Nonarteritic Anterior Ischemic Optic Neuropathy and the Risk of Dementia: A Nationwide Cohort Study.

BACKGROUND AND OBJECTIVES: While emerging theories suggest that vascular dysfunction may occur concurrently with the amyloid cascade in Alzheimer disease (AD) pathogenesis, the role of vascular components as primary neurodegeneration triggers remains uncertain. The aim of this retrospective, population-based cohort study conducted in Korea was to explore the link between nonarteritic anterior ischemic optic neuropathy (NAION) and dementia risk. METHODS: In this nationwide, population-based, retrospective cohort study, we identified newly diagnosed NAION from 2010 to 2017 in the Korean National Health Insurance Service database. The primary outcome was new dementia diagnoses confirmed by new ICD-10 claims coupled with antidementia medication prescriptions. We assessed dementia risk using hazard ratios (HRs) with 95% CIs over an average 2.69-year follow-up after a 1-year lag period. RESULTS: The cohort consisted of 42,943 patients with NAION and 214,715 age-matched and sex-matched controls without NAION (mean age 61.37 years ± 10.75 SD, 55.48% female). The study found a higher risk of all-cause dementia (ACD; HR 1.28, 95% CI 1.20-1.36), AD (HR 1.27, 95% CI 1.18-1.36), vascular dementia (VaD; HR 1.31, 95% CI 1.09-1.58), and other dementia (HR 1.39, 95% CI 1.11-1.73) among patients with NAION, regardless of other potential confounding factors such as age, sex, lifestyle behaviors, economic status, and preexisting health conditions. In subgroup analysis, the associations between NAION and ACD were stronger in the younger age group (HR 1.83 for those younger than 65 years vs 1.23 for those 65 years or older; p for interaction <0.001). Moreover, the association of NAION with both ACD and VaD was particularly strong among current smokers. DISCUSSION: We found a significant association between NAION and increased risk for ACD, AD, VaD, and other dementia even after adjusting for potential confounders such as lifestyle, health conditions, and demographic factors within a nationwide cohort. This study highlights the potential role of vascular pathology in dementia progression and suggests that NAION may serve as a robust predictor for dementia, highlighting the need for comprehensive neurologic assessment in patients with NAION. Further research is needed to clarify the association between NAION and dementia risk.

Risk of Nonarteritic Anterior Ischemic Optic Neuropathy in Patients Prescribed Semaglutide.

Importance: Anecdotal experience raised the possibility that semaglutide, a glucagon-like peptide 1 receptor agonist (GLP-1 RA) with rapidly increasing use, is associated with nonarteritic anterior ischemic optic neuropathy (NAION). Objective: To investigate whether there is an association between semaglutide and risk of NAION. Design, Setting, and Participants: In a retrospective matched cohort study using data from a centralized data registry of patients evaluated by neuro-ophthalmologists at 1 academic institution from December 1, 2017, through November 30, 2023, a search for International Statistical Classification of Diseases and Related Health Problems, Tenth Revision code H47.01 (ischemic optic neuropathy) and text search yielded 16 827 patients with no history of NAION. Propensity matching was used to assess whether prescribed semaglutide was associated with NAION in patients with type 2 diabetes (T2D) or overweight/obesity, in each case accounting for covarying factors (sex, age, systemic hypertension, T2D, obstructive sleep apnea, obesity, hyperlipidemia, and coronary artery disease) and contraindications for use of semaglutide. The cumulative incidence of NAION was determined with the Kaplan-Meier method and a Cox proportional hazards regression model adjusted for potential confounding comorbidities. Data were analyzed from December 1, 2017, through November 30, 2023. Exposures: Prescriptions for semaglutide vs non-GLP-1 RA medications to manage either T2D or weight. Main Outcomes and Measures: Cumulative incidence and hazard ratio of NAION. Results: Among 16 827 patients, 710 had T2D (194 prescribed semaglutide; 516 prescribed non-GLP-1 RA antidiabetic medications; median [IQR] age, 59 [49-68] years; 369 [52%] female) and 979 were overweight or obese (361 prescribed semaglutide; 618 prescribed non-GLP-1 RA weight-loss medications; median [IQR] age, 47 [32-59] years; 708 [72%] female). In the population with T2D, 17 NAION events occurred in patients prescribed semaglutide vs 6 in the non-GLP-1 RA antidiabetes cohort. The cumulative incidence of NAION for the semaglutide and non-GLP-1 RA cohorts over 36 months was 8.9% (95% CI, 4.5%-13.1%) and 1.8% (95% CI, 0%-3.5%), respectively. A Cox proportional hazards regression model showed higher risk of NAION for patients receiving semaglutide (hazard ratio [HR], 4.28; 95% CI, 1.62-11.29); P < .001). In the population of patients who were overweight or obese, 20 NAION events occurred in the prescribed semaglutide cohort vs 3 in the non-GLP-1 RA cohort. The cumulative incidence of NAION for the semaglutide vs non-GLP-1 RA cohorts over 36 months was 6.7% (95% CI, 3.6%-9.7%) and 0.8% (95% CI, 0%-1.8%), respectively. A Cox proportional hazards regression model showed a higher risk of NAION for patients prescribed semaglutide (HR, 7.64; 95% CI, 2.21-26.36; P < .001). Conclusions and Relevance: This study's findings suggest an association between semaglutide and NAION. As this was an observational study, future study is required to assess causality.

Validity of Administrative Coding for Nonarteritic Ischemic Optic Neuropathy.

BACKGROUND: Administrative claims have been used to study the incidence and outcomes of nonarteritic ischemic optic neuropathy (NAION), but the validity of International Classification of Diseases (ICD)-10 codes for identifying NAION has not been examined. METHODS: We identified patients at 3 academic centers who received ≥1 ICD-10 code for NAION in 2018. We abstracted the final diagnosis from clinical documentation and recorded the number of visits with an NAION diagnosis code. We calculated positive predictive value (PPV) for the overall sample and stratified by subspecialty and the number of diagnosis codes. For patients with ophthalmology or neuro-ophthalmology visit data, we recorded presenting symptoms, examination findings, and laboratory data and calculated PPV relative to case definitions of NAION that incorporated sudden onset of symptoms, optic disc edema, afferent pupillary defect, and other characteristics. RESULTS: Among 161 patients, PPV for ≥1 ICD-10 code was 74.5% (95% CI: 67.2%-80.7%). PPV was similar when restricted to patients who had visited an ophthalmologist (75.8%, 95% CI: 68.4%-82.0%) but increased to 86.8% when restricted to those who had visited neuro-ophthalmologists (95% CI: 79.2%-91.9%). Of 113 patients with >1 ICD-10 code and complete examination data, 37 (32.7%) had documented sudden onset, optic disc swelling, and an afferent pupillary defect (95% CI: 24.7%-42.0%). Of the 76 patients who did not meet these criteria, 54 (71.0%) still received a final clinical diagnosis of NAION; for most (41/54, 75.9%), this discrepancy was due to lack of documented optic disc edema. CONCLUSIONS: The validity of ICD-10 codes for NAION in administrative claims data is high, particularly when combined with provider specialty.

Reexamining the Incidence of Nonarteritic Anterior Ischemic Optic Neuropathy: A Rochester Epidemiology Project Study.

BACKGROUND: This study aims to determine the population-based incidence and characterize the features of nonarteritic anterior ischemic optic neuropathy (NAION) using the Rochester Epidemiology Project (REP). METHODS: All patients diagnosed with an optic neuropathy from January 1, 1990, to December 31, 2016, were retrospectively reviewed to identify incident cases of NAION using the REP database, which is a record-linkage system of medical records for all patient-physician encounters among Olmsted County, Minnesota residents. The overall incidence of NAION was estimated using the age-specific and sex-specific population figures for Olmsted County census data for 1990 through 2016. Visual outcomes and risk factors were evaluated. The systemic risk factors were compared with age-matched controls. RESULTS: One hundred four patients were diagnosed with NAION during the 26-year study period. The overall age and sex adjusted incidence was 3.89 per 100,000 individuals (95% confidence interval [CI]: 3.14-4.65). The incidence was 7.73 (CI: 6.24-9.22) in patients aged 40 years or older and 10.19 (CI: 8.15-12.23) in patients aged 50 years or older. Median age at diagnosis was 65 years (range, 40-90 years), and 59 (56.7%) were male. The median logMAR visual acuity at presentation was 0.35 (Snellen equivalent of 20/40) with 14 patients (13.5%) having vision of counting fingers or worse. Among the 91 patients with final visual acuity outcome data available, the median visual acuity was 0.40 (Snellen equivalent of 20/50) with 12 patients (13.2%) having vision of counting fingers or worse. Twenty-four patients (26.4%) were noted to have final acuity at least 3 Snellen lines worse than at presentation, whereas 17 patients (18.7%) were noted to improve by at least 3 lines. The median mean deviation on automated visual field testing was -10.2 dB at presentation and -11.1 dB at follow-up. Twenty-two patients (21.2%) suffered NAION in the fellow eye; the median interval between involvement of the first and second eyes was 1.39 years. Systemic diseases present in the NAION cohort included hypertension (79.8%), diabetes mellitus (39.4%), obstructive sleep apnea (23.1%), and hyperlipidemia (74.0%), which were all statistically higher than age-matched controls. CONCLUSIONS: NAION is a relatively common optic neuropathy in elderly patients with vascular risk factors. Our data indicate that the incidence of NAION has remained relatively stable in the population of Olmsted County over the past 4 decades.

Nonarteritic anterior ischemic optic neuropathy and incidence of Parkinson's disease based on a nationwide population based study.

This study aimed to investigate the association between nonarteritic anterior ischemic optic neuropathy (NAION) and Parkinson's disease (PD) using a retrospective, nationwide, population-based cohort in South Korea. This study utilized data from the Korean National Health Insurance database, including 43,960 NAION patients and 219,800 age- and sex-matched controls. Cox proportional hazards regression models were used to assess the risk of developing PD in the NAION group compared to the control group after adjusting for various confounding factors. Subgroup analyses were conducted based on sex, age, and comorbidities. The incidence rate of PD was higher in the NAION group (1.326 per 1000 person-years) than in the control group (0.859 per 1000 person-years). After adjusting for confounding factors, the risk of developing PD was significantly higher in the NAION group (adjusted hazard ratio [aHR] 1.516, 95% confidence interval [CI] 1.300-1.769). Subgroup analyses did not reveal a significant difference in the risk of PD development based on sex, age, or comorbidities. This retrospective, nationwide, population-based cohort study revealed a significant association between NAION and an increased risk of developing PD in a South Korean population. The incidence rate of PD was observed to be higher in individuals diagnosed with NAION than in age- and sex-matched controls even after adjusting for potential confounding variables, with the risk being approximately 51.6% higher in the NAION group. Further research is necessary to elucidate the underlying pathophysiological mechanisms linking NAION to PD and to determine whether similar associations exist in other ethnic and geographical populations.

Features of Peripapillary Hyperreflective Ovoid Mass-Like Structures in Nonarteritic Anterior Ischemic Optic Neuropathy Patients and Normal Controls.

Purpose: To determine the characteristics of peripapillary hyperreflective ovoid mass-like structures (PHOMS) in patients with nonarteritic anterior ischemic optic neuropathy (NAION) and in normal adults. Methods: A total of 406 included eyes were divided into four groups: acute NAION group, chronic NAION group, unaffected group, and normal eyes group. PHOMS were detected on optical coherence tomography slices from optical coherence tomography angiography scans centered on the optic nerve head (ONH). The differences in age, sex, and ONH parameters were investigated between eyes with PHOMS and eyes without PHOMS among groups. Results: The prevalence of PHOMS in acute eyes (43.48%) and fellow eyes (28.20%) was significantly higher than that in normal eyes (11.76%) (acute vs. normal, P < 0.001; fellow vs. normal, P = 0.014). In the acute group, the PHOMS score of size was negatively correlated with age in acute eyes (r = -0.486, P = 0.03). The size of PHOMS was negatively correlated with age and cup/disc ratio and positively correlated with retinal nerve fiber layer thickness in the nasal and inferior sectors in the normal groups. No differences in age, sex, ONH parameters, or visual field defects were found between eyes with PHOMS and eyes without PHOMS. Conclusions: The prevalence of PHOMS increased significantly in acute nonoptic disc drusen (NODD)-NAION eyes and fellow eyes. PHOMS could also be found among normal adults. PHOMS may be a nonspecific sign secondary to ONH edema and axoplasmic stasis. Translational Relevance: The high prevalence of PHOMS in acute NODD-NAION eyes may indicate axoplasmic stasis secondary to tissue edema.

Ocular manifestations of obstructive sleep apnea: a systematic review and meta-analysis.

BACKGROUND: The association of obstructive sleep apnea (OSA) with development of eye diseases is unclear. This current systematic review and meta-analysis attempts to summarize and analyze associations between OSA and ocular disorders in the literature. METHODS: PubMed, EMBASE, Google Scholar, Web Of Science, and Scopus databases were searched from 1901 to July 2022 in accordance with the Preferred Reporting in Systematic Review & Meta-Analysis (PRISMA). Our primary outcome assessed the association between OSA and the odds of developing floppy eyelid syndrome (FES), glaucoma, non-arteritic anterior ischemic optic neuropathy (NAION), retinal vein occlusion (RVO), keratoconus (KC), idiopathic intracranial hypertension (IIH), age-related macular degeneration (AMD), and central serous chorioretinopathy (CSR) through odds ratio calculated at the 95% confidence interval. RESULTS: Forty-nine studies were included for systematic review and meta-analysis. The pooled OR estimate was highest for NAION [3.98 (95% CI 2.38, 6.66)], followed by FES [3.68 (95% CI 2.18, 6.20)], RVO [2.71(95% CI 1.83, 4.00)], CSR [2.28 (95% CI 0.65, 7.97)], KC [1.87 (95% CI 1.16, 2.99)], glaucoma [1.49 (95% CI 1.16, 1.91)], IIH [1.29 (95% CI 0.33, 5.01)], and AMD [0.92 [95% CI 0.24, 3.58] All observed associations were significant (p < 0.001) aside from IIH and AMD. CONCLUSION: OSA is significantly associated with NAION, FES, RVO, CSR, KC, and glaucoma. Clinicians should be informed of these associations so early recognition, diagnosis, and treatment of eye disorders can be addressed in at-risk groups, and early referral to ophthalmic services is made to prevent vision disturbances. Similarly, ophthalmologists seeing patients with any of these conditions should consider screening and referring patients for assessment of possible OSA.

Non-Arteritic Ischemic Optic Neuropathy Following COVID-19 Vaccination in Korea: A Case Series.

BACKGROUND: To report the clinical manifestations of non-arteritic anterior ischemic optic neuropathy (NAION) cases after coronavirus disease 2019 (COVID-19) vaccination in Korea. METHODS: This multicenter retrospective study included patients diagnosed with NAION within 42 days of COVID-19 vaccination. We collected data on vaccinations, demographic features, presence of vascular risk factors, ocular findings, and visual outcomes of patients with NAION. RESULTS: The study included 16 eyes of 14 patients (6 men, 8 women) with a mean age of 63.5 ± 9.1 (range, 43-77) years. The most common underlying disease was hypertension, accounting for 28.6% of patients with NAION. Seven patients (50.0%) had no vascular risk factors for NAION. The mean time from vaccination to onset was 13.8 ± 14.2 (range, 1-41) days. All 16 eyes had disc swelling at initial presentation, and 3 of them (18.8%) had peripapillary intraretinal and/or subretinal fluid with severe disc swelling. Peripapillary hemorrhage was found in 50% of the patients, and one (6.3%) patient had peripapillary cotton-wool spots. In eight fellow eyes for which we were able to review the fundus photographs, the horizontal cup/disc ratio was less than 0.25 in four eyes (50.0%). The mean visual acuity was logMAR 0.6 ± 0.7 at the initial presentation and logMAR 0.7 ± 0.8 at the final visit. CONCLUSION: Only 64% of patients with NAION after COVID-19 vaccination have known vascular and ocular risk factors relevant to ischemic optic neuropathy. This suggests that COVID-19 vaccination may increase the risk of NAION. However, overall clinical features and visual outcomes of the NAION patients after COVID-19 vaccination were similar to those of typical NAION.

Nonarteritic Anterior Ischemic Optic Neuropathy After Cataract Surgery: A Systematic Review and Meta-Analysis.

BACKGROUND: Nonarteritic anterior ischemic optic neuropathy (NAION) has been reported to occur after cataract surgery. It is not clearly established whether cataract surgery increases the risk of NAION over baseline. EVIDENCE ACQUISITION: Medline, PubMed, Embase, and Cochrane Central registers were systematically searched for eligible studies reporting on postcataract surgery NAION (psNAION) within 1 year. All peer-reviewed publications with events n ≥ 10 were included. Pooled incidence and odds/hazard ratios and 95% confidence intervals (CIs) were extracted and calculated using random effect models for early and delayed psNAION. Time to event data were pooled for temporal analysis of psNAION events within the first year. This systematic review was registered (PROSPERO CRD42021274383). RESULTS: Nine articles met the selection criteria with five studies suitable for meta-analysis. A total of 320 psNAION cases, 1,307 spontaneous NAION (sNAION) cases, 1,587,691 cataract surgeries, and 1,538,897 noncataract surgery controls were included. Pooling of 63,823 cataract surgeries and 161,643 controls showed a hazard ratio of 4.6 (95% CI 2.7-7.8) of psNAION within 1 year of surgery. Pooled unadjusted incidence of psNAION within 2 months was 99.92 (95% CI 38.64-161.19) per 100,000/year, psNAION within 1 year was 32.36 (95% CI 9.38-55.34) per 100,000/year, and sNAION was 8.87 (95% CI 2.12-15.62) per 100,000/year. psNAION cases were older by a mean of 7.6 years; otherwise, pooled odds ratios for baseline risk factors in psNAION vs. sNAION cases were not statistically significant. psNAION within the first year peaked within 72 hrs and at 6 weeks after the surgery with 73% of cases occurring within 6 months. CONCLUSION: The risk of NAION after cataract surgery is four times greater within the first year and usually occurs within 6 months. However, the absolute risk remains low at 1 in 1,000-3,100 surgeries and is unlikely to warrant extra mention for consenting.

Bilateral Simultaneous Nonarteritic Anterior Ischemic Optic Neuropathy: Demographics, Risk Factors, and Visual Outcomes.

BACKGROUND: Although nonarteritic anterior ischemic optic neuropathy is a well-known cause of vision loss, it typically presents unilaterally. Simultaneous, bilateral nonarteritic anterior ischemic optic neuropathy (sNAION) is rare and poorly studied in comparison. This study seeks to characterize the clinical features and risk factors of patients with sNAION compared with unilateral NAION (uNAION). METHODS: In this retrospective case-control study, we reviewed 76 eyes (38 patients) with sNAION and 38 eyes (38 patients) with uNAION (controls) from 4 academic institutions examined between 2009 and 2020. Demographic information, medical history, medication use, symptom course, paraclinical evaluation, and visual outcomes were collected for all patients. RESULTS: No significant differences were observed in demographics, comorbidities and their treatments, and medication usage between sNAION and uNAION patients. sNAION patients were more likely to undergo an investigative work-up with erythrocyte sedimentation rate measurement ( P = 0.0061), temporal artery biopsy ( P = 0.013), lumbar puncture ( P = 0.013), and MRI ( P < 0.0001). There were no significant differences between the 2 groups for visual acuity, mean visual field deviation, peripapillary retinal nerve fiber layer thickness, or ganglion cell-inner plexiform layer thickness at presentation, nor at final visit for those with ≥3 months of follow-up. The sNAION eyes with ≥3 months of follow-up had a smaller cup-to-disc ratio (CDR) at final visit ( P = 0.033). Ten patients presented with incipient NAION, of which 9 suffered vision loss by final visit. CONCLUSION: Aside from CDR differences, the risk factor profile and visual outcomes of sNAION patients seem similar to those of uNAION patients, suggesting similar pathophysiology.

Influence of obstructive sleep apnea syndrome on the contralateral optic nerve in patients with unilateral nonarteritic anterior ischemic optic neuropathy.

STUDY OBJECTIVES: The aim was to quantitatively evaluate the influence of obstructive sleep apnea syndrome (OSAS) on the morphology and function of the contralateral optic nerve in patients with unilateral nonarteritic anterior ischemic optic neuropathy (NAION). METHODS: Fifty patients with unilateral NAION were divided into non-OSAS (n = 16), mild OSAS (n = 15), and moderate-severe OSAS (n = 19) groups based on their apnea-hypopnea index (AHI) scores. Systemic and ocular characteristics were compared between these groups. Spearman correlation and multiple linear regression analyses were used to determine the independent factors that most influenced the thickness of the peripapillary retinal nerve fiber layer (pRNFL). RESULTS: Body mass index and hypertension occurrence were higher in the moderate-severe OSAS group than in the non-OSAS group. Temporal pRNFL was thinner in the moderate-severe group than in the mild and non-OSAS groups, whereas no difference was found between the mild and non-OSAS groups. Spearman correlation showed that the AHI (r = -.469, P = .001) and the percentage of total sleep time with oxygen saturation < 90% (T90%; r = -.477, P = .001) correlated with temporal pRNFL thickness. Multiple linear regression showed that the AHI was negatively associated with temporal pRNFL thickness (ß = -0.573, P = .003). CONCLUSIONS: OSAS may cause subclinical temporal pRNFL thinning in the contralateral optic nerve among patients with unilateral NAION without any significant change in visual function. Advanced optic nerve observation and intervention may be warranted in patients with moderate-severe OSAS. CITATION: Li X, Zhang Y, Guo T, et al. Influence of obstructive sleep apnea syndrome on the contralateral optic nerve in patients with unilateral nonarteritic anterior ischemic optic neuropathy. J Clin Sleep Med. 2023;19(2):347-353.

A Taiwan Nationwide Population-Based Study of Socio-Demographic Factors and Comorbid Conditions Associated with Non-Arteritic Anterior Ischaemic Optic Neuropathy.

AIMS: The aim of the study was to investigate the socio-demographic factors and systemic conditions associated with non-arteritic anterior ischaemic optic neuropathy (NAION). METHODS: This was a nationwide population-based retrospective case-controlled study that recruited 9,261 NAION patients selected from the Taiwan National Health Insurance Research Database. The control group consisted of 9,261 age-, sex-, and index date-matched non-NAION patients recruited from the Taiwan Longitudinal Health Insurance Database, 2000. NAION was designated in the database by the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) as "code 377.41: ischaemic optic neuropathy without ICD-9-CM code 446.5: giant cell arteritis." Associated socio-demographic factors and systemic medical conditions were analysed using the McNemar's test, and continuous variables were analysed using the paired t test. The odds ratio (OR) and adjusted OR of developing NAION were compared using univariate logistic regression and multivariable logistic regression analyses, respectively. RESULTS: Patients with systemic conditions such as diabetes mellitus, hypertension, hyperlipidaemia, chronic kidney disease, and hypotension were more likely to develop NAION than controls (adjusted OR = 1.81, 95% confidence interval [CI] = 1.67-1.97, p < 0.0001; adjusted OR = 1.46, 95% CI = 1.36-1.57, p < 0.0001; adjusted OR = 1.44, 95% CI = 1.33-1.57, p < 0.0001; adjusted OR = 3.26, 95% CI = 2.65-4.01, p < 0.0001; adjusted OR = 2.32, 95% CI = 1.31-4.10, p = 0.0039, respectively). CONCLUSIONS: NAION is strongly associated with diabetes mellitus, hypertension, hyperlipidaemia, chronic kidney disease, and hypotension.

Metabolic syndrome and its components are associated with non-arteritic anterior ischaemic optic neuropathy.

PURPOSE: To determine whether metabolic syndrome (MetS) is a risk factor for various forms of optic neuropathy including non-arteritic anterior ischaemic optic neuropathy (NAION). METHODS: This population-based analysis identified patients ≥40 years of age in Olmsted County, Minnesota, USA using the Rochester Epidemiology Project 2005-2018. Patients with MetS were identified if three or more of the five standard criteria for diagnosing MetS were present: systemic hypertension, hyperglycaemia, hypertriglyceridaemia, reduced high-density lipoprotein cholesterol (hypoalphalipoproteinaemia) and central adiposity defined by increased body mass index. Charts of patients identified as having an optic neuropathy were reviewed to record specific diagnoses and compared with patients without ocular pathology other than cataract. The odds ratio (OR) of association with MetS was calculated and adjusted for age, sex and race with multivariate analysis for the various optic neuropathies. RESULTS: Patients with MetS were more likely to have an optic neuropathy than those without (OR 2.2, p<0.001). After adjusting for age, sex and race, the only optic neuropathy found to be significantly associated with MetS was NAION (OR 6.17, p=0.002). For patients with NAION, though each individual component of MetS was individually significantly associated with MetS, further analysis suggested that hypertriglyceridaemia, hypoalphalipoproteinaemia and hyperglycaemia were likely the key drivers in the overall significance between NAION and MetS. CONCLUSION: Patients with MetS were more likely to have NAION. Further studies are needed to determine whether MetS is a modifiable risk factor for NAION.

Perioperative Ischemic Optic Neuropathy after Cardiac Surgery: Development and Validation of a Preoperative Risk Prediction Model.

OBJECTIVE: Previous studies identified risk factors for ischemic optic neuropathy (ION) after cardiac surgery; however, there is no easy-to-use risk calculator for the physician to identify high-risk patients for ION before cardiac surgery. The authors sought to develop and validate a simple-to-use predictive model and calculator to assist with preoperative identification of risk and informed consent for this rare but serious complication. DESIGN: Retrospective case-control study. SETTING: Hospital discharge records. PATIENTS: A total of 5,561,177 discharges in the National Inpatient Sample >18 years of age, with procedure codes for coronary artery bypass grafting, heart valve repair/replacement, or left ventricular assist device insertion. INTERVENTIONS: All patients had undergone cardiac surgery. MEASUREMENTS AND MAIN RESULTS: Known preoperative risk factors for ION after cardiac surgery were assessed to develop a risk score and prediction model. This model was validated internally using the split-sample method. There were 771 cases of ION among 5,561,177 patients in the National Inpatient Sample. The risk factors for ION used in the model were carotid artery stenosis, cataract, diabetic retinopathy, macular degeneration, glaucoma, male sex, and prior stroke; whereas uncomplicated diabetes decreased risk. With the internal validation, the predictive model had an area under the receiver operating characteristic curve of 0.66. A risk score cutoff ≥3 had 98.4% specificity. CONCLUSIONS: This predictive model, based on previously identified preoperative factors, predicted risk of perioperative ION with a fair area under the receiver operating characteristic curve. This predictive model could enable screening to provide a more accurate risk assessment for ION, and consent process for cardiac surgery.

Post-cataract surgery optic neuropathy: a chronological narrative review of the literature and speculation on pathogenesis.

PURPOSE OF REVIEW: To appraise the literature on the incidence of an acute anterior optic neuropathy resembling spontaneous nonarteritic anterior ischemic optic neuropathy (NAION) following uncomplicated cataract surgery and to explore the proposed pathogenesis of both immediate and delayed onset post-cataract surgery optic neuropathy (PCSON). RECENT FINDINGS: A number of case reports, case series, and retrospective case-controlled, big data, and population-based studies have identified an apparent association between cataract surgery and the occurrence of an acute anterior optic neuropathy that can either be immediate or delayed in onset. However, a recent study found no link between modern day cataract surgery and an increased risk of an acute anterior optic neuropathy. SUMMARY: Immediate PCSON appears to be related to negative perfusion pressure at the level of the optic disc due to increased intraocular pressure. The pathogenesis of delayed PCSON is unknown but probably multifactorial. Patients who have experienced spontaneous NAION or PCSON in one eye may be at risk of PCSON in the fellow eye.

Cardiometabolic factors and risk of non-arteritic anterior ischemic optic neuropathy: a systematic review and meta-analysis.

PURPOSE: The purpose of this systematic review and meta-analysis of the literature is to evaluate the association between cardiometabolic risk factors (hypertension, diabetes mellitus, hypercholesterolemia/dyslipidemia, HDL cholesterol, LDL cholesterol, lipoprotein(a), and triglycerides) and non-arteritic anterior ischemic optic neuropathy (NAION). METHODS: Pertinent publications were identified through a systematic search in PubMed and EMBASE databases, without language restrictions. The pooled odds ratios (OR) and standardized mean differences (SMD), with their 95% confidence intervals (95% CI) were estimated using random effects (DerSimonian Laird) models, as appropriate. A set of subgroup analyses and meta-regression analysis models were performed. RESULTS: Twenty-one studies (including 1560 patients with NAION and 2292 controls), examining the association between NAION and cardiometabolic risk factors, were eligible for the systematic review and meta-analysis. Hypertension (pooled OR = 1.50; 95% CI: 1.16-1.94), diabetes mellitus (pooled OR = 1.71; 95% CI: 1.33-2.21), and hypercholesterolemia/dyslipidemia (pooled OR = 2.00; 95% CI: 1.53-2.62) were associated with NAION. Among the components of dyslipidemia, higher serum triglycerides were associated with NAION, with a medium effect size (SMD = + 0.58, 95% CI: + 0.12 to + 1.04), whereas synthesis of four studies reporting on HDL and LDL cholesterol did not reveal any significant associations. A significant association between NAION and higher serum lipoprotein(a) levels (pooled OR = 2.88; 95%CI: 1.01-8.21) was also noted. CONCLUSIONS: This systematic review and meta-analysis found that NAION was associated with cardiometabolic factors, suggesting that vascular dysfunction may be implicated in the pathogenesis of the disease. Our findings may alert health care providers to try modifying these risk factors for NAION prevention.

Incidence of Ischemic Optic Neuropathy After Cardiopulmonary Bypass: 20-Year Experience.

OBJECTIVE: This study evaluated the incidence and risk factors for ischemic optic neuropathy (ION) as a complication of cardiac surgery requiring cardiopulmonary bypass (CPB). DESIGN: Retrospective chart review of prospectively collected data at a tertiary care center. SETTING: Single tertiary academic referral center. PARTICIPANTS: This study comprised 44,568 cardiac surgery patients who underwent CPB between January 1, 1995, and January 5, 2017, using the Society of Thoracic Surgeons database and cross-matching it with International Classification of Diseases codes for visual changes. INTERVENTIONS: None; this was a retrospective chart review. MEASUREMENTS AND MAIN RESULTS: Six patients initially were identified as experiencing visual changes. Only 1 patient from 44,568 cardiac surgeries with CPB between January 1, 1995, and January 5, 2017, experienced ION, for an incidence 0.22 per 10,000. Because only 1 patient experienced ION, the authors were unable to determine risk factors for this complication; however, the nadir perioperative hemoglobin in the affected patient was 7.3 g/dL (postoperative). CONCLUSION: The incidence of ION decreased from 6 per 10,000 in the authors' previous study from 1976-1994 to 0.22 per 10,000 in the present study. Because of the low incidence of this dreaded complication, the authors were not able to identify risk factors for ION. Practice improvements (eg, transition to membrane oxygenators, blood transfusion guidelines, less- invasive surgical options for high-risk patients) during the time between the authors' studies likely affected the incidence reduction.