Glaucoma and disability: which tasks are affected, and at what stage of disease?

Abstract

Purpose of review: To summarize recent work from clinical and epidemiological studies that describe how, and at what stage, glaucoma affects the performance of important vision-related activities.

Recent findings: Difficulties with the extremes of lighting are the most frequent complaint in glaucoma. Individuals with bilateral glaucoma also self-report difficulty with a broad array of tasks, including reading, walking, and driving. Bilateral glaucoma is associated with driving cessation and limitation, bumping into objects, slower walking, and falls. Some, but not all, studies also demonstrate higher accident rates in glaucoma. Measurable effects on reading speed have only been observed with field damage severe enough to affect binocular central acuity.

Summary: Glaucoma with bilateral visual field loss is associated with increased symptoms and a measurable decline in mobility and driving. Further work is necessary to establish whether unilateral glaucoma has a significant impact on patients, to determine whether reading difficulty is common in patients with bilateral glaucoma, and to establish the effects of lighting conditions on task performance in glaucoma.

Figure 1

Many distinct relationships between disease severity and disability are possible. Grouping of patients over a range of severity can demonstrate increased disability for the group, while ignoring that the extent of disability may vary drastically over the range of disease severity studied.

Figure 2

The strongest evidence linking disability to eye disease occurs when self-reported ability, measured outcomes, and a plausible mechanism for disability in a given functional domain (i.e. reading, driving, or walking) are all observed to occur at the same level of disease severity.