advertisement
'Glaucoma is the leading cause of irreversible of blindness worldwide', (World Health Organization) introduces many a scientific glaucoma article. Yet, little is known about the incidence of blindness due to open angle glaucoma (OAG) in a natural setting. The main limitation of prospective population-based studies is that they are primarily designed to evaluate prevalence instead of incidence. Also, they are unable to assess long-term trends in low-prevalence conditions as OAG. It is, therefore, to the merit of Malihi and colleagues from the Mayo Clinic to have tapped into the rich resource of epidemiological data of the Rochester Epidemiology Project. This longitudinal database is unique in that it covers the entire population (very homogenous, 91% White) from Olmsted County, with interconnected medical records, and virtually all medical care being provided by the Mayo Clinic health system.
This paper is a follow-up to a previous one that reported blindness rates from patients diagnosed in 1965 to 1980. Its main finding is that the probability of glaucoma-related blindness in at least one eye at 20 years after diagnosis decreased from 25.8% (1965-1980) to 13.5% (1981-2000), with a follow-up of 11.2 ± 6.7 years. The authors are to be congratulated for having constructed different models to validate their findings of decreased blindness rates and exclude effects of artifacts. Theirs are important findings: 1) Advances in medical and surgical treatment seem to translate into reduced visual impairment; 2) Yet glaucoma was not diagnosed at earlier stages despite improvement in diagnostic techniques, and the time from glaucoma diagnosis to blindness decreased (!) from 8.7 years in 1965-1980 to 5.8 in 1981-2000. This second point requires better understanding.
Concerted efforts from all stakeholders is needed to make sure that the next twenty-year blindness update from Olmsted county comes closer to the zero mark, while simultaneously millions of patients in underserved regions of the globe gain adequate access to glaucoma care
This paper is rich in data that are beyond the scope of this commentary to present. We would enthusiastically encourage its reading by the glaucoma community and in academic journal clubs. The community should look forward to forthcoming papers from this treasure trove. Although there is some comfort for glaucomatologists to gain from the observed reduction in visual impairment, this is no cause for celebration. If even in this well-deserved and well-educated setting, glaucoma still causes havoc to at least 13.5% of its sufferers, little fantasy is required to imagine its nefarious effect elsewhere. Concerted efforts from all stakeholders is needed to make sure that the next twenty-year blindness update from Olmsted county comes closer to the zero mark, while simultaneously millions of patients in underserved regions of the globe gain adequate access to glaucoma care.