END-OF-LIFE VISION

Despite the improvements in surgical and medical therapy that have taken place over recent decades, a considerable proportion of glaucoma patients will end up with significant visual impairment by the end of their lives, said Carroll Webers MD, PhD at a Glaucoma Day session at the XXXI Congress of the ESCRS in Amsterdam.

“We can talk about surgery and diagnostic techniques but this is what it all comes down to, can we improve the end-of-life visual impairment in glaucoma patients? Therefore, it is relevant to know the extent of the problem,” said Dr Webers, University Eye Clinic Maastricht, The Netherlands.

He presented the findings from a systematic review of published studies concerned with determining the rate and the level of end-of-life visual disability among glaucoma patients as well as the factors associated with that visual disability.

They used Medline to do their literature search, employing the “snowball” method, which meant that all the references of each paper were followed up as well. To be eligible, the studies had to be written in English, Dutch, German or French.

Differences between studies

In all, they found five studies which fit their eligibility criteria. All of the studies were retrospective follow-up studies, but they varied in terms of the years patients died and the type of centre or clinic where they were treated. They also varied in terms of the types of glaucoma diagnosed and the criteria for visual disability and blindness. Therefore, a straightforward meta-analysis was not possible. The mean age at diagnosis was fairly high, ranging from 72 years to 74 years in the different studies.

The mean age at death was also high, ranging from 82.2 years to 85 years. The mean IOP at last visit ranged from 15.2 mmHg to 20.4 mmHg. The mean IOP was highest in a study concerning patients who died during the years 1991 to 2002. That may have been because it involved patients diagnosed at a time prior to the introduction of prostaglandin analogues, Dr Webers said.

The proportion of patients who were visually impaired by glaucoma ranged from nine per cent to 15 per cent, the proportion that were unilaterally blind because of glaucoma ranged from 11 per cent to 24 per cent and the proportion that were bilaterally blind because of glaucoma ranged from zero to 10 per cent. In addition, the proportion of patients who were ineligible to drive because of glaucoma ranged from 18 per cent to 28 per cent.

The factors associated with end-of-life visual impairment from glaucoma were more advanced baseline visual field loss, higher IOP, older age and longer duration of disease. Dr Webers noted that the findings of the study regarding prognostic factors of glaucoma progression were in accordance with another study he and his associates published in March 2013 (Ernest et al, Ophthalmology. 2013 Mar;120:512-9).

That study involved a review of 85 articles on the topic and identified older age and optic disc haemorrhage (in normal-tension glaucoma) as definite prognostic factors and more advanced baseline visual field loss and higher baseline IOP as probable prognostic factors.