title: Gestational diabetes mellitus and retinal microvasculature.
abstract: BACKGROUND
  Small-vessel dysfunction may be an important consequence of chronic hyperglycemia. We examined the association between gestational diabetes mellitus (GDM), a state of transient hyperglycemia during pregnancy, and retinal microvascular changes in pregnant women at 26-28 weeks of pregnancy.
  
  
  METHODS
  A total of 1136 pregnant women with singleton pregnancies were recruited during their first trimester at two major Singapore maternity hospitals in an on-going birth cohort study. Participants underwent an oral glucose tolerance test and retinal imaging at 26-28 weeks gestation (n = 542). We used the 1999 World Health Organization (WHO) criteria to define GDM: ≥7.0 mmol/L for fasting glucose and/or ≥7.8 mmol/L for 2-h post-glucose. Retinal microvasculature was measured using computer software (Singapore I Vessel Analyzer, SIVA version 3.0, Singapore Eye Research Institute, Singapore) from the retinal photographs.
  
  
  RESULTS
  In a multiple linear regression model adjusting for age, ethnicity and maternal education, mothers with GDM had narrower arteriolar caliber (-1.6 μm; 95% Confidence Interval [CI]: -3.1 μm, -0.2 μm), reduced arteriolar fractal dimension (-0.01 Df; 95% CI: -0.02 Df, -0.001 Df;), and larger arteriolar branching angle (1.8°; 95% CI: 0.3°, 3.3°) than mothers without GDM. After further adjusting for traditional risks of GDM, arteriolar branching angle remained significantly larger in mothers with GDM than those without GDM (2.0°; 95% CI: 0.5°, 3.6°).
  
  
  CONCLUSIONS
  GDM was associated with a series of retinal arteriolar abnormalities, including narrower caliber, reduced fractal dimension and larger branching angle, suggesting that transient hyperglycemia during pregnancy may cause small-vessel dysfunction.
authors.affiliation: Singapore Eye Research Institute, Singapore National Eye Centre, 11 Third Hospital Ave, Singapore, 168751, Singapore.|Centre for Quantitative Medicine, Duke-NUS Graduate Medical School, 8 College Road, Singapore, 169857, Singapore.
authors.forename: Ling-Jun
authors.initials: LJ
authors.lastname: Li
authors.affiliation: Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.|Departments of Pediatrics and of Epidemiology, Biostatistics and Occupational Health, McGill University Faculty of Medicine, Montreal, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Kramer
authors.affiliation: Singapore Eye Research Institute, Singapore National Eye Centre, 11 Third Hospital Ave, Singapore, 168751, Singapore.
authors.forename: Robyn J
authors.initials: RJ
authors.lastname: Tapp
authors.affiliation: Singapore Eye Research Institute, Singapore National Eye Centre, 11 Third Hospital Ave, Singapore, 168751, Singapore.
authors.forename: Ryan E K
authors.initials: RE
authors.lastname: Man
authors.affiliation: Centre for Quantitative Medicine, Duke-NUS Graduate Medical School, 8 College Road, Singapore, 169857, Singapore.|KK Women's and Children's Hospital, Singapore, Singapore.
authors.forename: Ngee
authors.initials: N
authors.lastname: Lek
authors.affiliation: Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research, Singapore, Singapore.
authors.forename: Shirong
authors.initials: S
authors.lastname: Cai
authors.affiliation: KK Women's and Children's Hospital, Singapore, Singapore.
authors.forename: Fabian
authors.initials: F
authors.lastname: Yap
authors.affiliation: Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research, Singapore, Singapore.
authors.forename: Peter
authors.initials: P
authors.lastname: Gluckman
authors.affiliation: KK Women's and Children's Hospital, Singapore, Singapore.
authors.forename: Kok Hian
authors.initials: KH
authors.lastname: Tan
authors.affiliation: Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research, Singapore, Singapore.|Singapore Institute for Clinical Sciences, Growth, Development & Metabolism, Singapore, Singapore.
authors.forename: Yap Seng
authors.initials: YS
authors.lastname: Chong
authors.affiliation: Singapore Eye Research Institute, Singapore National Eye Centre, 11 Third Hospital Ave, Singapore, 168751, Singapore.
authors.forename: Jia Yu
authors.initials: JY
authors.lastname: Koh
authors.affiliation: Singapore Eye Research Institute, Singapore National Eye Centre, 11 Third Hospital Ave, Singapore, 168751, Singapore.|Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore.
authors.forename: Seang Mei
authors.initials: SM
authors.lastname: Saw
authors.affiliation: Centre for Quantitative Medicine, Duke-NUS Graduate Medical School, 8 College Road, Singapore, 169857, Singapore. yinbun.cheung@duke-nus.edu.sg.|Department for International Health, University of Tampere, Tampere, Finland. yinbun.cheung@duke-nus.edu.sg.
authors.forename: Yin Bun
authors.initials: YB
authors.lastname: Cheung
authors.affiliation: Singapore Eye Research Institute, Singapore National Eye Centre, 11 Third Hospital Ave, Singapore, 168751, Singapore. wong.tien.yin@snec.com.sg.|Centre for Quantitative Medicine, Duke-NUS Graduate Medical School, 8 College Road, Singapore, 169857, Singapore. wong.tien.yin@snec.com.sg.
authors.forename: Tien Yin
authors.initials: TY
authors.lastname: Wong
mesh_terms: D000328:Adult; D016640:Diabetes, Gestational / Q000503:physiopathology*; D005260:Female; D006801:Humans; D006943:Hyperglycemia / Q000503:physiopathology; D008833:Microcirculation / Q000502:physiology; D055806:Microvessels / Q000502:physiology*; D011247:Pregnancy; D011262:Pregnancy Trimester, Second / Q000502:physiology; D012044:Regression Analysis; D012171:Retinal Vessels / Q000503:physiopathology*; D012846:Singapore; D055815:Young Adult
keywords: Gestational diabetes mellitus; Pregnancy outcomes; Retinal imaging; Retinal microvascular measures; Retinal microvasculature