Intravitreal anti-vascular endothelial growth factor treatment and the risk of thromboembolism

Cardiovascular risk in anti-VEGF treatment of neovascular age-related macular degeneration

OBJECTIVE

Assess 5-year all-cause mortality (ACM), hemorrhagic stroke, ischemic stroke, and myocardial infarction (MI) risks in nAMD patients receiving anti-VEGF injections compared with controls.

DESIGN

Population-based retrospective cohort study using a U.S. federated health research network, containing de-identified data of 96 million patients from 1/1/2003 to 3/6/2023.

PARTICIPANTS

nAMD Patients with anti-VEGF injections. Controls included nAMD patients without anti-VEGF injections, non-exudative AMD patients, and patients without AMD.

METHODS

Patients were identified using nAMD ICD-10 and anti-VEGF CPT codes and matched for age, sex, and comorbidities. Five-year relative risk of ACM (RR1), hemorrhagic stroke (RR2), ischemic stroke (RR3), and MI (RR4) in nAMD patients receiving anti-VEGF injections were calculated.

RESULTS

A total of 27,609 nAMD patients (mean diagnosis age [SD], [78.2 (10.3)]) received anti-VEGF injections; 769 nAMD patients without injections (75.8 [12.2]), 27,599 non-exudative AMD patients (78.2 [10.3]), and 21,902 no-AMD patients (76.1 [10.5]) were identified. After matching, nAMD patients receiving injections did not show increased risk versus nAMD patients without injections (RR1, 0.66; 95% CI [0.53, 0.82]), (RR2, 1.00 [0.42, 2.38]), (RR3, 1.70 [0.92,3.13]), (RR4, 0.63 [0.33, 1.18]). No increased risk was found compared to non-exudative AMD patients (RR1, 0.99 [0.95, 1.03]), (RR2, 0.94 [0.83,1.07]), (RR3, 1.04 [0.96, 1.12]), (RR4, 0.99 [0.91, 1.08]). Increased risk for ACM was observed versus no-AMD patients (RR1, 1.21 [1.15, 1.27]), but no other differences were found (RR2, 0.81 [0.70, 0.93]), (RR3, 1.00 [0.92, 1.09]), (RR4, 0.986 [0.90, 1.09]).

CONCLUSION

Anti-VEGF injections were not associated with major cardiovascular events in nAMD patients over 5 years.

The Warburg effect alters amino acid homeostasis in human retinal endothelial cells: implication for proliferative diabetic retinopathy

Proliferative diabetic retinopathy (PDR) remains a leading cause of blindness despite progress in screening and treatment. Recently, the Warburg effect, a metabolic alteration affecting amino acid (AA) metabolism in proliferating cells, has drawn attention regarding its role in PDR. This study aimed to investigate the impact of the Warburg effect on AA metabolism in human retinal endothelial cells (HRECs) subjected to PDR-associated risk factors and validate the findings in patients with PDR. In vitro experiments exposed HRECs to high glucose (HG) and/or hypoxia (Hyp), known inducers of the Warburg effect. The HG + Hyp group of HRECs exhibited significant differences in non-essential AAs with aliphatic non-polar side chains, mainly driven by elevated glycine concentrations. Pathway enrichment analysis revealed several glycine metabolism-related pathways significantly altered due to the Warburg effect induced by HG + Hyp. Crucially, vitreous humor samples from PDR patients displayed higher glycine levels compared to non-diabetic and diabetic patients without PDR. The odds ratio for PDR patients with glycine levels above the cut-off of 0.0836 µM was 28 (p = 0.03) compared to non-PDR controls. In conclusion, this study provides mechanistic insights into how a specific Warburg effect subtype contributes to glycine accumulation in PDR and supports glycine's potential as a biomarker for PDR pathogenesis.

Acetazolamide and bevacizumab combination therapy versus bevacizumab monotherapy in macular edema secondary to retinal vein occlusion

PURPOSE

To determine and compare the efficacy of intravitreal bevacizumab (IVB) and oral acetazolamide (OA) combination therapy versus IVB monotherapy in patients with macular edema secondary to retinal vein occlusion (RVO).

METHODS

This randomized clinical trial included 54 eyes of 52 patients with RVO central macular thickness (CMT) of more than 300μm, and best corrected visual acuity (BCVA) between 20/400 and 20/40. Eligible patients were randomly assigned to two groups: (I) IVB and OA (250mg twice daily) combination therapy or (II) IVB monotherapy. Ocular injections were repeated monthly for up to three months; BCVA and CMT were measured monthly.

RESULTS

Both regimens resulted in significant reduction in CMT (534±150μm to 352±90μm in the IVB+OA group, P<0.001; and 580±175μm to 362±90μm in the IVB group, P<0.001); neither showed superiority in this regard. Likewise, BCVA showed significant improvement in both groups (0.87±0.56 to 0.53±0.28 LogMAR in the IVB+OA group, P=0.001; and 0.85±0.62 to 0.46±0.4 LogMAR in the IVB group, P<0.001), with no intergroup difference.

CONCLUSION

Addition of oral acetazolamide to IVB in eyes with macular edema secondary to RVO may not result in additional short-term benefits regarding functional and anatomical outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT05290948, registered on March 22, 2022. https://clinicaltrials.gov/ct2/show/NCT05290948.

Intravitreal Vascular Endothelial Growth Factor Inhibitor Use and Renal Function Decline in Patients with Diabetic Retinopathy

Adverse renal effects of systemic vascular endothelial growth factor (VEGF) inhibitor treatment are well documented. We aimed to identify associations between intravitreal VEGF inhibitor use and renal function decline in patients with diabetic retinopathy. We included 625 patients with diabetic retinopathy for regular renal function follow-ups and grouped them according to intravitreal therapy (67 with and 558 without treatment). We used a generalized estimating equation model to identify renal function decline risk factors. Increased age (p = 0.02), insulin use (p = 0.01), hypertension (p < 0.01), and ischemic heart disease (p < 0.01) were associated with significantly decreased estimated glomerular filtration rates (eGFRs) in patients with diabetic retinopathy after 1-year follow-up. Compared to the control group, patients who received intravitreal VEGF inhibitor injections showed a declining eGFR trend in the repeated measurement model without statistical significance (p = 0.06). In subgroup analysis, patients with initial eGFR ≤ 30 mL/min/1.73 m² who received intravitreal VEGF inhibitors had significantly decreased renal function (p < 0.01) compared to those without treatment. Intravitreal VEGF inhibitor injection was associated with renal function deterioration among patients with diabetic retinopathy and advanced chronic kidney disease. Strategies to monitor renal function after treatment should be considered in these high-risk populations.

Is perioperative blood pressure monitoring during intravitreal injections important?

Background:

Anti-vascular endothelial growth factor intravitreal injections (IVIs) have proved to be a boon for patients suffering from several retinal pathologies. They are one of the most commonly performed procedures in ophthalmology. A perioperative rise in blood pressure (BP) has been noted during cataract surgery.

Objectives:

To evaluate the perioperative BP changes during IVI, and the associated risk factors.

Design:

Cross-sectional observational study

Methods:

The patients undergoing IVI from May 2019 to August 2019 were evaluated. All the patients underwent BP measurement before, during, and 1 h after the IVI. The correlation between the demographics and, the systemic comorbidities of the patients, and the ocular condition for which IVI was given was evaluated.

Results:

The study included 302 patients (mean age of 59.9 ± 10.7 years). The mean increase in systolic BP (SBP) and diastolic BP (DBP) at the time of injection was 25.7 ± 21.0 and 1.3 ± 13.4 mmHg, respectively. A ⩾ 10, ⩾ 20, ⩾ 30 mmHg increase in SBP at the time of injection was seen in 83.8% (n = 253), 69.5% (n = 210) and 49.0% (n = 148) patients, respectively. Forty-one (13.6%) patients developed intra-procedural hypertensive urgency, out of which six patients (14.6%) did not recover even after 1 h of the procedure. None of the patients experienced any cardiovascular events. The univariate and multivariate linear regression analyses showed that the change in intra-procedural SBP correlated positively with the age of the patient and negatively with the baseline SBP.

Conclusion:

There is a significant rise of SBP at the time of IVI, especially in patients with advanced age and high baseline SBP. Some of the patients can experience hypertensive urgency at the time of injection and may take more than 1 h to recover. The patients receiving IVI should undergo a detailed physician evaluation before the procedure.

Risk of Myocardial Infarction, Stroke, or Death in New Users of Intravitreal Aflibercept Versus Ranibizumab: A Nationwide Cohort Study

Introduction

The risk of thromboembolic events or death in patients treated with intravitreal anti-vascular endothelial growth factor (IVT anti-VEGF) is poorly described on a large scale and by molecule. This study aimed to assess the risk of myocardial infarction (MI), stroke, or death in new users of IVT aflibercept versus ranibizumab in real-world practice.

Methods

A nationwide cohort study using the French National Health Insurance databases covering 99% of the French population was conducted in patients aged 18 years or older who initiated IVT therapy with ranibizumab or aflibercept between 2014 and 2018. Patients were followed for up to 6 years until December 31, 2019. The risks of MI, stroke, and death were compared in new aflibercept versus ranibizumab users using Kaplan–Meier and multivariate Cox proportional hazards models adjusted on sociodemographic characteristics and cardiovascular disease or risk factors. Subgroup analyses were performed according to history of ischemic heart disease or stroke, diabetes, indication for treatment, sex, age, and number of IVT anti-VEGF injections.

Results

When compared to new users of ranibizumab (n = 174,794, mean age 76.0 ± 11.9 years, 59.2% female), new users of aflibercept (n = 76,242, mean age 76.6 ± 11.2 years, 59.2% female) did not have an increased risk of MI (n = 1523 incident MI, adjusted hazard ratio [aHR] 1.00; 95% CI 0.89–1.11), stroke (n = 2306 incident strokes, aHR 1.03; 95% CI 0.95–1.13), or death (n = 4135 deaths, aHR 0.98; 95% CI 0.92–1.05). However, a small but non-statistically significant increase in the risk of stroke was observed in new users of aflibercept versus ranibizumab among patients with diabetes (aHR 1.15; 95% CI 0.98–1.35), particularly those with diabetic macular edema (aHR 1.20; 95% CI 1.00–1.44). The remaining subgroup analyses did not change the results.

Conclusion

Aflibercept and ranibizumab appear to have similar safety profiles with respect to the risk of MI, stroke, or death under real-world conditions of use.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40123-021-00451-1.

Increased mortality after intravitreal injections of anti-VEGF for neovascular AMD among patients with prior stroke or acute myocardial infarction

OBJECTIVES

To evaluate whether intravitreal injections (IVI) of anti-vascular endothelial growth factor (anti-VEGF) in neovascular age-related macular degeneration (nAMD) patients with prior stroke or acute myocardial infarction (AMI) are associated with increased mortality.

METHODS

From 2005 to 2013, nAMD patients in the Taiwan National Health Insurance Research Database who received IVI of anti-VEGF and had a diagnosis of stroke/AMI prior to their first injections were defined as the IVI group. The mortality of the IVI group during the study period was compared to that of the non-IVI group, which consisted of nAMD patients who had prior stroke/AMI but were never exposed to anti-VEGF. The IVI group and the non-IVI group were 1-4 matched according to propensity score (PS), which was derived from age, sex, date of stroke/AMI and comorbidities. PS-adjusted Cox regression analyses were used to estimate the hazard ratio (HR) for mortality associated with IVI of anti-VEGF. Subgroup analyses were also performed according to the interval between stroke/AMI and IVI (≤6 months, 6 months to 1 year, 1-2 years, >2 years).

RESULTS

There were 3384 individuals in the IVI group and 13,536 individuals in the non-IVI group. The IVI group had a significantly higher mortality risk (adjusted HR = 2.37; 95% confidence interval (CI), 2.14-2.62) than the non-IVI group. Subgroup analyses revealed that elevated mortality was significant when anti-VEGF was injected within 1 year after stroke/AMI.

CONCLUSIONS

We found an increased mortality risk associated with IVI of anti-VEGF in nAMD patients with prior stroke/AMI compared to the mortality risk of nAMD patients with prior stroke/AMD but without exposure to anti-VEGF.

Inhibition of APE1/Ref-1 for Neovascular Eye Diseases: From Biology to Therapy

Proliferative diabetic retinopathy (PDR), neovascular age-related macular degeneration (nvAMD), retinopathy of prematurity (ROP) and other eye diseases are characterized by retinal and/or choroidal neovascularization, ultimately causing vision loss in millions of people worldwide. nvAMD and PDR are associated with aging and the number of those affected is expected to increase as the global median age and life expectancy continue to rise. With this increase in prevalence, the development of novel, orally bioavailable therapies for neovascular eye diseases that target multiple pathways is critical, since current anti-vascular endothelial growth factor (VEGF) treatments, delivered by intravitreal injection, are accompanied with tachyphylaxis, a high treatment burden and risk of complications. One potential target is apurinic/apyrimidinic endonuclease 1/reduction-oxidation factor 1 (APE1/Ref-1). The multifunctional protein APE1/Ref-1 may be targeted via inhibitors of its redox-regulating transcription factor activation activity to modulate angiogenesis, inflammation, oxidative stress response and cell cycle in neovascular eye disease; these inhibitors also have neuroprotective effects in other tissues. An APE1/Ref-1 small molecule inhibitor is already in clinical trials for cancer, PDR and diabetic macular edema. Efforts to develop further inhibitors are underway. APE1/Ref-1 is a novel candidate for therapeutically targeting neovascular eye diseases and alleviating the burden associated with anti-VEGF intravitreal injections.

Cardiovascular risk in patients receiving ranibizumab for exudative age-related macular degeneration: a nationwide self-controlled case-series study

AIMS

To identify the association between ranibizumab and risk of stroke and acute myocardial infarction (AMI) in patients with exudative age-related macular degeneration (AMD).

METHODS

We identified patients aged ≥45 years who received ranibizumab for exudative AMD from the Korean National Health Insurance database. Of these, we selected patients suffering stroke or AMI for the self-controlled case series. We estimated incidence rate ratios (IRR) for stroke or AMI by comparing incidence rates of ranibizumab-exposed periods to that of baseline using conditional Poisson regression. The risks of haemorrhagic and ischaemic strokes were also calculated separately.

RESULTS

Among 33 134 patients receiving ranibizumab, 2397 patients had stroke or AMI. The risk of stroke (IRR=0.83, 95% CI 0.75 to 0.91) was not increased during the overall exposed period; however, there was a marginally elevated risk in ≥57 days exposed period (IRR=1.14, 95% CI 1.001 to 1.31). When analysing by the types of stroke, no increased risks of haemorrhagic (IRR=1.01, 95% CI 0.80 to 1.26) and ischaemic stroke (IRR=0.78, 95% CI 0.71 to 0.86) were observed during the exposed period, although the risks of ischaemic and haemorrhagic stroke were slightly elevated during ≥57 days exposed period. We could not find an association between ranibizumab and AMI.

CONCLUSIONS

Ranibizumab intravitreal injections did not increase the overall risk of stroke or AMI. Although the cardiovascular risk in patient receiving ranibizumab seems to be low, continuous monthly use of ranibizumab for high-risk patients should be judged carefully.

Association between Ranibizumab Injections and Risk of Acute Myocardial Infarction in Age-related Macular Degeneration: A Case-crossover Study

PURPOSE

This study aimed to evaluate the risk of acute myocardial infarction (AMI) associated with intravitreal ranibizumab in age-related macular degeneration (AMD).

METHODS

This nationwide retrospective case-crossover study using data from the Korean National Health Insurance Service database included patients diagnosed with exudative AMD using the registration code for exudative AMD (V201) from 2009 to 2014. We identified all incident AMI cases among these exudative AMD cases from inpatient claims and defined the index date as the date of hospitalization. For each patient, we defined the case period as one to 60 days and four control periods as 121 to 180, 181 to 240, 241 to 300, and 301 to 361 days, respectively, before the index date. A prescription of ranibizumab was searched for during the case and control periods. We calculated the adjusted odds ratios and their 95% confidence intervals using a conditional logistic regression model.

RESULTS

From a cohort of patients with exudative AMD (n = 41,860), a total of 181 AMI patients with exudative AMD were included. Among all the patients, 11.05% were treated during the 2 months preceding the index date as compared with 8.29% to 9.39% treated during control periods. The adjusted odds ratio of AMI associated with intravitreal ranibizumab during the preceding 2 months was 1.22 (95% confidence interval, 0.673-2.213; p = 0.5124). Analyses based on case periods of 15 days and 1 month yielded similar results.

CONCLUSIONS

Intravitreal ranibizumab injection does not appear to increase the risk of hospitalization for AMI within 60 days in exudative AMD patients.

Association of Intravitreal Anti-Vascular Endothelial Growth Factor Therapy With Risk of Stroke, Myocardial Infarction, and Death in Patients With Exudative Age-Related Macular Degeneration

Importance

Current studies assessing the risk of stroke, myocardial infarction (MI), and death in patients undergoing intravitreal anti-vascular endothelial growth factor (VEGF) therapy are inconclusive. To our knowledge, no population-based studies have been performed to examine these potential risks.

Objective

To examine whether patients with exudative age-related macular degeneration (AMD) receiving intravitreal anti-VEGF injections have a higher incidence of MI, stroke, or death compared with control populations.

Design, Setting, and Participants

This population-based, retrospective cohort study included 504 patients from Olmsted County, Minnesota, identified through the Rochester Epidemiology Project (REP) database as receiving at least 1 intravitreal anti-VEGF injection for exudative AMD from January 1, 2004, to December 31, 2013. Three age- and sex-matched control groups of individuals who did not receive anti-VEGF treatment and were derived from the REP database were also studied: control individuals with exudative AMD in the era before anti-VEGF (January 1, 1990, to December 31, 2003), controls with dry AMD, and controls without AMD. Data analysis was performed from September 1, 2016, to September 1, 2017.

Main Outcomes and Measures

Five-year risk of stroke, MI, and death were assessed in patients compared with controls using Kaplan-Meier and multivariate analysis with Cox proportional hazards regression models.

Results

The study included 504 patients (321 female [63.7%]; mean [SD] age, 76.5 [10.0] years) who received at least 1 intravitreal anti-VEGF injection for exudative AMD during the study period. Kaplan-Meier analysis revealed a 5-year risk of 7.2% for stroke, 6.1% for MI, and 30.0% for death. Patients who received anti-VEGF had no increased risk of stroke or MI compared with controls with dry AMD (n = 504), controls with exudative AMD (n = 473), or controls without AMD (n = 504). There was an increased risk of mortality compared with controls with exudative AMD in the era prior to anti-VEGF therapy but not the other control groups on multivariate analysis (hazard ratio, 1.63; 95% CI, 1.30-2.04; P < .001).

Conclusions and Relevance

This population-based study revealed that intravitreal anti-VEGF therapy for exudative AMD was not associated with consistent increases in the risk of stroke, MI, or death compared with no therapy in patients with or without AMD. It appears to be likely the cardiac events these patients experience are not attributable to their anti-VEGF therapy.

Classification of Strokes in Patients Receiving Intravitreal Anti-Vascular Endothelial Growth Factor

BACKGROUND AND OBJECTIVE

The purpose of this study was to identify the differences in the types of strokes seen in patients receiving intravitreal anti-vascular endothelial growth factor (VEGF) compared with normal control populations.

PATIENTS AND METHODS

We performed a retrospective consecutive review of all patients receiving intravitreal anti-VEGF injections in Olmsted County, Minnesota, from January 1, 2004, to December 31, 2013, for exudative age-related macular degeneration (AMD), diabetic macular edema (DME), proliferative diabetic retinopathy (PDR), or retinal vein occlusion (RVO). A 2-year follow-up period was required for study inclusion. Three age- and sex-matched cohorts were identified.

RESULTS

A total of 2,541 patients were examined. There were 690 patients identified during the study period as receiving an intravitreal injection for AMD, DME, PDR, or RVO. Of these patients, 38 (5.8%) suffered a stroke after starting intravitreal injection therapy. Of these strokes, 27 (71.1%) were ischemic, six (15.8%) were embolic, and five (13.2%) were hemorrhagic. There were no differences in the types of strokes identified among the patients receiving intravitreal injections between the case cohort and the control cohorts (P > .05 for all).

CONCLUSION

The authors' data suggest there is no predilection to the development of ischemic infarcts or hemorrhagic strokes in those patients receiving intravitreal anti-VEGF compared with control populations. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:e140-e157.].

Association of Age-Related Macular Degeneration With Risk of All-Cause and Specific-Cause Mortality in the National Health and Nutrition Examination Survey, 2005 to 2008

Question

What is the association of age-related macular degeneration with mortality outcomes among older adults?

Findings

In this cohort study of 5603 participants 40 years or older, only late age-related macular degeneration was associated with more than a doubling of all-cause mortality and more than 3-fold higher risk of mortality not due to cardiovascular disease and cancer.

Meaning

The association of late age-related macular degeneration and poor survival may shed light on mechanisms underlying the disease, indicating that late age-related macular degeneration may be a marker of frailty and aging or may be due to residual confounding factors indicative of aging.

Importance

Age-related macular degeneration (AMD) is the leading cause of irreversible visual impairment and blindness in the United States if subretinal neovascularization is left untreated. Knowledge of the association between AMD and survival is informative for underlying mechanisms of AMD.

Objective

To examine the association between AMD and risk of all-cause and specific-cause mortality in a representative US sample.

Design, Setting, and Participants

This population-based prospective cohort study included 5603 participants 40 years or older who responded to the National Health and Nutrition Examination Survey (NHANES) in the 2005-2008 phase. Retinal photographs were graded as early, late, or no AMD. All analyses accounted for the complex and stratified design of NHANES with weighted data. Risks of all-cause mortality were assessed with Cox proportional hazards regression models; risks of specific-cause mortality, with Fine and Gray competing risks regression models. Time to death was counted from baseline to date of death or December 31, 2011, whichever came first. Data analysis was conducted from April 1 through 30, 2018.

Exposures

Age-related macular degeneration status as determined by digital fundus images.

Main Outcomes and Measures

Mortality resulting from all causes and specific causes until December 31, 2011.

Results

Among the 5603 participants (52.6% female [n = 2793] and 77.1% white [n = 3017]; mean [SE] age, 56.4 [0.4] years), weighted prevalence of any AMD was 6.6%, with 386 (5.8%) having early AMD and 55 (0.8%) having late AMD. After a median follow-up of 4.5 years (interquartile range, 3.6-5.6 years), 433 (5.3%) died of all causes, of whom 361 (83.1%) had no AMD, 54 (11.5%) had signs of early AMD, 18 (5.4%) had signs of late AMD, and 72 (16.9%) had any AMD at baseline. Overall, unadjusted all-cause and specific-cause mortality rates were higher for those participants who had early, late, or any AMD compared with no AMD. However, after adjusting confounding factors, only late AMD was associated with more than a doubling of all-cause mortality (hazard ratio [HR], 2.01; 95% CI, 1.00-4.03) and more than a 3-fold higher risk of mortality due to causes other than cardiovascular disease and cancer (HR, 3.42; 95% CI, 1.38-8.49). No association was identified between AMD presence or early AMD and all-cause or specific-cause mortality.

Conclusions and Relevance

In this study’s findings, only late AMD was independently associated with all-cause mortality and mortality due to causes other than cardiovascular disease and cancer, indicating that late AMD may be a marker of biological aging. Alternatively, this association may be due to unmeasured or inadequately assessed confounding factors for late AMD.

Expression of vascular infarction-related molecules after anti-vascular endothelium growth factor treatment for diabetic macular edema

To determine whether an intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF) in eyes with diabetic macular edema (DME) affects the vascular infarction-related molecules (VIRMs). Nineteen eyes with DME were treated with 0.5 mg of intravitreal ranibizumab (IVR), and 22 eyes with DME were treated with 2 mg of intravitreal aflibercept (IVA). Blood was collected before, 1 week and 1 month after the injections. Aqueous humor was collected before and 1 month after the injections. The concentration of the VIRMs (cardiac myoglobin, cardiac troponin, intercellular adhesion molecule, monocyte chemotactic protein-1, matrix metalloproteinase-8, placental growth factor [PlGF], tenascin-C, tissue inhibitor of metalloproteinase-1, thrombospondin-2, vascular cell adhesion molecule-1, and VEGF) were determined by the multiplex assay. After the single injection of both types of anti-VEGF agents, the concentration of aqueous VEGF decreased significantly (P < 0.01). The plasma VEGF was reduced significantly at 1 week after the IVA (93.7 ± 17.6 to 39.5 ± 11.6 pg/ml; P < 0.01) but no significant change was seen after IVR (120.2 ± 11.3 to 137.4 ± 17.7 pg/ml). No significant changes were detected for the other VIRMs in the plasma and aqueous. A single intravitreal injection of anti-VEGF for DME does not significantly affect the concentration of several VIRMs.

Vitrectomy for macular edema due to retinal vein occlusion

Purpose: To determine the long-term outcomes of vitrectomy for the macular edema associated with a retinal vein occlusion (RVO).

Methods: This was a retrospective, consecutive, interventional case series. The intraoperative procedures included internal limiting membrane peeling, arteriovenous sheathotomy, radial optic neurotomy, and intravitreal triamcinolone acetonide injection at the end of the surgery. The main outcome was the best-corrected visual acuity (BCVA).

Results: Eight hundred and fifty-four eyes of 854 patients were studied. The eyes consisted of 602 with branch RVO (BRVO), 74 with hemi-central RVO (hemi-CRVO), 87 with nonischemic central retinal vein occlusion (CRVO), and 91 with ischemic CRVO. The mean follow-up period was 68.6 months with a range of 12 to 262 months. The mean BCVA was significantly improved at the final visit (P<0.0001 to 0.0016). The final BCVA improved in 74.4% of the BRVO eyes, in 58.1% of the hemi-CRVO eyes, in 57.4% of the nonischemic CRVO eyes, and in 51.6% of the ischemic CRVO eyes. Multiple regression analysis showed there was no significant relationship between the intraoperative combined procedures and the final BCVA.

Conclusions: The results indicate that the type of RVO is significantly associated with the final BCVA, and vitrectomy is a treatment option to improve and maintain BCVA for a long term.

Effectiveness of prophylactic intravitreal bevacizumab injection to proliferative diabetic retinopathy patients with elevated preoperative intraocular VEGF in preventing complications after vitrectomy

Purpose

This study aimed to elucidate the effects of intravitreal bevacizumab (IVB) injections for the prevention of post-vitrectomy complications in proliferative diabetic retinopathy (PDR) patients with elevated vitreous vascular endothelial growth factor (VEGF) concentration.

Design

Prospective case series.

Methods

Thirty-three patients (42 eyes) with PDR who underwent primary vitrectomy in the Department of Ophthalmology, Tokyo Medical University Hospital were studied. We measured VEGF concentrations in vitreous humor collected at the time of vitrectomy using ELISA. IVB injections were performed after vitrectomy in patients with vitreous VEGF levels exceeding 1,000 pg/mL. New bleeding occurring within 1 month of vitrectomy was defined as early vitreous hemorrhage (VH).

Main outcome measure

The incidence of complications after vitrectomy including postoperative early VH.

Results

IVB injections were administered to 11 eyes (26%) with vitreous VEGF concentrations exceeding 1,000 pg/mL. None of the 11 eyes that received an IVB injection developed early VH. Among 31 eyes (74%) with vitreous VEGF concentrations lower than 1,000 pg/mL, two eyes (6%) developed early VH after vitrectomy.

Conclusions

Prophylactic IVB injections administered to patients with elevated preoperative intraocular VEGF concentrations were effective in preventing post-vitrectomy early VH.

Intravitreal bevacizumab treatment for neovascular age-related macular degeneration and thromboembolic events

BACKGROUND

Systemic complications of intravitreal anti-vascular endothelial growth factor agents are relatively uncommon but highly significant.

OBJECTIVES

Primary objective: To assess the risk for thromboembolic events following intravitreal bevacizumab injection in neovascular age-related macular degeneration patients by a large population-based study. Secondary objective: To analyze the association between injection frequency and the risk for thromboembolic events, the time interval between the injection and the thromboembolic events, and the influence of chronic diseases on complications rate.

DESIGN

A retrospective cohort study.

METHODS

Consecutive neovascular age-related macular degeneration patients receiving intravitreal bevacizumab at Soroka University Medical Center from December 2005 to December 2013 were included. Thromboembolic events analyzed included acute coronary syndrome, acute myocardial infarction, stroke, deep vein thrombosis, and pulmonary embolism. The thromboembolic event rate was compared 2 years prior and 2 years after the initial intravitreal bevacizumab injection.

RESULTS

A total of 2102 patients were included. Acute coronary syndrome and stroke rate were higher 2 years after intravitreal bevacizumab (p = 0.03 and p = 0.01, respectively). No statistical significant difference was found for the rest of thromboembolic events. Patients older than 80 years and patients receiving less than six intravitreal bevacizumab injections were more likely to experience stroke. Patients with known cardiovascular risk factors before starting injections did not develop significant more thromboembolic events.

CONCLUSION

In our study population, patients treated with intravitreal bevacizumab were significantly more likely to experience stroke during 2 years after first injection.

CHANGES IN PLASMA VASCULAR ENDOTHELIAL GROWTH FACTOR LEVEL AFTER INTRAVITREAL INJECTION OF BEVACIZUMAB, AFLIBERCEPT, OR RANIBIZUMAB FOR DIABETIC MACULAR EDEMA

PURPOSE

The aim of this study was to investigate the changes in plasma vascular endothelial growth factor (VEGF) level depending on the severity of diabetic retinopathy (DR) or diabetic macular edema (DME) and after intravitreal injection of bevacizumab, aflibercept, or ranibizumab for treatment of DME.

METHODS

Plasma VEGF level was evaluated in 72 patients with DR and changes were measured in 42 patients with DME receiving intravitreal injections of bevacizumab, aflibercept, or ranibizumab at the initial injection.

RESULTS

There were no correlations between plasma VEGF level and the severity of DME or DR. Baseline plasma VEGF level (51.9 pg/mL) was significantly reduced using bevacizumab to 11.9 pg/mL after 1 week and 24.1 pg/mL after 4 weeks (P = 0.0130 and 0.0201, respectively). In aflibercept-treated eyes, plasma VEGF decreased from 52.2 pg/mL to 7.8 pg/mL and 12.6 pg/mL, respectively, at the same time points (both P < 0.001). No such reductions were observed in patients receiving ranibizumab.

CONCLUSION

Baseline plasma VEGF level showed no correlations with DR or DME severity, whereas intravitreal injection of bevacizumab or aflibercept significantly reduced plasma VEGF for up to 4 weeks and ranibizumab produced no such effects. Changes in plasma VEGF level seemed not to be critical in progression or treatment of DME and DR.

Association of Cataract Surgery With Traffic Crashes

Importance

Cataracts are the most common cause of impaired vision worldwide and may increase a driver's risk of a serious traffic crash. The potential benefits of cataract surgery for reducing a patient's subsequent risk of traffic crash are uncertain.

Objective

To conduct a comprehensive longitudinal analysis testing whether cataract surgery is associated with a reduction in serious traffic crashes where the patient was the driver.

Design, Setting, and Participants

Population-based individual-patient self-matching exposure-crossover design in Ontario, Canada, between April 1, 2006, and March 31, 2016. Consecutive patients 65 years and older undergoing cataract surgery (n = 559 546).

Interventions

First eye cataract extraction surgery (most patients received second eye soon after).

Main Outcomes and Measures

Emergency department visit for a traffic crash as a driver.

Results

Of the 559 546 patients, mean (SD) age was 76 (6) years, 58% were women (n = 326 065), and 86% lived in a city (n = 481 847). A total of 4680 traffic crashes (2.36 per 1000 patient-years) accrued during the 3.5-year baseline interval and 1200 traffic crashes (2.14 per 1000 patient-years) during the 1-year subsequent interval, representing 0.22 fewer crashes per 1000 patient-years following cataract surgery (odds ratio [OR], 0.91; 95% CI, 0.84-0.97; P = .004). The relative reduction included patients with diverse characteristics. No significant reduction was observed in other outcomes, such as traffic crashes where the patient was a passenger (OR, 1.03; 95% CI, 0.96-1.12) or pedestrian (OR, 1.02; 95% CI, 0.88-1.17), nor in other unrelated serious medical emergencies. Patients with younger age (OR, 1.27; 95% CI, 1.13-1.14), male sex (OR, 1.64; 95% CI, 1.46-1.85), a history of crash (baseline OR, 2.79; 95% CI, 1.94-4.02; induction OR, 4.26; 95% CI, 2.01-9.03), more emergency visits (OR, 1.34; 95% CI, 1.19-1.52), and frequent outpatient physician visits (OR, 1.17; 95% CI, 1.01-1.36) had higher risk of subsequent traffic crashes (multivariable model).

Conclusions and Relevance

This study suggests that cataract surgery is associated with a modest decrease in a patient's subsequent risk of a serious traffic crash as a driver, which has potential implications for mortality, morbidity, and costs to society.

[Embolic stroke immediately after initial administration of intravitreal aflibercept]

A 72-year-old man was admitted to our hospital because of right upper limb monoplegia 8 hours after the initial intravitreal injection of aflibercept, which is an inhibitor of vascular endothelial growth factor. Magnetic resonance diffusion-weighted images showed recent ischemic lesions in the left corona radiata and the right superior frontal gyrus. Laboratory findings showed mild hyperfibrinolysis. A patent foramen ovale was diagnosed on transesophageal echocardiography; however, lower-extremity ultrasonography did not detect deep vein thrombosis. The source of embolism remained unknown. A possible mechanism of cerebral emboli in the present case was a rapidly induced hypercoagulative state due to transfer of aflibercept from the vitreous body to the systemic circulation.

Ranibizumab and digital ischemia

Case report of a patient with age-related macular degeneration whose digital ischemia can most plausibly be attributed to ranibizumab.

PURPOSE

To report ranibizumab as the probable cause of digital ischemia in a patient treated for age-related macular degeneration.

METHODS

Single-patient case report.

RESULTS

An 83-year-old woman with an unremarkable medical history suffered acute ischemia in her left hand with necrosis of the distal phalange of the fifth finger after six intravitreal injections of ranibizumab. Her etiological work-up was negative. Her condition improved after endovascular revascularization and remained good at six months' follow-up after three months of dual antithrombotic therapy (low molecular weight heparin then rivaroxaban, both with aspirin) followed by rivaroxaban alone and four courses of intravenous iloprost.

CONCLUSION

The increased incidence of peripheral arterial thromboembolic events in patients under ranibizumab treatment is slight but significant, with 0.8-5% of patients affected, most of which suffer strokes. These events seem to occur at a random time after ranibizumab treatment is initiated and no reliable marker has yet been identified. The most probable cause of digital ischemia in our patient was ranibizumab.

Effect of oral tranexamic acid on macular edema associated with retinal vein occlusion or diabetes

Purpose

Tranexamic acid (TXA) is a widely used antifibrinolytic agent that can also cause a decrease in vascular permeability. We hypothesized that TXA could improve macular edema (ME) that is caused by an increase in retinal vascular permeability. The aim of this study is to evaluate the efficacy of oral TXA for ME associated with retinal vein occlusion (RVO) or diabetic ME (DME).

Patients and methods

Oral TXA (1,500 mg daily for 2 weeks) was administered to patients with persistent ME secondary to RVO (7 eyes) and DME (7 eyes). After 2 weeks (ie, the final day of administration) and 6 weeks (ie, 4 weeks after the final administration), best-corrected visual acuity and central macular thickness (CMT) were measured and compared with baseline. Analyses were performed for RVO and DME cases. No other treatment was performed during the study period.

Results

In RVO cases, significant improvement in CMT was found between baseline (467.7±121.4 μm) and 2-week measurements after treatment (428.7±110.5 μm, p=0.024). No significant change was found in CMT between measurements taken at baseline and 6 weeks after treatment. In DME cases, no significant change was found in CMT between measurements taken at baseline and 2 or 6 weeks after treatment. In all analyses of best-corrected visual acuity, no significant change was observed.

Conclusion

The results support the hypothesis that plasmin plays a role in the development of ME associated with RVO, and oral TXA administration may be useful as an adjuvant treatment when combined with other agents such as anti-vascular endothelial growth factor.

Effect of intravitreal ranibizumab on the ocular circulation of the untreated fellow eye

Purpose

To evaluate the effects of unilateral intravitreal ranibizumab (IVR) on the ocular circulation of the fellow eyes.

Methods

Fifteen eyes of 15 patients with macular edema (average age 69.6 ± 11.8 years) were studied. Eleven eyes had diabetic macular edema (DME) and four eyes had macular edema associated with a branch retinal vein occlusion. Each eye received 0.5 mg of IVR. The blood circulation on the optic nerve head of the treated and untreated eyes were determined by laser speckle flowgraphy (LSFG, Softcare Co., Ltd) before, 1 day, and 1 week after the IVR. The mean blur rate (MBR) and the relative changes of the MBRs determined as dMBR(%) = 100−(MBR before/MB after) × 100) were evaluated. The central macular thickness (CMT) and the rate of reduction in the thickness (dCMT = 100−(CMT before/CMT after) × 100) were also evaluated.

Results

The mean dMBR was significantly higher in the treated eyes than the untreated eyes at 1 day (−16.4 ± 17.0% vs 2.31 ± 19.3%) and at 1 week (−12.0 ± 14.6% vs 4.50 ± 25.9%) after the IVR (P = 0.02, paired t tests).

Conclusion

These findings indicate that if ranibizumab enters the systemic circulation, the concentration is not high enough to affect the ocular circulation of the fellow eyes.

A safety study of high concentration and high frequency intravitreal injection of conbercept in rabbits

The novel anti-VEGF drug conbercept has been used in the treatment of several retinal neovascular diseases. Owning to the alteration of the structure, the newest drug is capable of combining more molecular targets and present higher affinity to the angiogenesis promoting factors. However, it is unknown whether it will cause any unwanted effects like other anti-VEGF agents. We studied the short-term safety of high concentration and high frequency intravitreal injection of conbercept in rabbits. Intraocular pressure, fundus-photography, ERGs were applied. Retinal morphology, the amount of apoptotic cells and protein levels of IL-6, IL-8 and TNF-α in the aqueous humor were determined. Retinal proteomics was detected using tandem mass tags (TMTs) quantitative mass spectrometry. The difference of IOP, ERGs, protein levels of inflammatory factors among rabbits received conbercept and PBS was not significant (P > 0.05). Fundus photographs and retinal morphology of animals in the conbercept-injected groups mimic those observed in the PBS-injected groups. No TUNEL-positive cell was seen in the retinal ganglion cell layer in the conbercept-injected groups. Proteomics did not show significant changes of inflammation or apoptosis associated proteins in the conbercept-injected eyes. We conclude that intravitreal injection of high concentration and high frequency conbercept is well tolerated at least in a short-term in rabbits.

Introducing Anti-Vascular Endothelial Growth Factor Therapies for AMD Did Not Raise Risk of Myocardial Infarction, Stroke, and Death

PURPOSE

To assess the effect of availability of anti-vascular endothelial growth factor (VEGF) therapy on mortality and hospitalizations for acute myocardial infarction (AMI) and stroke over a 5-year follow-up period in United States Medicare beneficiaries newly diagnosed with exudative age-related macular degeneration (AMD) in 2006 compared with control groups consisting of beneficiaries (1) newly diagnosed with exudative AMD at a time when anti-VEGF therapy was not possible and (2) newly diagnosed with nonexudative AMD.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Beneficiaries newly diagnosed with exudative and nonexudative AMD in 2000 and 2006 selected from a random longitudinal sample of Medicare 5% claims and enrollment files.

METHODS

Beneficiaries with a first diagnosis of exudative AMD in 2006 were the treatment group; beneficiaries newly diagnosed with exudative AMD in 2000 or nonexudative AMD in 2000 or 2006 were control groups. To deal with potential selection bias, we designed an intent-to-treat study, which controlled for nonadherence to prescribed regimens. The treatment group consisted of patients with clinically appropriate characteristics to receive anti-VEGF injections given that the therapy is available, bypassing the need to monitor whether treatment was actually received. Control groups consisted of patients with clinically appropriate characteristics but first diagnosed at a time when the therapy was unavailable (2000) and similar patients but for whom the therapy was not clinically indicated (2000, 2006). We used a Cox proportional hazard model.

MAIN OUTCOME MEASURES

All-cause mortality and hospitalization for AMI and stroke during follow-up.

RESULTS

No statistically significant changes in probabilities of death and hospitalizations for AMI and stroke within a 5-year follow-up period were identified in exudative AMD beneficiaries newly diagnosed in 2006, the beginning of widespread anti-VEGF use, compared with 2000. As an alternative to our main analysis, which excluded beneficiaries from nonexudative AMD group who received anti-VEGF therapies during follow-up, we performed a sensitivity analysis with this group of individuals reincluded (11% of beneficiaries newly diagnosed with nonexudative AMD in 2006). Results were similar.

CONCLUSIONS

Introduction of anti-VEGF agents in 2006 for treating exudative AMD has not posed a threat of increased risk of AMI, stroke, or all-cause mortality.

miRNA involvement in angiogenesis in age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly. Late-stage AMD is characterized by choroidal neovascularization (CNV). miR-93 appears to play a role in regulating vascular endothelial growth factor-A (VEGF-A), a known factor involved in neovascularization. Understanding its biological significance might enable development of therapeutic interventions for diseases like AMD. We aimed to determine the role of miR-93 in AMD using a laser-induced CNV mouse model. CNV was induced by laser photocoagulation in C57BL/6 mice. The CNV mice were transfected with scrambled miR or miR-93 mimic. The treatment effect was assessed by fundus photography and fluorescein angiography and confirmed by choroidal flatmount. The expression of miR-93 and VEGF-A in ocular tissues was analysed by quantitative polymerase chain reaction (qPCR) and Western blot. The overexpression effects of miR-93 were also proved on human microvascular endothelial cells (HMECs). Significantly decreased expression of miR-93 was observed by qPCR analysis in CNV mice compared to untreated mice (p < 0.05). VEGF-A messenger RNA (mRNA) and protein expression were upregulated with CNV; these changes were ameliorated by restoration of miR-93 (p < 0.05). CNV was reduced after miR-93 transfection. Transfection of miR-93 reduced the proliferation of HMECs (p < 0.01), but no significant changes were observed in 2D capillary-like tube formation (p > 0.05) and migration (p > 0.05) compared with that in the untreated cells. miR-93 has been shown to be a negative modulator of angiogenesis in the eye. All together, these results highlight the therapeutic potential of miR-93 and suggest that it may contribute as a putative therapeutic target for AMD in humans.

miR-126 Regulation of Angiogenesis in Age-Related Macular Degeneration in CNV Mouse Model

miR-126 has recently been implicated in modulating angiogenic factors in vascular development. Understandings its biological significance might enable development of therapeutic interventions for diseases like age-related macular degeneration (AMD). We aimed to determine the role of miR-126 in AMD using a laser-induced choroidal neovascularization (CNV) mouse model. CNV was induced by laser photocoagulation in C57BL/6 mice. The CNV mice were transfected with scrambled miR or miR-126 mimic. The expression of miR-126, vascular endothelial growth factor-A (VEGF-A), Kinase insert domain receptor (KDR) and Sprouty-related EVH1 domain-containing protein 1 (SPRED-1) in ocular tissues were analyzed by qPCR and Western blot. The overexpression effects of miR-126 were also proven on human microvascular endothelial cells (HMECs). miR-126 showed a significant decrease in CNV mice (p < 0.05). Both mRNA and protein levels of VEGF-A, KDR and SPRED-1 were upregulated with CNV; these changes were ameliorated by restoration of miR-126 (p < 0.05). CNV was reduced after miR-126 transfection. Transfection of miR-126 reduced the HMECs 2D-capillary-like tube formation (p < 0.01) and migration (p < 0.01). miR-126 has been shown to be a negative modulator of angiogenesis in the eye. All together these results high lights the therapeutic potential of miR-126 suggests that it may contribute as a putative therapeutic target for AMD in humans.

A Review of Randomized Trials of Approved Pharmaceutical Agents for Macular Edema Secondary to Retinal Vein Occlusion

There are 3 approved pharmaceutical agents for treating macular edema secondary to retinal vein occlusion (RVO): dexamethasone (a corticosteroid) implant and ranibizumab and aflibercept (both antivascular endothelial growth factor agents). All show a superior ability to improve vision and reduce macular thickness in comparison with sham injections or macular grid laser treatment. Prompt treatment with these agents may lead to a better outcome. A review of randomized trials of injected aflibercept or ranibizumab reveals protocol variations. They include "as needed" injections until functional and anatomical changes are achieved, preceded by either 1 injection or 3 to 6 monthly injections as loading doses. Ocular and systemic adverse effects of vascular endothelial growth factor antagonists for macular edema secondary to RVO are rarely severe. The antiedematous response to a single intravitreal dexamethasone implant is maximal 1 to 3 months after the injection. Intraocular pressure elevation and cataract aggravation should be monitored after the use of intravitreal dexamethasone implants. Intravitreal dexamethasone implants and ranibizumab injections reduce not only macular edema, but also the risk of retinal ischemia and neovascularization in patients with RVO.

Risk of Myocardial Infarction and Stroke With Single or Repeated Doses of Intravitreal Bevacizumab in Age-Related Macular Degeneration

PURPOSE

To examine the risk of myocardial infarction and stroke with single and repeated doses of intravitreal bevacizumab in wet age-related macular degeneration (AMD).

DESIGN

Nested case-control study and retrospective cohort study.

METHODS

setting: Two patient cohorts from British Columbia, Canada.

STUDY POPULATION

Patients with wet AMD.

INTERVENTION

For the cohort study, patients who received the first intravitreal bevacizumab; for the nested case-control study, repeated injections of intravitreal bevacizumab.

MAIN OUTCOME MEASURES

Myocardial infarction for the retrospective cohort study; myocardial infarction and stroke for the nested case-control study.

RESULTS

In the cohort analysis, there were 2564 AMD subjects not on a vascular endothelial growth factor (VEGF) inhibitor and 5644 subjects receiving intravitreal bevacizumab. The rate of myocardial infarction (MI) among bevacizumab users was 11/1000 person-years, compared to 14.9/1000 person-years in nonusers. The adjusted rate ratio (RR) for MI was 0.70 (95% confidence interval [CI]: 0.50-1.00) and 0.74 (0.46-1.20) for the propensity score-adjusted analysis. In the nested case-control analysis there were 7452 new users of VEGF inhibitors, within which there were 313 cases of MI with 3130 matched controls. The adjusted RR for MI among those receiving 3 or more injections compared to those receiving fewer than 3 was 0.71 (95% CI: 0.41-1.22). Also in the nested case-control analysis, the adjusted RR for stroke was 0.81 (95% CI: 0.39-1.65) for those receiving ≥4 injections vs those receiving fewer than 4 injections.

CONCLUSION

Single or repeated doses of intravitreal bevacizumab were not shown to increase the risk of myocardial infarction or stroke in patients with wet AMD.

Use of Self-Matching to Control for Stable Patient Characteristics While Addressing Time-Varying Confounding on Treatment Effect: A Case Study of Older Intensive Care Patients

Exposure-crossover design offers a non-experimental option to control for stable baseline confounding through self-matching while examining causal effect of an exposure on an acute outcome. This study extends this approach to longitudinal data with repeated measures of exposure and outcome using data from a cohort of 340 older medical patients in an intensive care unit (ICU). The analytic sample included 92 patients who received ≥1 dose of haloperidol, an antipsychotic medication often used for patients with delirium. Exposure-crossover design was implemented by sampling the 3-day time segments prior (Induction) and posterior (Subsequent) to each treatment episode of receiving haloperidol. In the full cohort, there was a trend of increasing delirium severity scores (Mean±SD: 4.4±1.7) over the course of the ICU stay. After exposure-crossover sampling, the delirium severity score decreased from the Induction (4.9) to the Subsequent (4.1) intervals, with the treatment episode falling in-between (4.5). Based on a GEE Poisson model accounting for self-matching and within-subject correlation, the unadjusted mean delirium severity scores was −0.55 (95% CI: −1.10, −0.01) points lower for the Subsequent than the Induction intervals. The association diminished by 32% (−0.38, 95%CI: −0.99, 0.24) after adjusting only for ICU confounding, while being slightly increased by 7% (−0.60, 95%CI: −1.15, −0.04) when adjusting only for baseline characteristics. These results suggest that longitudinal exposure-crossover design is feasible and capable of partially removing stable baseline confounding through self-matching. Loss of power due to eliminating treatment-irrelevant person-time and uncertainty around allocating person-time to comparison intervals remain methodological challenges.