Neuroprotection compared with control for glaucoma

Population: adults with open angle glaucoma

Settings: ophthalmology clinics

Intervention: brimonidine 0.2%

Comparison: timolol 0.5%

Visual field: the proportion of participants with progression of visual field loss at 4 years' follow‐up

RR 0.35 (0.14 to 0.86)

101
(1 study)

⊕⊝⊝⊝
very low^1,2

Visual acuity: the proportion of participants with loss of visual acuity at 4 years' follow‐up

‐

‐

‐

Trial investigators reported visual acuity changes within treatment groups; no between‐group data reported.

Intraocular pressure: mean IOP at 4 years' follow‐up

MD 0.20 (‐0.73 to 1.13)

91
(1 study)

⊕⊝⊝⊝
very low^1,2

Among participants with visual field loss at 4 years, the RR for IOP reduction of 20% or greater was 1.15 (95% CI 0.49 to 2.70) when comparing 9 brimonidine participants with 31 timolol participants (very low certainty).

Vertical cup‐disc ratio: the proportion of participants with asymmetrical vertical cup‐disc ratio greater than 0.3 at 4 years' follow‐up

‐

‐

‐

No vertical cup‐disc ratio outcome was reported by the study.

Adverse effects: ocular allergy to the study medication requiring discontinuation up to 4 years' follow‐up

RR 5.32 (1.64 to 17.26)

178
(1 study)

⊕⊝⊝⊝
very low^1,2

6 participants, 5 in the brimonidine group and 1 in the timolol group, died during the study due to causes unrelated to the study treatments.

Quality of life measures

‐

‐

‐

No quality of life outcome was reported by the study.

Economic data

‐

‐

‐

No economic outcome was reported by the study.

*The primary follow‐up time point for this review was 5 years, however data were only available at 4 years.
**The basis for the assumed risk is risk in the control group. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the control group and the relative effect of the intervention (and its 95% CI).
CI: confidence interval; MD: mean difference; IOP: intraocular pressure; RR: risk ratio

GRADE Working Group grades of evidence
High certainty: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate certainty: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low certainty: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low certainty: We are very uncertain about the estimate.