You are seeing this message because your Web browser does not support basic Web standards. Find out more about why this message is appearing and what you can do to make your experience on this site better.


ABOUT ARCHIVES
Advanced Search

Welcome   | My Account | E-mail Alerts | RSS | Access Rights | Sign In


  Vol. 126 No. 6, June 2008 TABLE OF CONTENTS
  Online Only
 •  Online First Table of
Contents
  Clinical Sciences
 •Online Features
 This Article
 •Abstract
 •PDF
 • Reply to article
 •Send to a friend
 • Save in My Folder
 •Save to citation manager
 •Permissions
 Citing Articles
 •Citation map
 •Citing articles on HighWire
 •Citing articles on Web of Science (28)
 •Contact me when this article is cited
 Related Content
 •Related letters
 •Similar articles in this journal
 Topic Collections
 •Diabetic Retinopathy
 •Macular Disorders
 •Cardiovascular System
 •Articles for Residents
 •Cardiovascular Disease/ Myocardial Infarction
 •Drug Therapy
 •Drug Therapy, Other
 •Alert me on articles by topic
 Social Bookmarking
  Add to CiteULike Add to Connotea Add to Delicious Add to Digg Add to Facebook Add to Reddit Add to Technorati Add to Twitter What's this?

Rosiglitazone and Delayed Onset of Proliferative Diabetic Retinopathy

Lucy Q. Shen, MD; Angie Child, MD; Griffin M. Weber, MD, PhD; Judah Folkman, MD{dagger}; Lloyd Paul Aiello, MD, PhD

Arch Ophthalmol. 2008;126(6):793-799.

ABSTRACT



Objective  To evaluate whether rosiglitazone maleate, an oral peroxisome-proliferating activated receptor {gamma} agonist and oral insulin sensitizing agent with potential antiangiogenic activity, delays onset of proliferative diabetic retinopathy (PDR).

Methods  Longitudinal medical record review of all patients treated with rosiglitazone receiving both medical and ophthalmic care at the Joslin Diabetes Center from May 1, 2002, to May 31, 2003 (N = 124), and matched control patients not taking a glitazone drug (N = 158). The mean duration of follow-up was 2.8 years (range, 0.3-9.0 years).

Results  Baseline characteristics and final hemoglobin A1c values (7.6% and 7.8%, respectively) were similar in the rosiglitazone and control groups (P = .10). In eyes with severe nonproliferative diabetic retinopathy at baseline (rosiglitazone group, 14 eyes; control group, 24 eyes), progression to PDR over 3 years occurred in 19.2% in the rosiglitazone group and 47.4% in the control group, representing a 59% relative risk reduction (Wilcoxon, P = .045; log-rank, P = .059). Fewer eyes in the rosiglitazone group experienced 3 or more lines of visual acuity loss (P = .03). The incidence of diabetic macular edema was similar in both groups.

Conclusions  Rosiglitazone may delay the onset of PDR, possibly because of its antiangiogenic activity. Future clinical investigations should consider analysis of this potential benefit along with ongoing evaluation of potential cardiac risk in studies where the risk-benefit profiles are deemed appropriate.



INTRODUCTION


 Jump to Section
 •Top
 •Introduction
 •Methods
 •Results
 •Comment
 •Author information
 •References

Proliferative diabetic retinopathy (PDR), the most common cause of severe visual loss among working age Americans,1 is thought to arise as a result of diabetes-induced retinal microvascular dysfunction, leading to decreased retinal perfusion, hypoxia, and subsequent induction of angiogenic factors, such as vascular endothelial growth factor.2-3 These growth factors induce pathologic retinal neovascularization and increased retinal vascular permeability.4 Current definitively proven therapies to delay retinopathy progression and prevent vision loss—such as intensive blood glucose level and blood pressure control as well as laser photocoagulation,5-9—have drawbacks, including frequent inability to achieve optimal targets and symptoms associated with retinal tissue destruction, respectively.9-11 Promising retina-sparing anti–vascular endothelial growth factor agents currently under investigation, such as bevacizumab (Avastin; Genentech, South San Francisco, California), ranibizumab (Lucentis; Genentech), and pegaptanib sodium (Macugen; OSI Eyetech, Melville, New York) require intravitreal administration every 4 to 6 weeks.12-13

Rosiglitazone maleate (Avandia; GlaxoSmithKline, Research Triangle Park, North Carolina) is an orally administered medication used to improve glycemic control in patients with diabetes mellitus.14 This medication activates the peroxisome-proliferating activated receptor {gamma} (PPAR-{gamma}) and leads to insulin sensitization in adipose and other tissues.14-17 Rosiglitazone has recently been demonstrated to have antiangiogenic properties in vitro18 and in animal models.19-20 However, its effect on preventing angiogenesis in humans has not been previously reported. Because the antiangiogenic properties of rosiglitazone are evident in vitro at concentrations as low as 0.1µM,21 and because serum concentrations of rosiglitazone exceed 0.2µM when administered to healthy men at the lowest prescribed dosage of 2 mg twice a day,22 we investigated whether patients receiving rosiglitazone had delayed onset of PDR compared with patients who were not treated with a glitazone drug.


METHODS


 Jump to Section
 •Top
 •Introduction
 •Methods
 •Results
 •Comment
 •Author information
 •References

The study was initiated in 2003 and approved by the Joslin Diabetes Center Institutional Review Board. Patients fulfilled the following criteria: prescribed rosiglitazone by May 31, 2003, received care at both the Joslin and its affiliated Beetham Eye Institute (BEI), and at least 1 ophthalmic examination at the BEI between May 1, 2002, and May 31, 2003. A control group matched for baseline characteristics and follow-up duration was identified after systemic data from the treatment group were collected. Other selection criteria were the same as for the treatment group, except that control patients had no history of receiving prescriptions for rosiglitazone, pioglitazone hydrochloride, or troglitazone. Data were collected using standardized forms from the Joslin medical records. Systemic data included demographic information, factors affecting progression of diabetic retinopathy (DR) or angiogenesis, and adverse effects associated with rosiglitazone. For this study, type 1 diabetes mellitus was defined as diagnosis of diabetes before age 30 years, whereas type 2 diabetes mellitus was defined as diagnosis at 30 years or older.

Ophthalmic data included visual acuity, clinical DR severity and diabetic macular edema (DME) severity, and treatment of DR and DME. All visual acuity measurements were best-corrected and conducted on Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity charts. Severity of DR and DME were graded by all ophthalmologists at the BEI according to ETDRS clinical guidelines. Individual ophthalmologists were unaware that a particular patient was included in the study at the time of evaluation. Previous studies had shown that the consistency of BEI ophthalmologist grading of DR was comparable to the interreader results of the ETDRS study and to masked evaluation of ETDRS standardized photographs.23 Clinical photographs, when available, were used to confirm clinical DR grading.

STUDY OUTCOMES

The primary study end point was the development of PDR in patients with nonproliferative diabetic retinopathy (NPDR) at baseline. Secondary end points included 3 or more lines worsening of visual acuity on the ETDRS chart (moderate visual loss), evidence of PDR progression in patients with PDR at baseline, and the development of clinically significant macular edema (CSME) in patients with no history of macular edema at baseline.

STATISTICAL ANALYSIS

Comparisons of means between the rosiglitazone and control groups were performed using a 2-sample t test for populations with normal distribution. Categorical data expressed in percentages were compared using a {chi}2 test. When the expected frequencies were excessively small, Fisher exact tests were performed. Analysis of ophthalmic data excluded information from patients who underwent only 1 ophthalmic evaluation during the study period. Survival analysis using the Kaplan-Meier method was used to compare data on cumulative rates with various follow-up times and eyes as a unit. Differences between survival curves of the 2 groups were assessed with both Wilcoxon and log-rank tests. Cumulative percentages were obtained from survival curves at 6 months and annually for up to 6 years of follow-up. P <.05 was defined as statistically significant. All statistical analyses were performed using SAS statistical software, version 9.1.3 (SAS Institute, Cary, North Carolina).


RESULTS


 Jump to Section
 •Top
 •Introduction
 •Methods
 •Results
 •Comment
 •Author information
 •References

BASELINE CHARACTERISTICS

We evaluated 124 rosiglitazone-treated patients and 158 control patients with a mean follow-up period of 2.7 and 2.9 years, respectively. Baseline characteristics were well matched (Table 1). Overall, patients were predominantly white and had type 2 diabetes mellitus; 42.7% of rosiglitazone-treated patients and 42.4% of control patients were women. The mean age of participants in the rosiglitazone group was 62 years and in the control group was 64 years, with 15.4 and 16.9 years since diagnosis of diabetes, and hemoglobin A1c (HbA1c) values of 8.4% and 8.1%, respectively (P = .14). Patients with type 2 diabetes mellitus aged 30 to 45 years represented 36% of the treatment group and 35% of the control group (P = .64). Mean baseline systolic and diastolic blood pressures and mean visual acuity (20/25 in each group) were also similar. Because of medical record policies in effect during the study period, information about ethnicity was available for only 72 patients (58.1%) in the rosiglitazone group and 107 in the control group (67.7%). The percentages of white patients in the 2 groups (rosiglitazone, 84.7%; and control, 73.8%) were not statistically different (P = .08), and the distribution of nonwhite ethnicities was not assessed.


View this table:
[in this window]
[in a new window]
[as a PowerPoint slide]
 
Table 1. Baseline Characteristics and Systemic Data


SYSTEMIC FACTORS

Glycemic control, as measured by the last available HbA1c value, improved comparably in both groups by the end of the study (rosiglitazone, 7.6%; and control, 7.8%; P = .10) (Table 1). Known adverse effects of rosiglitazone, including pedal edema, anemia, abnormal liver function tests, and congestive heart failure, were more frequent in the rosiglitazone group, but none of these differences were statistically significant.

A variety of factors that might affect DR progression or angiogenesis were also assessed (Table 1). Duration was often unavailable for these factors, and thus the analysis was not adjusted for follow-up time. Body mass index (BMI) data (calculated as weight in kilograms divided by height in meters squared) were available for 89.5% of patients in the rosiglitazone group and 90.5% of control patients. The mean BMI of the rosiglitazone group was 2.9 higher than that of the control group (P = .001). Compared with control patients, patients in the rosiglitazone group had less microalbuminuria (52.4% vs 67.7%; P = .009), proteinuria (25.0% vs 38.0%; P = .02), angiotensin-converting enzyme inhibitor or angiotensin receptor blocker use (82.3% vs 96.2%; P < .001), other antihypertensive drug use (87.9% vs 96.2%; P = .008), and insulin use (37.9% vs 67.7%; P < .001). Blood pressures were equivalent at the end of the study. Other angiogenesis-related factors, such as presence of primary or metastatic malignant neoplasms, and celecoxib use were also equivalent.

PROGRESSION TO PDR

Distribution of baseline NPDR severity is shown in Table 2. Severe NPDR was found in 14 eyes (6.4%) in the rosiglitazone group and in 24 eyes (9.3%) in the control group at baseline. Progression to PDR by severity of NPDR at baseline is shown in Figure 1. Within 1 year, PDR developed in 7.7% and 29.2% of the rosiglitazone and control groups, respectively (Figure 1A). At 3 years' follow-up, PDR was found in 19.2% and 47.4% of patients, respectively, representing a 59.5% relative risk reduction in the rosiglitazone group. When accounting for lost to follow-up and follow-up duration, this difference was statistically significant by the Wilcoxon method (P = .045) and neared significance by log-rank method (P = .059). In patients with moderate or mild NPDR at baseline (Figure 1B and C), no significant differences were observed over 3 years. None of the patients without DR at baseline developed PDR during the study. The number of eyes in each group at each follow-up time is indicated in Figure 1 and Figure 2.


View this table:
[in this window]
[in a new window]
[as a PowerPoint slide]
 
Table 2. Effect of Rosiglitazone on VA at 5 Years' Follow-up



Figure 1
View larger version (32K):
[in this window]
[in a new window]
[as a PowerPoint slide]
 
Figure 1. Effect of rosiglitazone on the onset of proliferative diabetic retinopathy (PDR) by baseline retinopathy severity. Kaplan-Meier survival curves showing cumulative percentage progression to PDR for patients treated with rosiglitazone (RSG) and control patients. The number of eyes in each group with more than 1 follow-up visit (year 0) and at the beginning of each follow-up interval is indicated below the x-axis. A, P = .045 by Wilcoxon method, P = .06 by log-rank method. B, Wilcoxon, P = .66; log-rank, P = .87. C, Wilcoxon, P = .95; log-rank, P = .76. D, Wilcoxon, P = .12; log-rank, P = .17. NPDR indicates nonproliferative diabetic retinopathy.



Figure 2
View larger version (68K):
[in this window]
[in a new window]
[as a PowerPoint slide]
 
Figure 2. Effect of rosiglitazone on the development of clinically significant macular edema (CSME). A and B, Kaplan-Meier survival curves showing cumulative percentage progression to CSME in patients treated with rosiglitazone (RSG), who had no macular edema (ME) at baseline (A) or ME but no CSME before treatment (B). C, Patients in the RSG group with pedal edema (PE) and without PE. Number of eyes in each group with more than 1 follow-up visit (year 0) and at the beginning of each follow-up interval is indicated below the x-axis. A, Wilcoxon, P = .28; log-rank, P = .22. B, Wilcoxon, P = .27; log-rank, P = .58. C, Wilcoxon, P = .54; log-rank, P = .10.


If the antiangiogenic actions of rosiglitazone predominantly accounted for the delayed onset of PDR, then prevention of the severe NPDR to PDR transition would be expected, rather than a reduction of NPDR progression. Thus, we evaluated progression to PDR in patients with moderate NPDR at baseline who subsequently developed severe NPDR during follow-up (Figure 1D). In this subgroup, 3 years after the diagnosis of severe NPDR, 11.1% of patients in the rosiglitazone group and 31.8% in the control group developed PDR, representing a 65.1% relative risk reduction (Wilcoxon, P = .12; log-rank, P = .17). Rosiglitazone dosing regimens (4 mg/d, 4 mg twice a day, and 8 mg/d) were also evaluated for PDR prevention; however, with small patient numbers for individual regimens and changing dosage regimens during the study, no statistically significant differences were noted.

VISUAL ACUITY, OCULAR THERAPEUTIC INTERVENTION, AND MACULAR EDEMA

As shown in Table 2, fewer eyes in the rosiglitazone group experienced visual acuity loss of 3 or more lines compared with the control group, regardless of baseline NPDR severity. This difference reached statistical significance overall (Wilcoxon, P = .03; log-rank, P = .03). In eyes without PDR at baseline, fewer eyes in the rosiglitazone group received scatter (panretinal) photocoagulation compared with the control group, but this difference was not statistically significant (rosiglitazone: 9 of 219 [4.1%]; 20 of 259 [7.7%]; P = .09). At baseline, 8 eyes in the rosiglitazone group and 28 eyes in the control group had PDR, and no statistical difference was observed regarding need for additional PRP (each 100%), need for vitrectomy, or development of traction retinal detachment.

Rosiglitazone had been reported to be possibly associated with development of DME.24-25 In our study, rosiglitazone was not associated with an increased incidence of CSME in patients without macular edema at baseline (Wilcoxon, P = .28; log-rank, P = .22) (Figure 2A), nor in patients with milder DME at baseline (Wilcoxon, P = .29; log-rank, P = .58) (Figure 2B). In the rosiglitazone group, patients with pedal edema were not more likely to develop CSME (10.5% at 3 years' follow-up) (Figure 2C) than patients without pedal edema (17.9% at 3 years' follow-up) (Wilcoxon, P = .54; log-rank, P = .10). Overall, slightly fewer eyes in the rosiglitazone group received focal/grid laser treatment for macular edema compared with the control group, but this difference was not statistically significant (rosiglitazone: 26 of 196 [13.3%]; 39 of 246[15.9%]; P = .45).


COMMENT


 Jump to Section
 •Top
 •Introduction
 •Methods
 •Results
 •Comment
 •Author information
 •References

Rosiglitazone is an orally administered PPAR-{gamma} agonist that acts as an insulin sensitizer and is commonly prescribed to control hyperglycemia in patients with diabetes.14-17 Large randomized trials demonstrated that rosiglitazone lowers HbA1c values by 1.2% in patients with a baseline value of 7.5% or greater.26 Rosiglitazone has also been shown to have antiangiogenic properties in laboratory studies.18, 21 In this study, we present 3-year follow-up data suggesting that patients with type 2 diabetes who are treated with rosiglitazone may have delayed onset of PDR and less loss of visual acuity. To our knowledge, this is the first study to show evidence of rosiglitazone-mediated antiangiogenesis in humans.

A previous study21 demonstrated that rosiglitazone mediates antiangiogenesis through PPAR-{gamma} activation in endothelial cells, resulting in direct inhibition of endothelial cell proliferation. Rosiglitazone also causes endothelial cell apoptosis via PPAR-{gamma} and maxi-K channels,27 lowers vascular endothelial growth factor expression, inhibits vascular endothelial growth factor receptors, and increases matrix metalloproteinase inhibitor activity.21, 28 These various mechanisms are likely of biological importance because the antiangiogenic effect of rosiglitazone has been confirmed in animal models19, 21 and is suggested in this study of humans.

In this study, progression rates to PDR in the control group were consistent with previous reports.29 The delayed onset of PDR observed with rosiglitazone treatment is unlikely to be a result of altered blood glucose concentrations because both groups had similar initial and final HbA1c values. Insulin use was higher in the control group as expected, since rosiglitazone has been shown to reduce insulin requirement in patients with type 2 diabetes mellitus.30

Although well matched for key baseline characteristics relevant to the progression of DR, including diabetes type, diabetes duration, HbA1c value, blood pressure, and visual acuity, the retrospective nature of the study resulted in some pertinent group differences.31 On average, the rosiglitazone group had a higher BMI, better renal function, and less use of antihypertensive medications. Adverse effects of rosiglitazone, including weight gain and pedal edema, may account for the increased BMI in this group.32 However, without pretreatment BMI data, a direct association cannot be ascertained. The higher mean BMI in the rosiglitazone group is unlikely to account for the observed retinopathy benefit because higher BMI is associated with worsening of retinopathy.33-34

Rosiglitazone use is associated with improved renal function35 and antihypertensive effects,35-36 as was observed in our patient groups. Microalbuminuria may be associated with increased risk of PDR in patients with diabetes.34, 37 An increased risk of retinopathy progression is associated with elevated blood pressure but not with antihypertensive therapy.7, 38 In our study, both systolic and diastolic blood pressures were well matched between groups during the follow-up period.

Patients treated with rosiglitazone experienced less loss of visual acuity than control patients after 5 years, an effect present regardless of baseline NPDR severity (Wilcoxon and log-rank tests: P = .03) (Table 2). Thus, not all the visual benefit of rosiglitazone may be attributable to prevention of PDR. Determining the reproducibility, mechanism, and magnitude of this effect will require larger prospective studies.

No significant increase in the development of CSME was observed in the rosiglitazone group despite a few reports suggesting that rosiglitazone may induce or exacerbate macular edema in patients with diabetes.24-25 Protein kinase C-β activation is postulated as an underlying mechanism.39 However, a large ongoing prospective clinical trial (Action to Control Cardiovascular Risk in Diabetes) evaluated 3468 participants with diabetes (6865 eyes) and did not find an increased risk of CSME associated with rosiglitazone (oral communication, Emily Chew, MD, National Eye Institute, May 2006).

Our study has limitations inherent to its retrospective design and limited patient numbers. Patient numbers are limited by the prevalence of rosiglitazone therapy in 2003 and the need for medical and ophthalmologic follow-up at the same institution to maximize accurate medical and ocular characterization. Accurate treatment initiation dates of rosiglitazone were not available in some patients who were already receiving therapy before their first visit at Joslin. The relatively small sample size limited study power, particularly with fewer patients completing more than 3 years of follow-up. The usual caveats pertinent to retrospective studies with regard to variability of clinical data recording and collection may also influence the outcome. However, these effects were minimized because of the unique academic setting at the BEI and Joslin: most clinical findings were recorded in standardized electronic medical record templates; visual acuity examiners, refractionists, and visual examination rooms were certified for clinical trials; and BEI staff recorded the severity of retinopathy according to the ETDRS clinical retinopathy grading protocol. Collection of all data was performed using standardized forms. Despite study design limitations, these data provide initial evidence for a possible antiangiogenic effect of rosiglitazone in patients with diabetes. Larger, prospective clinical trials are needed to confirm the role of rosiglitazone in preventing PDR.

Adverse effects of rosiglitazone include peripheral edema (5%-10% of patients), abnormal liver function tests (<1%), and worsening congestive heart failure (<1%).40-41Mild anemia and dose-dependent weight gain of 0.5 to 3.7 kg have been reported.32, 42 In 1999, rosiglitazone was approved by the US Food and Drug Administration43 and, in 2001, more than 8 million prescriptions were dispensed.44 Recently, the safety of rosiglitazone therapy has been questioned in a meta-analysis of 42 of 116 potentially relevant studies, which found that the odds ratio was 1.43 (P = .03) for myocardial infarction and 1.64 (P = .06) for death from cardiovascular causes in patients treated with rosiglitazone.45 An accompanying editorial identified several study design factors to be considered when assessing these data.46 A more recent report found that rosiglitazone was not associated with an increase in death from either cardiovascular causes or all causes. However, rosiglitazone was associated with an increased risk of heart failure and the data were insufficient to determine whether there was an associated increase in the risk of myocardial infarction.47 Additional studies are under way to address the safety issues of this medication in definitive ways.

In light of the recent safety data, careful risk assessment and patient selection will be important for any future studies. However, the potential benefit of rosiglitazone in reducing retinopathy progression and maintaining visual acuity could significantly reduce personal and societal burdens and should be considered if risks can be appropriately managed. In addition, rosiglitazone-mediated antiangiogenesis may have a role beyond the realm of DR, as glitazone treatment has been well tolerated in patients without diabetes in clinical trials.48-49 Thus, rosiglitazone may benefit other pathologic angiogenic conditions such as age-related macular degeneration and certain types of cancer.

In conclusion, this study of 282 patients with diabetes with a mean follow-up time of 2.8 years suggests that orally administered rosiglitazone may delay the onset of PDR in patients with severe NPDR at baseline. Rosiglitazone treatment may also be associated with less loss of visual acuity. However, because this study does not rigorously prove that rosiglitazone either reduces the incidence of PDR or prevents loss of visual acuity, and because there may be adverse effects from therapy, rosiglitazone treatment of patients with diabetes specifically to reduce these ophthalmic complications is not advocated at this time. Determination of the full efficacy and clinical role of rosiglitazone in the treatment of PDR and other angiogenic conditions awaits confirmation of risks and benefits and possibly large-scale definitive studies.


AUTHOR INFORMATION


 Jump to Section
 •Top
 •Introduction
 •Methods
 •Results
 •Comment
 •Author information
 •References

Correspondence: Lloyd Paul Aiello, MD, PhD, Joslin Diabetes Center, 1 Joslin Pl, Boston, MA 02215 (lpaiello{at}joslin.harvard.edu).

Submitted for Publication: June 26, 2007; final revision received October 31, 2007; accepted November 7, 2007.

Author Contributions: Drs Shen, Folkman, and Aiello had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

Financial Disclosure: None reported

Funding/Support: This study was supported in part by the HST Student Research Fund, Harvard Medical School.

Previous Presentation: The results of this study were presented at the annual meeting of the Association for Research in Vision and Ophthalmology; May 2, 2006; Fort Lauderdale, Florida; and received the Dr Henry and Lilian Nesburn Award for the best paper by a resident in June 2007.

Additional Information: This study is dedicated to the memory of David Magoon, who contributed significantly to data collection.

Additional Contributions: Edwin Chen, PhD, provided statistical analysis; Lisa Finston, Garretson Beebe, and Andrew Principe performed data collection; Anne McKay performed electronic data entry; and Om Ganda, MD, provided supporting data.


Author Affiliations: Harvard Medical School (Drs Shen, Child, Weber, Folkman, and Aiello), Beth Israel Deaconess Medical Center (Dr Weber), Children's Hospital Boston (Dr Folkman), and Beetham Eye Institute and Eye Research Section, Joslin Diabetes Center (Dr Aiello), Boston, Massachusetts; and Jules Stein Eye Institute, University of California–Los Angeles (Dr Shen). {dagger}Died January 14, 2008.


REFERENCES


 Jump to Section
 •Top
 •Introduction
 •Methods
 •Results
 •Comment
 •Author information
 •References

1. Aiello LP, Gardner TW, King GL; et al. Diabetic retinopathy. Diabetes Care. 1998;21(1):143-156. FREE FULL TEXT
2. Adamis AP, Miller JW, Bernal MT; et al. Increased vascular endothelial growth factor levels in the vitreous of eyes with proliferative diabetic retinopathy. Am J Ophthalmol. 1994;118(4):445-450. WEB OF SCIENCE | PUBMED
3. Aiello LP, Avery RL, Arrigg PG; et al. Vascular endothelial growth factor in ocular fluid of patients with diabetic retinopathy and other retinal disorders. N Engl J Med. 1994;331(22):1480-1487. FULL TEXT | WEB OF SCIENCE | PUBMED
4. Antcliff RJ, Marshall J. The pathogenesis of edema in diabetic maculopathy. Semin Ophthalmol. 1999;14(4):223-232. PUBMED
5. Diabetic Retinopathy Study Research Group. Photocoagulation treatment of proliferative diabetic retinopathy: clinical application of Diabetic Retinopathy Study (DRS) findings, DRS Report No. 8. Ophthalmology. 1981;88(7):583-600. WEB OF SCIENCE | PUBMED
6. Early Treatment Diabetic Retinopathy Study Research Group. Photocoagulation for diabetic macular edema: Early Treatment Diabetic Retinopathy Study Report No. 1. Arch Ophthalmol. 1985;103(12):1796-1806. FREE FULL TEXT
7. UK Prospective Diabetes Study Group. Tight blood pressure control and risk of macrovascular and microvascular complications in type 2 diabetes: UKPDS 38. BMJ. 1998;317(7160):703-713. FREE FULL TEXT
8. UK Prospective Diabetes Study Group. Tight intensive blood-glucose control with sulphonylureas or insulin compared with conventional treatment and risk of complications in patients with type 2 diabetes: UKPDS 33. Lancet. 1998;352(9131):837-853. FULL TEXT | WEB OF SCIENCE | PUBMED
9. Aiello LM. Perspectives on diabetic retinopathy. Am J Ophthalmol. 2003;136(1):122-135. FULL TEXT | WEB OF SCIENCE | PUBMED
10. Diabetic Retinopathy Study Research Group. Indications for photocoagulation treatment of diabetic retinopathy: Diabetic Retinopathy Study Report No. 14. Int Ophthalmol Clin. 1987;27(4):239-253. FULL TEXT | WEB OF SCIENCE | PUBMED
11. Pender PM, Benson WE, Compton H, Cox GB. The effects of panretinal photocoagulation on dark adaptation in diabetics with proliferative retinopathy. Ophthalmology. 1981;88(7):635-638. WEB OF SCIENCE | PUBMED
12. Gragoudas ES, Adamis AP, Cunningham ET Jr, Feinsod M, Guyer DR. Pegaptanib for neovascular age-related macular degeneration. N Engl J Med. 2004;351(27):2805-2816. FULL TEXT | WEB OF SCIENCE | PUBMED
13. Rosenfeld PJ, Brown DM, Heier JS; et al. Ranibizumab for neovascular age-related macular degeneration. N Engl J Med. 2006;355(14):1419-1431. FULL TEXT | PUBMED
14. Nolan JJ, Jones NP, Patwardhan R, Deacon LF. Rosiglitazone taken once daily provides effective glycaemic control in patients with type 2 diabetes mellitus. Diabet Med. 2000;17(4):287-294. FULL TEXT | WEB OF SCIENCE | PUBMED
15. Lehmann JM, Moore LB, Smith-Oliver TA, Wilkison WO, Willson TM, Kliewer SA. An antidiabetic thiazolidinedione is a high affinity ligand for peroxisome proliferator-activated receptor {gamma} (PPAR {gamma}). J Biol Chem. 1995;270(22):12953-12956. FREE FULL TEXT
16. Raskin P, Rappaport EB, Cole ST, Yan Y, Patwardhan R, Freed MI. Rosiglitazone short-term monotherapy lowers fasting and post-prandial glucose in patients with type II diabetes. Diabetologia. 2000;43(3):278-284. FULL TEXT | WEB OF SCIENCE | PUBMED
17. Vasudevan AR, Balasubramanyam A. Thiazolidinediones: a review of their mechanisms of insulin sensitization, therapeutic potential, clinical efficacy, and tolerability. Diabetes Technol Ther. 2004;6(6):850-863. FULL TEXT | PUBMED
18. Xin X, Yang S, Kowalski J, Gerritsen ME. Peroxisome proliferator-activated receptor {gamma} ligands are potent inhibitors of angiogenesis in vitro and in vivo. J Biol Chem. 1999;274(13):9116-9121. FREE FULL TEXT
19. Murata T, Hata Y, Ishibashi T; et al. Response of experimental retinal neovascularization to thiazolidinediones. Arch Ophthalmol. 2001;119(5):709-717. FREE FULL TEXT
20. Murata T, He S, Hangai M; et al. Peroxisome proliferator-activated receptor {gamma} ligands inhibit choroidal neovascularization. Invest Ophthalmol Vis Sci. 2000;41(8):2309-2317. FREE FULL TEXT
21. Panigrahy D, Singer S, Shen LQ; et al. PPAR-{gamma} ligands inhibit primary tumor growth and metastasis by inhibiting angiogenesis. J Clin Invest. 2002;110(7):923-932. FULL TEXT | WEB OF SCIENCE | PUBMED
22. Freed MI, Allen A, Jorkasky DK, DiCicco RA. Systemic exposure to rosiglitazone is unaltered by food. Eur J Clin Pharmacol. 1999;55(1):53-56. FULL TEXT | WEB OF SCIENCE | PUBMED
23. Bursell SE, Cavallerano JD, Cavallerano AA; et al. Stereo nonmydriatic digital-video color retinal imaging compared with Early Treatment Diabetic Retinopathy Study seven standard field 35-mm stereo color photos for determining level of diabetic retinopathy. Ophthalmology. 2001;108(3):572-585. FULL TEXT | WEB OF SCIENCE | PUBMED
24. Colucciello M. Vision loss due to macular edema induced by rosiglitazone treatment of diabetes mellitus. Arch Ophthalmol. 2005;123(9):1273-1275. FREE FULL TEXT
25. Ryan EH Jr, Han DP, Ramsay RC; et al. Diabetic macular edema associated with glitazone use. Retina. 2006;26(5):562-570. FULL TEXT | WEB OF SCIENCE | PUBMED
26. Raskin P, Rendell M, Riddle MC, Dole JF, Freed MI, Rosenstock J. A randomized trial of rosiglitazone therapy in patients with inadequately controlled insulin-treated type 2 diabetes. Diabetes Care. 2001;24(7):1226-1232. FREE FULL TEXT
27. Kim KY, Cheon HG. Antiangiogenic effect of rosiglitazone is mediated via peroxisome proliferator-activated receptor {gamma}-activated maxi-K channel opening in human umbilical vein endothelial cells. J Biol Chem. 2006;281(19):13503-13512. FREE FULL TEXT
28. Peeters LL, Vigne JL, Tee MK, Zhao D, Waite LL, Taylor RN. PPAR-{gamma} represses VEGF expression in human endometrial cells: implications for uterine angiogenesis. Angiogenesis. 2005;8(4):373-379. FULL TEXT | PUBMED
29. Early Treatment Diabetic Retinopathy Study Research Group. Fundus photographic risk factors for progression of diabetic retinopathy: ETDRS Report No. 12. Ophthalmology. 1991;98(5)(suppl):823-833. WEB OF SCIENCE | PUBMED
30. Poulsen MK, Henriksen JE, Hother-Nielsen O, Beck-Nielsen H. The combined effect of triple therapy with rosiglitazone, metformin, and insulin aspart in type 2 diabetic patients. Diabetes Care. 2003;26(12):3273-3279. FREE FULL TEXT
31. Aiello LP, Cahill MT, Wong JS. Systemic considerations in the management of diabetic retinopathy. Am J Ophthalmol. 2001;132(5):760-776. FULL TEXT | WEB OF SCIENCE | PUBMED
32. Avandia [package insert]. Research Triangle Park, NC: GlaxoSmithKline; 2006.
33. Haupt E, Benecke A, Haupt A, Herrmann R, Vogel H, Walter C. The KID Study VI: diabetic complications and associated diseases in younger type 2 diabetics still performing a profession: prevalence and correlation with duration of diabetic state, BMI and C-peptide. Exp Clin Endocrinol Diabetes. 1999;107(7):435-441. WEB OF SCIENCE | PUBMED
34. Manaviat MR, Afkhami M, Shoja MR. Retinopathy and microalbuminuria in type II diabetic patients. BMC Ophthalmol. 2004;4:9. http://www.biomedcentral.com/1471-2415/4/9. Accessed September 1, 2007. FULL TEXT | PUBMED
35. Pistrosch F, Herbrig K, Kindel B, Passauer J, Fischer S, Gross P. Rosiglitazone improves glomerular hyperfiltration, renal endothelial dysfunction, and microalbuminuria of incipient diabetic nephropathy in patients. Diabetes. 2005;54(7):2206-2211. FREE FULL TEXT
36. Negro R, Mangieri T, Dazzi D, Pezzarossa A, Hassan H. Rosiglitazone effects on blood pressure and metabolic parameters in nondipper diabetic patients. Diabetes Res Clin Pract. 2005;70(1):20-25. FULL TEXT | WEB OF SCIENCE | PUBMED
37. Mathiesen ER, Ronn B, Storm B, Foght H, Deckert T. The natural course of microalbuminuria in insulin-dependent diabetes: a 10-year prospective study. Diabet Med. 1995;12(6):482-487. WEB OF SCIENCE | PUBMED
38. UK Prospective Diabetes Study Group. Efficacy of atenolol and captopril in reducing risk of macrovascular and microvascular complications in type 2 diabetes: UKPDS 39. BMJ. 1998;317(7160):713-720. FREE FULL TEXT
39. Sotiropoulos KB, Clermont A, Yasuda Y; et al. Adipose-specific effect of rosiglitazone on vascular permeability and protein kinase C activation: novel mechanism for PPAR{gamma} agonist's effects on edema and weight gain. FASEB J. 2006;20(8):1203-1205. FREE FULL TEXT
40. Lebovitz HE, Kreider M, Freed MI. Evaluation of liver function in type 2 diabetic patients during clinical trials: evidence that rosiglitazone does not cause hepatic dysfunction. Diabetes Care. 2002;25(5):815-821. FREE FULL TEXT
41. Hollenberg NK. Considerations for management of fluid dynamic issues associated with thiazolidinediones. Am J Med. 2003;115(suppl 8A):111S-115S. PUBMED
42. O’Moore-Sullivan TM, Prins JB. Thiazolidinediones and type 2 diabetes: new drugs for an old disease. Med J Aust. 2002;176(8):381-386. WEB OF SCIENCE | PUBMED
43. Center for Drug Evaluation and Research, US Food and Drug Administration. Drug approval package for Avandia (rosiglitazone maleate) tablets. http://www.fda.gov/cder/foi/nda/99/21071_avandia.htm. Accessed May 2007.
44. Wysowski DK, Armstrong G, Governale L. Rapid increase in the use of oral antidiabetic drugs in the United States, 1990-2001. Diabetes Care. 2003;26(6):1852-1855. FREE FULL TEXT
45. Nissen SE, Wolski K. Effect of rosiglitazone on the risk of myocardial infarction and death from cardiovascular causes. N Engl J Med. 2007;356(24):2457-2471. FULL TEXT | PUBMED
46. Psaty BM, Furberg CD. Rosiglitazone and cardiovascular risk. N Engl J Med. 2007;356(24):2522-2524. FULL TEXT | WEB OF SCIENCE | PUBMED
47. Home PD, Pocock SJ, Beck-Nielsen H; et al. Rosiglitazone evaluated for cardiovascular outcomes: an interim analysis. N Engl J Med. 2007;357(1):28-38. FULL TEXT | PUBMED
48. Gerstein HC, Yusuf S, Bosch J; et al. Effect of rosiglitazone on the frequency of diabetes in patients with impaired glucose tolerance or impaired fasting glucose: a randomised controlled trial. Lancet. 2006;368(9541):1096-1105. FULL TEXT | PUBMED
49. Marx N, Wohrle J, Nusser T; et al. Pioglitazone reduces neointima volume after coronary stent implantation: a randomized, placebo-controlled, double-blind trial in nondiabetic patients. Circulation. 2005;112(18):2792-2798. FREE FULL TEXT


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Delicious Delicious   Add to Digg Digg   Add to Facebook Facebook   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter     What's this?

RELATED LETTERS

Association of Proliferative Diabetic Retinopathy With Insulin Use and Microalbuminuria
Shu-Hsun Chu and Ai-Hsien Li
Arch Ophthalmol. 2010;128(1):146.
EXTRACT | FULL TEXT  

Association of Proliferative Diabetic Retinopathy With Insulin Use and Microalbuminuria—Reply
Lloyd Paul Aiello and Lucy Q. Shen
Arch Ophthalmol. 2010;128(1):146-147.
EXTRACT | FULL TEXT  


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES

Lipid metabolites in the pathogenesis and treatment of neovascular eye disease
Stahl et al.
Br J Ophthalmol 2011;95:1496-1501.
ABSTRACT | FULL TEXT  

Pioglitazone, a Peroxisome Proliferator-Activated Receptor-{gamma} Agonist, Induces Dilation of Isolated Porcine Retinal Arterioles: Role of Nitric Oxide and Potassium Channels
Omae et al.
IOVS 2011;52:6749-6756.
ABSTRACT | FULL TEXT  

5-Lipoxygenase Metabolite 4-HDHA Is a Mediator of the Antiangiogenic Effect of {omega}-3 Polyunsaturated Fatty Acids
Sapieha et al.
Sci Transl Med 2011;3:69ra12-69ra12.
ABSTRACT | FULL TEXT  

Short Communication: PPAR{gamma} Mediates a Direct Antiangiogenic Effect of {omega}3-PUFAs in Proliferative Retinopathy
Stahl et al.
Circ. Res. 2010;107:495-500.
ABSTRACT | FULL TEXT  

Lack of Association Between Thiazolidinediones and Macular Edema in Type 2 Diabetes: The ACCORD Eye Substudy
Ambrosius et al.
Arch Ophthalmol 2010;128:312-318.
ABSTRACT | FULL TEXT  

Association of Proliferative Diabetic Retinopathy With Insulin Use and Microalbuminuria
Chu and Li
Arch Ophthalmol 2010;128:146-146.
FULL TEXT  

Thiazolidinediones Reduce Pathological Neovascularization in Ischemic Retina Via an Adiponectin-Dependent Mechanism
Higuchi et al.
Arterioscler. Thromb. Vasc. Bio. 2010;30:46-53.
ABSTRACT | FULL TEXT  

Association of Proliferative Diabetic Retinopathy With Insulin Use and Microalbuminuria--Reply
Aiello and Shen
Arch Ophthalmol 2010;128:146-147.
FULL TEXT  

Challenges in Understanding Diabetic Embryopathy
Loeken
Diabetes 2008;57:3187-3188.
FULL TEXT  





HOME | CURRENT ISSUE | PAST ISSUES | TOPIC COLLECTIONS | CME | PHYSICIAN JOBS | SUBMIT | SUBSCRIBE | HELP
CONDITIONS OF USE | PRIVACY POLICY | CONTACT US | SITE MAP
 
© 2008 American Medical Association. All Rights Reserved.