Complement Factor H Genotype Research Articles

Complement factor H Y402H polymorphism results in diminishing CD4+ T cells and increasing C-reactive protein in plasma

Age-related macular degeneration (AMD) is a common cause of visual loss among the elderly. Genetic variants in the gene encoding complement factor H (CFH) have been identified as an AMD susceptibility gene, however, the mechanistic link is debated. Here, we investigated the link between the CFH Y402H genotype and low-grade inflammation. We recruited 153 healthy individuals, 84 participants with dry stages of AMD, and 148 participants with neovascular AMD. All participants were subjected to detailed retinal examination, and interview regarding comorbidities and lifestyle. Blood samples were analyzed for level of C-Reactive Protein (CRP), white blood cell differential count, and stained with fluorescent antibodies to differentiate CD4+ and CD8+ T cells. CFH Y402H genotyping was performed using an allele-specific polymerase chain reaction genotyping assay. Splenocytes from young and aged wild type and Cfh null mutant C57BL/6J mice were examined for CD4+ and CD8+ T cells. Healthy individuals with the CFH Y402H at-risk polymorphism HH had higher levels of CRP and lower proportions of CD4+ T cells compared to persons with the YH or YY polymorphism (P = 0.037, Chi-square). Healthy individuals with the HH polymorphism displayed lower proportions of CD4+ T cells with ageing (P < 0.01, one-way ANOVA), whereas both young and aged Cfh null mutant mice displayed lower proportions of CD4+ T cells (P < 0.001 and P < 0.05; unpaired t test). Participants with dry AMD and the HH polymorphism had similarly lower proportions of CD4+ T cells (P = 0.024, one-way ANOVA), but no difference in CRP-levels. In the neovascular stage of AMD, there was no difference in proportion of CD4+ cells or CRP levels according to genotype. The risk-associated CFH genotype is associated with an age-related decrease in proportion of CD4+ T cells and increased levels of CRP in healthy individuals. This indicates that decreased complement regulation results in extensive changes in innate and adaptive immune compartments that precede development of AMD.

Proteomic genotyping of SNP of Complement Factor H (CFH) Y402H and I62V using multiple reaction monitoring (MRM) assays

The single nucleotide polymorphisms (SNPs) of complement factor H (CFH) gene are well-known genetic risk factors for age-related macular degeneration (AMD). To identify whether the measurement of plasma protein concentrations of CFH variants using the multiple reaction monitoring (MRM) assay can determine the genotypes of CFH SNP rs1061170 and rs800292, 120 patients with AMD and 26 controls were included in this study. The number of cases were TT:TC:CC = 121:24:1 in CFH SNP Y402H and GG:AG:AA = 72:57:17 in CFH SNP I62V. Plasma concentrations of tryptic peptides were measured using the MRM assay, and tyrosine/histidine (Y/H) and valine/isoleucine (V/I) CFH variant protein ratios were obtained. To discriminate the genotypes by the plasma protein ratios, cut-off values were set for Y/H ratios (TT: > 4.428; TC: 1.00–4.428; CC: < 1.00) and V/I ratios (GG: > 1.09; AG: 0.0089–1.08; AA: < 0.0089). Correlation analysis revealed that the plasma CFH variant protein ratios and genotypes of CFH were exactly matched (100%) without overlap in the total patients and controls. The measurement of plasma protein CFH variants using the MRM assay can accurately identify the genotypes of CFH SNPs of Y402H and I62V.

Inflammasome Activation in Retinal Pigment Epithelium from Human Donors with Age-Related Macular Degeneration.

Age-related macular degeneration (AMD), the leading cause of blindness in the elderly, is characterized by the death of retinal pigment epithelium (RPE) and photoreceptors. One of the risk factors associated with developing AMD is the single nucleotide polymorphism (SNP) found within the gene encoding complement factor H (CFH). Part of the innate immune system, CFH inhibits alternative complement pathway activation. Multi-protein complexes called inflammasomes also play a role in the innate immune response. Previous studies reported that inflammasome activation may contribute to AMD pathology. In this study, we used primary human adult RPE cell cultures from multiple donors, with and without AMD, that were genotyped for the Y402H CFH risk allele. We found complement and inflammasome-related genes and proteins at basal levels in RPE tissue and cell cultures. Additionally, treatment with rotenone, bafilomycin A, and ATP led to inflammasome activation. Overall, the response to priming and activation was similar, irrespective of disease state or CFH genotype. While these data show that the inflammasome is present and active in RPE, our results suggest that inflammasome activation may not contribute to early AMD pathology.

Association of Complement Factor H (CFH) Y402H Gene Polymorphism and Serum CFH with Risk of Age Related Macular Degeneration in Egyptian Patients

AbstractBackground: Age related Macular Degeneration (AMD) is stated as the most common cause of irreversible blindness among aging populations. It has been reported that both Complement Factor H (CFH) Y402H polymorphism and serum CFH concentration are linked to AMD.Aim of Study: To determine whether Y402H polymorphism and serum level of CFH are associated with AMD in the Egyptian population.Material and Methods: Eighty subjects were recruited; 40 AMD patients and 40 matched healthy individuals as control. Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) was performed for the analysis of CFH Y402H gene polymorphism. Serum CFH concentration was measured using Enzyme Linked-Imm-unosorbent Assay (ELISA).Results: Susceptibility to AMD in Egyptian population was not associated with CFH Y402H polymorphism and the presence of C allele is not considered risky; Odds Ratio (OR): 0.545, 95% CI (0.291-1.022). No significant association between CFH genotypes and AMD. Serum CFH concentration showed no statistically significant difference between cases & controls (p=0.706). In controls, there was a statistically significant decrease in serum CFH level in CC genotype compared to both CT genotype (p=0.038) and TT genotype (p=0.007), while in AMD group, no statistically significant difference in serum CFH concentration between different genotypes.Conclusion: CFH Y402H polymorphism does not confer risk of AMD in Egyptian patients. Further larger scaled studies are needed to confirm CFH role in AMD.

Genetic association with intravitreal ranibizumab response for neovascular age-related macular degeneration in Hispanic population.

BACKGROUND/PURPOSE:Age-related macular degeneration (AMD) is the leading cause of visual impairment in patients over 55 years. Currently, the most common therapies for neovascular AMD (nAMD) are intravitreal antiangiogenics. Studies suggest that genetic factors influence on antiangiogenics therapy outcomes. The purpose of this work was to establish the association between complement factor H (CFH) (Y402H), age-related maculopathy susceptibility 2 (ARMS2) (A69S), and high-temperature requirement factor A1 (HTRA1) (rs11200638) polymorphisms and the response to treatment with ranibizumab in patients with nAMD.METHODS:A cross-sectional study with 61 eyes with nAMD treated with ranibizumab was performed. Association between polymorphisms from CFH, ARMS2, and HTRA1 with the response to treatment was established.RESULTS:The mean age of patients was 76.6 (51–91) years. Only 37.7% of patients had a functional response and 26.2% had an anatomic response. TT polymorphism Y402H from CFH gene was associated with an increased likelihood of functional response to treatment. Otherwise, there was not a statistically significant association between anatomic and functional response to gene polymorphisms rs11200638 from HTRA1 and rs10490924 from ARMS 2.CONCLUSIONS:This study suggests that the response to intravitreal antiangiogenic therapy with ranibizumab was not associated to main polymorphisms from genes HTRA1 and ARMS2. However, it was found that the response to treatment differed according to CFH genotype, suggesting that further investigations are needed to establish if patients with the CC and TC genotype may need to be monitored more closely for disease recurrence than the TT genotype.

The ARMS2 A69S Polymorphism Is Associated with Delayed Rod-Mediated Dark Adaptation in Eyes at Risk for Incident Age-Related Macular Degeneration

To examine the association between sequence variants in genetic risk factors for age-related macular degeneration (AMD) and delayed rod-mediated dark adaptation (RMDA), the first functional biomarker for incident AMD, in older adults with normal macular health and early AMD. Cross-sectional. Adults 60 years of age or older showing normal macular health (defined as both eyes at step 1 on the Age-Related Eye Disease Study 9-step AMD classification system) and those with AMD in one or both eyes (defined as steps 2-9). Single nucleotide polymorphisms were genotyped in the complement factor H (CFH) and ARMS2 genes using a Taqman assay. Rod-mediated dark adaptation was assessed in 1 eye after photobleach with targets centered at 5° on the inferior vertical meridian. Rate of dark adaptation was defined by rod intercept time (RIT), duration (in minutes) required for sensitivity to reach a criterion sensitivity level in the latter half of the second component of rod recovery. Associations between CFH and ARMS2 polymorphisms and RMDA were adjusted for age and smoking. Rod intercept time. The sample consisted of 543 participants having both genotype and RIT determination; 408 showed normal macular health and 135 demonstrated AMD, most having early AMD (124 of 135). For the combined sample, higher RIT (slower RMDA) was observed for both the A69S variant in ARMS2 and the Y402H variant in CFH (adjusted P= 0.0001 and P= 0.0023, respectively). For healthy participants, the A69S variant in ARMS2 was associated with higher RIT (adjusted P= 0.0011), whereas the Y402H variant in CFH was not (adjusted P=0.2175). For AMD patients, the A69S variant of ARMS2 and the Y402H variant of CFH were associated with higher RIT (adjusted P=0.0182 and P= 0.0222, respectively). Those with a larger number of high-risk ARMS2 and CFH alleles showed higher RIT, in both healthy and AMD groups (adjusted P= 0.0002 and P < 0.0001, respectively). We report a novel association wherein older adults with high-risk ARMS2 and CFH genotypes are more likely to demonstrate delayed RMDA, the first functional biomarker for incident early AMD. Before the AMD clinical phenotype is present, those showing normal macular health with the ARMS2 A69S allele demonstrate delayed RMDA. Understanding ARMS2 function is a research priority.

CFH and ARMS2 Polymorphisms Interact with Zinc Supplements in Cognitive Impairment in the Women's Health Initiative Hormone Trial.

An interaction between genetic variants in complement factor H (CFH) and age-related maculopathy susceptibility 2 (ARMS2) and high-dose zinc supplementation on progression to advanced age-related macular degeneration (AMD) exists. Because cognitive impairment (CI) is associated with AMD, we used data from the Women's Health Initiative (WHI) to search for a zinc/genetics interaction. To study the interaction of chronic zinc supplementation with genetic variants in CFH and ARMS2 on the development of CI. Zinc dietary supplements, CFH and ARMS2 genotypes, and serial mental status was analyzed in participants with available genetic data (n = 7,483). Cognition was assessed using the Modified Mini-Mental State Examination. The development of CI over 5 years was analyzed by genotype and zinc intake using a repeated measures logistic regression model. Zinc supplementation of approximately 15 mg/day was associated with decreased development of CI in women with 1 or 2 CFH and no ARMS2 risk alleles (OR = 0.46: 1 CFH risk allele; 0.20: 2 CFH risk alleles; p = 0.002). Low-dose zinc (approximately 15 mg) is associated with reduced CI in women with 2 CFH and 0 ARMS2 AMD risk alleles. This interaction is opposite in direction to that observed in AMD, where patients with 2 CFH and 0 ARMS2 risk alleles had increased progression to neovascular AMD if treated with 80 mg/day of zinc. This may be due to a zinc dose-response or to a fundamental difference in the role of zinc in the progression of early CI versus advanced AMD.

CFH and ARMS2 genetic risk determines progression to neovascular age-related macular degeneration after antioxidant and zinc supplementation

We evaluated the influence of an antioxidant and zinc nutritional supplement [the Age-Related Eye Disease Study (AREDS) formulation] on delaying or preventing progression to neovascular AMD (NV) in persons with age-related macular degeneration (AMD). AREDS subjects (n = 802) with category 3 or 4 AMD at baseline who had been treated with placebo or the AREDS formulation were evaluated for differences in the risk of progression to NV as a function of complement factor H (CFH) and age-related maculopathy susceptibility 2 (ARMS2) genotype groups. We used published genetic grouping: a two-SNP haplotype risk-calling algorithm to assess CFH, and either the single SNP rs10490924 or 372_815del443ins54 to mark ARMS2 risk. Progression risk was determined using the Cox proportional hazard model. Genetics-treatment interaction on NV risk was assessed using a multiiterative bootstrap validation analysis. We identified strong interaction of genetics with AREDS formulation treatment on the development of NV. Individuals with high CFH and no ARMS2 risk alleles and taking the AREDS formulation had increased progression to NV compared with placebo. Those with low CFH risk and high ARMS2 risk had decreased progression risk. Analysis of CFH and ARMS2 genotype groups from a validation dataset reinforces this conclusion. Bootstrapping analysis confirms the presence of a genetics-treatment interaction and suggests that individual treatment response to the AREDS formulation is largely determined by genetics. The AREDS formulation modifies the risk of progression to NV based on individual genetics. Its use should be based on patient-specific genotype.

Association of the CFH Y402H Polymorphism with the 1-Year Response of Exudative AMD to Intravitreal Anti-VEGF Treatment in the Brazilian Population

Aim: Evidence of the relationship between the polymorphism of the complement factor H (CFH) gene at position 402 (Y402H) and the response to the treatment of wet AMD is controversial. The aim of this study was to compare the functional and morphological 1-year evolution of patients with exudative AMD treated with antivascular endothelial growth factor (VEGF) drugs with the CFH Y402H polymorphism in the Brazilian population. Methods: Forty-six patients treated for wet AMD with bevacizumab or ranibizumab in a pro re nata regimen were included. The evolution of best-corrected visual acuity (BCVA) and central retinal thickness (CRT), and the number of injections over 1 year of follow-up were correlated with CFH genotypes. Results: The analysis of variance for the difference between the BCVA denoted as log_MAR (logarithm of the minimum angle of resolution) values showed an improvement at 1 year when compared to baseline (p = 0.039). Profile contrast analysis showed that this difference was significant only in the group without the C allele (p = 0.049), without significance in patients presenting with the risk allele (p = 0.241). CRT showed a mean reduction at 1 year compared to baseline (p < 0.001). Significant differences in the profile contrast test were found in the group without the C allele (p < 0.001) and in patients with the risk allele (p = 0.002). No difference was found in the number of injections among the different groups (p = 0.787). Conclusions: The presence of the risk allele of the Y402H polymorphism in the CFH gene was related to a less favorable evolution over 1 year in this sample of the Brazilian population with exudative AMD who were being treated with anti-VEGF drugs. In agreement with similar previous studies, this study concludes that the CFH risk genotypes may affect the disease response to treatment.

Vitamin D Status and Prevalent Early Age-Related Macular Degeneration in African Americans and Caucasians: The Atherosclerosis Risk in Communities (ARIC) Study.

Vitamin D status has been hypothesized to protect against development of early age-related macular degeneration (AMD) via its anti-inflammatory properties and its possible beneficial influence on blood pressure control. We investigated the association between vitamin D status and prevalent early AMD in a community-based cohort. This was a cross-sectional study. This was a secondary data analysis of already existing data from the Atherosclerosis Risk in Communities Study (ARIC) cohort collected from 1990 to 1995. There were 9,734 (7,779 Caucasians, 1,955 African American) ARIC participants (aged 46 to 70 at visit 2 [1990-1992]) with 25(OH)D data available at visit 2, AMD assessment at visit 3 (1993-1995), and complete covariate data. Vitamin D status was assessed with serum 25-hydroxyvitamin D (25(OH)D) concentrations from bloods drawn at visit 2. Prevalent, early AMD (n=511) was assessed at visit 3 (1993-95) with nonmydriatic retinal photographs of one randomly chosen eye. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for early AMD by categories of 25(OH)D in nmol/L (deficient <30, inadequate 30-<50, and two categories of adequate status: 50-<75 and ≥75). Linear trend was estimated using continuous 25(OH)D concentrations. ORs were adjusted for age, race, and smoking status. We further adjusted for hypertension status to examine if vitamin D status influenced early AMD via its effects on blood pressure. Exploratory analyses of effect modification by age, sex, race and high risk genotypes [Y402H complement factor H (CFH) rs1061170 and the A69S age-related maculopathy susceptibility 2 (ARMS2) rs10490924 polymorphisms] were conducted. The prevalence of early AMD was 5%, and 5% of participants were vitamin D deficient. The adjusted OR (95% CIs) for early AMD among those with adequate (≥75 nmol/L) compared to deficient (<30 nmol/L) vitamin D status was 0.94 (0.59-1.50), p-trend=0.86. Further adjustment for hypertension status did not influence results (OR [95% CI]=0.95 [0.59-1.52], p-trend=0.84). Results did not vary significantly by age, race, sex, early AMD subtype (soft drusen or retinal pigment epithelium depigmentation), or ARMS2 genotype. Results did not vary significantly by CFH genotype in African Americans. The p for multiplicative interaction between 25(OH)D and CFH genotype was 0.06 in Caucasians, but OR [95% CIs] for AMD by vitamin D status were similar in each CFH genotype and not statistically significant. Vitamin D status was not associated with early AMD in this cohort sample.

Clinical study of the correlation between complement factor H polymorphism and age-related macular degeneration.

This study aimed to investigate the correlation between age-related macular degeneration (AMD) of the liver-kidney yin-deficiency type and complement factor H (CFH) polymorphism, and to determine whether the C allele of the T1277C (Y402H) variant is a risk factor for this condition. We performed a case-control investigation of 60 patients with liver-kidney yin-deficiency AMD and 60 normal control subjects. Peripheral blood was collected from each participant for DNA extraction. Following amplification by polymerase chain reaction, the DNA samples were sequenced, and polymorphism of the CFH gene was examined. Data were analyzed with the chi-square test, with P < 0.05 signifying statistical significance. The frequency of the C allele was significantly higher in the wet than in the dry AMD group (P = 0.044). In addition, the TC and CC genotypes were markedly more common in the former than in the control group (P = 0.013), and there was a significant difference in the distribution of the T and C alleles between wet AMD patients and control subjects (P < 0.05). Based on this, we conclude that liver-kidney yin-deficiency AMD is associated with the C allele and TC and CC genotypes of the CFH Y402H polymorphism. Among patients with this condition, CFH genotypes were normally distributed. The principal CFH genotypes that induce liver-kidney yin-deficiency AMD are the mutant homozygote CC and heterozygote TC forms. Moreover, C allele carriers are at higher risk of developing this disease.

Predictors of Response to Intravitreal Anti–Vascular Endothelial Growth Factor Treatment of Age-Related Macular Degeneration

To identify factors that influence visual and anatomic response to treatment with intravitreal anti-vascular endothelial growth factor (VEGF) for neovascular age-related macular degeneration (AMD). Observational cohort study. Seventy-two patients were included in this study. Best-corrected Snellen visual acuity (VA) and central foveal thickness measured on optical coherence tomography (OCT) at time of treatment and post-treatment follow-up visits were recorded. Associations between demographic, behavioral, and genetic risk factors and the 2 outcomes were analyzed using mixed-effects linear regression models. Two loci in complement factor H (CFH) were included in a risk score to determine the association between CFH risk and improvement in VA and central foveal thickness. There was a small improvement in VA following anti-VEGF treatment (mean: 3.7 ± 3.0 letters), which was not statistically significant. Significant improvement in VA was observed for the nonrisk CFH Y402H genotype (P < .001) and for a low CFH risk score (P = .019). Regarding the outcome of change in central foveal thickness, improvement was noted in all genotype groups, but reduction after treatment was significantly higher in the low CFH risk score group (P = .033). A significant improvement in mean VA was seen among smokers (P < .001), but this relationship was not observed for central foveal thickness. After anti-VEGF therapy, significant improvement in VA was observed for low-risk CFH genotypes and subjects with a low risk score. There was a statistically significant reduction in central foveal thickness overall, and subjects with a low CFH risk score improved more than the high-risk group.

Joint Associations of Diet, Lifestyle, and Genes with Age-Related Macular Degeneration

Unhealthy lifestyles have been associated with increased odds for age-related macular degeneration (AMD). Whether this association is modified by genetic risk for AMD is unknown and was investigated. Interactions between healthy lifestyles AMD risk genotypes were studied in relation to the prevalence of AMD, assessed 6 years later. Women 50 to 79 years of age in the Carotenoids in Age-Related Eye Disease Study with exposure and AMD data (n=1663). Healthy lifestyle scores (0-6 points) were assigned based on Healthy Eating Index scores, physical activity (metabolic equivalent of task hours/week), and smoking pack years assessed in 1994 and 1998. Genetic risk was based on Y402H in complement factor H (CFH) and A69S in age-related maculopathy susceptibility locus 2 (ARMS2). Additive and multiplicative interactions in odds ratios were assessed using the synergy index and a multiplicative interaction term, respectively. AMD presence and severity were assessed from grading of stereoscopic fundus photographs taken in 2001-2004. AMD was present in 337 women, 91% of whom had early AMD. The odds of AMD were 3.3 times greater (95% confidence interval [CI], 1.8-6.1) in women with both low healthy lifestyle score (0-2) and high-risk CFH genotype (CC), relative to those who had low genetic risk (TT) and high healthy lifestyle scores (4-6). There were no significant additive (synergy index [SI], 1.08; 95% CI, 0.70-1.67) or multiplicative (Pinteraction=0.94) interactions in the full sample. However, when limiting the sample to women with stable diets before AMD assessment (n=728) the odds for AMD associated with low healthy lifestyle scores and high-risk CFH genotype were strengthened (odds ratio, 4.6; 95% CI, 1.8-11.6) and the synergy index was significant (SI, 1.34; 95% CI, 1.05-1.70). Adjusting for dietary lutein and zeaxanthin attenuated, and therefore partially explained, the joint association. There were no significant additive or multiplicative interactions for ARMS2 and lifestyle score. Having unhealthy lifestyles and 2 CFH risk alleles increased AMD risk (primarily in the early stages), in an or additive or greater (synergistic) manner. However, unhealthy lifestyles increased AMD risk regardless of AMD risk genotype.

Systemic and Ocular Long Pentraxin 3 in Patients with Age-Related Macular Degeneration.

Age-related macular degeneration (AMD) has been associated with both systemic and ocular alterations of the immune system. In particular dysfunction of complement factor H (CFH), a soluble regulator of the alternative pathway of the complement system, has been implicated in AMD pathogenesis. One of the ligands for CFH is long pentraxin 3 (PTX3), which is produced locally in the retinal pigment epithelium (RPE). To test the hypothesis that PTX3 is relevant to retinal immunohomeostasis and may be associated with AMD pathogenesis, we measured plasma PTX3 protein concentration and analyzed the RPE/choroid PTX3 gene expression in patients with AMD. To measure the ability of RPE cells to secrete PTX3 in vitro, polarized ARPE-19 cells were treated with activated T cells or cytokines (interferon (IFN)-gamma and/or tumor necrosis factor (TNF)-alpha) from the basolateral side; then PTX3 protein concentration in supernatants and PTX3 gene expression in tissue lysates were quantified. Plasma levels of PTX3 were generally low and did not significantly differ between patients and controls (P=0.307). No statistically significant difference was observed between dry and exudative AMD nor was there any correlation with hsCRP or CFH genotype. The gene expression of PTX3 increased in RPE/choroid with age (P=0.0098 macular; P=0.003 extramacular), but did not differ between aged controls and AMD patients. In vitro, ARPE-19 cells increased expression of the PTX3 gene as well PTX3 apical secretions after stimulation with TNF-alpha or activated T cells (P<0.01). These findings indicate that PTX3 expressed in the eye cannot be detected systemically and systemic PTX3 may have little or no impact on disease progression, but our findings do not exclude that locally produced PTX3 produced in the posterior segment of the eye may be part of the AMD immunopathogenesis.

No Clinically Significant Association between CFH and ARMS2 Genotypes and Response to Nutritional Supplements: AREDS Report Number 38

To determine whether genotypes at 2 major loci associated with late age-related macular degeneration (AMD), complement factor H (CFH) and age-related maculopathy susceptibility 2 (ARMS2), influence the relative benefits of Age-Related Eye Disease Study (AREDS) supplements. Unplanned retrospective evaluation of a prospective, randomized, placebo-controlled clinical trial of vitamins and minerals for the treatment of AMD. AREDS participants (mean age, 69 years) who were at risk of developing late AMD and who were randomized to the 4 arms of AREDS supplement treatment. Analyses were performed using the Cox proportional hazards model to predict progression to late AMD (neovascular or central geographic atrophy). Statistical models, adjusted for age, gender, smoking status, and baseline AMD severity, were used to examine the influence of genotypes on the response to therapy with 4 randomly assigned arms of AREDS supplement components: placebo, antioxidants (vitamin C, vitamin E, β-carotene), zinc, or a combination. The influence of the genotype on the relative treatment response to the randomized components of the AREDS supplement, measured as progression to late AMD. Of the 1237 genotyped AREDS participants of white ethnicity, late AMD developed in 385 (31.1%) during the mean follow-up of 6.6 years. As previously demonstrated, CFH genotype (P = 0.005), ARMS2 (P< 0.0001), and supplement were associated individually with progression to late AMD. An interaction analysis found no evidence that the relative benefits of AREDS supplementation varied by genotype. Analysis of (1) CFH rs1061170 and rs1410996 combined with ARMS2 rs10490924 with the 4 randomly assigned arms of AREDS supplement and (2) analysis of the combination of CFH rs412852 and rs3766405 with ARMS2 c.372_815del443ins54 with the AREDS components resulted in no interaction (P = 0.06 and P = 0.45, respectively, before multiplicity adjustment). The AREDS supplements reduced the rate of AMD progression across all genotype groups. Furthermore, the genotypes at the CFH and ARMS2 loci did not statistically significantly alter the benefits of AREDS supplements. Genetic testing remains a valuable research tool, but these analyses suggest it provides no benefits in managing nutritional supplementation for patients at risk of late AMD.

Misclassification Can Explain Most Apparent Regression of Age-Related Macular Degeneration: Results From Multistate Models With Misclassification

To investigate the impact of misclassification of age-related macular degeneration (AMD) on the baseline intensity and estimated effects of age, sex, and the Y402H variant in the complement factor H (CFH) gene on incidence, progression, and regression of AMD. The Beaver Dam Eye Study, a longitudinal population-based study of age-related eye diseases conducted in the city and township of Beaver Dam, Wisconsin, performed examinations every 5 years during a 20-year period (1988-1990 through 2008-2010). Study participants (N = 4379) aged 43 to 86 years at the baseline examination had retinal photographs taken at baseline and up to four subsequent examinations. Multistate models with misclassification in continuous time were used to model the effects of age, sex, and CFH genotype on incidence, progression, and regression of AMD and mortality. After accounting for AMD misclassification, the occurrence of any AMD regression was rare (1%-4%), while it was relatively common (14%-21%) in models that do not account for misclassification. Failure to account for misclassification attenuated estimated age effects on incidence and progression to moderately severe early AMD and attenuated estimated CFH effects on incidence and progressions to moderately severe and severe early AMD. Apparent regression of AMD can largely, if not completely, be explained by misclassification. Estimated age effects on incidence and progression to moderately severe early AMD and estimated CFH effects on incidence and progressions to moderately severe and severe early AMD were attenuated in multistate models that did not account for misclassification.

Proof of Concept, Randomized, Placebo-Controlled Study of the Effect of Simvastatin on the Course of Age-Related Macular Degeneration

BackgroundHMG Co-A reductase inhibitors are ubiquitous in our community yet their potential role in age-related macular degeneration (AMD) remains to be determined.Methodology/Principal Findings Objectives: To evaluate the effect of simvastatin on AMD progression and the effect modification by polymorphism in apolipoprotein E (ApoE) and complement factor H (CFH) genes. Design: A proof of concept double-masked randomized controlled study. Participants: 114 participants aged 53 to 91 years, with either bilateral intermediate AMD or unilateral non-advanced AMD (with advanced AMD in fellow eye), BCVA≥20/60 in at least one eye, and a normal lipid profile. Intervention: Simvastatin 40 mg/day or placebo, allocated 1∶1. Main outcome measures: Progression of AMD either to advanced AMD or in severity of non-advanced AMD. Results. The cumulative AMD progression rates were 70% in the placebo and 54% in the simvastatin group. Intent to treat multivariable logistic regression analysis, adjusted for age, sex, smoking and baseline AMD severity, showed a significant 2-fold decrease in the risk of progression in the simvastatin group: OR 0.43 (0.18–0.99), p = 0.047. Post-hoc analysis stratified by baseline AMD severity showed no benefit from treatment in those who had advanced AMD in the fellow eye before enrolment: OR 0.97 (0.27–3.52), p = 0.96, after adjusting for age, sex and smoking. However, there was a significant reduction in the risk of progression in the bilateral intermediate AMD group compared to placebo [adjusted OR 0.23 (0.07–0.75), p = 0.015]. The most prominent effect was observed amongst those who had the CC (Y402H) at risk genotype of the CFH gene [OR 0.08 (0.02–0.45), p = 0.004]. No evidence of harm from simvastatin intervention was detected.Conclusion/SignificanceSimvastatin may slow progression of non-advanced AMD, especially for those with the at risk CFH genotype CC (Y402H). Further exploration of the potential use of statins for AMD, with emphasis on genetic subgroups, is warranted.Trial RegistrationAustralian New Zealand Clinical Trial Registry (ANZCTR) ACTRN1260500032065

Age-related Macular Degeneration Is Associated with Increased Proportion of CD56+ T Cells in Peripheral Blood

To examine the association between age-related changes in the T-cell compartment and prevalence of age-related macular degeneration (AMD). Case-control study. A total of 117 AMD cases and 106 controls were included prospectively. Fresh-drawn peripheral blood samples were processed for flow cytometric analysis of T-cell populations. Plasma samples were analyzed for anti-cytomegalovirus (CMV) immunoglobulin (Ig)G and complement factor H (CFH) Y402H genotype. The diagnosis of AMD was made according to the Clinical Age-Related Maculopathy Staging System. Association between frequency of aged T cells and prevalence of AMD. The prevalence of AMD was associated with distinct age-related changes in the T-cell compartment. Specifically, the patients with AMD had an increased frequency of CD28(-) T cells that expressed the CD56 surface marker (patients, 34.9% vs. aged controls, 25.8%; P = 0.002). Participants in the highest tertile of CD56(+) CD28(-) T cells had an odds ratio (OR) for the presence of AMD of 3.2 (95% confidence interval [CI], 1.2-8.8) after adjustment for CFH genotype, anti-CMV IgG positivity, age, sex, and smoking history. The adjusted OR of the presence of AMD for persons having at least 1 CFH H402 risk allele increased from 3.5 (95% CI, 1.5-8.1) to 13.3 (95% CI, 3.3-53.6) for persons with at least 1 CFH H402 risk allele and above the median level of CD56(+) CD28(-) T cells. We found increased levels of circulating aged CD56(+) CD28(-) T cells in patients with AMD. Although this supports the notion of AMD as a systemic disease, it also suggests that the adaptive immune system is implicated in its pathogenesis.

Incidence and Progression of Geographic Atrophy: Observations from a Population-based Cohort

To examine early age-related macular degeneration (AMD) lesion characteristics and risk factors associated with the long-term development and progression of geographic atrophy (GA). Population-based cohort. Of 3654 participants aged ≥49 years in the Blue Mountains Eye Study, 75.8%, 76.7%, and 56.1% of survivors attended the 5-, 10-, and 15-year follow-up examinations, respectively. Retinal photographs were taken at each visit. Incident GA was confirmed using a side-by-side grading method. Computer planimetry was used to measure the area involved by GA. Fast and slow/normal progression rates were defined as GA area enlargement by ≥2 and <2 mm(2)/year, respectively. Incident GA was estimated using the Kaplan-Meier product-limit method. Early AMD lesion characteristics were assessed for association with GA incidence using eye-specific data and generalized estimating equation models adjusting for age, current smoking, and presence of risk alleles of the complement factor H (CFH) or age-related maculopathy susceptibility 2 (ARMS2) genes, genotyped or imputed using genome-wide scan data. Incidence and progression of GA. By excluding 41 subjects with GA at baseline, of 2503 participants at risk of GA, incident pure GA (without coexisting neovascular AMD lesions) was confirmed in 57 participants, with a 15-year incidence of 3.6%. Baseline early AMD lesion characteristics associated with GA incidence included drusen type (soft indistinct: odds ratio [OR], 59.0; 95% confidence interval [CI], 20.4-171.0; reticular drusen: OR, 13.9; 95% CI, 4.0-47.6); drusen location within a 500-μm radius of the fovea (OR, 15.1; 95% CI, 7.4-30.8); drusen area greater than 375 μm in diameter (OR, 10.1; 95% CI, 4.0-25.6); presence of retinal pigment epithelial depigmentation (OR, 9.0; 95% CI, 4.1-19.8); or hyperpigmentation (OR, 12.0; 95% CI, 6.1-23.5), referenced to subjects with no or hard drusen only. Fast progression was more frequent among current smokers at baseline, subjects with the CFH or ARMS2 risk genotypes, and pseudophakic eyes. Early AMD lesion characteristics (type, location, area involved) were strongly associated with higher long-term risk of developing GA independent of age, smoking, and AMD genetic susceptibility from the CFH or ARMS2 genes. Known AMD risk factors also were more frequently present among quickly progressing GA cases. Proprietary or commercial disclosure may be found after the references.

Y402H Polymorphism in Complement Factor H and Age-Related Macular Degeneration in the Tunisian Population

To evaluate a possible association between the complement factor H (CFH) Y402H polymorphism and susceptibility to age-related macular degeneration (AMD) in the Tunisian population, as well as the impact of the genotype distribution among different phenotypes and the response to treatment with intravitreal bevacizumab, exon 9 of CFH was analyzed for the Y402H polymorphism by direct sequencing in 135 healthy controls and 127 sporadic unrelated AMD patients classified into the following groups: 12 atrophic AMD (group G1), 115 exudative AMD (G2) and 10 AMD patients who had fibrovascular scarring (G3) that did not allow a precise grading of the phenotype. Seventy patients in G2 were treated with 1.25 mg intravitreal bevacizumab at 6-week intervals until choroidal neovascularization (CNV) was no longer active. The frequency of the CFH 402H allele was significantly higher in AMD patients than in controls (p = 2.62 × 10^–16). However, subgroup analysis does not reveal any association between the variant allele H and phenotypes of AMD or CNV. Also, there was no significant difference in response to bevacizumab treatment according to Y402H CFH genotype (p = 0.59). A strong association of the 402H allele with susceptibility to AMD in the Tunisian population was confirmed; however, this variant does not appear to be involved in the clinical progression of this disease or in the postintravitreal bevacizumab response.