Prevalence and associations of asymptomatic retinal emboli in Latinos: the Los Angeles Latino Eye Study (LALES)

Factors Associated With Incidental Retinal Emboli in the U.S. Adult Population

PURPOSE

We sought to estimate the prevalence of incidental retinal emboli and identify associated factors using a nationally representative sample of the U.S.

POPULATION

DESIGN

Cross-sectional study.

METHODS

We included adult (age ≥40 years) participants of the 2005-2008 National Health and Nutrition Examination Survey (NHANES). Incidental retinal emboli were identified through retinal fundus photography. Multivariable logistic regression was used to determine the association between the presence of retinal emboli and sociodemographic, lifestyle, and clinical factors (age, sex, race/ethnicity, education, income, smoking, alcohol use, body mass index [BMI], hypertension, diabetes, hypercholesterolemia, and history of cardiovascular disease).

RESULTS

This study included 5,764 adults (53% female). Incidental retinal emboli were identified in 0.7% (39/5764) of individuals. The survey-weighted prevalence of retinal emboli increased with age, from 0.1% in participants 40-49 years of age to 1.4% in participants≥70 years of age. The prevalence did not differ by sex or race/ethnicity. Factors associated with retinal emboli after adjusting for age and sex included underweight BMI (odds ratio [OR] 7.24 [95% confidence interval {CI} 1.06-49.3]), current smoking (OR 6.16 [95% CI 1.49-25.5]), low household income (OR 4.41 [95% CI 1.3-15.0]), and hypertension (OR 2.67 [95% CI 1.31-5.44]).

CONCLUSIONS

In a cohort representative of the U.S. adult population, the prevalence of incidental retinal emboli increased with age but did not differ by sex, race, or ethnicity. Further investigation into the potential association of socioeconomic and nutritional status with retinal emboli may enable opportunities to identify individuals with underlying cardiovascular risk.

Systematic review of the relationship between Hollenhorst plaques and cerebrovascular events

BACKGROUND

Few studies have evaluated the association between asymptomatic cholesterol emboli on fundoscopy (known as Hollenhorst plaque) and the subsequent risk of stroke or death.¹.

AIM

To evaluate the association between the presence of asymptomatic cholesterol retinal emboli and the risk of cerebrovascular events, with assessment of the need for carotid intervention.

METHODS

PubMed, Embase, and Cochrane Library databases were searched using appropriate terms. The systematic review was conducted according to PRISMA guidelines.

RESULTS

Initial search revealed 43 in Medline and 46 in Embase databases. Twenty-four potentially eligible studies were included after duplicate and non-related studies were excluded based on title and abstract. Three more studies were identified from reference lists. Seventeen studies were included in the final analysis. Asymptomatic cholesterol emboli were present in 1343 patients. Approximately 17.8% (n = 181) had history of either cerebro-vascular Accident (CVA) or transient ischaemic attacks (TIAs) at presentation (more than 6 months). Nine studies mentioned the incidence of cerebrovascular events during follow-up. Of 780 patients, 93 evolved to stroke, TIAs, or death from a major carotid event during the follow-up period (6-86 m), an incidence of about 12%. Death due to stroke was documented in 3 studies (n = 12).

CONCLUSION

The presence of asymptomatic retinal emboli indicates a risk of a cerebrovascular event when compared to patients with no plaques seen on fundoscopy. The evidence suggests that these patients warrant referral for medical optimization of cardiovascular risk factors. Currently, there is no recommendation to support carotid endarterectomy in patients with Hollenhorst plaques, or retinal emboli, and further studies are needed to assess this.

Asymptomatic retinal emboli and current practice guidelines: a review

Asymptomatic retinal emboli are found in 1-3% of patients on routine fundus examination. As the use of teleretinal imaging for diabetic patients and ocular photography continues to increase, the number of asymptomatic retinal emboli found will also increase. This article will discuss the different aetiologies of retinal emboli and will present an overview of the recommended referrals for further systemic testing and treatment. It is important to communicate well with the primary care physician when asymptomatic retinal emboli are detected to ensure the appropriate investigations are undertaken.

Topical Medication Adherence and Visual Field Progression in Open-angle Glaucoma: Analysis of a Large US Health Care System

PRCIS

Modeling of visual field and pharmacy data (Kaiser Permanente, 2001 to 2014) from open-angle/pseudoexfoliation glaucoma patients in clinical practice indicated a significant inverse association between the level of medication adherence and rate of visual field progression.

PURPOSE

The aim was to quantify the effect of nonadherence to topical hypotensive medication on glaucomatous visual field progression in clinical practice.

METHODS

Retrospective analysis of combined visual field and pharmacy data from Kaiser Permanente Southern California's HealthConnect electronic health record database. Patients with a diagnosis of primary open-angle glaucoma or pseudoexfoliation glaucoma (2001 to 2011) and ≥3 subsequent visual field tests of the same Swedish Interactive Threshold Algorithm type were followed up from first medication fill to final visual field test. Medication adherence (proportion of days covered) was estimated from pharmacy refill data. A conditional growth model was used to estimate the effect of adherence level in modifying the progression of mean deviation over time after adjusting for potential confounders, including age, sex, race/ethnicity, baseline glaucoma severity, and comorbidity.

RESULTS

In total, 6343 eligible patients were included in the study and followed for (mean) 5.8 years; average treatment adherence during follow-up was 73%. After controlling for confounders and the interaction between time and baseline disease severity, the model indicated that mean deviation progression was significantly (P=0.006) reduced by 0.006 dB per year for each 10% (absolute) increase in adherence. Model estimates of time to glaucoma progression (mean deviation change -3 dB from baseline) were 8.3 and 9.3 years for patients with adherence levels of 20% and 80%, respectively.

CONCLUSIONS

Improving patient adherence to topical glaucoma medication may result in slower deterioration in visual function over time.

Arterial Occlusions to the Eye: From Retinal Emboli to Ocular Ischemic Syndrome

: Abstract: A loss or lack of blood supply to the eye can result in acute loss of vision. The site of ischemia may be at the level of the retinal arterioles, the central retinal artery, or further back at the ophthalmic and internal carotid artery. Recognizing the symptoms and signs are important to help prevent permanent ischemic and irreversible blindness. The objective of this review article is to provide the general ophthalmologists with information on how to recognize the symptoms and to best manage these patients. The management is to investigate for the cause of the transient monocular visual loss and to apply secondary prevention to address atherosclerotic risk factors to prevent further ischemic events like a stroke.

Prevalence of Retinal Emboli and Acute Retinal Artery Occlusion in Acute Ischemic Stroke

OBJECTIVE

In population-based studies asymptomatic retinal emboli occur in .32%-2.9% of people. Retinal artery occlusion (RAO) may occur concurrently with cerebral stroke but the frequency is unknown. No study has examined how commonly retinal emboli occur in the acute stroke population. We aimed to assess the prevalence of retinal emboli and RAO at the time of carotid territory ischemic stroke.

METHODS

Patients were enrolled prospectively after onset of symptoms consistent with the diagnosis of carotid territory ischemic stroke. Every participant underwent pharmacologic dilation of both pupils and bedside funduscopic examination. Emboli were classified as cholesterol, calcific, platelet/fibrin, or other and categorized by the side of occurrence. Stroke was classified as atheroembolic, cardioembolic, embolic stroke of undetermined source, lacunar, or other. Acute RAO was diagnosed by direct visualization of ischemic retinal whitening.

RESULTS

Sixty-five patients were enrolled with a mean age of 59.2 years; 23 were female (35.4%). Eleven of 65 subjects (16.9%) had retinal emboli visible on funduscopy; all were cholesterol emboli except a single platelet/fibrin embolus in a patient with atheroembolic source. Six patients (9%) had acute RAO and no RAO was seen in the lacunar or undetermined source subgroups.

CONCLUSIONS

Retinal emboli occurred more than 10 times more frequently in the acute stroke patient than in large population-based studies. RAOs also occurred concurrently with ischemic stroke. Although emboli were seen in patients with atheroembolic and cardioembolic sources, all patients with carotid disease had emboli in the ipsilateral eye. Future studies are required to determine if the presence of retinal emboli or RAO may help elucidate an etiology in patients suffering from embolic stroke of undetermined source.

Review of the association between retinal microvascular characteristics and eye disease

Computerized retinal imaging technologies enable the static and dynamic measurement of a range of retinal microvascular parameters. Large population-based studies have reported associations between these microvascular indices and various ophthalmic diseases including diabetes, age-related macular degeneration, retinal artery embolism, retinal vein occlusion, glaucoma and non-glaucomatous optic neuropathies. Increasingly, sophisticated imaging and analysis techniques have the potential to provide relevant clinical information regarding disease risk and progression; however, further studies are required to verify associations and strengthen the predictive power of these techniques. We summarize the current state of knowledge regarding retinal microvascular characteristics and eye disease.

Prevalence and Associations of Retinal Emboli With Ethnicity, Stroke, and Renal Disease in a Multiethnic Asian Population: The Singapore Epidemiology of Eye Disease Study

Importance

To our knowledge, population-based data on retinal emboli are limited in Asia. Besides its associations with traditional cardiovascular risk factors and stroke, associations between retinal emboli and renal disease and function remain unclear.

Objective

To examine the prevalence of and risk factors for retinal emboli in a large, contemporary, multiethnic Asian population.

Design, Setting, and Participants

This population-based cross-sectional study was conducted from 2004 to 2011 and included a total of 10 033 Chinese, Malay, and Indian persons aged 40 to 80 years residing in the general communities of Singapore. Analyses were performed from November 2016 to February 2017.

Interventions or Exposures

Retinal emboli were ascertained from retinal photographs obtained from both eyes of all participants according to a standardized protocol. Age-standardized prevalence of retinal emboli was calculated using the 2010 Singapore adult population. Risk factors were assessed from comprehensive systemic and ophthalmic examinations, interviews, and laboratory investigations.

Main Outcomes and Measures

Retinal emboli.

Results

Of the 10 033 participants, 9978 (99.5%) had gradable retinal photographs. Of these, 5057 (50.7%) were female, and 3375 (33.8%) were Indian. We identified 88 individuals (0.9%) with retinal emboli; the overall person-specific, age-standardized prevalence of retinal emboli was 0.75% (95% CI, 0.60-0.95), with the highest prevalence seen in the Indian cohort (0.98%), followed by the Chinese (0.73%) and Malay (0.44%) cohorts (P = .03). In multivariable-adjusted analysis, factors associated with prevalent retinal emboli included older age (per 5-year increase; odds ratio [OR], 1.22; 95% CI, 1.05-1.41), Indian ethnicity (compared with Malay ethnicity; OR, 3.58; 95% CI, 1.95-6.60), hypertension (OR, 1.95; 95% CI, 1.03-3.70), chronic kidney disease (OR, 2.05; 95% CI, 1.15-3.64), creatinine level (per SD increase; OR, 1.13; 95% CI, 1.05-1.21), glomerular filtration rate (per SD increase; OR, 0.67; 95% CI, 0.51-0.86), and history of stroke (OR, 3.45; 95% CI, 1.70-6.99).

Conclusions and Relevance

Based on 88 individuals among 9978 participants of 3 major Asian ethnic populations, retinal emboli were most commonly seen in Indian persons and associated with conventional cardiovascular risk factors, stroke, and chronic kidney disease. Therefore, its presence may signal vascular embolic event and damage not only in the brain but also in the kidneys. If these data are confirmed in longitudinal studies, they would suggest that persons with retinal emboli may require both general cardiovascular and renal assessment.

Assessing Patients with Asymptomatic Retinal Emboli Detected at Retinal Screening

Introduction

Asymptomatic retinal emboli have been associated with diabetes, the presence of significant carotid artery stenosis (≥70%) and an increased risk of stroke. However, there is no clear guidance on how best to investigate and manage patients found to have asymptomatic retinal emboli. Therefore, this study aimed to assess the incidence of significant carotid artery stenosis in patients found to have asymptomatic retinal emboli at diabetic retinopathy screening, and to examine disease management approaches among these patients.

Methods

Patients with new retinal emboli visible at diabetic retinopathy screening were referred to a medical retinopathy clinic and underwent examinations according to a standardized protocol, including carotid Doppler ultrasound and echocardiography. Case notes of patients referred between January 2013 and April 2014 were reviewed. Results of investigations, medication changes and the number of patients who underwent relevant surgical interventions were noted.

Results

Retinal emboli were present in 44 of 13,643 people screened (0.32%). Full data were available for 39 patients. Twenty-two patients (56%) had relevant medication changes. Nine (23%) patients had significant carotid artery stenosis. One underwent carotid endarterectomy, and eight received maximal medical therapy.

Conclusion

Significant carotid artery stenosis was not uncommon in patients with incident retinal emboli at retinal screening. The referral and investigation protocols identified individuals at risk of cerebrovascular events and led to optimized management. Pathways utilizing Doppler ultrasound and physician referral should be more widely implemented.

Retinal emboli

Retinal emboli are opacities identified in retinal arterioles and are often incidental findings on ophthalmic examination. They are generally composed of cholesterol, platelet-fibrin, or calcium and are thought to arise from carotid arteries, coronary arteries, or cardiac valves. In the general population, the estimated prevalence is 0.2% to 1.3%, and the estimated incidence is 0.9% to 2.9%. The transient nature of retinal emboli likely explains the variations between and within these reported figures. The strongest risk factor for retinal emboli is smoking, which has been reported consistently across many studies. Other likely risk factors include older age, hypertension, male sex, total cholesterol, coronary artery disease, and history of coronary artery bypass grafting. The presence of multiple risk factors, as is common in many patients, confers a higher risk for retinal emboli. Several studies suggest that retinal emboli predict an increase in stroke-related, all-cause, and possibly cardiovascular mortality. Due to these sequelae, patients often undergo further workup, most commonly carotid ultrasonography. However, given the low prevalence of significant carotid disease in patients with retinal emboli, further workup, such as carotid ultrasound, should be reserved for those with risk factors for carotid disease. All patients would benefit from medical optimization and coordinated care with the primary care physician.

Nationwide incidence of clinically diagnosed central retinal artery occlusion in Korea, 2008 to 2011

PURPOSE

To define the incidence and demographics of clinically diagnosed central retinal artery occlusion (CRAO) in Korea.

DESIGN

Nationwide population-based retrospective study using data entered into the Korean national health claims database from 2007 to 2011.

PARTICIPANTS

Data of the entire Korean population (N = 47,990,761, based on the 2010 census) were analyzed.

METHODS

We used the national health claims database to identify patients diagnosed with CRAO. Incident cases were those with no claims related to CRAO in 2007 and were included once on the earliest claims related to CRAO in the years 2008 to 2011. Incident cases had a disease-free period before diagnosis of at least 1 to 4 years. The average incidence rate of CRAO was estimated according to the entire Korean population.

MAIN OUTCOME MEASURES

The person-time incidence rates of clinically diagnosed CRAO in Korea, including the age- and sex-specific incidence rates, were estimated.

RESULTS

A total of 3464 CRAO cases (59.1% men) were identified. The incidence rate of clinically diagnosed CRAO during the study period was 1.80 per 100,000 person-years (95% confidence interval [CI], 1.74-1.86). The incidence rate among men and women was 2.15 (95% CI, 2.05-2.24) and 1.47 (95% CI, 1.39-1.54) per 100,000 person-years (male-to-female ratio, 1.47), respectively. The age-specific male-to-female ratios were constant between the ages of 30 and 89 years (range, 1.51-2.10 years). The highest incidence of 10.08 (95% CI, 8.80-11.35) per 100,000 person-years was observed in those aged 80 to 84 years (14.65 [95% CI, 11.90-17.40] and 8.00 [95% CI, 6.63-9.37] per 100,000 person-years for men and women aged 80-84 years, respectively). The incidence rate of CRAO increased exponentially with age until the 9th decade of life.

CONCLUSIONS

To our knowledge, this is the first nationwide epidemiologic study of CRAO in individuals of all ages. The incidence rate of CRAO in Korea increased exponentially with increasing age and was highest among those aged 80 to 84 years. Moreover, the incidence rate in men was 1.47 times higher than that in women.

Risk factors for retinal arteriolar emboli in coronary artery disease

This study determined the prevalence of retinal arteriolar emboli risk factors in 148 patients (86 males) diagnosed with coronary artery disease who required coronary artery bypass graft surgery (mean +/- SD age 59.1 +/- 12.9 years). The prevalence of smoking was 50.7%, hypertension was 49.3%, diabetes mellitus was 27.0% and obesity was 31.1%. Retinal arteriolar emboli were detected using binocular indirect ophthalmoscopy of both eyes. They were found in 10 patients (6.8%) and identified as the cholesterol type. Patients were divided according to their baseline low-density lipoprotein cholesterol (LDL-C) serum level; retinal arteriolar emboli were significantly more frequent in patients with LDL-C levels > 100 mg/dl. These results demonstrate that the prevalence of hypercholesterolaemia and high LDL-C were increased in patients with retinal arteriolar emboli. Identification and treatment of modifiable risk factors, such as high LDL-C and hypercholesterolaemia, might be beneficial in these individuals.

Prevalence and risk factors of retinal arteriolar emboli: the Singapore Malay Eye Study

PURPOSE

To examine the prevalence and risk factors of retinal arteriolar emboli, a risk predictor of stroke, in an Asian population.

DESIGN

Population-based cross-sectional study.

METHODS

Retinal emboli were ascertained from retinal photographs obtained from both eyes of 3,265 Asian Malays, aged 40 to 80 years, according to a standardized protocol. Risk factors were assessed from detailed standardized interviews, clinical examinations, and laboratory investigations.

RESULTS

The overall prevalence of retinal emboli was 0.6% (95% confidence interval [CI], 0.58 to 0.62). A finding of retinal emboli was strongly associated with increasing age (P = .005, for trend), but age-stratified prevalence rates were still lower than those reported from previous population-based studies of White persons. After adjusting for age and gender, the presence of retinal emboli was associated with cigarette smoking (odds ratio [OR], 5.96; 95% CI, 1.75 to 20.32), elevated total cholesterol (OR, 5.21; 95% CI, 1.93 to 12.82), low-density lipoprotein cholesterol (OR, 2.98; 95% CI, 1.20 to 7.39), and self-reported history of angina (OR, 5.67; 95% CI, 1.62 to 19.91). These associations remained significant in multivariate analysis with additional adjustment for other risk factors.

CONCLUSIONS

Retinal emboli are less common in Asians than in similarly aged White persons, but are associated with similar cardiovascular risk factors.