Lutein/zeaxanthin for the treatment of age-related cataract: AREDS2 randomized trial report no. 4

IMPORTANCE

Age-related cataract is a leading cause of visual impairment in the United States. The prevalence of age-related cataract is increasing, with an estimated 30.1 million Americans likely to be affected by 2020.

OBJECTIVE

To determine whether daily oral supplementation with lutein/zeaxanthin affects the risk for cataract surgery.

DESIGN, SETTING, AND PATIENTS

The Age-Related Eye Disease Study 2 (AREDS2), a multicenter, double-masked clinical trial, enrolled 4203 participants, aged 50 to 85 years, at risk for progression to advanced age-related macular degeneration.

INTERVENTIONS

Participants were randomly assigned to daily placebo; lutein/zeaxanthin, 10mg/2mg; omega-3 long-chain polyunsaturated fatty acids, 1 g; or a combination to evaluate the effects on the primary outcome of progression to advanced age-related macular degeneration.

MAIN OUTCOMES AND MEASURES

Cataract surgery was documented at annual study examination with the presence of pseudophakia or aphakia, or reported during telephone calls at 6-month intervals between study visits. Annual best-corrected visual acuity testing was performed. A secondary outcome of AREDS2 was to evaluate the effects of lutein/zeaxanthin on the subsequent need for cataract surgery.

RESULTS

A total of 3159 AREDS2 participants were phakic in at least 1 eye and 1389 of 6027 study eyes underwent cataract surgery during the study, with median follow-up of 4.7 years. The 5-year probability of progression to cataract surgery in the no lutein/zeaxanthin group was 24%. For lutein/zeaxanthin vs no lutein/zeaxanthin, the hazard ratios for progression to cataract surgery was 0.96 (95% CI, 0.84-1.10; P = .54). For participants in the lowest quintile of dietary intake of lutein/zeaxanthin, the hazard ratio comparing lutein/zeaxanthin vs no lutein/zeaxanthin for progression to cataract surgery was 0.68 (95% CI, 0.48-0.96; P = .03). The hazard ratio for 3 or more lines of vision loss was 1.03 (95% CI, 0.93-1.13; P = .61 for lutein/zeaxanthin vs no lutein/zeaxanthin).

CONCLUSIONS AND RELEVANCE

Daily supplementation with lutein/zeaxanthin had no statistically significant overall effect on rates of cataract surgery or vision loss.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00345176.

Evaluation of optimized digital fundus reflex photographs for lens opacities in the age-related eye disease study 2: AREDS2 report 7

PURPOSE

We described the system for grading lens opacities using stereoscopic digital fundus reflex photographs in the Age-Related Eye Disease Study 2 (AREDS2) and compared reproducibility with the AREDS lens grading system, which used retroillumination film images.

METHODS

Stereoscopic fundus reflex photographs were acquired in a standardized fashion at baseline and annually. Images were enhanced and evaluated in the red channel at a central reading center. Percentage involvement of cortical and posterior subcapsular (PSC) lens opacities within the central 5 mm diameter zone of a modified AREDS lens grid was estimated. Reproducibility was assessed for contemporaneous variability (ongoing, monthly regrade on 5% of submissions, n = 777 eyes) and temporal drift (regrading a subset of baseline photographs annually, n = 88).

RESULTS

In the contemporaneous exercise, the agreement for presence of cortical opacities was 93% (κ = 0.86) and for PSC opacities it was 97% (κ = 0.83). Intraclass correlation (ICC) for area of central zone involvement was 0.95 for cortical and 0.99 for PSC opacities. Historic data for contemporaneous regrading of film-based images in AREDS showed an ICC of 0.94 for cortical and 0.82 for PSC. The final annual temporal drift exercise had a reproducibility of 95% for cortical and PSC opacities.

CONCLUSIONS

Digital grading using fundus reflex images with image enhancing tools has reproducibility comparable to film-based retroillumination images, and may be useful for centralized objective lens opacity assessment in clinical trials using widely available fundus cameras. Red reflex images limit evaluation to cortical and PSC opacities, and do not permit assessment of nuclear opacities. (ClinicalTrials.gov number, NCT00345176.).

Methods and reproducibility of grading optimized digital color fundus photographs in the Age-Related Eye Disease Study 2 (AREDS2 Report Number 2)

PURPOSE

To establish continuity with the grading procedures and outcomes from the historical data of the Age-Related Eye Disease Study (AREDS), color photographic imaging and evaluation procedures for the assessment of age-related macular degeneration (AMD) were modified for digital imaging in the AREDS2. The reproducibility of the grading of index AMD lesion components and for the AREDS severity scale was tested at the AREDS2 reading center.

METHODS

Digital color stereoscopic fundus photographs from 4203 AREDS2 subjects collected at baseline and annual follow-up visits were optimized for tonal balance and graded according to a standard protocol slightly modified from AREDS. The reproducibility of digital grading of AREDS2 images was assessed by reproducibility exercises, temporal drift (regrading a subset of baseline annually, n = 88), and contemporaneous masked regrading (ongoing, monthly regrade on 5% of submissions, n = 1335 eyes).

RESULTS

In AREDS2, 91% and 96% of images received replicate grades within two steps of the baseline value on the AREDS severity scale for temporal drift and contemporaneous assessment, respectively (weighted Kappa of 0.73 and 0.76). Historical data for temporal drift in replicate gradings on the AREDS film-based images were 88% within two steps (weighted Kappa = 0.88). There was no difference in AREDS2-AREDS concordance for temporal drift (exact P = 0.57).

CONCLUSIONS

Digital color grading has nearly the same reproducibility as historical film grading. There is substantial agreement for testing the predictive utility of the AREDS severity scale in AREDS2 as a clinical trial outcome. (ClinicalTrials.gov number, NCT00345176.)

Ten-year incidence rates of age-related cataract in the Age-Related Eye Disease Study (AREDS): AREDS report no. 33

PURPOSE

To investigate the long-term incidence of age-related cataract and cataract surgery in the Age-Related Eye Disease Study (AREDS) cohort.

METHODS

Baseline and annual lens photographs of participants, aged 55-80 years, were graded centrally for nuclear, cortical, and posterior subcapsular (PSC) lens opacities using the AREDS System for Classifying Cataracts. Progression from a baseline status of no or mild lens opacity to at least moderate severity was analyzed and cumulative incidence estimated rates were calculated for each lens opacity type and cataract surgery stratified by age, sex, race, age-related macular degeneration category, multivitamin (Centrum) use and history of diabetes.

RESULTS

The ten-year cumulative incidence was 43.6% for any cataract, 23.1% for nuclear cataract, 22.0% for cortical cataract, 13.1% for PSC cataract, and 26.8% for cataract surgery. The 5- and 10-year incidence rates of all cataract types and cataract surgery were significantly higher with increasing age. Females had a higher incidence of any, nuclear and cortical cataract and cataract surgery (p = 0.02-0.05). Incidence of cortical cataract was higher in non-white participants (p = 0.001).

CONCLUSIONS

These results are largely consistent with the results of previous observational studies. Long-term incidence rates of type-specific cataract can be useful in designing clinical studies of age-related cataract.

Treatment of geographic atrophy with subconjunctival sirolimus: results of a phase I/II clinical trial

PURPOSE

To investigate the safety and effects of subconjunctival sirolimus, an mTOR inhibitor and immunosuppressive agent, for the treatment of geographic atrophy (GA).

METHODS

The study was a single-center, open-label phase II trial, enrolling 11 participants with bilateral GA; eight participants completed 24 months of follow-up. Sirolimus (440 μg) was administered every 3 months as a subconjunctival injection in only one randomly assigned eye in each participant for 24 months. Fellow eyes served as untreated controls. The primary efficacy outcome measure was the change in the total GA area at 24 months. Secondary outcomes included changes in visual acuity, macular sensitivity, central retinal thickness, and total drusen area.

RESULTS

The study drug was well tolerated with few symptoms and related adverse events. Study treatment in study eyes was not associated with structural or functional benefits relative to the control fellow eyes. At month 24, mean GA area increased by 54.5% and 39.7% in study and fellow eyes, respectively (P = 0.41), whereas mean visual acuity decreased by 21.0 letters and 3.0 letters in study and fellow eyes, respectively (P = 0.03). Substantial differences in mean changes in drusen area, central retinal thickness, and macular sensitivity were not detected for all analysis time points up to 24 months.

CONCLUSIONS

Repeated subconjunctival sirolimus was well-tolerated in patients with GA, although no positive anatomic or functional effects were identified. Subconjunctival sirolimus may not be beneficial in the prevention of GA progression, and may potentially be associated with effects detrimental to visual acuity. (ClinicalTrials.gov number, NCT00766649.).

Hypomethylation of the IL17RC promoter associates with age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in the elderly population worldwide. Although recent studies have demonstrated strong genetic associations between AMD and SNPs in a number of genes, other modes of regulation are also likely to play a role in the etiology of this disease. We identified a significantly decreased level of methylation on the IL17RC promoter in AMD patients. Furthermore, we showed that hypomethylation of the IL17RC promoter in AMD patients led to an elevated expression of its protein and messenger RNA in peripheral blood as well as in the affected retina and choroid, suggesting that the DNA methylation pattern and expression of IL17RC may potentially serve as a biomarker for the diagnosis of AMD and likely plays a role in disease pathogenesis.

The Age-Related Eye Disease Study 2 (AREDS2): study design and baseline characteristics (AREDS2 report number 1)

PURPOSE

The Age-Related Eye Disease Study (AREDS) demonstrated beneficial effects of oral supplementation with antioxidant vitamins and minerals on the development of advanced age-related macular degeneration (AMD) in persons with at least intermediate AMD (bilateral large drusen with or without pigment changes). Observational data suggest that other oral nutrient supplements might further reduce the risk of progression to advanced AMD. The primary purpose of the Age-Related Eye Disease Study 2 (AREDS2) is to evaluate the efficacy and safety of lutein plus zeaxanthin (L+Z) and/or ω-3 long-chain polyunsaturated fatty acid (LCPUFA) supplementation in reducing the risk of developing advanced AMD. The study also assesses the reduction in zinc and the omission of β-carotene from original AREDS formulation.

DESIGN

Multicenter, phase III, randomized, controlled clinical trial.

PARTICIPANTS

Persons aged 50 to 85 with bilateral intermediate AMD or advanced AMD in 1 eye.

METHODS

All participants were randomly assigned to placebo (n = 1012), L+Z (10 mg/2 mg; n = 1044), ω-3 LCPUFAs (eicosapentaenoic acid + docosahexaenoic acid [650 mg/350 mg]; n = 1069), or the combination of L+Z and ω-3 LCPUFAs (n = 1078). All participants were offered a secondary randomization to 1 of 4 variations of the original AREDS formulation keeping vitamins C (500 mg) and E (400 IU) and copper (2 mg) unchanged while varying zinc and β-carotene as follows: Zinc remains at the original level (80 mg), lower only zinc to 25 mg, omit β-carotene only, or lower zinc to 25 mg and omit β-carotene.

MAIN OUTCOME MEASURES

Progression to advanced AMD determined by centralized grading of annual fundus photographs.

RESULTS

We enrolled 4203 participants at 82 clinical centers located in the United States. Population characteristics at baseline were as follows: Mean age, 74 years; 57% female; 97% white; 7% current smokers; 19% with prior cardiovascular disease; and 44% and 50% taking statin-class cholesterol-lowering drugs and aspirin, respectively. Ocular characteristics include 59% with bilateral large drusen, 32% with advanced AMD in 1 eye and mean visual acuity of 20/32 in eyes without advanced AMD.

CONCLUSIONS

This report presents the AREDS2 study design and the participants' baseline demographic and ocular characteristics.

Ranibizumab and bevacizumab for treatment of neovascular age-related macular degeneration: two-year results

OBJECTIVE

To describe effects of ranibizumab and bevacizumab when administered monthly or as needed for 2 years and to describe the impact of switching to as-needed treatment after 1 year of monthly treatment.

DESIGN

Multicenter, randomized clinical trial.

PARTICIPANTS

Patients (n = 1107) who were followed up during year 2 among 1185 patients with neovascular age-related macular degeneration who were enrolled in the clinical trial.

INTERVENTIONS

At enrollment, patients were assigned to 4 treatment groups defined by drug (ranibizumab or bevacizumab) and dosing regimen (monthly or as needed). At 1 year, patients initially assigned to monthly treatment were reassigned randomly to monthly or as-needed treatment, without changing the drug assignment.

MAIN OUTCOME MEASURES

Mean change in visual acuity.

RESULTS

Among patients following the same regimen for 2 years, mean gain in visual acuity was similar for both drugs (bevacizumab-ranibizumab difference, -1.4 letters; 95% confidence interval [CI], -3.7 to 0.8; P = 0.21). Mean gain was greater for monthly than for as-needed treatment (difference, -2.4 letters; 95% CI, -4.8 to -0.1; P = 0.046). The proportion without fluid ranged from 13.9% in the bevacizumab-as-needed group to 45.5% in the ranibizumab monthly group (drug, P = 0.0003; regimen, P < 0.0001). Switching from monthly to as-needed treatment resulted in greater mean decrease in vision during year 2 (-2.2 letters; P = 0.03) and a lower proportion without fluid (-19%; P < 0.0001). Rates of death and arteriothrombotic events were similar for both drugs (P > 0.60). The proportion of patients with 1 or more systemic serious adverse events was higher with bevacizumab than ranibizumab (39.9% vs. 31.7%; adjusted risk ratio, 1.30; 95% CI, 1.07-1.57; P = 0.009). Most of the excess events have not been associated previously with systemic therapy targeting vascular endothelial growth factor (VEGF).

CONCLUSIONS

Ranibizumab and bevacizumab had similar effects on visual acuity over a 2-year period. Treatment as needed resulted in less gain in visual acuity, whether instituted at enrollment or after 1 year of monthly treatment. There were no differences between drugs in rates of death or arteriothrombotic events. The interpretation of the persistence of higher rates of serious adverse events with bevacizumab is uncertain because of the lack of specificity to conditions associated with inhibition of VEGF.

Rationale for the diabetic retinopathy clinical research network treatment protocol for center-involved diabetic macular edema

OBJECTIVE

To describe the underlying principles used to develop a web-based algorithm that incorporated intravitreal anti-vascular endothelial growth factor (anti-VEGF) treatment for diabetic macular edema (DME) in a Diabetic Retinopathy Clinical Research Network (DRCR.net) randomized clinical trial.

DESIGN

Discussion of treatment protocol for DME.

PARTICIPANTS

Subjects with vision loss resulting from DME involving the center of the macula.

METHODS

The DRCR.net created an algorithm incorporating anti-VEGF injections in a comparative effectiveness randomized clinical trial evaluating intravitreal ranibizumab with prompt or deferred (≥24 weeks) focal/grid laser treatment in eyes with vision loss resulting from center-involved DME. Results confirmed that intravitreal ranibizumab with prompt or deferred laser provides superior visual acuity outcomes compared with prompt laser alone through at least 2 years. Duplication of this algorithm may not be practical for clinical practice. To share their opinion on how ophthalmologists might emulate the study protocol, participating DRCR.net investigators developed guidelines based on the algorithm's underlying rationale.

MAIN OUTCOME MEASURES

Clinical guidelines based on a DRCR.net protocol.

RESULTS

The treatment protocol required real-time feedback from a web-based data entry system for intravitreal injections, focal/grid laser treatment, and follow-up intervals. Guidance from this system indicated whether treatment was required or given at investigator discretion and when follow-up should be scheduled. Clinical treatment guidelines, based on the underlying clinical rationale of the DRCR.net protocol, include repeating treatment monthly as long as there is improvement in edema compared with the previous month or until the retina is no longer thickened. If thickening recurs or worsens after discontinuing treatment, treatment is resumed.

CONCLUSIONS

Duplication of the approach used in the DRCR.net randomized clinical trial to treat DME involving the center of the macula with intravitreal ranibizumab may not be practical in clinical practice, but likely can be emulated based on an understanding of the underlying rationale for the study protocol. Inherent differences between a web-based treatment algorithm and a clinical approach may lead to differences in outcomes that are impossible to predict. The closer the clinical approach is to the algorithm used in the study, the more likely the outcomes will be similar to those published.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Risk factors associated with incident cataracts and cataract surgery in the Age-related Eye Disease Study (AREDS): AREDS report number 32

OBJECTIVE

To investigate potential risk factors associated with incident nuclear, cortical, and posterior subcapsular (PSC) cataracts and cataract surgery in participants in the Age-Related Eye Disease Study (AREDS).

DESIGN

Clinic-based prospective cohort study.

PARTICIPANTS

Persons (n = 4425) 55 to 80 years of age enrolled in a controlled clinical trial of antioxidant vitamins and minerals, AREDS, for age-related macular degeneration and cataract.

METHODS

Lens photographs were graded centrally for nuclear, cortical, and PSC opacities using the AREDS system for classifying cataracts. Type-specific incident cataracts were defined as an increase in cataract grade from none or mild at baseline to a grade of moderate at follow-up, also with a grade of at least moderate at the final visit, or cataract surgery. Cox regression analyses were used to assess baseline risk factors associated with type-specific opacities and cataract surgery.

MAIN OUTCOME MEASURES

Moderate cataract was defined as a grade of 4.0 or more for nuclear opacity, 10% or more involvement within the full visible lens for cortical opacity, and 5% or more involvement of the central 5-mm circle of the lens for PSC opacity. These were graded on baseline and annual lens photographs.

RESULTS

A clinic-based cohort of 4425 persons 55 to 80 years of age at baseline was followed up for an average of 9.8±2.4 years. The following associations were found: increasing age with increased risk of all types of cataract and cataract surgery; males with increased risk of PSC and decreased risk of cortical cataracts; nonwhite persons with increased risk of cortical cataract; hyperopia with decreased risk of PSC, nuclear cataract, and cataract surgery; Centrum (Wyeth Consumer Healthcare, Madison, NJ) use with decreased risk of nuclear cataract; diabetes with increased risk of cortical, PSC cataract, and cataract surgery; higher educational level with decreased risk of cortical cataract; and smoking with increased risk of cortical cataract and cataract surgery. Estrogen replacement therapy in female participants increased the risk of cataract surgery.

CONCLUSIONS

These findings largely are consistent with the results of previous studies, providing further evidence for possible modifiable risk factors for age-related cataract.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Risk assessment model for development of advanced age-related macular degeneration

OBJECTIVE

To design a risk assessment model for development of advanced age-related macular degeneration (AMD) incorporating phenotypic, demographic, environmental, and genetic risk factors.

METHODS

We evaluated longitudinal data from 2846 participants in the Age-Related Eye Disease Study. At baseline, these individuals had all levels of AMD, ranging from none to unilateral advanced AMD (neovascular or geographic atrophy). Follow-up averaged 9.3 years. We performed a Cox proportional hazards analysis with demographic, environmental, phenotypic, and genetic covariates and constructed a risk assessment model for development of advanced AMD. Performance of the model was evaluated using the C statistic and the Brier score and externally validated in participants in the Complications of Age-Related Macular Degeneration Prevention Trial.

RESULTS

The final model included the following independent variables: age, smoking history, family history of AMD (first-degree member), phenotype based on a modified Age-Related Eye Disease Study simple scale score, and genetic variants CFH Y402H and ARMS2 A69S. The model did well on performance measures, with very good discrimination (C statistic = 0.872) and excellent calibration and overall performance (Brier score at 5 years = 0.08). Successful external validation was performed, and a risk assessment tool was designed for use with or without the genetic component.

CONCLUSIONS

We constructed a risk assessment model for development of advanced AMD. The model performed well on measures of discrimination, calibration, and overall performance and was successfully externally validated. This risk assessment tool is available for online use.

Expanded 2-year follow-up of ranibizumab plus prompt or deferred laser or triamcinolone plus prompt laser for diabetic macular edema

OBJECTIVE

To report expanded 2-year follow-up of a previously reported randomized trial evaluating intravitreal 0.5 mg ranibizumab or 4 mg triamcinolone combined with focal/grid laser compared with focal/grid laser alone for treatment of diabetic macular edema (DME).

DESIGN

Multicenter, randomized clinical trial.

PARTICIPANTS

A total of 854 study eyes of 691 participants with visual acuity of 20/32 to 20/320 (approximate Snellen equivalent) and DME involving the fovea.

METHODS

Continuation of procedures previously reported for the randomized trial.

MAIN OUTCOME MEASURES

Best-corrected visual acuity and safety at the 2-year visit.

RESULTS

At the 2-year visit, compared with the sham + prompt laser group, the mean change in the visual acuity letter score from baseline was 3.7 letters greater in the ranibizumab + prompt laser group (95% confidence interval adjusted for multiple comparisons [aCI], -0.4 to +7.7), 5.8 letters greater in the ranibizumab + deferred laser group (95% aCI, +1.9 to +9.8), and 1.5 letters worse in the triamcinolone + prompt laser group (95% aCI, -5.5 to +2.4). After the 1- to 2-year visit in the ranibizumab + prompt or deferred laser groups, the median numbers of injections were 2 and 3 (potential maximum of 13), respectively. At the 2-year visit, the percentages of eyes with central subfield thickness ≥250 μm were 59% in the sham + prompt laser group, 43% in the ranibizumab + prompt laser group, 42% in the ranibizumab + deferred laser group, and 52% in the triamcinolone + prompt laser group. No systemic events attributable to study treatment were apparent. Three eyes in 3 (0.8%) of 375 participants had injection-related endophthalmitis in the ranibizumab groups, whereas elevated intraocular pressure and cataract surgery were more frequent in the triamcinolone + prompt laser group.

CONCLUSIONS

The expanded 2-year results reported are similar to results published previously and reinforce the conclusions originally reported: Ranibizumab should be considered for patients with DME and characteristics similar to those of the cohort in this clinical trial, including vision impairment with DME involving the center of the macula.

Copy number variations in candidate genes in neovascular age-related macular degeneration

PURPOSE

The pathogenesis of age-related macular degeneration (AMD) is strongly influenced by genetic factors, and single nucleotide polymorphisms have been consistently linked to AMD. Copy number variation (CNV), or variation in the number of copies of a particular segment of DNA, may also contribute to AMD pathogenesis. This study evaluated CNVs in candidate genes that have been reported to be linked to AMD.

METHODS

Study participants were 131 patients with neovascular AMD and 103 elderly persons without AMD who were evaluated by retinal specialists at the National Eye Institute. DNA was collected from peripheral whole blood, and duplex RT-PCR based copy number (CN) assays were performed for the genes CCR3, CFH, CX3CR1, ERCC6, HTRA1, and VEGF. Quantitative CNs (CN = 0, 1, 2, or 3+) were determined.

RESULTS

Novel CNVs were discovered in CCR3, CX3CR1, and ERCC6. The unadjusted data suggested that CN = 3+ for CX3CR1 might be mildly protective against AMD, but this trend did not persist after adjustment for age. AMD patients appeared to have an elevated mean CFH CN relative to controls (2.13 [95% confidence interval (CI), 2.05-2.21] vs. 2.01 [95% CI, 1.92-2.09 copies]; P = 0.05). No significant associations between CNV and AMD were observed for the remaining genes.

CONCLUSIONS

The methods described are suitable for quantitative characterization of CNV in candidate genes. The authors identified CNVs in AMD-associated genes but did not find strong evidence for a link with neovascular AMD.

Changes in retinal sensitivity in geographic atrophy progression as measured by microperimetry

PURPOSE

To characterize changes in macular sensitivity during geographic atrophy (GA) progression using microperimetry.

METHODS

Retinal sensitivity in the macular area was evaluated by microperimetry in 10 patients with bilateral GA, with adequate data obtained in 9 of 10 patients (n = 18 eyes). Patients had been enrolled in an interventional trial in which one eye had been randomized to treatment and the other eye observed. No treatment effect with regard to GA growth and microperimetric measurements was detected, and all eyes were analyzed. Microperimetric assessments of the central 20° of the macula were performed every 6 months over 24 months. Parameters analyzed included number of scotomatous points, mean retinal sensitivity of responding points, and fixation stability. Autofluorescence imaging and fundus photography were also obtained.

RESULTS

Microperimetric parameters demonstrated statistically significant changes as a function of time. Mean number of scotomatous points increased significantly with time (P = 0.004) at a rate of 4.4 points/year. Mean retinal sensitivities of all points, all responding points, and all perilesional points all decreased significantly with time (P < 0.003), as did fixation quality within the 2° and 4° circles (P < 0.002). The growth of GA lesion area was associated with the changes in the number of scotomatous points (P = 0.01) but not with changes in the other microperimetric parameters.

CONCLUSIONS

Macular sensitivity and fixation quality undergo progressive change during the GA progression, reflecting alterations in macular function extending beyond the GA lesion proper. Microperimetric measurements may provide useful functional outcome measures for the clinical study of GA.

Prevalence of posterior subcapsular cataracts in volunteer cytapheresis donors

BACKGROUND

Granulocyte donors routinely receive dexamethasone orally before donation. Steroids may increase the risk of posterior subcapsular cataract (PSC) formation.

STUDY DESIGN AND METHODS

We recruited 100 granulocyte donors (four or more granulocyte donations; any number of platelet [PLT] donations) and 100 age- and sex-matched PLT donors (zero to three granulocyte donations, any number of PLT donations) to examine the risk of PSC. PSC was assessed by a masked ophthalmologist and reading center lens photograph gradings or medical record documentation of PSC as the reason for cataract extraction.

RESULTS

Fourteen eyes of 10 granulocyte donors and five eyes of four PLT donors had PSCs (odds ratio [OR], 2.82; 95% confidence interval [CI], 0.83-9.61; p = 0.10). Risk of PSC increased with number of granulocyte donations: compared to zero to three donations (4.0%), the risk for four to nine, 10 to 19, and 20 or more donations was 8.6% (OR, 2.25; 95% CI, 0.31-13.99; p = 0.30), 9.5% (OR, 2.53; 95% CI, 0.44-14.20; p = 0.21), and 13.0% (OR, 3.60; 95% CI, 0.48-22.81; p = 0.11), respectively (p = 0.06 for trend).

CONCLUSION

We did not demonstrate a statistically significant increased risk of PSC associated with granulocyte donation. However, although this makes a large risk unlikely, we cannot rule out a small to moderate risk and there is biologic plausibility that the steroid administration associated with granulocyte donation could be associated with PSC formation. Transfusion medicine professionals should advise granulocyte apheresis donors to maintain an appropriate frequency of eye examinations.

Treatment of geographic atrophy by the topical administration of OT-551: results of a phase II clinical trial

PURPOSE

To investigate the safety and preliminary efficacy of OT-551, a disubstituted hydroxylamine with antioxidant properties, for the treatment of geographic atrophy (GA), the advanced atrophic form of age-related macular degeneration (AMD).

METHODS

The study was a single-center, open-label phase II trial, enrolling 10 participants with bilateral GA. Topical 0.45% OT-551 was administered in one randomly assigned eye three times daily for 2 years. Safety measures were assessed by complete ophthalmic examination, fundus photography, and review of symptoms. The primary efficacy outcome measure was the change in best corrected visual acuity at 24 months. Secondary efficacy measures included changes in area of GA, contrast sensitivity, microperimetry measurements, and total drusen area from baseline.

RESULTS

Study drug was well tolerated and was associated with few adverse events. The mean change in BCVA at 2 years was +0.2 ± 13.3 letters in the study eyes and -11.3 ± 7.6 letters in fellow eyes (P = 0.0259). However, no statistically significant differences were found between the study and fellow eyes for all other secondary outcome measures.

CONCLUSIONS

OT-551 was well tolerated by study participants and was not associated with any serious adverse effects. Efficacy measurements in this small study indicate a possible effect in maintaining visual acuity. However, the absence of significant effects on other outcomes measures in this study suggests that OT-551, in the current concentration and mode of delivery, may have limited or no benefit as a treatment for GA (ClinicalTrials.gov number, NCT00306488).

Evaluation of the age-related eye disease study clinical lens grading system AREDS report No. 31

PURPOSE

To examine the grading (interrater) reliability of the Age-Related Eye Disease Study (AREDS) Clinical Lens Grading System (ARLNS).

DESIGN

Evaluation of diagnostic test or technology.

PARTICIPANTS

One hundred fifty volunteers (284 eyes).

METHODS

Participants with lens opacities of varying severity were independently graded at the slit lamp for cataract severity by 2 examiners (retinal or anterior segment specialists) using the ARLNS, which employs 3 standard photographs of increasing severity for classifying each of the 3 major types of opacity. Lens photographs were taken and graded at a reading center using the more detailed AREDS System for Classifying Cataracts from photographs.

MAIN OUTCOME MEASURES

The Pearson correlation, weighted-kappa, and limits-of-agreement statistics were used to assess the interrater agreement of the gradings.

RESULTS

Examinations were performed on 284 lenses (150 participants). Tests of interrater reliability between pairs of clinicians showed substantial agreement between clinicians for cortical and posterior subcapsular opacities and moderate agreement for nuclear opacities. A similar pattern and strength of agreement was present when comparing scores of retinal versus anterior segment specialists. Interrater agreement between clinical and reading center gradings was not as great as inter-clinician agreement.

CONCLUSIONS

Interrater agreements were in the moderate to substantial range for the clinical assessment of lens opacities. Inherent differences in cataract classification systems that rely on slit lamp vs photographic assessments of lens opacities may explain some of the disagreement noted between slit lamp and photographic gradings. Given the interrater reliability statistics for clinicians and the simplicity of the grading procedure, ARLNS is presented for use in studies requiring a simple, inexpensive method for detecting the presence and severity of the major types of lens opacities.

FINANCIAL DISCLOSURE(S)

The authors have no proprietary or commercial interest in any of the materials discussed in this article.

Randomized trial evaluating ranibizumab plus prompt or deferred laser or triamcinolone plus prompt laser for diabetic macular edema

OBJECTIVE

Evaluate intravitreal 0.5 mg ranibizumab or 4 mg triamcinolone combined with focal/grid laser compared with focal/grid laser alone for treatment of diabetic macular edema (DME).

DESIGN

Multicenter, randomized clinical trial.

PARTICIPANTS

A total of 854 study eyes of 691 participants with visual acuity (approximate Snellen equivalent) of 20/32 to 20/320 and DME involving the fovea.

METHODS

Eyes were randomized to sham injection + prompt laser (n=293), 0.5 mg ranibizumab + prompt laser (n=187), 0.5 mg ranibizumab + deferred (> or =24 weeks) laser (n=188), or 4 mg triamcinolone + prompt laser (n=186). Retreatment followed an algorithm facilitated by a web-based, real-time data-entry system.

MAIN OUTCOME MEASURES

Best-corrected visual acuity and safety at 1 year.

RESULTS

The 1-year mean change (+/-standard deviation) in the visual acuity letter score from baseline was significantly greater in the ranibizumab + prompt laser group (+9+/-11, P<0.001) and ranibizumab + deferred laser group (+9+/-12, P<0.001) but not in the triamcinolone + prompt laser group (+4+/-13, P=0.31) compared with the sham + prompt laser group (+3+/-13). Reduction in mean central subfield thickness in the triamcinolone + prompt laser group was similar to both ranibizumab groups and greater than in the sham + prompt laser group. In the subset of pseudophakic eyes at baseline (n=273), visual acuity improvement in the triamcinolone + prompt laser group appeared comparable to that in the ranibizumab groups. No systemic events attributable to study treatment were apparent. Three eyes (0.8%) had injection-related endophthalmitis in the ranibizumab groups, whereas elevated intraocular pressure and cataract surgery were more frequent in the triamcinolone + prompt laser group. Two-year visual acuity outcomes were similar to 1-year outcomes.

CONCLUSIONS

Intravitreal ranibizumab with prompt or deferred laser is more effective through at least 1 year compared with prompt laser alone for the treatment of DME involving the central macula. Ranibizumab as applied in this study, although uncommonly associated with endophthalmitis, should be considered for patients with DME and characteristics similar to those in this clinical trial. In pseudophakic eyes, intravitreal triamcinolone + prompt laser seems more effective than laser alone but frequently increases the risk of intraocular pressure elevation.

Preliminary assessment of celecoxib and microdiode pulse laser treatment of diabetic macular edema

PURPOSE

Inflammation may play an important role in the pathogenesis of diabetic macular edema, a major cause of vision loss in persons with diabetes. The purpose of this study was to evaluate combined antiinflammatory therapy and laser approaches for treating patients with diabetic macular edema.

METHODS

In this prospective, factorial, randomized, multicenter trial, we compared cyclo-oxygenase-2 inhibitor (celecoxib) with placebo and diode grid laser with standard Early Treatment Diabetic Retinopathy Study focal laser treatment in 86 participants with diabetic macular edema. The primary outcome is change in visual acuity of > or = 15 letters from baseline, and the secondary outcomes include a 50% reduction in the retinal thickening of diabetic macular edema measured by optical coherence tomography and a 50% reduction in leakage severity on fluorescein angiography.

RESULTS

Visual acuity and retinal thickening data from >2 years of follow-up did not show evidence of differences between the medical and laser treatments. However, participants assigned to the celecoxib group were more likely to have a reduction in fluorescein leakage when compared with the placebo group (odds ratio = 3.6; P < 0.01).

CONCLUSION

This short-term study did not find large visual function benefits of treatment with celecoxib or diode laser compared with those of standard laser treatment. A suggestive effect of celecoxib in reducing fluorescein leakage was observed.

Change in area of geographic atrophy in the Age-Related Eye Disease Study: AREDS report number 26

OBJECTIVE

To characterize progression of geographic atrophy (GA) associated with age-related macular degeneration in AREDS as measured by digitized fundus photographs.

METHODS

Fundus photographs from 181 of 4757 AREDS participants with a GA area of at least 0.5 disc areas at baseline or from participants who developed bilateral GA during follow-up were scanned, digitized, and evaluated longitudinally. Geographic atrophy area was determined using planimetry. Rates of progression from noncentral to central GA and of vision loss following development of central GA included the entire AREDS cohort.

RESULTS

Median initial lesion size was 4.3 mm(2). Average change in digital area of GA from baseline was 2.03 mm(2) (standard error of the mean, 0.24 mm(2)) at 1 year, 3.78 mm(2) (0.24 mm(2)) at 2 years, 5.93 mm(2) (0.34 mm(2)) at 3 years, and 1.78 mm(2) (0.086 mm(2)) per year overall. Median time to developing central GA after any GA diagnosis was 2.5 years (95% confidence interval, 2.0-3.0). Average visual acuity decreased by 3.7 letters at first documentation of central GA, and by 22 letters at year 5.

CONCLUSIONS

Growth of GA area can be reliably measured using standard fundus photographs that are digitized and subsequently graded at a reading center. Development of GA is associated with subsequent further growth of GA, development of central GA, and loss in central vision.

Visual acuity outcomes after cataract surgery in patients with age-related macular degeneration: age-related eye disease study report no. 27

OBJECTIVE

To evaluate visual acuity outcomes after cataract surgery in patients with varying degrees of age-related macular degeneration (AMD).

DESIGN

Cohort study.

PARTICIPANTS

A total of 4757 participants enrolled in the Age-Related Eye Disease Study (AREDS), a prospective, multicenter, epidemiological study of the clinical course of cataract and AMD and a randomized controlled trial of antioxidants and minerals.

METHODS

Standardized lens and fundus photographs, performed at baseline and annual visits, were graded by a centralized reading center using standardized protocols for severity of AMD and lens opacities. History of cataract surgery was obtained every 6 months. Analyses were conducted using multivariate logistic regression.

MAIN OUTCOME MEASURE

The change in best-corrected visual acuity (BCVA) after cataract surgery compared with preoperative BCVA.

RESULTS

Visual acuity results were analyzed for 1939 eyes that had cataract surgery during AREDS. The mean time from cataract surgery to measurement of postoperative BCVA was 6.9 months. After adjustment for age at surgery, gender, type, and severity of cataract, the mean change in visual acuity at the next study visit after the cataract surgery was as follows: Eyes without AMD gained 8.4 letters of acuity (P<0.0001), eyes with mild AMD gained 6.1 letters of visual acuity (P<0.0001), eyes with moderate AMD gained 3.9 letters (P<0.0001), and eyes with advanced AMD gained 1.9 letters (P = 0.04). The statistically significant gain in visual acuity after cataract surgery was maintained an average of 1.4 years after cataract surgery.

CONCLUSIONS

On average, participants with varying severity of AMD benefited from cataract surgery with an increase in visual acuity postoperatively. This average gain in visual acuity persisted for at least 18 months.

Toll-like receptor polymorphisms and age-related macular degeneration: replication in three case-control samples

PURPOSE

Innate immunity appears to play a key role in age-related macular degeneration (AMD). Although two previous studies reported that gene variations in Toll-like receptor (TLR)-3 and -4 are associated with AMD, other studies have not confirmed these associations. In this study, three independent samples (two U.S. clinic-based case-control study samples and one Australian population-based study sample) were used to further assess the association of the polymorphisms rs3775291 in TLR3 and rs4986790 in TLR4 with AMD.

METHODS

AMD cases and unrelated controls were collected from the National Eye Institute Clinical Center (NEI, n = 320), the Age-Related Eye Disease Study (AREDS, n = 483), and the Blue Mountains Eye Study (BMES, n = 852). DNA extracted from subjects was genotyped for rs3775291 and rs4986790, and the associations with AMD were investigated.

RESULTS

Neither of the two polymorphisms rs3775291 and rs4986790 had a statistically significant association with AMD in any of the three sample sets or in combinations of the sets. Analysis of the combined geographic atrophy or neovascular AMD cases in the NEI, AREDS, and BMES sample sets also failed to demonstrate statistically significant associations of those two single nucleotide polymorphisms with advanced AMD.

CONCLUSIONS

Even with previously verified samples sets and adequate study powers, the results did not confirm the reported associations of TLR3 rs3775291 and TLR4 rs4986790 with AMD in the three independent samples, individually or combined.

Effects of multivitamin/mineral supplementation on plasma levels of nutrients. Report No. 4 of the Italian-American clinical trial of nutritional supplements and age-related cataract

The use of multivitamin-mineral supplements has become increasingly common, but whether the use of such supplements improves micronutrient status remains still unclear. The objective of this report is to investigate how a long-term vitamin-mineral supplementation following the US Recommended Daily Intake (RDI) affected the plasma levels of selected nutrients in a subset (No. = 407) of participants in the Italian-American Clinical Trial of Nutritional Supplements and Age-related Cataract (CTNS). The CTNS was a double-blind, single centre, controlled clinical trial of 1020 participants aged 55-75 years randomized to a daily tablet of Centrum(R) or placebo. A representative sample of 40% of the 1020 subjects, whom plasma level of selected vitamins was determined at the baseline, was retested throughout the treatment period that averaged 9.0 +/- 2.4 years. Participants assigned to Centrum(R) showed a significant increase (p < 0.005) in mean/median plasma levels of vitamin E, beta-carotene, folate, and vitamin B12, and an improved riboflavin status when compared with participants assigned to placebo. Differences concerning vitamin C were statistically less relevant and those concerning vitamin A were at a borderline level. In the treated group the effect of supplementation on plasma levels of vitamins A, E, and C, and on the glutathione reductase activation coefficient was significantly higher in participants with lower nutritional status at baseline.

Clinical trials - more than an assessment of treatment effect: LXV Edward Jackson Memorial Lecture

PURPOSE

To review the development of clinical trials and demonstrate their value beyond the assessment of the treatment effect.

DESIGN

Retrospective literature review.

METHODS

Retrospective literature review.

RESULTS

There has been a rapid increase in the number of clinical trials in ophthalmology as assessed by the number of ophthalmic publications and the number of ongoing National Eye Institute-(NEI) sponsored clinical trials over the last four decades. The public health significance of the results of these NEI clinical trials goes beyond the demonstration of treatment effects and side effects. From these trials, we learn about the clinical course and risk factors of disease, allowing us to better determine who and when to treat. Furthermore, the collaboration of investigators, as they develop and carry out protocols, facilitates incorporation of new ideas into the practice of medicine.

CONCLUSIONS

The practice of medicine is increasingly dependent on the results of carefully designed clinical trials. The determination as to whether a new treatment is safe and effective is important, but the additional information we can obtain regarding natural history, risk factors, and patient satisfaction adds immeasurably to our ability to care for our patients.

Clinical detection of precataractous lens protein changes using dynamic light scattering

OBJECTIVE

To use dynamic light scattering to clinically assess early precataractous lens protein changes.

METHODS

We performed a cross-sectional study in 380 eyes of 235 patients aged 7 to 86 years with Age-Related Eye Disease Study clinical nuclear lens opacity grades 0 to 3.8. A dynamic light-scattering device was used to assess alpha-crystallin, a molecular chaperone protein shown to bind other damaged lens proteins, preventing their aggregation. The outcome measure was the alpha-crystallin index, a measure of unbound alpha-crystallin in each lens. The association of the alpha-crystallin index with increasing nuclear opacity and aging was determined.

RESULTS

There was a significant decrease in the alpha-crystallin index associated with increasing nuclear lens opacity grades (P < .001). There were significant losses of alpha-crystallin even in clinically clear lenses associated with aging (P < .001). The standard error of measurement was 3%.

CONCLUSIONS

Dynamic light scattering clinically detects alpha-crystallin protein loss even in clinically clear lenses. alpha-Crystallin index measurements may be useful in identifying patients at high risk for cataracts and as an outcome variable in clinical lens studies.

CLINICAL RELEVANCE

The alpha-crystallin index may be a useful measure of the protective alpha-crystallin molecular chaperone reserve present in a lens, analogous to creatinine clearance in estimating renal function reserve.

Risk of advanced age-related macular degeneration after cataract surgery in the Age-Related Eye Disease Study: AREDS report 25

PURPOSE

To assess the risk of advanced age-related macular degeneration (AMD) developing after cataract surgery.

DESIGN

Cohort study.

PARTICIPANTS

Four thousand five hundred seventy-seven participants (8050 eyes) from a multicenter, controlled, randomized clinical trial, the Age-Related Eye Disease Study (AREDS).

METHODS

Development of advanced AMD, either neovascular (NV) AMD or geographic atrophy (GA), was evaluated with annual fundus photographs, and history of cataract surgery was assessed every 6 months. Cox proportional hazard models with time-dependent covariates were conducted for NV AMD and GA separately.

MAIN OUTCOME MEASURES

Neovascular AMD, GA, and central GA (CGA; involving the center of the macula).

RESULTS

The Cox proportional hazards model of right eyes showed nonsignificant hazard ratios of 1.20 (95% confidence interval [CI], 0.82-1.75) for NV AMD, 0.80 (95% CI, 0.61-1.06) for GA, and 0.87 (95% CI, 0.64-1.18) for CGA. Similar results were obtained for left eyes: 1.07 (95% CI, 0.72-1.58) for NV AMD, 0.94 (95% CI, 0.71-1.25) for GA, and 0.86 (95% CI, 0.63-1.19) for CGA. For participants with advanced AMD in 1 eye (AREDS category 4), the hazard ratios for fellow eyes were 1.08 (95% CI, 0.65-1.72) for NV AMD and 0.98 (95% CI, 0.64-1.49) for CGA.

CONCLUSIONS

The AREDS results showed no clear effect of cataract surgery on the risk of progression to advanced AMD.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Age-related macular degeneration

Age-related macular degeneration is the leading cause of blindness in elderly populations of European descent. The most consistent risk factors associated with this ocular condition are increasing age and cigarette smoking. Genetic investigations have shown that complement factor H, a regulator of the alternative complement pathway, and LOC387715/HtrA1 are the most consistent genetic risk factors for age-related macular degeneration. Although the pathogenesis of this disease is unknown, oxidative stress might have an important role. Treatment with antioxidant vitamins and zinc can reduce the risk of developing advanced age-related macular degeneration by about a quarter in those at least at moderate risk. Intravitreal injections of ranibizumab, a monoclonal antibody that inhibits all forms of vascular endothelial growth factor, have been shown to stabilise loss of vision and, in some cases, improve vision in individuals with neovascular age-related macular degeneration. These findings, combined with assessments of possible environmental and genetic interactions and new approaches to modulate inflammatory pathways, will hopefully further expand our ability to understand and treat age-related macular degeneration.

The HtrA1 promoter polymorphism, smoking, and age-related macular degeneration in multiple case-control samples

OBJECTIVE

To assess the association and combined effect on the risk of age-related macular degeneration (AMD) by the HtrA1 and complement factor H (CFH) polymorphisms, smoking, and serum cholesterol.

DESIGN

Clinic-based and population-based case control study.

PARTICIPANTS

A total of 805 AMD cases and 921 controls from The Eye Clinic of National Eye Institute, Age-Related Eye Diseases Study, Blue Mountain Eye Study Cohort, and Minnesota Lions Eye Bank.

METHODS

DNA samples were genotyped for polymorphisms of rs11200638 in HtrA1 promoter and rs380390 in CFH. HtrA1 protein in ocular tissue was measured. Interactions of the HtrA1 risk allele with the CFH risk variant, smoking status, and cholesterol were assessed.

MAIN OUTCOME MEASURES

AMD was evaluated by retinal specialists, and AMD subtypes (geographic atrophy and neovascularization) were determined.

RESULTS

Strong associations of the HtrA1 risk allele (A) with AMD were present in all sample sets. A similar magnitude of association was observed for central geographic atrophy and neovascular AMD. The combination of the HtrA1 and CFH risk alleles increased AMD susceptibility, as did the combination of the HtrA1 risk allele with smoking. No combined effect of HtrA1 risk allele and cholesterol level was found. Enhanced expression of HtrA1 protein was detected in retina with AMD.

CONCLUSIONS

Findings from multiple samples support an AMD genetic variant harbored within HtrA1. The risk of advanced AMD increased when the presence of risk alleles from HtrA1 was combined with either CFH risk alleles or history of smoking.

The relationship of dietary omega-3 long-chain polyunsaturated fatty acid intake with incident age-related macular degeneration: AREDS report no. 23

OBJECTIVE

To examine the association of dietary omega-3 long-chain polyunsaturated fatty acid and fish intake with incident neovascular age-related macular degeneration (AMD) and central geographic atrophy (CGA).

METHODS

Multicenter clinic-based prospective cohort study from a clinical trial including Age-Related Eye Disease Study (AREDS) participants with bilateral drusen at enrollment. Main outcome measures were incident neovascular AMD and CGA, ascertained from annual stereoscopic color fundus photographs (median follow-up, 6.3 years). We estimated nutrient and food intake from a validated food frequency questionnaire (FFQ) at baseline, with intake of docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), combined EPA and DHA, and fish as primary exposures.

RESULTS

After controlling for known covariates, we observed a reduced likelihood of progression from bilateral drusen to CGA among people who reported the highest levels of EPA (odds ratio [OR], 0.44; 95% confidence interval [CI], 0.23-0.87) and EPA+DHA (OR, 0.45; 95% CI, 0.23-0.90) consumption. Levels of DHA were associated with CGA in age-, sex-, and calorie-adjusted models (OR, 0.51; 95% CI, 0.26-1.00); however, this statistical relationship did not persist in multivariable models.

CONCLUSIONS

Dietary lipid intake is a modifiable factor that may influence the likelihood of developing sight-threatening forms of AMD. Our findings suggest that dietary omega-3 long-chain polyunsaturated fatty acid intake is associated with a decreased risk of progression from bilateral drusen to CGA.

Optical coherence tomography measurements and analysis methods in optical coherence tomography studies of diabetic macular edema

OBJECTIVE

To evaluate optical coherence tomography (OCT) measurements and methods of analysis of OCT data in studies of diabetic macular edema (DME).

DESIGN

Associations of pairs of OCT variables and results of 3 analysis methods using data from 2 studies of DME.

PARTICIPANTS

Two hundred sixty-three subjects from a study of modified Early Treatment of Diabetic Retinopathy Study (mETDRS) versus modified macular grid (MMG) photocoagulation for DME and 96 subjects from a study of diurnal variation of DME.

METHODS

Correlations were calculated for pairs of OCT variables at baseline and for changes in the variables over time. Distribution of OCT measurement changes, predictive factors for OCT measurement changes, and treatment group outcomes were compared when 3 measures of change in macular thickness were analyzed: absolute change in retinal thickness, relative change in retinal thickness, and relative change in retinal thickening.

MAIN OUTCOME MEASURES

Concordance of results using different OCT variables and analysis methods.

RESULTS

Center point thickness correlated highly with central subfield mean thickness (CSMT) at baseline (0.98-0.99). The distributions of changes in CSMT were approximately normally distributed for absolute change in retinal thickness and relative change in retinal thickness, but not for relative change in retinal thickening. Macular thinning in the mETDRS group was significantly greater than in the MMG group when absolute change in retinal thickness was used, but not when relative change in thickness and relative change in thickening were used. Relative change in macular thickening provides unstable data in eyes with mild degrees of baseline thickening, unlike the situation with absolute or relative change in retinal thickness.

CONCLUSIONS

Central subfield mean thickness is the preferred OCT measurement for the central macula because of its higher reproducibility and correlation with other measurements of the central macula. Total macular volume may be preferred when the central macula is less important. Absolute change in retinal thickness is the preferred analysis method in studies involving eyes with mild macular thickening. Relative change in thickening may be preferable when retinal thickening is more severe.

Prevalence of refractive error in the United States, 1999-2004

OBJECTIVE

To describe the prevalence of refractive error in the United States.

METHODS

The 1999-2004 National Health and Nutrition Examination Survey (NHANES) used an autorefractor to obtain refractive error data on a nationally representative sample of the US noninstitutionalized, civilian population 12 years and older. Using data from the eye with a greater absolute spherical equivalent (SphEq) value, we defined clinically important refractive error as follows: hyperopia, SphEq value of 3.0 diopters (D) or greater; myopia, SphEq value of -1.0 D or less; and astigmatism, cylinder of 1.0 D or greater in either eye.

RESULTS

Of 14,213 participants 20 years or older who completed the NHANES, refractive error data were obtained for 12,010 (84.5%). The age-standardized prevalences of hyperopia, myopia, and astigmatism were 3.6% (95% confidence interval [CI], 3.2%-4.0%), 33.1% (95% CI, 31.5%-34.7%), and 36.2% (95% CI, 34.9%-37.5%), respectively. Myopia was more prevalent in women (39.9%) than in men (32.6%) (P < .001) among 20- to 39-year-old participants. Persons 60 years or older were less likely to have myopia and more likely to have hyperopia and/or astigmatism than younger persons. Myopia was more common in non-Hispanic whites (35.2%) than in non-Hispanic blacks (28.6%) or Mexican Americans (25.1%) (P < .001 for both).

CONCLUSION

Estimates based on the 1999-2004 NHANES vision examination data indicate that clinically important refractive error affects half of the US population 20 years or older.

A severity scale for diabetic macular edema developed from ETDRS data

PURPOSE

To develop a severity scale for diabetic macular edema (DME) and to assess relationships between severity and duration of DME and visual acuity (VA).

METHODS

From the Early Treatment Diabetic Retinopathy Study (ETDRS), mean baseline VA scores were tabulated for 7422 eyes cross-classified by (1) location of retinal thickening (RT) and its area within 1 disc diameter of the macular center, and (2) degree of RT at the center. Adjacent (row, column, and off-diagonal) cells with the greatest similarity in baseline VA (mean and SD) based on a Gaussian (normal) likelihood were merged. An initial eight-step scale was chosen using the Schwarz criterion (Bayesian information criterion; BIC) and was revised based on clinical judgment to nine steps. Relationships between baseline VA and other photographic and fluorescein angiographic characteristics were examined singly and in combination with the scale.

RESULTS

Modeling baseline VA as a function of the nine-step scale yielded an R(2) of 38.0%, compared with 38.4% using the full cross-classification of these variables. Addition of each of the other baseline characteristics changed the adjusted R(2) for the combination very little. Between scale levels 1A and 5B mean (SD) VA decreased from 86.8 (5.8) letters to 59.8 (13.6) letters. In a model of change in VA as a function of time spent at each DME severity level, VA loss increased progressively from 1 letter per year at level 2 to 17 letters per year at level 5B.

CONCLUSIONS

The scale facilitates documentation of the relationship of severity and duration of DME with VA.

Oral supplementation of lutein/zeaxanthin and omega-3 long chain polyunsaturated fatty acids in persons aged 60 years or older, with or without AMD

PURPOSE

Increased dietary intake of lutein/zeaxanthin and omega-long-chain polyunsaturated fatty acids (omega-3 LCPUFA) was found to be associated with reduced risk of advanced age-related macular degeneration (AMD). The purpose of the study was to examine the effect of oral supplementation of omega-3 LCPUFA on changes in serum levels of lutein/zeaxanthin during supplementation in persons 60 years of age and older, with or without AMD.

METHODS

Forty participants with AMD of various degrees of severity received lutein (10 mg) and zeaxanthin (2 mg) daily and were equally randomized to receive omega-3 LCPUFA (350 mg docosahexaenoic acid [DHA] and 650 mg eicosapentaenoic acid [EPA]) or placebo for 6 months. Serum levels of lutein, zeaxanthin, and omega-3 LCPUFAs and macular pigment optical densities were measured at baseline, 1 week, and 1, 3, 6, and 9 months.

RESULTS

By month 6, the median serum levels of lutein/zeaxanthin increased by two- to threefold compared with baseline. Increases in serum levels of lutein/zeaxanthin did not differ by omega-3 LCPUFA treatment (P > 0.5). After 1 month, in the omega-3 LCPUFA-treated group, the median levels of DHA and EPA increased and the placebo group had no changes. At month 6, participants with AMD had a lower increase in serum lutein concentration than did those without AMD (P < 0.05).

CONCLUSIONS

The addition of omega-3 LCPUFA to oral supplementation of lutein/zeaxanthin did not change the serum levels of lutein and zeaxanthin. A long-term large clinical trial is necessary to investigate the benefits and adverse effects of these factors for the treatment of AMD.

Cataract classification using serial examinations in the age-related eye disease study: age-related eye disease study report no. 24

PURPOSE

To describe use of serial lens examinations to assign cataract phenotype in the Age-Related Eye Disease Study (AREDS).

DESIGN

Cohort study.

METHODS

Lens photographs were graded annually using the AREDS system for classifying cataracts. Nuclear grades (0.9 to 6.1) were assigned using standard photographs. Percentage of pupillary involvement was used to assign cortical and posterior subcapsular grades. Cutpoints were established for the presence or absence of each type of opacity (absent<4.0 for nuclear, <10% for cortical, and <5% of central 5 mm for posterior subcapsular). An algorithm weighted for grades at the last three examinations was used to assign cataract phenotype. Separately, cataract phenotype was assigned as grade predicted at final visit by linear regression of serial grades. Results from the two approaches were compared and final person phenotypes were established. These person cataract phenotype assignments were compared with phenotype assignments based on the last serial grade alone.

RESULTS

Four thousand six hundred and twenty-eight AREDS participants aged 55 to 80 years at baseline had median follow-up of 10.6 years. Person phenotype assignments agreed for the two approaches in 4,557 (98.5%) participants after some algorithmic adjudication. Phenotypes were no cataract (n=1,418), nuclear (n=1,287), cortical (n=1,396), posterior subcapsular (n=541), cataract surgery and no specific opacity type (n=335), and questionable (n=426). Phenotype assignments based on serial grades and on last examination alone were in good agreement.

CONCLUSIONS

Serial lens photographs obtained over a 10-year period were used to provide a robust assignment of cataract phenotype. Well-characterized cataract phenotypes are of importance as genetic studies of the AREDS cohort are considered.

Retinal precursors and the development of geographic atrophy in age-related macular degeneration

PURPOSE

To determine specific retinal precursor lesions and sequence of events preceding the onset of geographic atrophy (GA) in eyes with age-related macular degeneration (AMD).

DESIGN

Retrospective review.

PARTICIPANTS

All participants in the Age-Related Eye Disease Study (AREDS) at 2 clinical centers (Devers Eye Institute, Portland, Oregon, and University of Wisconsin, Madison, Wisconsin) in whom GA initially appeared in at least one eye a minimum of 4 years after the baseline study visit.

METHODS

All stereoscopic fundus photographs taken before the appearance of GA in the involved (study) eye were reviewed. Fundus features at the site of future GA were graded and recorded. Three graders reviewed photographs, with independent grading and adjudication by mutual agreement. Features graded included drusen (classified by size and confluence), focal hyperpigmentation, hypopigmentation, and refractile deposits. The time between first appearance of these features and initial appearance of GA was recorded.

MAIN OUTCOME MEASURE

Appearance of GA.

RESULTS

Of all AREDS participants at the 2 sites, 95 eyes of 77 developed GA at least 4 years after entrance into the study. Average time from baseline to initial appearance of GA was 6.6 years (range, 4-11). Drusen were found in 100% of eyes at the site of later developing GA, drusen >125 mum in diameter in 96% of eyes, confluent drusen in 94%, hyperpigmentation in 96%, drusen > 250 mum in 83%, hypopigmentation in 82%, and refractile deposits in 23%. Time from lesion appearance to onset of GA varied by lesion type, ranging from 5.9 years for drusen confluence to 2.5 years for hypopigmentation or refractile deposits. Lesions generally followed a uniform sequence of appearance.

CONCLUSIONS

By focusing on the location of initial GA appearance and then retrospectively analyzing prior photographs, we were able to identify specific precursor lesions and the most common sequence of events leading to GA formation in eyes with AMD. The progression was usually characterized by large drusen formation and development of hyperpigmentation, followed by regression of drusen, appearance of hypopigmentation, and ultimately development of GA, sometimes preceded by the appearance of refractile deposits.

The relationship of dietary carotenoid and vitamin A, E, and C intake with age-related macular degeneration in a case-control study: AREDS Report No. 22

OBJECTIVE

To evaluate the relationship of dietary carotenoids, vitamin A, alpha-tocopherol, and vitamin C with prevalent age-related macular degeneration (AMD) in the Age-Related Eye Disease Study (AREDS).

METHODS

Demographic, lifestyle, and medical characteristics were ascertained on 4519 AREDS participants aged 60 to 80 years at enrollment. Stereoscopic color fundus photographs were used to categorize participants into 4 AMD severity groups and a control group (participants with < 15 small drusen). Nutrient intake was estimated from a self-administered semiquantitative food frequency questionnaire at enrollment. Intake values were energy adjusted and classified by quintiles. The relationship between diet and AMD status was assessed using logistic regression analyses.

RESULTS

Dietary lutein/zeaxanthin intake was inversely associated with neovascular AMD (odds ratio [OR], 0.65; 95% confidence interval [CI], 0.45-0.93), geographic atrophy (OR, 0.45; 95% CI, 0.24-0.86), and large or extensive intermediate drusen (OR, 0.73; 95% CI, 0.56-0.96), comparing the highest vs lowest quintiles of intake, after adjustment for total energy intake and nonnutrient-based covariates. Other nutrients were not independently related to AMD.

CONCLUSION

Higher dietary intake of lutein/zeaxanthin was independently associated with decreased likelihood of having neovascular AMD, geographic atrophy, and large or extensive intermediate drusen.

Visual Acuity as an Outcome Measure in Clinical Trials of Retinal Diseases

PURPOSE

Visual acuity (VA) is the primary outcome measure in many studies involving eye diseases. A standard statistical approach for comparing a continuous measurement such as a VA letter score between 2 treatment groups is to perform a t test comparing the means. However, frequently a binary variable is created from the continuous VA letter score based on whether or not there has been a worsening (or gain) of > or =15 letters (equivalent to > or =3 lines), and a chi square or similar statistical test is performed to compare the proportions of success (or failure) between groups. The purpose of this article is to contrast these 2 approaches.

METHODS

Clinical trial reports of retinal disorders were used to compare results using mean change in the VA letter score versus binary proportions created from the VA letter score. Additionally, analyses were performed using generated data to gain a perspective on the magnitude of differences that might be expected between the 2 methods.

RESULTS

Studies from the literature showed that differences of 6% to 15% in > or =15-letter worsening corresponded to mean differences in letter scores between groups of 3.0 to 7.0 (approximately 0.6 to 1.4 lines). Analyses using generated data demonstrated that a mean improvement in the VA letter score of 5 corresponded to a doubling of the proportion of eyes with > or =15-letter improvement and a 28% relative reduction in the proportion of eyes with > or =15-letter worsening.

CONCLUSIONS

How VA data should be analyzed in a clinical trial depends to large extent on the research question. The frequently used outcome of > or =15-letter change has several drawbacks, including loss of efficiency (need for a larger sample), misclassification of the outcome, and potential for a ceiling or floor effect. Therefore, for most clinical trials we believe that the primary outcome analysis should be a comparison of changes in the VA letter score, and created binary variables should be reported as secondary outcomes. This approach maximizes the information gained from the data and accommodates both improvement and worsening of acuity.

Early retinopathy progression in four randomized trials comparing insulin glargine and NPH [corrected] insulin

Early worsening of diabetic retinopathy, characterized by cotton wool spots, intraretinal microvascular abnormalities and/or macular edema, can occur following improvement of glycemic control. In four randomized 28- to 52-week clinical trials comparing insulin glargine and NPH insulin in regard to glycemic control and frequency of hypoglycemia, ophthalmologic examinations and fundus photographs were included to assess frequency of early worsening of retinopathy or other early adverse ocular effects. Retinopathy progression rates at 28 weeks were 7-12% by clinical examination and 3-8% by photographic grading; corresponding rates of clinically significant macular edema (CSME) were 1-8% and 1-4%, respectively. Optic disc swelling was not observed clinically or in photographs. Two of the 24 possible comparisons (four trials, three outcomes, two assessment methods), both of which were photographic assessments in type 2 diabetes, were in/near the nominally significant range and favored NPH insulin: 28-week rates of >or=3-step retinopathy progression (insulin glargine: 16/213, 7.5%; NPH insulin: 6/220, 2.7%; p=0.028) and 52-week CSME rates (26/233, 11.2% and 14/214, 6.5%, respectively; p=0.098). Because the between-treatment differences were small and inconsistent across trials and assessment methods, and because overall rates were consistent with the natural course of diabetic retinopathy, we conclude that it is unlikely that insulin glargine carries a higher risk of early worsening or other early adverse effect than NPH insulin. These trials tended to exclude a large early adverse effect, such as optic disc swelling, but cannot assess longer-term effects; a 5-year randomized trial of insulin glargine versus NPH insulin has been initiated. Data from this manuscript have been presented as posters and published in abstract form at the European Association for the Study of Diabetes 2001 ( DIABETOLOGIA 44(Suppl 1):I-IV(A287), 2001) and the Latin American Diabetes Association 2001 (11-15 November 2001, Punta del Este, Uruguay; Poster 180) congresses.