Distribution of intraocular pressure in healthy Iranian individuals: the Tehran Eye Study

Abstract

Aim: 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 >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. Conclusion: 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. I ntraocular pressure (IOP) is known to be a glaucoma risk factor. 1-5Most published studies on the association between glaucoma and IOP with risk factors have focused on European and American populations and a few on south east Asians. The results show a clear association of IOP and glaucoma prevalence with ethnicity.1 5-10 Furthermore, studies on similar ethnic populations have not given consistent results. For example, mean IOP in a Japanese survey was reported to be 13.3 mm Hg for normal people aged over 40 years 11 while in a Korean study despite enrolling younger people (over 20 years) mean IOP was reported to be 15.5 mm Hg. 12With respect to the differences in IOP assessments in different ethnic populations, and considering IOP as a traditional still in-use screening means of glaucoma detection, 13 14 it would be necessary to implement studies on IOP distribution of different populations to determine its normal range and distribution.Determining IOP distribution in different ethnic populations and factors associated with it can also be helpful in understanding the difference in glaucoma prevalence and its associated factors in different areas of the world. 13 Many factors have been reported to influence IOP. Age, sex, iris colour, diabetes, and blood pressure are the most frequent reported factors, 5 8 10 13 15 16 but the results have been inconsistent.To our knowledge, there have been few studies on the assessment of IOP in a central Asian or Middle Eastern population. This study evaluates IOP distribution in an Iranian population. MATERIALS AND METHODS Participants' enrolmentThe Tehran Eye Study (TES) is a populati...

Factors Associated with Intraocular Pressure before and during 9 Years of Treatment in the Collaborative Initial Glaucoma Treatment Study

“…11,12 Schulzer and Drance found that adjustment for systolic blood pressure accounted for any age effect. 13 Consistent associations with increasing IOP have been reported for increasing systolic blood pressure, 5,7,8,10,12,16,17 darker iris color, 9,14,18 and myopia. 6,14,18 Once glaucoma is diagnosed and treatment is initiated, the influence on IOP attributable to demographic, systemic, and ocular factors might be overwhelmed by the impact of glaucoma treatment.…”

“…[1][2][3] Studies of factors that influence IOP have been conducted in large populations consisting mostly of people without glaucoma. Increasing age has been associated with increasing IOP in most studies, [4][5][6][7][8][9][10] although decreasing IOP with increasing age has been reported in two studies of Asian populations. 11,12 Schulzer and Drance found that adjustment for systolic blood pressure accounted for any age effect.…”

Intraocular pressure in an ophthalmologically normal Japanese population

“…A number of studies have attempted to identify risk factors associated with higher IOP (Armaly 1967;Colton & Ederer 1980;Klein & Klein 1981;Shiose 1984Shiose , 1990David et al 1987;Shiose et al 1991;Sommer et al 1991;Klein et al 1992;Leske et al 1997;Bonomi et al 1998;Nomura et al 1999Nomura et al , 2002Nomura et al , 2004Mori et al 2000;Hashemi et al 2005;Lin et al 2005;Mitchell et al 2005;Nakano et al 2005;Xu et al 2005;Suzuki et al 2006). It is well known that IOP increases with age ) the other important risk factor for glaucoma ) among Black, White and Iranian populations (Armaly 1967;Colton & Ederer 1980;Klein & Klein 1981;David et al 1987;Klein et al 1992; Leske et al 1997;Bonomi et al 1998;Hashemi et al 2005).…”

Effects of three months treatment with sertraline on intraocular pressure and cup-to-disc ratio in patients with anxiety disorders/mixed anxiety and depressive disorder/major depressive disorder and without underlying eye disease

“…In the present study, the mean sertraline dose was 95±2.5 mg daily. Previous studies have revealed (2,17,27,29,31)that the occurrence of this effect depends on the drug plasma level and its metabolites,occurring at a mean daily dose of SSRIs exceeding 20 mg(31) or ≥1 defined daily dose (17). In this study, we evaluated the effect of sertraline on the level of IOP and CDR in patients with anxiety disorders, mixed anxiety and depressive disorder, major depressive disorder.…”