Differences in imaging biomarkers between patients with intermediate and advanced non-neovascular age-related macular degeneration (AMD) in the University of Colorado AMD registry.

PURPOSE: To quantify and compare the different prevalence rates of specific retinal imaging biomarkers in patients with intermediate AMD (iAMD) and advanced non-neovascular AMD (nnAMD). METHODS: Cross-sectional study of patients with iAMD and advanced nnAMD. Imaging studies were reviewed for qualitative imaging biomarkers. Choroidal thickness measurements were obtained subfoveally and in 1000 um and 2000 um intervals away from the fovea. The Chi-squared test and Fisher's exact test were used to compare rates of imaging biomarkers among the two cohorts. P-value of <0.05 was considered significant. RESULTS: 376 eyes of 197 patients with iAMD and 187 eyes of 97 patients with advanced nnAMD were recruited. There were significantly lower rates of the following imaging biomarkers in the iAMD compared with the advanced nnAMD cohorts: soft drusen (66.0% vs. 84.2%, p = 0.001), calcified drusen (4.3% vs. 40.0%, p < 0.0001), RPD (26.2% vs. 53.3%, p < 0.0001), ORT (0.5% vs. 46.9%, p < 0.0001), RP (1.1% vs. 46.3%, p < 0.0001), pigment migration (53.2% vs. 100%, p < 0.0001), and iRORA (17.9% vs. 80.2%, p < 0.0001). In the iAMD cohort, choroidal thickness was significantly greater at 188 µm (SD: 60) and 194 µm (SD: 69), compared to the advanced nnAMD with measurements of 153 µm (SD: 68), and 161 µm (SD: 76). This difference was statistically significant (p < 0.0001 and p = 0.0002). CONCLUSIONS: Our results highlight significant differences in imaging biomarkers between both cohorts. Key biomarkers, such as iRORA, RPD, pigment migration, and thinner choroidal thickness, were associated with advanced nnAMD. Identifying these biomarkers early may help target patients who could benefit from new treatments, potentially delaying vision loss.

Association Between Quantitative and Qualitative Imaging Biomarkers and Geographic Atrophy Growth Rate.

PURPOSE: Investigate associations between geographic atrophy (GA) growth rate and multimodal imaging biomarkers and patient demographics in patients with advanced non-neovascular age-related macular degeneration (nnAMD). DESIGN: Prospective cohort study. METHODS: One hundred twenty-one eyes of 66 patients with advanced nnAMD with GA enrolled in the University of Colorado AMD Registry from August 2014 to June 2021, with follow-up through June 2023. Multimodal images were reviewed by two graders for imaging biomarkers at enrollment. GA growth rate and square-root transformed (SQRT) GA growth rate were measured between enrollment and final visit. Associations between the outcome SQRT GA growth rate and imaging biomarkers, baseline GA lesions characteristics, and patient demographics were evaluated. RESULTS: Average GA growth rate was 1.430 mm2/year and SQRT GA growth rate was 0.268 mm/year over a mean of 3.7 years. SQRT GA growth rate was positively associated with patient age (P = .010) and female sex (0.035), and negatively associated with body mass index (0.041). After adjustment for these demographic factors, SQRT GA growth rate was positively associated with presence of non-exudative subretinal fluid (P < .001), non-exudative subretinal hyperreflective material (P = .037), and incomplete retinal pigment epithelium and outer retina atrophy (P = .022), and negatively associated with subfoveal choroidal thickness (P = .031) and presence of retinal pseudocysts (P = .030). Larger baseline GA size at enrollment was associated with faster GA growth rate (P = .002) but not SQRT GA growth rate. CONCLUSIONS: Select patient demographic factors and basic clinically-relevant imaging biomarkers were associated with GA growth rate. These biomarkers may guide patient selection when considering treating GA patients with novel therapeutics.

Are there sex-based disparities in cataract surgery?

AIM: To investigate sex-based differences in the occurrence of intra-operative and post-operative complications and associated visual outcomes following cataract surgery. METHODS: This was a retrospective study of patients who had phacoemulsification cataract surgery at the University of Colorado School of Medicine. Data collected included the patient's health history, ocular comorbidities, operative and post-operative complications, and the post-operative best corrected visual acuity (BCVA). The data were analyzed using univariate and multivariable logistic regression with generalized estimating equations to account for the correlation of some patients having two eyes included in the study. RESULTS: A total of 11 977 eyes from 7253 patients were included in the study. Ocular comorbidities differed by sex, with males having significantly higher percentages of traumatic cataracts (males 0.7% vs females 0.1%), prior ocular surgery (6.7% vs 5.5%), and mature cataracts (2.8% vs 1.9%). Conversely, females had significantly higher rates of pseudoexfoliation (2.0% vs 3.2%). In unadjusted analysis, males had higher rates of posterior capsular rupture (0.8% vs 0.4%) and vitreous loss (1.0% vs 0.6%), but this difference was not significant after adjustment for confounders. Males had a significantly increased risk of post-operative retinal detachment, but in multivariable analysis this was no longer significant. Males were significantly less likely to undergo post-operative neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy for posterior capsule opacification (OR=0.8, 95%CI=0.7-0.9, P=0.0005). The BCVA was slightly worse for males pre-operatively; but post-operatively, both sexes exhibited similar visual acuity of Snellen equivalent 20/25. CONCLUSION: The study finds that in a cohort of patients presenting for cataract surgery, sex differences exist in pre-operative comorbidities and surgical characteristics that contribute to higher rates of some complications for males. However, observed surgical complication rates exhibit almost no difference by sex after adjusting for pre-operative differences and post-operative BCVA is similar between sexes.

An Evaluation of the Repeatability of Visual Function Following Surgical Repair of Macula-Off Rhegmatogenous Retinal Detachment.

Purpose: To evaluate the reliability and reproducibility of visual function assessments for patients with macula-off rhegmatogenous retinal detachment (RRD). Methods: This prospective study included patients with unilateral macula-off RRD of <10-day duration successfully treated with a single, uncomplicated surgery at least 1 year following repair. Visual function assessments were performed at time of enrollment and 1 month later. Testing included Early Treatment Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (BCVA), low-luminance visual acuity (LLVA), low-contrast visual acuity (VA) 2.5% and 5%, contrast sensitivity assessment with Mars and Gabor patches, reading speed (acuity, speed, and critical print size), color vision testing (protan, deutan, and tritan), and microperimetry. Spectral-domain ocular coherence tomography (SD-OCT) was performed. Paired t-statistics were used to compare values between visits and between the study and fellow eyes. Results: Fourteen patients (9 male, 5 female) with a mean age of 69 years at time of surgery were evaluated. Correlation coefficients across the two visits were highest for ETDRS BCVA (0.97), tritan color vision testing (0.96), and low-contrast VA 5% (0.96), while the average t-statistic was largest for low-luminance deficit (4.2), ETDRS BCVA (4.1), and reading speed critical print size (3.7). ETDRS BCVA did not correlate with SD-OCT findings. Conclusions: ETDRS BCVA can be considered a highly reliable and reproducible outcome measure. LLVA, protan color discrimination, contrast sensitivity, and reading speed may be useful secondary outcome measures. Translational Relevance: This study provides guidance on the selection of visual function outcome measures for clinical trials of patients with macula-off RRD.

Risk Factors and Outcomes of Delayed Presentation of Diabetic Retinopathy Patients to a County Hospital.

Purpose: To identify risk factors and evaluate outcomes of patients with delayed presentation and advanced diabetic retinopathy in our safety-net county hospital population. Methods: A retrospective study was performed on 562 patients who presented with a new diagnosis of diabetic retinopathy (DR). Delayed presentation was defined as moderate or severe nonproliferative diabetic retinopathy (NPDR) or proliferative diabetic retinopathy (PDR) at the initial visit. Comparisons between patient groups were performed with chi-square or Fisher's exact test for categorical variables and multinomial logistic regression for multivariable analysis. Linear and logistic regression modeling with general estimating equations to account for patients having two eyes was used to compare eye-level outcomes. Results: Lack of a primary care provider (PCP) was highest in patients who presented initially with PDR (28.8%), compared to 14.3% in moderate/severe NPDR, 12.4% in mild NPDR, and 7.6% in no DR groups (P < 0.001). Only 69.4% of patients with a PCP had an ophthalmology screening referral. Highest lack of referral (47.2%) was seen in the PDR group (P = 0.002). Patients with PDR were more likely to be uninsured (19.2%) compared to no and mild DR groups, with rates of 7.6% and 9.0%, respectively (P = 0.001). The PDR group had worse initial and final visual acuities (P < 0.001). Conclusions: Several risk factors were noted for delayed DR presentation, including lack of PCP, lack of screening referral, and uninsured/underinsured status. Patients with advanced DR at presentation had worse final visual outcomes despite aggressive treatment. Translational Relevance: Screening programs targeting populations with identified risk factors are essential for improving outcomes.

Interleukin-4 Plasma Levels Stratified by Sex in Intermediate Age-Related Macular Degeneration and Geographic Atrophy.

Purpose: Chronic local inflammation underlies the pathogenesis of age-related macular degeneration (AMD) causing damage to the neurosensory retina. However, there is minimal research on systemic cell-mediated inflammation in AMD. Interleukin-4 (IL-4) is an immunoregulatory cytokine with an important role in modulating inflammation in chronic immune mediated disease. The purpose of this study was to: (1) investigate the role of systemic IL-4 in patients with intermediate AMD (iAMD) and in geographic atrophy (GA), an advanced form of AMD, compared to controls without AMD, and (2) determine if IL-4 levels are moderated by sex. Methods: We examined plasma levels of IL-4 in patients with iAMD, GA, and controls without AMD included in the University of Colorado AMD registry (August 2014 to June 2021). Cases and controls were defined by multimodal imaging. IL-4 was measured by multiplex immunoassay. Data were analyzed using a nonparametric rank based linear regression model fit to IL-4. Results: There were 199 patients with iAMD, 97 patients with GA, and 139 controls, with a percentage of female patients 61%, 55%, and 66%, respectively. We demonstrated significantly higher median IL-4 levels in GA (35.3; interquartile range [IQR] = 22.8-50.5) compared to iAMD (6.1; IQR = 2.2-11.3, P < 0.01) and controls (10.7; IQR = 5.0-16.8, P < 0.01). There were no significant differences in levels of IL-4 for cases and controls when stratified by sex. Conclusions: These findings demonstrate a systemic immunological difference between iAMD and GA, indicating IL-4 may be a systemic biomarker for GA development. Translational Relevance: The plasma biomarker IL-4 is significantly elevated in patients with GA.

Visual Functioning and Mortality of Age-Related Macular Degeneration Patients in a Colorado Cohort.

OBJECTIVE: To investigate the relationship between visual functioning as measured by the National Eye Institute 25-Item Visual Function Questionnaire (VFQ-25) and mortality in patients with various stages of age-related macular degeneration (AMD). DESIGN: Observational cohort study. PARTICIPANTS: Patients with AMD enrolled in the University of Colorado AMD Registry between July 9, 2014 and December 31, 2021 were included. METHODS: Age-related macular degeneration cases were classified into early AMD, intermediate AMD, geographic atrophy, neovascular AMD, or both advanced types of AMD (neovasuclar and geographic atrophy both present) using multimodal imaging and the Beckman and Classification of Atrophy Meetings criteria. Visual Function Questionnaire -25 composite and subscale scores at the time of study enrollment were calculated. Cox proportional hazards modeling was used to assess time to event for mortality utilizing univariate and multivariable models, which adjusted for all variables significantly associated with mortality. The measures of association were hazard ratios (HRs) and 95% confidence intervals (CIs). MAIN OUTCOME MEASURES: All-cause mortality statistics were obtained through a collaborative agreement with the Colorado Department of Public Health and Environment. Death rates through October 19, 2022 were compared by demographics and potential confounders. RESULTS: Analysis was completed on a cohort of 876 patients, of which 180 (20.6%) died during the follow-up period. Average follow-up time for this cohort was 52.5 (standard deviation: 26.6) months. In univariate analysis, composite VFQ-25 score and all subscale scores aside from ocular pain were significantly associated with time to mortality. Additionally, age, AMD category, marital status, history of smoking, and multiple chronic comorbid conditions were significantly associated with time to mortality. In multivariable analysis, for each 10-point increase in a patient's VFQ-25 scores for general health and driving, the risk of death decreased with HR of 0.85 (95% CI: 0.80, 0.91; P < 0.0001) and 0.92 (95% CI: 0.87, 0.97; P = 0.005), respectively. Composite and other subscale scores were not significantly associated with mortality after adjusting for confounding variables. CONCLUSIONS: This cohort of AMD patients had a 20% rate of death in the 52.5-month average follow-up time. Better general health and ability to drive, as measured by the VFQ-25, were each separately associated with significantly lower risk of death among individuals with AMD. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

RANTES (CCL5) in Patients With Geographic Atrophy Age-Related Macular Degeneration.

Purpose: A previous study from our research group showed significantly lower levels of RANTES (Regulated upon Activation, Normal T Cell Expressed and Secreted) in patients with intermediate age-related macular degeneration (AMD) compared to control patients with no AMD. The primary aim of this study was to assess levels of RANTES in a cohort of patients with a more advanced form of the disease, geographic atrophy (GA), in comparison with controls. Methods: The study was conducted on a cohort of patients with GA recruited into a Colorado AMD registry. Cases and controls were defined with multimodal imaging. Plasma levels of the chemokine RANTES were measured using a multiplex assay. A nonparametric (rank-based) regression model was fit to RANTES with a sex by AMD category interaction. Results: The plasma levels of RANTES were significantly higher in the control group in comparison to the GA AMD group (median [interquartile range]): 10,204 [5799-19,554] pg/mL vs. 5435 [3420-9177] pg/mL, respectively, P < 0.01). When moderated by sex, there was no statistical difference between the male and female GA AMD or the male and female controls. Conclusions: We found lower level of RANTES in patients with GA AMD compared with controls. This finding is consistent with the findings from our previous intermediate AMD study. However, in contrast to the results of our previous research, when moderated by sex there was no statistical difference between male and female GA patients. Translational Relevance: The biomarker RANTES is significantly lower in GA AMD patients compared to controls.

Low Vision Referral Patterns in Intermediate Age-Related Macular Degeneration.

PURPOSE: Sparse data exist regarding low vision (LV) services referral patterns. We retrospectively examined our institution's intermediate age-related macular degeneration (iAMD) patients to determine factors influencing referral. METHODS: We compared visual acuity (VA) and Visual Function Questionnaire (VFQ-25) composite and subscale scores for referred and non-referred iAMD patients. VA was collected at time of referral or most recent visit, and VFQ-25 was taken upon enrollment into the registry. RESULTS: Thirty-six (15.5%) of the 232 iAMD patients were referred to LV. Referred patients were more likely to have older age, worse VA in both eyes, and lower VFQ-25 scores. Univariate analysis of VFQ-25 subscales demonstrated worse scores in general vision, near, distance, mental health, role limitations, dependency, and driving. Multivariable analysis revealed lower scores in general health, general vision, and driving. Forty-eight percent of non-referred patients had VA or VFQ-25 composite scores at least as poor as the median for referred patients. Two-thirds of patients who were not referred had no discernable obstacle to referral. CONCLUSIONS: Our institution refers patients with worse objective and functioning vision, but more patients may benefit from referral. Future studies should identify metrics to prompt referral and evaluate this approach.

Mental health and visual acuity in patients with age-related macular degeneration.

BACKGROUND: Visual acuity (VA) loss has been associated with depression in patients with age-related macular degeneration (AMD). However, previous studies did not incorporate subgroups of AMD when correlating VA and mental health. The goal of this study was to describe the relationship between VA and mental health questions in patients with different classifications of AMD, and to identify associations of mental health subscale scores. METHODS: AMD patients classified by multi-modal imaging were recruited into an AMD registry. Habitual VA was obtained by ophthalmic technicians using the Snellen VA at distance. At enrollment, patients completed the NEI-VFQ-25, which includes 25 questions regarding the patient's visual functionality. Median with interquartile-range (IQR) scores on the mental health subscale of the VFQ were calculated by AMD classification and VA groups. Univariate and multivariable general linear models were used to estimate associations between mental health scores and variables of interest. RESULTS: Eight hundred seventy-five patients were included in the study. Patients with bilateral geographic atrophy (GA) or bilateral GA and neovascular (NV) AMD scored lowest on the mental health subscales with a median (IQR) of 58.2 (38-88) and 59.3 (38-88). When stratified by VA, patients with a habitual VA of 20/200 or worse scored the lowest on mental health subscales scores: median of 43.8 (IQR: 31-62). Patients with a VA of 20/20 scored the highest: 87.5 (IQR: 81-94). Habitual VA of the better- and worse-seeing eye and AMD classification were significantly associated with mental health subscale scores (all p < 0.0001 in both the univariate and multivariable analysis, except the VA of the worse-seeing eye in multivariable model p = 0.027). Patients enrolled during the COVID pandemic had mental health scores that were 2.7 points lower than prior to the pandemic, but this difference was not significant in univariate (p = 0.300) or multivariable analysis (p = 0.202). CONCLUSION: There is a significant association between mental health questionnaire scores and AMD classification, as well as VA in both the better and worse-seeing eyes in patients with AMD. It is important for clinicians to recognize feelings of worry/ frustration in these patients, so they can be appropriately referred, screened, and treated for mental health problems.

Gender Differences in Visual Functioning Questionnaire Scores among Patients with Age-Related Macular Degeneration.

PURPOSE: To examine gender differences in visual functioning using the National Eye Institute Visual Functioning Questionnaire-25 (VFQ-25) in a Colorado cohort of patients with age-related macular degeneration (AMD). METHODS: A retrospective cohort study was conducted using a registry of AMD patients who attended the Sue Anschutz-Rodgers Eye Center (2014 to 2019). Demographic, clinical, and image data were collected, and AMD was categorized as Early/Intermediate AMD, or unilateral/bilateral neovascular (NV) AMD, geographic atrophy (GA), or Both Advanced using the Beckman Classification. Each patient completed the VFQ-25, which evaluates visual functioning, generating a composite score and subscale scores for vision-specific activities. Univariate and multivariable general linear models were used to estimate the associations between gender and VFQ-25 scores with parameter estimates (PE) and standard errors (SE). RESULTS: Among 739 patients with AMD, 294 (39.8%), 115 (15.6%), 168 (22.7%), and 162 (21.9%) were diagnosed with Early/Intermediate AMD, GA, NV AMD, and Both Advanced, respectively. Adjusted for AMD classification, age and habitual visual acuity in the better-seeing and worse-seeing eyes, female gender was not significantly associated with lower composite VFQ-25 scores (PE (SE): -1.2 (0.9), p = .193), and was significantly associated with reportedly worse ocular pain and driving subscale scores (PE (SE): -4.6 (1.0), p < .0001 and -9.1 (2.1), p < .0001, respectively). CONCLUSION: Gender plays a role in reported driving activities and ocular pain among patients with AMD. This may need to be accounted for in future research related to the use of VFQ-25 for AMD.

Sex and Age-Related Differences in Complement Factors Among Patients With Intermediate Age-Related Macular Degeneration.

Purpose: Age-related macular degeneration (AMD) is an acquired degenerative disease of the retina classified into early, intermediate, and advanced AMD. A key factor in the pathogenesis of AMD is the complement system. The interaction of age and sex with the complement system may affect the risk of developing AMD. The purpose of this study was to determine if there were sex-specific differences in levels of complement factors among patients with the intermediate phenotype of AMD (iAMD) and explore the correlation between age and complement proteins. Methods: We studied complement factors in patients with iAMD and controls without AMD. Nonparametric, rank-based linear regressions including a sex by AMD interaction were used to compare levels for each analyte. Correlations between age and complement proteins were evaluated using the Spearman rank correlation coefficient. Results: We found significantly higher levels of factor B and factor I in females compared with males with iAMD, whereas no differences were seen in complement levels in male and female controls. The ratios of Ba/factor B, C3a/C3, C4b/C4, and C5a/C5 were not different in males and females with iAMD. Conclusions: We demonstrate disparities in a subset of systemic complement factors between females and males with iAMD, but apparent complement turnover as measured by ratios of activation fragments to intact molecules was not different between these groups. The results suggest that complement system levels, including complement regulator factor I, exhibits sex-related differences in patients with iAMD and highlights that stratification by sex might be helpful in the interpretation of clinical trials of anticomplement therapy.

Correlation of Complement Activation in Aqueous and Vitreous in Patients With Proliferative Diabetic Retinopathy.

Purpose: A growing body of evidence suggests complement dysregulation is present in the vitreous of patients with diabetic eye disease. Further translational study could be simplified if aqueous-as opposed to vitreous-were used to sample the intraocular complement environment. Here, we analyze aqueous samples and assess whether a correlation exists between aqueous and vitreous complement levels. Methods: We collected aqueous, vitreous, and plasma samples from patients with and without proliferative diabetic retinopathy (PDR) undergoing vitrectomy. We assessed correlation between complement levels in aqueous and vitreous samples after using a normalizing ratio to correct for vascular leakage. Spearman correlation coefficients were used to assess the correlation between complement levels in the aqueous and vitreous. Results: Aqueous samples were obtained from 17 cases with PDR and 28 controls. In all patients, aqueous Ba, C3a, and albumin levels were strongly correlated with vitreous levels (Spearman correlation coefficient of 0.8 for Ba and C3a and 0.7 for albumin; all P values < 0.0001). In PDR eyes only, aqueous and vitreous C3a levels were significantly correlated (Spearman correlation coefficient 0.7; P = 0.002), whereas in control eyes, both Ba and C3a (Spearman correlation coefficients of 0.7; P < 0.0001) were significantly correlated. Conclusions: A strong correlation exists between aqueous and vitreous complement levels in diabetic eye disease. Translational Relevance: The results establish that accurate sampling of the intraocular complement can be done by analyzing aqueous specimens, allowing for the rapid and safe measurement of experimental complement targets and treatment response.

An Exploratory Study to Investigate the Utility of Clinical Screening for Neurodegenerative Disease in Age-Related Eye Disease Research.

BACKGROUND: Unrecognized neurodegenerative diseases (NDD) in age-related eye disease research studies have the potential to confound vision-specific quality of life and retinal optical coherence tomography (OCT) outcome measures. The aim of this exploratory study was to investigate relationships between NDD screening tools and visual outcome measures in a small cohort of controls from the Colorado Age-Related Macular Degeneration Registry (CO-AMD), to consider the utility of future studies. METHODS: Twenty-nine controls from the CO-AMD were screened using the Montreal Cognitive Assessment (MoCA), a Colorado Parkinsonian Checklist, and the Lewy Body Composite Risk Score. Univariate and multivariable linear regression modeling was used to assess associations between screening tools and the National Eye Institute Visual Function Questionnaire-25 (VFQ-25) and macular OCT outcome measures, and t tests were used to evaluate outcome measure differences between those with normal vs abnormal MoCA scores. RESULTS: One patient withdrew. The average age was 72.8 years, and 68% were female patients. Ten participants (36%) had abnormal MoCA scores, and their VFQ-25 scores were only 1 point less and not statistically different than those with normal MoCA scores. Macular OCT volumes and thicknesses for retinal nerve fiber layer (RNFL) and retinal ganglion cell layer were consistently and moderately lower for those with abnormal MoCA scores, and a positive association between MoCA and macular RNFL volume was observed, although differences and regression were not significant. Parkinson screening tests were abnormal for only 4 participants and were not associated with OCT or VFQ-25 measures by regression modeling. CONCLUSIONS: Given the degree and direction of observed differences, further investigation is warranted regarding the relationship between cognitive screening tools and macular OCT measures in age-related eye disease research, but future investigations regarding the relationship between NDD screening tools and VFQ-25 seem unwarranted.

Gender as an effect modifier in the relationship between hypertension and reticular pseudodrusen in patients with early or intermediate age-related macular degeneration.

AIM: To determine whether the prevalence of treated hypertension is higher among males or females with early/intermediate (e/i) age-related macular degeneration (AMD) with and without bilateral reticular pseudodrusen (RPD). METHODS: Retrospective review of the records of patients with e/iAMD who were recruited into the University of Colorado AMD registry between July 2014 and November 2019. Images were classified using the Beckman Initiative criteria and presence/absence of RPD. Patients were categorized into three groups: 1) e/iAMD with RPD; 2) e/iAMD without RPD; 3) control patients who did not have AMD. Multinomial logistic regression analysis was used for adjusted analysis with odds ratios (OR) and confidence intervals (CI). RESULTS: There were 260 patients with e/iAMD of which 101 had bilateral RPD and 159 had no RPD, and 221 controls. Overall, 62% of patients were female and the three groups did not differ by gender. When stratified by gender, the female e/iAMD/RPD group had a higher prevalence of hypertension, 64.1% vs 45.2% for controls, OR=2.2 (95%CI: 1.2-4.0). The frequency of hypertension in the e/iAMD/no RPD group was 54.1% and did not significantly differ from the control group. Among males, prevalence rates of treated hypertension did not differ. There is a significant interaction of hypertension and gender for the e/iAMD/RPD group such that women with e/iAMD who had RPD were significantly more likely to have hypertension (P=0.042). This relationship was not significant in the e/iAMD/no RPD group (P=0.269). CONCLUSION: Among females treated hypertension is significantly higher among e/iAMD/RPD patients, whereas for males there is no significant association.

Sex Differences in RANTES (CCL5) in Patients With Intermediate Age-Related Macular Degeneration (AMD) and Controls With no AMD.

PURPOSE: To determine if there are sex differences in levels of regulated upon activation, normal T cell expressed and secreted (RANTES) in patients with intermediate age-related macular degeneration (iAMD) and in controls with no AMD. METHODS: Patients with iAMD and controls defined by multi-modal imaging were recruited into a Colorado AMD registry. Plasma levels of the chemokine RANTES were measured using a multiplex assay. A nonparametric (rank-based) regression model was fit to RANTES with a sex by AMD category interaction. RESULTS: The plasma level of RANTES was significantly higher in the control group in comparison with the iAMD group. When moderated by sex, RANTES was significantly lower (P = 0.005) in males (median, 4525.6 pg/mL; interquartile range, 2589-7861 pg/mL) compared with females (median, 6686 pg/mL; interquartile range, 3485-12488 pg/mL) within the iAMD cohort. No significant difference was found in levels of RANTES between males and females in the control group. CONCLUSIONS: We found that levels of RANTES were moderated by sex in cases with iAMD with lower levels in males compared with females. The findings illustrate the importance of including sex as a biological variable in AMD research. There is a need for further studies of RANTES, stratified by sex, in the advanced phenotypes of AMD. TRANSLATIONAL RELEVANCE: The biomarker RANTES identified in the plasma of patients with iAMD reflects systemic alterations when stratified by sex.

Association of Systemic Inflammatory Factors with Progression to Advanced Age-related Macular Degeneration.

PURPOSE: Age-related macular degeneration (AMD) is a leading cause of vision loss in the elderly. The role of systemic inflammation in AMD remains unclear specifically in patients with intermediate AMD (iAMD). We sought to determine whether systemic inflammation was associated with future iAMD progression. METHODS: Combinations of 27 circulating inflammatory markers including complement factors, cytokines, chemokines, and high-sensitivity C-reactive protein (hsCRP) were evaluated in iAMD patients recruited into a Colorado AMD registry. Systemic inflammatory markers were combined using principal component analysis. Risk factors for AMD progression were evaluated using Cox regression models. RESULTS: This study included 99 subjects with iAMD, 21 of which progressed to advanced AMD. Two principal components (PCs) were identified that contributed to the risk of progression to advanced AMD, after adjusting for age and bilateral reticular pseudodrusen. The strongest associated PC was explained largely by the pro-inflammatory cytokine TNFα and the anti-inflammatory IL1ra antagonist of IL1. The additional PC was largely explained by IL6, IL8, C3 and factor D in the positive direction and CRP, MCP1, factor B and factor I in the negative direction. CONCLUSION: When evaluated through multivariate analyses, combinations of biomarkers distinguished patients who did and did not progress to future advanced AMD. Increased risk could result from different combinations of analyte levels indicating a complex relationship rather than a simple increase in a few markers. This suggests that studying systemic inflammation in iAMD can provide insights into early pathologic events and potentially identify patients at highest risk for the development of severe AMD.

Plasma C-C Chemokine Concentrations in Intermediate Age-Related Macular Degeneration.

Purpose: To determine the relationship between plasma concentrations of the C-C chemokines CCL2, CCL3, CCL4, and CCL5 and intermediate age-related macular degeneration (iAMD) patients compared with control inidividuals to further define the inflammatory pathways associated with age-related macular degeneration. Methods: The concentrations of CCL2, CCL3, CCL4, and CCL5 were measured using multiplex assays in plasma collected from 210 patients with iAMD and 102 control individuals with no macular degeneration as defined by multi-modal imaging. Non-inflammatory data included in the analysis were: age, sex, family history of AMD, history of smoking, body mass index, presence of reticular pseudo-drusen and cardiovascular disease. Median concentrations as well as a cutoff value for each chemokine were compared between the two groups. Results: The median concentrations of CCL2 and CCL4 did not differ between control and iAMD groups, however, CCL2 was elevated in iAMD when a cutoff comparison was used (p < 0.05). Median CCL3 and CCL5 concentrations were significantly decreased in the macular degeneration group compared with controls (p < 0.001) as well as when a cutoff value comparison was used. CCL3 and CCL5 were negatively correlated in cases and positively correlated in controls. Conclusions: Plasma CCL3 and CCL5 concentrations were significantly decreased and CCL2 concentrations were increased in patients with iAMD compared with controls, suggesting a role for C-C chemokines in the systemic inflammatory processes associated with disease development.

Increased Systemic C-Reactive Protein Is Associated With Choroidal Thinning in Intermediate Age-Related Macular Degeneration.

Purpose: C-reactive protein (CRP) and decreased choroidal thickness (CT) are risk factors for progression to advanced age-related macular degeneration (AMD). We examined the association between systemic levels of CRP and CT in patients with intermediate AMD (iAMD). Methods: Patients with iAMD in the Colorado AMD Registry were included. Baseline serum samples and multimodal imaging including spectral domain-optical coherence tomography (SD-OCT), fundus photography, and autofluorescence were obtained. Medical and social histories were surveyed. CT was obtained by manual segmentation of OCT images. High-sensitivity CRP levels were quantified in serum samples. Univariate and multivariable linear regression models accounting for the intrasubject correlation of two eyes were fit using log-transformed CT as the outcome. Results: The study included 213 eyes from 107 patients with a mean age of 76.8 years (SD, 6.8). Median CT was 200.5 µm (range, 86.5-447.0). Median CRP was 1.43 mg/L (range, 0.13-17.10). Higher CRP was associated with decreased CT in the univariate model (P = 0.01). Older age and presence of reticular pseudodrusen (RPD) were associated with decreased CT (P < 0.01), whereas gender, body mass index, and smoking were not associated with CT. Higher CRP remained significantly associated with decreased CT after adjustment for age and RPD (P = 0.01). Conclusions: Increased CRP may damage the choroid, leading to choroidal thinning and increased risk of progression to advanced AMD. Alternatively, CRP may be a marker for inflammatory events that mediate ocular disease. The results of this study further strengthen the association between inflammation and AMD. Translational Relevance: Increased CRP is associated with choroidal thinning, a clinical risk factor for AMD.