title: Macular pigment optical density measured by dual-wavelength autofluorescence imaging in diabetic and nondiabetic patients: a comparative study.
abstract: OBJECTIVE
  To compare macular pigment optical density (MPOD) in type 2 diabetic and nondiabetic patients by using dual-wavelength autofluorescence imaging and to investigate the correlation of MPOD with glycosylated hemoglobin (HbA1C) and serum lipid levels.
  
  
  METHODS
  Forty-three patients were divided into groups 1 (controls, n = 14), 2 (diabetic without retinopathy, n = 17), and 3 (diabetic with mild nonproliferative retinopathy, n = 12). MPOD was measured with a modified confocal scanning laser ophthalmoscope and compared among groups (analysis of variance). The correlation of HbA1C and serum lipid (HDL, LDL, total cholesterol, and triglycerides) levels with MPOD was determined for each group (linear regression analysis).
  
  
  RESULTS
  Mean ± SD ages in groups 1 (56.2 ± 11.7 years), 2 (58.6 ± 11.5 years), and 3 (62.8 ± 9.8 years) were similar (P = 0.324). Mean MPOD averaged in a 2°-diameter circle around the fovea was significantly different between the three groups: 1, (0.29 ± 0.07 density units [DU]), 2 (0.22 ± 0.09 DU), and 3 (0.14 ± 0.05 DU) (P < 0.001). There was a significant difference in mean MPOD levels at 0.5° between groups 1 (0.51 ± 0.12 DU) and 2 (0.24 ± 0.11 DU; P < 0.001), but not between groups 2 and 3 (0.33 ± 0.15 DU; P > 0.05). A significant inverse correlation was observed between HbA1C levels and mean MPOD, averaged at 2° around the fovea in all patients (r = -0.63, P < 0.001). No significant correlations were found between MPOD and serum lipid levels or age.
  
  
  CONCLUSIONS
  Type 2 diabetic patients, with or without retinopathy, had reduced MPOD when compared with that in nondiabetic patients. In addition, a significant inverse correlation between MPOD and HbA1C levels was observed.
authors.affiliation: Retina Service, Department of Ophthalmology, The New York Eye and Ear Infirmary, New York, New York 10003, USA.
authors.forename: Verônica Castro
authors.initials: VC
authors.lastname: Lima
authors.forename: Richard B
authors.initials: RB
authors.lastname: Rosen
authors.forename: Mauricio
authors.initials: M
authors.lastname: Maia
authors.forename: Tiago Santos
authors.initials: TS
authors.lastname: Prata
authors.forename: Syril
authors.initials: S
authors.lastname: Dorairaj
authors.forename: Michel Eid
authors.initials: ME
authors.lastname: Farah
authors.forename: Juliana
authors.initials: J
authors.lastname: Sallum
mesh_terms: D003720:Densitometry; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism*; D003930:Diabetic Retinopathy / Q000378:metabolism*; D005260:Female; D005451:Fluorescein Angiography; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007089:Image Enhancement; D008055:Lipids / Q000097:blood; D014975:Lutein / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009887:Ophthalmoscopy; D011446:Prospective Studies; D012160:Retina / Q000378:metabolism*; D012168:Retinal Pigments / Q000378:metabolism*; D024341:Xanthophylls / Q000378:metabolism*; D065146:Zeaxanthins
chemical_list: D006442:Glycated Hemoglobin; D008055:Lipids; D014975:Lutein; D012168:Retinal Pigments; D024341:Xanthophylls; D065146:Zeaxanthins; C517652:hemoglobin A1c protein, human