Age-Related Macular Degeneration and Cardiovascular Diseases: Revisiting the Common Soil Theory

Life's Essential 8, Genetic Susceptibility, and the Risk of Age-Related Macular Degeneration: A Prospective Cohort Study

Purpose

We determined the association between Life's Essential 8 (LE8) scores and AMD incidence and ascertained whether genetic susceptibility modifies it.

Methods

This prospective cohort study included 268,634 UK Biobank study participants with high, moderate, or low cardiovascular health based on LE8 scores. High and low cardiovascular health corresponded to the lowest and highest cardiovascular disease risks, respectively. The hazard ratios (HRs) and 95% confidence intervals (CIs) for AMD were estimated using Cox proportional hazards models. The dose-response relationships were evaluated using restricted cubic spline analysis. Stratified analyses using the AMD-polygenic risk score categories were used to assess potential modification. A composite variable combined LE8 and AMD-polygenic risk to examine their joint effects.

Results

Over an average of 13.76 years, 5253 participants developed AMD. Compared with the lowest cardiovascular health, moderate and high cardiovascular health had adjusted HRs of 0.86 (95% CI, 0.76, 0.97) and 0.79 (0.69, 0.91), respectively. Each standard deviation increase in the LE8 score corresponded to an HR of 0.93 (0.91, 0.96). The LE8 behavior (HR = 0.94 [0.91, 0.96]) and biological (HR = 0.97 [0.95, 1.00]) subscale scores were inversely associated with AMD, whereas the blood lipids component was positively associated (HR = 1.07 [1.04, 1.10]). The AMD-polygenic risk and LE8 scores showed no significant interaction. The HR for having low AMD-polygenic risk and high cardiovascular health relative to having high AMD-polygenic risk and low cardiovascular health was 0.47 (0.37, 0.58).

Conclusions

Maintaining good cardiovascular health can reduce AMD incidence regardless of genetic background.

Cardiovascular Autonomic Function and Progression of Age-Related Macular Degeneration in The Irish Longitudinal Study of Ageing (TILDA)

Purpose

To examine if changes in hemodynamic measures during an orthostatic challenge were associated with progression of age-related macular degeneration (AMD) over a 4-year period in The Irish Longitudinal Study on Ageing.

Methods

Participants with AMD who underwent an active stand (AS) test at wave 1 (2009/2010) and retinal photographs at both wave 1 and wave 3 (2014/2015) were included (N = 159: 121 with no AMD progression and 38 with progression). Beat-to-beat hemodynamic data were non-invasively collected using a Finometer MIDI device during the AS at wave 1, recording systolic blood pressure (sBP), diastolic blood pressure (dBP), mean arterial pressure (MAP), and heart rate. Cardiac output, stroke volume, and total peripheral resistance (TPR) were derived from these measures. Baseline characteristics were compared between groups with and without AMD progression. Mixed-effects linear regression models were used to assess the association between changes in hemodynamic parameters during the AS and AMD progression, controlling for known AMD-associated risk factors.

Results

At baseline, increasing age and lower dBP were significantly associated with AMD progression. Mixed-effects models for the period between standing and 10 seconds post-stand revealed significant associations with AMD progression with a steeper drop in dBP and a slower drop in TPR. Between 10 and 20 seconds post-stand, AMD progression was significantly associated with less pronounced reduction in heart rate.

Conclusions

These observational data suggest that impaired hemodynamic responses within the first 20 seconds of orthostasis may be associated with the progression of AMD.

Phenome- and genome-wide analyses of retinal optical coherence tomography images identify links between ocular and systemic health

The human retina is a multilayered tissue that offers a unique window into systemic health. Optical coherence tomography (OCT) is widely used in eye care and allows the noninvasive, rapid capture of retinal anatomy in exquisite detail. We conducted genotypic and phenotypic analyses of retinal layer thicknesses using macular OCT images from 44,823 UK Biobank participants. We performed OCT layer cross-phenotype association analyses (OCT-XWAS), associating retinal thicknesses with 1866 incident conditions (median 10-year follow-up) and 88 quantitative traits and blood biomarkers. We performed genome-wide association studies (GWASs), identifying inherited genetic markers that influence retinal layer thicknesses and replicated our associations among the LIFE-Adult Study (N = 6313). Last, we performed a comparative analysis of phenome- and genome-wide associations to identify putative causal links between retinal layer thicknesses and both ocular and systemic conditions. Independent associations with incident mortality were detected for thinner photoreceptor segments (PSs) and, separately, ganglion cell complex layers. Phenotypic associations were detected between thinner retinal layers and ocular, neuropsychiatric, cardiometabolic, and pulmonary conditions. A GWAS of retinal layer thicknesses yielded 259 unique loci. Consistency between epidemiologic and genetic associations suggested links between a thinner retinal nerve fiber layer with glaucoma, thinner PS with age-related macular degeneration, and poor cardiometabolic and pulmonary function with a thinner PS. In conclusion, we identified multiple inherited genetic loci and acquired systemic cardio-metabolic-pulmonary conditions associated with thinner retinal layers and identify retinal layers wherein thinning is predictive of future ocular and systemic conditions.

Prevalence and determinants of subretinal drusenoid deposits in patients' first-degree relatives

PURPOSE

Subretinal drusenoid deposits (SDDs) are distinct extracellular alteration anterior to the retinal pigment epithelium (RPE). Given their commonly uniform phenotype, a hereditary predisposition seems likely. Hence, we aim to investigate prevalence and determinants in patients' first-degree relatives.

METHODS

We recruited SDD outpatients at their visits to our clinic and invited their relatives. We performed a full ophthalmic examination including spectral domain-optical coherence tomography (SD-OCT) and graded presence, disease stage of SDD as well as percentage of infrared (IR) en face area affected by SDD. Moreover, we performed genetic sequencing and calculated a polygenic risk score (PRS) for AMD. We conducted multivariable regression models to assess potential determinants of SDD and associations of SDD with PRS.

RESULTS

We included 195 participants, 123 patients (mean age 81.4 ± 7.2 years) and 72 relatives (mean age 52.2 ± 14.2 years), of which 7 presented SDD, resulting in a prevalence of 9.7%. We found older age to be associated with SDD presence and area in the total cohort and a borderline association of higher body mass index (BMI) with SDD presence in the relatives. Individuals with SDD tended to have a higher PRS, which, however, was not statistically significant in the multivariable regression.

CONCLUSION

Our study indicates a potential hereditary aspect of SDD and confirms the strong association with age. Based on our results, relatives of SDD patients ought to be closely monitored for retinal alterations, particularly at an older age. Further longitudinal studies with larger sample size and older relatives are needed to confirm or refute our findings.

Association of lipid-lowering drugs and antidiabetic drugs with age-related macular degeneration: a meta-analysis in Europeans

BACKGROUND/AIMS

To investigate the association of commonly used systemic medications with prevalent age-related macular degeneration (AMD) in the general population.

METHODS

We included 38 694 adults from 14 population-based and hospital-based studies from the European Eye Epidemiology consortium. We examined associations between the use of systemic medications and any prevalent AMD as well as any late AMD using multivariable logistic regression modelling per study and pooled results using random effects meta-analysis.

RESULTS

Between studies, mean age ranged from 61.5±7.1 to 82.6±3.8 years and prevalence ranged from 12.1% to 64.5% and from 0.5% to 35.5% for any and late AMD, respectively. In the meta-analysis of fully adjusted multivariable models, lipid-lowering drugs (LLD) and antidiabetic drugs were associated with lower prevalent any AMD (OR 0.85, 95% CI=0.79 to 0.91 and OR 0.78, 95% CI=0.66 to 0.91). We found no association with late AMD or with any other medication.

CONCLUSION

Our study indicates a potential beneficial effect of LLD and antidiabetic drug use on prevalence of AMD across multiple European cohorts. Our findings support the importance of metabolic processes in the multifactorial aetiology of AMD.

Mechanistic Insight into Age-Related Macular Degeneration (AMD): Anatomy, Epidemiology, Genetics, Pathogenesis, Prevention, Implications, and Treatment Strategies to Pace AMD Management

One of the most complicated eye disorders is age-related macular degeneration (AMD) which is the leading cause of irremediable blindness all over the world in the elderly. AMD is classified as early stage to late stage (advanced AMD), in which this stage is divided into the exudative or neovascular form (wet AMD) and the nonexudative or atrophic form (dry AMD). Clinically, AMD primarily influences the central area of retina known as the macula. Importantly, the wet form is generally associated with more severe vision loss. AMD has a systemic component, where many factors, like aging, genetic, environment, autoimmune and non-autoimmune disorders are associated with this disease. Additionally, healthy lifestyles, regular exercise, maintaining a normal lipid profile and weight are crucial to decreasing the risk of AMD. Furthermore, therapeutic strategies for limiting AMD should encompass a variety of factors to avoid and improve drug interventions, and also need to take into account personalized genetic information. In conclusion, with the development of technology and research progress, visual impairment and legal blindness from AMD have been substantially reduced in incidence. This review article is focused on identifying and developing the knowledge about the association between genetics, and etiology with AMD. We hope that this review will encourage researchers and lecturers, open new discussions, and contribute to a better understanding of AMD that improves patients' visual acuity, and upgrades the quality of life of AMD patients.

Insights into human health from phenome- and genome-wide analyses of UK Biobank retinal optical coherence tomography phenotypes

The human retina is a complex multi-layered tissue which offers a unique window into systemic health and disease. Optical coherence tomography (OCT) is widely used in eye care and allows the non-invasive, rapid capture of retinal measurements in exquisite detail. We conducted genome- and phenome-wide analyses of retinal layer thicknesses using macular OCT images from 44,823 UK Biobank participants. We performed phenome-wide association analyses, associating retinal thicknesses with 1,866 incident ICD-based conditions (median 10-year follow-up) and 88 quantitative traits and blood biomarkers. We performed genome-wide association analyses, identifying inherited genetic markers which influence the retina, and replicated our associations among 6,313 individuals from the LIFE-Adult Study. And lastly, we performed comparative association of phenome- and genome- wide associations to identify putative causal links between systemic conditions, retinal layer thicknesses, and ocular disease. Independent associations with incident mortality were detected for photoreceptor thinning and ganglion cell complex thinning. Significant phenotypic associations were detected between retinal layer thinning and ocular, neuropsychiatric, cardiometabolic and pulmonary conditions. Genome-wide association of retinal layer thicknesses yielded 259 loci. Consistency between epidemiologic and genetic associations suggested putative causal links between thinning of the retinal nerve fiber layer with glaucoma, photoreceptor segment with AMD, as well as poor cardiometabolic and pulmonary function with PS thinning, among other findings. In conclusion, retinal layer thinning predicts risk of future ocular and systemic disease. Furthermore, systemic cardio-metabolic-pulmonary conditions promote retinal thinning. Retinal imaging biomarkers, integrated into electronic health records, may inform risk prediction and potential therapeutic strategies.

Determinants of Incident Atherosclerotic Cardiovascular Disease Events and All-Cause Mortality in Patients With Age-Related Macular Degeneration: Prospective Cohort Study of UK Biobank

PURPOSE

Major risk factors of atherosclerotic cardiovascular disease (ASCVD) and mortality have been well-established in the general population. Our study is aimed at assessing longitudinal relationships between ASCVD risk factors and incident ASCVD events or all-cause mortality in patients with age-related macular degeneration (AMD).

METHODS

Multivariable-adjusted Cox proportional hazards models were used to study the association between cardiovascular risk factors with adjudicated incident ASCVD events and all-cause mortality outcomes followed until 2021. A restricted cubic spline approach was utilized to assess nonlinear associations between potential cardiovascular risk factors and ASCVD or mortality.

RESULTS

We identified 3508 eligible patients [mean (SD) age = 61.45 (6.43) years; 37.76% males] with AMD at baseline. During a median follow-up year of 12, there were 110 cases of ASCVD events and 186 cases of all-cause mortality. After multivariable adjustment, each 10 U/L increase of serum gamma-glutamyl transferase level was linearly associated with incident ASCVD [hazard ratio (HR) = 1.03, 95% CI = 1.00-1.07, Pnonlinear = 0.85)] in AMD. A history of chronic kidney disease (HR = 1.94, 95% CI = 1.09-3.46) and lower vitamin D [HR = 0.98, 95% CI = 0.97-0.99, per nanomoles per liter (nmol/L)] were significantly associated with all-cause mortality in patients with AMD, with the association between vitamin D and all-cause mortality presenting a U shape (Pnonlinear = 0.02). In contrast, risk factors significantly associated with ASCVD and all-cause mortality in healthy controls differed from patients with AMD.

CONCLUSIONS

Our findings demonstrate risk factors associated with ASCVD events and all-cause mortality among individuals with AMD differed from healthy controls and suggest the long-term management of risk factors in patients with AMD.

Review on the Safety and Efficacy of Brolucizumab for Neovascular Age-Related Macular Degeneration From Major Studies and Real-World Data

Frequent antivascular endothelial growth factor injections in neovascular age-related macular degeneration (nAMD) often lead to poor compliance and suboptimal outcomes. A longer-acting agent has been a pressing unmet need until recently. Brolucizumab, an antivascular endothelial growth factor agent, is a single-chain antibody fragment approved by the US Food and Drug Administration (FDA) on October 8, 2019, for treating nAMD. It delivers more molecules at equivalent volumes of aflibercept, thus achieving a longer-lasting effect. We reviewed literature published in English between January 2016 and October 2022 from MEDLINE, PubMed, Cochrane database, Embase, and Google scholar using the keywords: "Brolucizumab, real-world data, intraocular inflammation (IOI), safety, and efficacy". Brolucizumab showed reduced injection frequency, better anatomic outcomes, and noninferior vision gains compared with aflibercept in HAWK and HARRIER studies. However, post hoc studies on brolucizumab revealed a higher-than-expected incidence of IOI, leading to the early termination of 3 studies: MERLIN, RAPTOR, and RAVEN for nAMD, branch retinal vein occlusion, and central retinal vein occlusion, respectively. Contrastingly real-world data showed encouraging outcomes in terms of fewer IOI cases. The subsequent amendment of the treatment protocol resulted in reduced IOI. Thereafter US FDA approved its use in diabetic macular edema on June 1, 2022. Based on major studies and real-world data, this review shows that brolucizumab is effective for treating naive and refractory nAMD. The risk of IOI is acceptable and manageable, but proper preinjection screening and high-vigilance care of IOI are needed. More studies are warranted to evaluate further the incidence, best prevention, and treatment measures for IOI.

The Risk of Age-Related Macular Degeneration Is Reduced in Type 2 Diabetes Patients Who Use Metformin

Background: Whether metformin may reduce the risk of age-related macular degeneration (AMD) requires confirmation. This study compared the risk of AMD between ever users and never users of metformin matched on propensity score (PS) in Taiwanese patients with type 2 diabetes mellitus. Methods: We enrolled study subjects from Taiwan’s National Health Insurance. A total of 423,949 patients with new onset diabetes from 1999 to 2005 were identified. After excluding ineligible patients and enrolling only patients aged between 50 and 79 years, we created 13,303 pairs of ever users and never users of metformin matched on PS. The patients were followed from 1 January 2006 to 31 December 2011. We estimated hazard ratios by Cox regression. Results: AMD was newly diagnosed in 506 ever users and 639 never users. The respective incidence rates (per 100,000 person-years) were 778.72 and 1016.62. The hazard ratio (HR) and 95% confidence interval (CI) for ever versus never users was 0.756 (0.673–0.850). While ever users were categorized by tertiles of cumulative duration (<31.8, 31.8–63.9 and >63.9 months) and cumulative dose (<947.1, 947.1–2193.5 and >2193.5 g) of metformin, a dose–response pattern was observed. For the respective tertiles of cumulative duration, the HRs (95% CIs) were 1.131 (0.961–1.330), 0.821 (0.697–0.967) and 0.464 (0.384–0.561), while compared to never users. For the respective tertiles of cumulative dose, the HRs (95% CIs) were 1.131 (0.962–1.329), 0.739 (0.624–0.876) and 0.525 (0.438–0.629). A risk reduction among ever users was observed for all tertiles of defined daily dose but was most remarkable for the third tertile with a defined daily dose of >0.64. Subgroup analyses suggested that the benefit of metformin could be similarly observed among men and women and for age subgroups of 50–64 and 65–79 years. However, patients with diabetic retinopathy would not be significantly benefited and metformin did not seem to be preventive for exudative AMD. Conclusion: In general, metformin significantly reduces the risk of AMD.