Determinants of the optic cup to disc ratio in an Asian population: the Singapore Malay Eye Study (SiMES).
OBJECTIVE
To describe the distribution and determinants of the optic cup to disc ratio (CDR) in Malay adults in Singapore.


METHODS
This population-based, age-stratified study examined 3280 Malay people aged 40 to 80 years in Singapore. Participants underwent a standardized interview and an ocular examination. A slitlamp examination measured the vertical dimensions of the disc and cup, excluding areas of peripapillary atrophy and the Elschnig scleral ring.


RESULTS
Vertical CDR was recorded for 3228 right eyes and 3237 left eyes. The mean (SD) CDR was 0.40 (0.15) in both eyes. The CDR in the right eye increased with age (P < .001) and was greater in men vs women (age-adjusted CDR, 0.42 vs 0.39; P < .001). In multiple linear regression, significant determinants of greater CDR were increasing age, male sex, higher intraocular pressure (IOP), lower diastolic blood pressure, lower body mass index, and previous cataract surgery. Of these, higher IOP was the most important determinant of the CDR. After excluding 149 persons with glaucoma, male sex, higher IOP, lower diastolic blood pressure, lower body mass index, and diabetes mellitus were significant predictors of greater CDR.


CONCLUSIONS
Greater vertical CDR was related to male sex, higher IOP, lower diastolic blood pressure, and lower body mass index.
Amerasinghe
Nishani
N
Glaucoma Department, Singapore National Eye Centre, 11 Third Hospital Ave, Singapore 168751.
Wong
Tien Y
TY
Wong
Wan-Ling
WL
Mitchell
Paul
P
Shen
Sunny Y
SY
Loon
Seng-Chee
SC
Saw
Seang-Mei
SM
Foster
Paul J
PJ
Aung
Tin
T
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People / Q000235:genetics*; D001794:Blood Pressure; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D005902:Glaucoma, Open-Angle / Q000208:ethnology / Q000235:genetics*; D006801:Humans; D007429:Intraocular Pressure; D008296:Malaysia / Q000208:ethnology; D008297:Male; D008875:Middle Aged; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000208:ethnology / Q000235:genetics*; D012737:Sex Factors; D012846:Singapore / Q000453:epidemiology