Factors Associated with Improvement and Worsening of Visual Acuity 2 Years after Focal/Grid Photocoagulation for Diabetic Macular Edema
Received 1 July 2009; received in revised form 30 September 2009; accepted 1 October 2009. published online 01 February 2010. Corrected Proof
Purpose
To identify factors associated with the visual acuity outcome after focal/grid photocoagulation for diabetic macular edema (DME) among eyes randomized to the focal/grid photocoagulation treatment group within the Diabetic Retinopathy Clinical Research Network (DRCR.net) trial comparing triamcinolone with focal/grid laser.
Design
Multicenter, randomized, clinical trial.
Participants
Three hundred thirty eyes with DME assigned to the focal/grid photocoagulation group, visual acuity 20/40 to 20/320, and optical coherence tomography (OCT) central subfield thickness ≥250 microns.
Methods
Eyes were treated with a protocol-defined photocoagulation technique, which was repeated at 4-month intervals for persistent or recurrent edema. Separate logistic regression models were used to evaluate the associations of demographic, clinical, OCT, and fundus photographic variables with visual acuity improvement or worsening of ≥10 letters from baseline to 2 years. The association of the initial visual acuity outcome after treatment with the subsequent visual acuity course also was evaluated.
Main Outcome Measures
Visual acuity measured with the electronic Early Treatment Diabetic Retinopathy Study method.
Results
Worse baseline visual acuity was the only factor found to be associated with more frequent visual acuity improvement (P<0.001), and both greater baseline OCT-measured retinal volume (P = 0.001) and better baseline visual acuity (P = 0.009) were found to be associated with more frequent visual acuity worsening. Visual acuity outcomes were similar in eyes with and without prior macular or panretinal photocoagulation. The initial visual acuity outcome at 4 months was not generally predictive of the subsequent course. Many eyes that worsened ≥10 letters from baseline to 4 months subsequently improved, and many eyes that initially improved, subsequently worsened.
Conclusions
At this time, focal/grid photocoagulation remains the standard management for DME and these results do not alter this paradigm.
Financial Disclosure(s)
Proprietary or commercial disclosure may be found after the references.
1Joslin Diabetes Center and Department of Ophthalmology, Harvard Medical School, Cambridge, Massachusetts
3Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland
4University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
5National Eye Institute/National Institute of Health, Bethesda, Maryland
Correspondence Allison R. Edwards, M.S., c/o Jaeb Center for Health Research, 15310 Amberly Drive, Suite 350, Tampa, FL 33647
Manuscript no. 2009-886.
Available online: •••.
A published list of the Diabetic Retinopathy Clinical Research Network investigators and staff participating in this protocol can be found in Ophthalmology 2008;115:1447–9, 1449 e1-10 with a current list available at www.drcr.net (Accessed August 26, 2009).
The authors have made the following disclosures:
Dr. Neil M. Bressler: Financial relationships: Grants to investigators at The Johns Hopkins University are negotiated and administered by the institution which receives the grants, typically through the office of Research Administration. Individual investigators who participate in the sponsored project(s) are not directly compensated by the sponsor, but may receive salary or other support from the institution to support their effort on the project(s). Dr. Neil Bressler is Principal Investigator for the following: Allergan, Bausch & Lomb, Bristol-Meyers Squibb, Carl Zeiss Meditec, EMMES Corporation, Genentech, Lumenis, Notal Vision, Novartis, Othera, QLT, Regeneron, Steba Biotech. Dr. Susan Bressler (spouse) is Co-Investigator for the following: Genentech, Inc. Dr. Susan Bressler has been or is presently Consultant for the following: AstraZeneca, Genentech, Notal Vision, Pfizer. However, we do not believe that any of these constitutes a financial conflict of interest for this manuscript.
Dr. Michael S. Ip receives consultant fees for QLT, Sirion Therapeutics, Heidelberg Engineering. He also receives financial support from Allergan. However, we do not believe that any of these constitutes a financial conflict of interest for this manuscript.
Supported through a cooperative agreement from the National Eye Institute and the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, U.S. Department of Health and Human Services EY14231, EY14269, EY14229.
The funding organization participated in oversight of the conduct of the study and review of the manuscript but not directly in the design of the study, the conduct of the study, data collection, data management, data analysis, interpretation of the data, or preparation of the manuscript.
Allergan, Inc. provided the triamcinolone and topical antibiotics after successfully competing for a request for proposals issued by DRCR.net for a company to provide a preservative-free triamcinolone for the study. As per the DRCR.net Industry Collaboration Guidelines (available at www.drcr.net), the DRCR.net had complete control over the design of the protocol, ownership of the data, and all editorial content of presentations and publications related to the protocol. Allergan, Inc. has provided unrestricted funds to DRCR.net for its discretionary use.
A complete list of all DRCR.net investigator financial disclosures can be found at www.drcr.net (Accessed August 26, 2009).
ABSTRACT