eAppendix. Diabetic Retinopathy Clinical Research Network
. Pilot Study of Individuals With Diabetic Macular Edema Undergoing Cataract Surgery. JAMA Ophthalmol. 2014;132(2):224-226. doi:10.1001/jamaophthalmol.2013.6209
Copyright 2014 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.
Although cataract surgery is performed in individuals with diabetes mellitus, data are limited regarding visual acuity (VA) or macular edema (ME) outcomes after surgery in eyes with diabetic ME (DME) at the time of surgery.1,2 Prior to an interventional study to try to improve long-term outcomes in these eyes, the Diabetic Retinopathy Clinical Research Network (DRCR.net) conducted an observational study (protocol at http://www.drcr.net) to assess factors affecting success of such an interventional trial. The primary goal of this study was to assess feasibility of recruitment and logistics of interaction among DRCR.net sites and cataract surgeons. Secondary goals were to describe the management of these eyes, any changes in ME (due to DME, postsurgical cystoid ME, or both), and short-term vision outcomes.
This was a prospective, noncomparative study conducted at 30 US sites. Adults with at least 1 eye with DME on clinical examination involving the center of the macula, optical coherence tomography (OCT) central subfield thickness of 250 μm or greater using time-domain OCT or 310 µm or greater using spectral-domain OCT, VA of light perception or better, and scheduled for cataract surgery within 14 days of enrollment were eligible. Cataract surgery was conducted per the individual surgeon’s practice. Protocol visits by study investigators (retina specialists) included a preoperative baseline visit and a 16-week postoperative visit. Preoperative, intraoperative, or postoperative treatments for ME followed the investigators’ and cataract surgeon’s standard care. Standardized best-corrected VA and OCT scans were performed by certified personnel.3 The protocol and Health Insurance Portability and Accountability Act–compliant informed consent forms were approved by the institutional review board for each participating site. Each participant gave written informed consent to participate in the study.
Sixty-eight study participants were enrolled between October 9, 2009, and July 8, 2010, when enrollment was discontinued owing to a slow enrollment rate. Among 63 eyes for which eligibility was confirmed, with baseline characteristics in Table 1, 60 (95%) completed the 16-week visit. Twenty-one eyes (35%) received no treatment for ME during the study. Preoperative treatment, defined as focal/grid laser or intravitreal triamcinolone acetonide within 4 months of surgery or intravitreal anti–vascular endothelial growth factor within 2 months of surgery, was reported in 26 eyes (43%). Four eyes (7%) and 25 eyes (42%) received intraoperative and postoperative ME treatments, respectively. Among eyes receiving ME treatment during the study, 27 (69%) received anti–vascular endothelial growth factor drugs. One eye had a ruptured capsule during surgery. At the 16-week visit, mean change in VA letter score was +12 (95% CI, +8 to +16) (Table 2). Improvement of at least 4 lines in VA was reported in 19 eyes (32%; 95% CI, 20% to 45%), while 6 eyes (10%; 95% CI, 4% to 21%) had VA worsening of at least 2 lines. Mean change in OCT central subfield thickness at the 16-week visit (n = 58) was −11 μm (95% CI, −51 to 28) (Table 2). At least 1-step central subfield logOCT improvement and worsening at the 16-week visit were reported in 11 eyes (18%; 95% CI, 10% to 30%) and 9 eyes (15%; 95% CI, 7% to 27%), respectively.4
Low recruitment in this study sheds doubt on the ability of the DRCR.net to recruit an adequate sample within a reasonable time to pursue an interventional trial for ME in the context of cataract surgery among patients with DME at the time of surgery. The functional and anatomical outcomes reflect heterogeneous presurgical and postsurgical ME management in a cohort with DME. Uncomplicated cataract surgery among persons without diabetic retinopathy typically yields vision outcomes that are more uniformly positive than those observed in this cohort.2,5 However, this study estimated that as many as half of the eyes may have had no meaningful improvement or had worsening of VA. Only a small percentage of eyes had substantial VA loss or definitive worsening in central retinal thickening. The observational nature and the lack of standardization in DME management limit definitive conclusions from this study.
Corresponding Author: Talat Almukhtar, MBChB, Jaeb Center for Health Research, 15310 Amberly Dr, Ste 350, Tampa, FL 33647 (firstname.lastname@example.org).
Published Online: December 5, 2013. doi:10.1001/jamaophthalmol.2013.6209.
Authors/Writing Committee: The following investigators of the Diabetic Retinopathy Clinical Research Network take authorship responsibility for the study results: Susan B. Bressler, MD; Carl W. Baker, MD; Talat Almukhtar, MBChB; Neil M. Bressler, MD; Paul A. Edwards, MD; Adam R. Glassman, MS; Michael H. Scott, MD.
Authors/Writing Committee Affiliations: Wilmer Eye Institute, The Johns Hopkins University, Baltimore, Maryland (S. B. Bressler, N. M. Bressler); Paducah Retinal Center, Paducah, Kentucky (Baker); Jaeb Center for Health Research, Tampa, Florida (Almukhtar, Glassman); Henry Ford Health System, Detroit, Michigan (Edwards); Medical Associates Clinic, PC, Dubuque, Iowa (Scott).
Author Contributions: Dr Almukhtar had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: S. B. Bressler, Baker, N. M. Bressler, Edwards, Glassman.
Acquisition of data: S. B. Bressler, Baker, Almukhtar, Edwards, Scott.
Analysis and interpretation of data: S. B. Bressler, Baker, Almukhtar, N. M. Bressler, Edwards, Glassman.
Drafting of the manuscript: S. B. Bressler, Baker, Almukhtar, Edwards.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Almukhtar, Glassman.
Obtained funding: N. M. Bressler, Glassman.
Administrative, technical, or material support: Almukhtar, Scott.
Study supervision: S. B. Bressler, Baker, N. M. Bressler, Glassman.
Conflict of Interest Disclosures: A complete list of all DRCR.net investigator financial disclosures can be found at http://www.drcr.net. Grants to investigators at The Johns Hopkins University are negotiated and administered by the institution (such as the School of Medicine) that 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 S. B. Bressler is coinvestigator of grants at The Johns Hopkins University sponsored by Bausch & Lomb, Novartis, and Regeneron and receives grants from EMMES Corp and Notal Vision. Dr N. M. Bressler is principal investigator of grants at The Johns Hopkins University sponsored by the following entities (not including the National Institutes of Health): Bausch & Lomb, Bristol-Myers Squibb, Carl Zeiss Meditec, EMMES Corp, ForSight Labs, LLC, Genentech, Genzyme Corp, Lumenis, Notal Vision, Novartis, and Regeneron. No other disclosures were reported.
Funding/Support: This work was supported through cooperative agreements EY14231 and EY018817 from the National Eye Institute and the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, US Department of Health and Human Services.
Role of the Sponsor: The National Institutes of Health participated in oversight of the conduct of the study and review of the manuscript but not directly in the design or conduct of the study, collection, management, analysis, and interpretation of the data, or preparation of the manuscript.
Group Information: A complete list of the Diabetic Retinopathy Clinical Research Network appears in the Supplement.
Correction: This article was corrected online December 19, 2013, to add group information.