Glaucoma is characterised by progressive optic neuropathy and peripheral visual field loss. It affects 1% to 2% of white people aged over 40 years and accounts for 8% of new blind registrations in the UK. The main risk factor for glaucoma is raised intraocular pressure, but 40% of people with glaucoma have normal intraocular pressure and only 10% of people with raised intraocular pressure are at risk of optic-nerve damage. Glaucoma is more prevalent, presents earlier, and is more difficult to control in black people than in white populations.
Methods and outcomes
We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments for established primary open-angle glaucoma, ocular hypertension, or both? What are the effects of lowering intraocular pressure in people with normal-tension glaucoma? What are the effects of treatment for acute angle-closure glaucoma? We searched: Medline, Embase, The Cochrane Library, and other important databases up to May 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
We found 12 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
In this systematic review we present information relating to the effectiveness and safety of the following interventions: laser trabeculoplasty (alone or plus topical medical treatment), topical medical treatments, and surgical trabeculectomy.
Glaucoma is characterised by progressive optic neuropathy and peripheral visual field loss. It affects 1% to 2% of white people aged over 40 years and accounts for 8% of new blind registrations in the UK.
The main risk factor for glaucoma is raised intraocular pressure (IOP), but up to 40% of people with glaucoma have normal IOP and only about 10% of people with raised IOP are at risk of optic-nerve damage.Glaucoma is more prevalent, presents earlier, and is more difficult to control in black people (especially those of West African descent) than in white populations.Blindness from glaucoma results from gross loss of visual field or loss of central vision and, when the optic nerve is vulnerable, can progress quickly without treatment.
Lowering IOP by laser trabeculoplasty plus topical medical treatment may be more effective at reducing progression of glaucoma in people with primary open-angle or pseudoexfoliation glaucoma, compared with no treatment.
Topical medical treatment may reduce the risk of developing glaucoma in people with ocular hypertension, compared with placebo.
We don't know whether topical medical treatment, laser trabeculoplasty, or surgical trabeculectomy is more effective at maintaining visual fields and acuity in primary open-angle glaucoma. Surgery may increase the risk of developing cataracts.
We don't know whether reducing IOP with medical treatment alone or in combination with other treatments including surgery is more effective than no treatment at reducing progression of visual field loss in people with normal-tension glaucoma.
There is a consensus that medical and surgical treatments are beneficial in people with acute angle-closure glaucoma, although we don't know this for sure because it is unethical to withhold pressure-lowering treatment.
The consensus about how laser treatments compare with medical or surgical treatments in people with acute angle-closure glaucoma is currently uncertain, and more high-quality evidence is needed.