intraocular pressure (IOP), body mass index, and axial length, persons with diabetes had, on average, central corneas 6.50 microm thicker than those of persons without diabetes.
  
  
  CONCLUSIONS
  This population-based study among Malays showed that diabetes and hyperglycemia are associated with thicker central corneas, independent of age and IOP levels. These findings may have implications for understanding the relationship between diabetes and glaucoma.
authors.affiliation: Singapore National Eye Centre & Singapore Eye Research Institute, Singapore.
authors.forename: Daniel H W
authors.initials: DH
authors.lastname: Su
authors.forename: Tien Y
authors.initials: TY
authors.lastname: Wong
authors.forename: Wan-Ling
authors.initials: WL
authors.lastname: Wong
authors.forename: Seang-Mei
authors.initials: SM
authors.lastname: Saw
authors.forename: Donald T H
authors.initials: DT
authors.lastname: Tan
authors.forename: Sunny Y
authors.initials: SY
authors.lastname: Shen
authors.forename: Seng-Chee
authors.initials: SC
authors.lastname: Loon
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Foster
authors.forename: Tin
authors.initials: T
authors.lastname: Aung
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose / Q000032:analysis; D003315:Cornea / Q000473:pathology*; D003430:Cross-Sectional Studies; D003920:Diabetes Mellitus / Q000097:blood / Q000175:diagnosis* / Q000208:ethnology; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D006943:Hyperglycemia / Q000097:blood / Q000175:diagnosis* / Q000208:ethnology; D007429:Intraocular Pressure; D008296:Malaysia / Q000208:ethnology; D008297:Male; D033401:Microscopy, Acoustic; D008875:Middle Aged; D012846:Singapore / Q000453:epidemiology; D014065:Tonometry, Ocular
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin