Open-Angle Glaucoma and Cardiovascular Mortality: The Blue Mountains Eye Study
Received 10 February 2005; accepted 21 February 2006.
Purpose
To evaluate the association between open-angle glaucoma (termed glaucoma) and 9-year mortality in an older population-based cohort.
Design
Population-based cohort.
Participants
Three thousand six hundred fifty-four persons aged 49 to 97 years (82.4% of the eligible population), residents of the Blue Mountains, west of Sydney, Australia.
Methods
At baseline (1992–1994), glaucoma was diagnosed from congruous typical glaucomatous visual field changes (full-threshold fields) and optic disc cupping (stereo-optic disc photography). Demographic information from baseline participants was matched with the Australian National Death Index data (December 2001) to obtain the number and causes of deaths. Cox proportional hazards regression analysis, controlling for age, male gender, diabetes, hypertension, heart disease, stroke, use of oral β-blockers, current smoking history, alcohol use, myopia, and nuclear cataract were performed to assess hazard ratios for cardiovascular mortality. Adjustments for all-cause mortality also included history of cancer.
Main Outcome Measures
Cardiovascular and all-cause mortality.
Results
At baseline, glaucoma was diagnosed in 108 participants (3.0%). Of 873 deaths (23.9%) before January, 2002, 312 people (8.5%) died of cardiovascular events. The age-standardized all-cause mortality was 24.3% in persons with and 23.8% in those without glaucoma, whereas cardiovascular mortality was 14.6% in persons with and 8.4% in those without glaucoma. After multivariate adjustment, those with glaucoma had a nonsignificant increased risk of cardiovascular death (relative risk [RR], 1.46; 95% confidence interval [CI], 0.95–2.23). Increased cardiovascular mortality was observed mainly in glaucoma patients aged <75 years (RR, 2.78; 95% CI, 1.20–6.47). Further stratified analyses showed that cardiovascular mortality was higher among those with previously diagnosed glaucoma (RR, 1.85; 95% CI, 1.12–3.04), particularly in those also treated with topical timolol (RR, 2.14; 95% CI, 1.18–3.89).
Conclusions
Findings from the Blue Mountains Eye Study demonstrate an increased cardiovascular mortality in persons with previously diagnosed glaucoma. There was a suggestion of higher cardiovascular mortality in glaucoma patients using topical timolol that merits further study.
Department of Ophthalmology, Centre for Vision Research, University of Sydney, Westmead Hospital, Westmead, Australia.
Correspondence to Paul Mitchell, MD, PhD, Department of Ophthalmology, Centre for Vision Research, University of Sydney Westmead Hospital C24, Hawkesbury Road, Westmead, 2145 NSW, Australia.
Manuscript no. 2005-127.
Supported by the Australian National Health and Medical Research Council, Canberra, Australia (grant nos.: 974159, 211069), and Westmead Millennium Institute, University of Sydney, Westmead, Australia.
ABSTRACT