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Editorial IGR 8-1

Dear Reader,

Glaucoma Worldwide in 2010-2020

Quigley and Broman (abstract no. 3) reviewed the data on prevalence of glaucoma for the coming 4 to 14 years:

• From 2010-2020 the number of patients with glaucoma will rise from 60.5 tot 79.6 million.

• 74% of glaucoma will be OAG; the vast majority of ACG patients will be seen in Asia (87%)

• Bilateral blindness will rise from 8.4 million in 2010 to 11.2 million in 2020.

• A little less than half of blindness cases will be from ACG.

These staggering figures are for a blinding eye disease for which screening tools do not satisfy the criteria for general population screening. However, there is hope: half of the predicted blindness is due to ACG. New tools for imaging of the anterior chamber angle are becoming available. There usefulness in screening for ACG needs to be established. If these anterior chamber evaluation tools will improve our ability to screen for ACG considerably - which I expect - we have made major progress in the prevention of blindness.

OHTS and EGPS

The US-based Ocular Hypertension Treatment Study and the Europe-based Early Glaucoma Prevention Study have many similarities and combined data analysis has been carried out. The OHTS used various medical treatment modalities to decrease IOP whereas EGPS used only laser and Dorzolamide. OHTS did not use placebo, EGPS did. OHTS did show a significant effect of IOP reduction, EGPS did not. Parrish (abstract no. 177) writes that this important difference can be explained by:

1. selection drop-out of treated and untreated patients with higher IOPs in EGPS.

2. failure to achieve sufficient IOP lowering in EGPS.

Although many important data can be derived from EGPS the most important information unfortunately, effect of treatment, does not seem to be available.

Economic burden

The economic burden of visual impairment ranks with cancer, dementia and arthritis. An editorial in the BJO by Frick and Kymes (British Medical Journal 2006; 90: 255-257) is highly recommended. Visual impairment is not a trivial business happening in a small part of the body. If we combine the Quigley and the Taylor data huge sums of money will have to be spend on visual impairment due to glaucoma. The BJO editorial carefully describes what needs to be done to use Taylor's burden data for economic evaluation. A first step has been made, the next steps - at a global level - are of considerable interest.

Registration of clinical trials

The temptation not to report results of studies of which the results are not attractive to the originators is great. This unfortunate practice results in a bias when literature is reviewed. The remedy proposed by the ICMJE (International Committee of Medical Journal Editors) is that all clinical trials have to be registered in a publicly available database. Results of non-registered trials will not be published. Many journal editors including ARVO editors have signed up to support these proposals. This will be in effect beginning July 1, 2006 for ARVO. Publicly available databases that can be used for registration can be found in IOVS vol. 47 p. 1-2, 2006 together with reasons why ARVO is supporting the registration. This is a major step forward in removing bias from the literature.

Consensus

When this issue of IGR will appear the WGA will have held its third consensus meeting, this time on Angle Closure Glaucoma. The preparation of the final printed report ( the Consensus book) goes through seven stages which are unique for the association:

1. Preparation of chapters in e-Room by group-chairs;

2. Extensive discussion of the chapters by up to 100 experts from all over the world;

3. Preliminary report and consensus statements;

4. Distribution of the preliminary report for comment to the 65 Glaucoma Societies assembled in the WGA;

5. Consensus meeting with presentation of chapters including glaucoma society comments; discussion among participants including representatives of glaucoma societies; formulation of final consensus statements;

6. Writing of the final report and statements;

7. Printing of consensus book.

Erik L. Greve