Distribution of intraocular pressure in healthy Iranian individuals: the Tehran Eye Study.
OBJECTIVE
To provide data on the distribution of intraocular pressure (IOP) in an Iranian population.


METHODS
Through a population based, cross sectional study, 4565 Tehran citizens were studied in the Tehran Eye Study. The findings from the participants (n = 3834) aged 10 years and older free of glaucoma diagnosis or suspicion who had undergone applanation tonometry examination are presented. All participants received a standardised protocol including applanation tonometry, fundus examination, demographic data, and an interview. IOP measurement was used to evaluate its distribution by age, sex, and some eye parameters.


RESULTS
Mean (SD) IOP was 14.5 (2.6) mm Hg in the total population, 14.4 (2.7) in men, and 14.5 (2.5) in women. Mean (SD) IOP in people > or =40 years was 15.1 (2.9) mm Hg. IOP increased significantly with age and cup:disc ratio except for a fall in old age. This relation was also observed when individuals without diabetes or hypertension history were analysed. IOP increased with darker eye pigmentation except for blue/grey eyes. There was a non-linear increase in IOP from emmetropic to high myopic eyes.


CONCLUSIONS
Age, iris colour, and cup:disc ratio were related to IOP but not to sex. The distribution of IOP in this study was different from various other studies in different geographical regions and it seems advisable to employ a geographical approach to normal IOP interpretation.
Hashemi
H
H
Farabi Eye Hospital and School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
Kashi
A H
AH
Fotouhi
A
A
Mohammad
K
K
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000375:Aging / Q000502:physiology; D002648:Child; D003430:Cross-Sectional Studies; D005127:Eye Color; D005260:Female; D006801:Humans; D007429:Intraocular Pressure; D007492:Iran / Q000453:epidemiology; D008297:Male; D008365:Manometry; D008875:Middle Aged; D009798:Ocular Hypertension / Q000453:epidemiology*; D012016:Reference Values; D012030:Refractive Errors / Q000503:physiopathology; D017678:Sex Distribution