Abstract
Purpose: :
To evaluate whether glaucoma is related to central corneal thickness (CCT).
Methods: :
The Beijing Eye Study 2006 is a population-based study including 3251 (73.3%) subjects (aged 45+ years) out of 4439 subjects who participated in the survey 2001 and who returned for re-examination. Main outcome measures were central corneal thickness and presence and progression of glaucomatous optic neuropathy.
Results: :
Measurements of CCT were available for 3100 (95.4%) subjects. CCT did not vary significantly (P>0.10) between "Optic Disc Glaucoma" (n=77 (2.5%) subjects; 551±32µm), "Perimetric Glaucoma" (n=33 (1.1%) subjects; 548±32µm), and the normal group (556±33µm). CCT was not significantly associated with neuroretinal rim area (P=0.13) or mean visual field defect as measured by frequency doubling perimetry (P=0.71). In multiple regression analysis, CCT was significantly associated with male gender (P<0.001; Odds ratio (OR): 6.78; 95% confidence intervals (CI): 4.54, 9.06), urban region (P<0.001; OR: 3.86; 95%CI:1.52,6.20) and intraocular pressure measurements (P<0.001), while it was not significantly (P=0.42) associated with chronic open-angle glaucoma. In 124 (4.0%) ocular hypertensive subjects without glaucomatous optic disc abnormalities, mean CCT (582±34 µm) was significantly higher than in the normal group (P<0.001) and than in the glaucoma groups (P<0.001). During follow-up from 2001 to 2006, 42 subjects who showed a progression of, or development of glaucomatous abnormalities of the optic nerve head did not differ from the stable group in CCT.
Conclusions: :
CCT may not be markedly different between glaucomatous eyes and normal eyes. Reasons for discrepancies between the present population-based study and previous hospital-based investigations may be due to the study designs and selection of study participants.
Keywords: clinical (human) or epidemiologic studies: health care delivery/economics/manpower • optic nerve • intraocular pressure