Fifteen-Year Incidence of Open-Angle Glaucoma: The Blue Mountains Eye Study.

PURPOSE: To assess the 15-year cumulative incidence of open-angle glaucoma (OAG) in an older Australian population.

DESIGN

Population-based cohort study.

PARTICIPANTS

Three thousand six hundred fifty-four Blue Mountains Eye Study participants from Australia 49 to 97 years of age were examined from 1992 through 1994. Of these, 2335 participants (75.8% of survivors) were reexamined after 5 years (1997-1999), 1952 participants (76.7% of survivors) were reexamined after 10 years (2002-2004), and 1149 participants (56.1% of survivors) were reexamined after 15 years (2007-2010).

METHODS

Goldmann applanation tonometry, stereoscopic optic disc photography, and automated perimetry were performed at baseline and follow-up studies. Participants with suspected glaucoma returned for perimetry, gonioscopy and repeat perimetry and tonometry. After excluding those with OAG at baseline, incident definite OAG was diagnosed when glaucomatous optic disc changes were congruous with visual field defects at any follow-up study. The incident probable OAG group included participants with structural glaucomatous optic disc changes with inconsistent visual field loss. Cumulative and age-standardized incidence rates were estimated using Kaplan-Meier estimates.

MAIN OUTCOME MEASURES: Cumulative and age-standardized 15-year incidence of definite and probable OAG and associated risk factors.

RESULTS

Incident definite OAG developed in 116 participants and probable OAG developed in 24 participants, for a total of 140 cases. The age-standardized 15-year incidence was 5.67% (95% confidence interval [CI], 4.65%-6.68%) for definite and probable OAG, and 4.72% (95% CI, 3.79%-5.64%) for definite OAG. After adjusting for competing risks, incidence of definite and probable OAG was 5.57% (95% CI, 4.66%-6.47%) and that of definite OAG was 4.81% (95% CI, 3.96%-5.66%). Age, pseudoexfoliation, myopia (≥ 3 diopters), and intraocular pressure were strong risk factors for 15-year incidence of OAG.

CONCLUSIONS

This study documented the 15-year incidence of OAG and associated risk factors in an older Australian population. These data are useful for long-term planning of glaucoma-related health services delivery.

FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.