Retinal Vein Occlusion in a Multi-Ethnic Asian Population: The Singapore Epidemiology of Eye Disease Study.

PURPOSE: To describe the prevalence of retinal vein occlusion (RVO) and its risk factors in a multi-ethnic Asian population. METHODS: This population-based study of 10,033 participants (75.7% response rate) included Chinese, Indian and Malay persons aged 40 years and older. A comprehensive ophthalmic examination, standardized interviews and laboratory blood tests were performed. Digital fundus photographs were assessed for presence of RVO following the definitions used in the Blue Mountains Eye Study. Regression analysis models were constructed to study the relationship between ocular and systemic factors and RVO. Age-specific prevalence rates of RVO were applied to project the number of people affected in Asia from 2013 to 2040. RESULTS: The overall crude prevalence of RVO was 0.72% (n = 71; 95% confidence interval, CI, 0.54-0.87%). The crude prevalence of RVO was similar in Chinese, Indian and Malay participants (p = 0.865). In multivariable regression models, significant risk factors of RVO included increased age (odds ratio, OR, 1.03, 95% CI 1.01-1.06), hypertension (OR 3.65, 95% CI 1.61-8.31), increased serum creatinine (OR 1.04, 95% CI 1.01-1.06, per 10 mmol/L increase), history of heart attack (OR 2.25, 95% CI 1.11-4.54) and increased total cholesterol (OR 1.31, 95% CI 1.07-1.59, per 1 mmol/L increase). None of the ocular parameters were associated with RVO. RVO is estimated to affect up to 16 and 21 million people in Asia by 2020 and 2040, respectively. CONCLUSION: RVO was detected in 0.72% of a multi-ethnic Asian population aged 40-80 years in Singapore. The significant systemic risk factors of RVO are consistent with studies in white populations.

Incident retinal vein occlusions and estimated cerebrospinal fluid pressure. The Beijing Eye Study.

PURPOSE: To examine whether the incidence of retinal vein occlusions (RVOs) is associated with estimated cerebrospinal fluid pressure (CSFP). METHODS: The population-based Beijing Eye Study, which included 4439 subjects (age: 40 + years) in 2001, was repeated in 2011 with 2695 subjects participating (66.4% of the survivors). Fundus photographs were examined for the new development of RVOs, differentiated into central RVOs (CRVOs) and branch RVOs (BRVOs). CSFP was calculated as CSFP [mmHg] = 0.44 × Body Mass Index [kg/m(2) ] + 0.16 × Diastolic Blood Pressure [mmHg]-0.18 × Age[Years]. RESULTS: Incident BRVOs were detected in 50 eyes and incident CRVOs in 8 eyes. BRVOs were located at arterio-venous crossings in 39 eyes. In multivariate analysis, a higher estimated CSFP was associated with a higher incidence of CRVOs (p = 0.004; standardized coefficient beta: 0.06; regression coefficient B: 5.35; 95% confidence interval (CI):1.73, 8.96) after adjusting for urban region (p < 0.001; beta: -0.52; B: -3.93; 95% CI: -4.29, -3.57), higher educational level (p = 0.001; beta: 0.13; B: 0.44; 95% CI: 0.28, 0.60), higher blood concentrations of triglycerides (p < 0.001; beta: 0.08; B: 0.11; 95% CI: 0.05, 0.16) and higher intraocular pressure (p < 0.001; beta: 0.16; B:0.21; 95% CI: 0.16, 0.27). As a corollary, a higher incidence of RVOs as a whole, as well as a higher incidence of CRVOs combined with a higher incidence of BRVOs originating at the optic nerve head, both were significantly associated with higher estimated CSFP (p = 0.002; odds ratio (OR): 1.15; 95% CI: 1.05, 1.25; and p = 0.037; OR: 1.17; 95% CI: 1.01, 1.35, respectively) after adjusting for older age. CONCLUSIONS: A higher estimated CSFP was associated with a higher incidence of RVOs originating at the optic nerve head (i.e. CRVOs, hemi-central RVOs and BRVOs originating at the optic nerve head), and vice versa, a higher incidence of RVOs was associated with a higher estimated CSFP. It suggested an influence of higher estimated CSFP on higher central retinal vein pressure.

Branch retinal vein occlusion and optic nerve head topographic parameters: the Singapore Indian eye study.

AIM: To examine the association between branch retinal vein occlusion (BRVO) and quantitative optic disc topographic parameters. METHODS: The Singapore Indian Eye Study (SINDI) is a population-based study of 3400 Singapore Indians aged 40+ years. BRVO was defined and graded from retinal photographs. Optic disc parameters were quantified using the Heidelberg Retinal Tomograph III (HRT III). Associations were evaluated for individual eyes; the generalised estimating equation was used to account for correlation between fellow eyes. RESULTS: 6173 eyes (comprising 19 BRVO) had gradable retinal photographs and HRT images. After controlling for age, gender, and systemic (hypertension, diabetes, myocardial infarction) and ocular factors (intraocular pressure, glaucoma, central corneal thickness, axial length, previous laser photocoagulation), BRVO was associated with larger optic disc area (OR highest vs lowest tertile, 4.70; 95% CI 1.00 to 22.01; p=0.036), larger cup area (OR highest vs lowest tertile, 4.80; 95% CI 1.03 to 22.35; p=0.029) and larger cup-disc area ratio (OR highest vs lowest tertile, 4.44; 95% CI 0.95 to 20.66; p=0.037). After excluding glaucoma eyes, BRVO remained significantly associated with these parameters (p=0.027, p=0.018, p=0.024, respectively). CONCLUSIONS: Quantitative optic disc parameters (optic cup and disc area) are associated with BRVO, even in non-glaucomatous eyes. Optic nerve head morphology may play a role in BRVO pathogenesis.

Nine-year incidence and risk factors for retinal vein occlusion in a general Japanese population: the Hisayama Study.

PURPOSE: To estimate the long-term cumulative incidence and risk factors for retinal vein occlusion (RVO) in a population-based cohort study of Japanese. METHODS: In 1998, a total of 1775 individuals aged 40 years or older underwent a baseline eye examination. Of those, 1369 subjects (77.1%) took part in the follow-up eye examination in 2007 and were enrolled in the present study. Each participant underwent a comprehensive examination. The diagnosis of RVO, including branch (BRVO) and central RVO (CRVO), was determined by grading color fundus photographs. Logistic regression analysis was performed to determine risk factors for RVO. RESULTS: The 9-year cumulative incidence of RVO was 3.0% (2.7% for BRVO and 0.3% for CRVO). The age-specific cumulative incidence of RVO significantly increased with age (P for trend = 0.03). After adjusting for age and sex, higher diastolic blood pressure and chronic kidney disease (CKD) were significantly associated with RVO. In multivariate analysis, higher diastolic blood pressure (per 10 mm Hg) (odds ratio [OR], 1.51; 95% confidence interval [CI], 1.14 to 2.01) and CKD (OR, 2.23; 95% CI, 1.02 to 4.89) remained independently significant risk factors for RVO. In stratified analysis, the risk of RVO was higher in subjects with CKD than that in subjects without CKD in both the nonhypertension and the hypertension groups. CONCLUSIONS: These findings suggest that the incidence of RVO is higher in Japanese than that in other Asians and Caucasians, and that higher blood pressure and CKD are independent risk factors for RVO in the Japanese.

Retinal vein occlusion and angle closure: a retrospective case series.

PURPOSE: To describe a series of patients who have sustained a retinal vein occlusion (RVO) and also have primary angle-closure (PAC). METHODS: We retrospectively ascertained demographic characteristics (age, sex, and ethnicity), presentation (history and examination findings), investigations undertaken, features of angle-closure or occludable angles (symptoms, method of diagnosis, and treatment), and outcome (intraocular pressure (IOP) and visual acuity). RESULTS: Nineteen subjects were included in the study, comprising 9 males and 10 females, with an average age of 69 years (range 44 to 86 y). The ethnicity of the group was diverse. The mode of presentation in 75% of patients was that RVO and PAC were diagnosed at the same clinical visit. In the remaining 25% of cases, the diagnosis of PAC was delayed and ranged from 4 months to 9 years after the RVO. Increased IOP on dilation was found to have raised the suspicion of PAC in some patients, either at the time of first presentation with RVO or at a later date during follow-up for the RVO, leading to gonioscopy and a diagnosis of PAC. In 1 patient, an observed asymmetrical cup-to-disc ratio led to gonioscopy and diagnosis of PAC. Fourteen patients sustained a central retinal vein occlusion (CRVO), 2 subjects sustained a hemicentral retinal vein occlusion (HRVO), and 3 patients had a branch retinal vein occlusion. In the vast majority of cases in this series (18/19), no additional systemic risk factors were identified during follow-up apart from those that were present before the RVO. The diagnosis of PAC was made in all patients on the basis of static and dynamic gonioscopy. None of these patients had experienced any symptoms of acute or intermittent IOP rises as a consequence of angle-closure. Fifteen patients were diagnosed with PAC glaucoma in 1 or both eyes. Sixteen subjects (84.0%) underwent peripheral laser iridotomies and 7 patients (37.0%) had lens extraction to improve angle configuration. CONCLUSION: Our study supports the belief that angle-closure may be associated with retinal vein occlusions, and should be borne in mind and excluded when investigating the patient with RVO, especially CRVO/HRVO. We suggest that gonioscopy should be done in all patients presenting with RVO.

Prevalence and systemic risk factors for retinal vein occlusion in a general Japanese population: the Hisayama study.

PURPOSE: To examine the prevalence of retinal vein occlusion (RVO) and its systemic relevant factors in a general Japanese population aged 40 years or older. METHODS: In 1998, 1775 Hisayama residents consented to participate in the study. Each participant underwent a comprehensive examination that included ophthalmic testing. RVO was determined by grading color fundus photographs. Logistic regression analysis was performed to determine risk factors for RVO. RESULTS: Of the 1775 subjects examined, 38 had RVO. The prevalence of RVO was 2.1% (2.0% for branch RVO and 0.2% for central RVO). After adjustment for age and sex, it was found that systolic and diastolic blood pressures, hypertension, and hematocrit were significantly associated with RVO. In multivariate analysis, age (per 10 years; odds ratio [OR], 1.47; 95% confidence interval [CI], 1.04-2.08), hypertension (OR, 4.25; 95% CI, 1.82-9.94), and hematocrit (per 10%; OR, 3.09; 95% CI, 1.10-1.22) remained independently significant risk factors for RVO. Both high-normal blood pressure and hypertension were significantly associated with RVO. Furthermore, compared with normotensive subjects without high hematocrit, the likelihood of RVO was markedly high in subjects having both high blood pressure and high hematocrit (age- and sex-adjusted OR, 36.0; 95% CI, 4.43-292). CONCLUSIONS: The findings suggest that the prevalence of RVO is higher in the Japanese than in other Asians or Caucasians and that older age, higher hematocrit, and both hypertension and high-normal blood pressure are significant risk factors for RVO in the Japanese.

Prevalence and risk factors of retinal vein occlusion in an Asian population.

AIM: To describe the prevalence and risk factors of retinal vein occlusion (RVO) in an Asian population. METHODS: The Singapore Malay Eye Study is a population-based, cross-sectional study of 3280 (78.7%) Malay adults (aged 40-80 years) living in Singapore. All participants underwent retinal photography, standardised interview, clinical examinations and laboratory investigations. RVO (central or branch) was graded based on the Blue Mountains Eye Study (BMES) protocol from retinal photographs. RESULTS: The overall prevalence of RVO was 0.7% (n = 22) (95% CI 0.4 to 1.0) (18 branch and five central RVO cases). There was no significant gender difference in RVO prevalence. RVO was associated with higher systolic blood pressure (age-adjusted odds ratio (OR) per SD increase 1.54, CI 1.02 to 2.31), ocular perfusion pressure (OR per SD increase 1.49, CI 1.03 to 2.16), a history of angina (OR 5.18, CI 1.49 to 18.0) and heart attack (OR 4.26, CI 1.47 to 12.3), and higher total cholesterol (OR per SD increase 1.55, CI 1.07 to 2.24) and LDL (OR per SD increase 1.47, CI 1.02 to 2.12) cholesterol levels. CONCLUSIONS: The prevalence of RVO in this Asian population was lower than Caucasians in the BMES, although the systemic associations of RVO were largely similar to BMES and other studies.

Traditional and novel cardiovascular risk factors for retinal vein occlusion: the multiethnic study of atherosclerosis.

PURPOSE: To describe the prevalence of retinal vein occlusion (RVO) and its association with cardiovascular, inflammatory, and hematologic risk factors in a multiethnic cohort. METHODS: This was a population-based, cross-sectional study of 6147 participants (whites, blacks, Hispanics, Chinese) from six U.S. communities. RVO was defined from retinal photographs taken from both eyes according to a standardized protocol. Risk factors were assessed from interviews, examinations, and laboratory and radiologic investigations. RESULTS: The prevalence of RVO was 1.1% (0.9% for branch RVO and 0.2% for central RVO) and was similar across different ethnic groups: 0.9% in whites, 1.2% in blacks, 1.2% in Hispanics, and 1.1% in Chinese (P = 0.76). Independent risk factors associated with RVO were hypertension (odds ratio [OR], 2.06; 95% confidence interval [CI], 1.18-3.59), older age (OR, 1.34; 95% CI, 1.00-1.81, per decade increase), less education (OR, 4.08; 95% CI, 2.20-7.54), hypertriglyceridemia (OR, 1.98; 95% CI, 1.10-3.56), renal dysfunction (OR, 1.85; 95% CI, 1.01-3.39), and the presence of retinal arteriovenous nicking (OR, 4.01; 95% CI, 2.06-7.81) and focal arteriolar narrowing (OR, 4.38; 95% CI, 1.44-13.34). RVO was not significantly associated with direct measures of subclinical atherosclerosis (e.g., carotid intima media thickness and coronary artery calcium scores) or markers of inflammation (e.g., C reactive protein, interleukin-6) and endothelial dysfunction (e.g., soluble intercellular adhesion molecule-1) or coagulation (e.g., D-dimer). CONCLUSIONS: The prevalence of RVO is similar across different racial/ethnic groups. In the general population, RVO is associated with hypertension, dyslipidemia, and renal dysfunction, but not with atherosclerotic disease, systemic inflammation, and hematologic abnormalities.

Hyperhomocysteinemia and low methionine stress are risk factors for central retinal venous occlusion in an Indian population.

PURPOSE: The underlying cause of disturbed homocysteine metabolism is incompletely understood in young persons with central retinal vein occlusion (CRVO) with mild hyperhomocysteinemia (HHcys) and no other systemic disease in India. A 2-year prospective study was undertaken to determine whether HHcys is a risk factor for CRVO in an Indian population. METHOD: The prevalence of fasting HHcys was evaluated in a consecutive series of 29 patients with CRVO (mean age, 30 +/- 6 years) along with 57 age- and sex-matched control subjects (healthy subjects, mean age 27 +/- 5 years). Strict inclusion and exclusion criteria were used. Plasma levels of homocysteine (Hcys), methionine, cysteine, glutathione, B(12), and folate were measured. Multivariate logistic regression analysis was performed to determine the risk factors for CRVO. RESULT: Fifteen of 29 patients with CRVO (51.72%) exhibited HHcys (>15 muM). The mean Hcys level was significantly elevated in the patients with CRVO (19.1 +/- 13.1 muM) compared with that in the healthy control subjects (14.7 +/- 6.2 muM) with P = 0.04. The increased Hcys levels in CRVO cases was associated with decreased methionine (P = 0.052) and decreased B(12) (P = 0.001). A multivariate logistic regression analysis revealed an odds ratio of 1.9 (95% CI = 0.50-7.16) for Hcys and 15.9 for methionine (95%CI = 1.50-169.62; P = 0.022). CONCLUSION: Elevated Hcys and low methionine were risk factors for CRVO in an Indian population.

Hyperhomocysteinemia and low plasma folate as risk factors for central retinal vein occlusion: a case-control study in a Chinese population.

PURPOSE: To determine whether hyperhomocysteinemia and low plasma folate are risk factors for central retinal vein occlusion (CRVO) in the Chinese population. METHODS: A matched case-control study was conducted between July 2004 and May 2005. The study cohort consisted of 64 individuals that had been diagnosed to have CRVO and 64 normal controls (matched for age, gender, hypertension, smoking and drinking habits). None of the cases or controls had a history of diabetes, glaucoma, medication or any other vascular events that might minimize the influence on plasma homocysteine levels. A cross-sectional analysis among the 64 cases was performed to compare the prevalence of hyperhomocysteinemia and low plasma folate among subjects with and without ischemia and subjects with age above 45 and below 45 years. Plasma homocysteine level was measured by means of high-performance liquid chromatography and plasma folate concentration by radioimmunoassay. RESULTS: The CRVO patients had a significantly higher homocysteine level (13.83+/-1.71 micromol/l) than the normal controls (8.05+/-0.58 micromol/l; p=0.003). The plasma folate levels were significantly lower in CRVO patients than in controls (5.62+/-0.39 ng/dl vs 7.23+/-0.60 ng/dl; p=0.032). A 1 micromol/l increase of plasma homocysteine level was associated with an odds ratio of 1.368. Hyperhomocysteinemia was defined as a homocysteine level of >14.97 micromol/l and was seen in 11 patients in the ischemic group, significantly more often than in the non-ischemic group (5 patients; p=0.030). CONCLUSIONS: The results suggest that hyperhomocysteinemia and low plasma folate are independent risk factors for CRVO and are associated with the development of CRVO in the Chinese population.

Branch retinal vein occlusion in a Japanese patient with neurofibromatosis 1.

BACKGROUND: To report an Asian patient with branch retinal vein occlusion secondary to neurofibromatosis 1. CASE: A 64-year-old woman presented with a loss of vision in her right eye of 9-month duration. A diagnosis of neurofibromatosis 1 was made. A general medical examination showed no abnormalities except the signs of neurofibromatosis 1. OBSERVATIONS: Fundus examination of the right eye revealed irregularities of the venous caliber, partial sheathing of the corresponding vein and macular edema. Multiple dilated and tortuous collateral channels and an arteriovenous communication bridged the perfused and nonperfused retina. Fundus examination of the left eye showed a tortuous vein in the temporal region of the fovea. Fluorescein angiography of the right eye confirmed delayed filling in a superotemporal artery and in the corresponding vein. The temporal region of the fovea had large areas of capillary loss. The collaterals were tortuous and mimicked a neovascularization. Fluorescein angiography of the left eye confirmed that the vein in the temporal part of the fovea was tortuous and not leaking. A diagnosis of branch retinal vein occlusion of the superotemporal vein was made. CONCLUSIONS: Neurofibromatosis 1 should be considered in the differential diagnosis of retinal vascular occlusive disease without other risk factors.

A comparative study of branch retinal vein occlusion and central vein occlusion amongst Malaysian patients.

A retrospective study of 95 patients with retinal vein occlusion was carried out to determine the clinical presentation and pattern of distribution in the local Malaysian population. There was no significant difference found in its distribution with regards to sex. In comparing branch retinal vein occlusion with central retinal vein occlusion, no significant differences were found in its racial distribution. Branch retinal vein occlusion occurred more commonly among the older patients whereas the converse is true for central retinal vein occlusion. Reduced vision represents the commonest mode of presentation. Hypertension, diabetes mellitus, hyperlipidaemia and haematological disorders are important associated systemic conditions.

Risk factors for retinal vein occlusions. A case-control study.

The authors conducted a case-control study of risk factors for retinal vein occlusions using 87 patients with vein occlusions, chosen randomly from photographic files from their institution between 1985 and 1990, and a control group of 85 subjects 38 years of age (the youngest individual in the vein occlusion group) or older, who were randomly selected from the records of two general ophthalmologists in the authors' department. Certain risk factors for retinal vein occlusion were highly significant when subjects with retinal vein occlusion were compared with the control group. These risk factors included systemic hypertension (odds ratio [OR], 3.86; 95% confidence interval [Cl], 2.08 to 7.16), open-angle glaucoma (OR, 2.89; 95% Cl, 1.38 to 6.05), and male sex (OR, 2.61; 95% Cl, 1.43 to 4.79). Race, presence of diabetes mellitus, history of coronary artery disease or stroke, and family history of diabetes, glaucoma, coronary artery disease, or stroke were not significant risk factors in the population studied. Logistic analysis of the risk factors showed no interactions. Risk factors for branch retinal vein occlusion and central retinal vein occlusion were identical.

Diabetes mellitus and retinal vein occlusion in patients of Asian, west Indian and white European origin.

The incidence of retinal vein occlusion (RVO) is known to be related to several cardiovascular risk factors including diabetes mellitus, hypertension and hyperlipidaemia. We have assessed the prevalence of these risk factors in Caucasian (N = 536, mean age = 65.21 years), West Indians (N = 24, mean age = 57.3 years) and Asian (N = 28, mean age = 51.4 years) patients presenting with RVO. We found no significant differences between the three groups in the distribution of hyperlipidaemia, but diabetes mellitus was more common amongst both the Asians and W. Indians (10% v 29% and 38%, p < 0.01 and p < 0.001). Hypertension was also more common in both the Asians and the West Indians (59% v 64% and 83% m p < 0.001 and p < 0.0001). The Asians and West Indians presenting with RVO were significantly younger and had significantly higher body mass index than their Caucasian counterparts (Ethnic origin, BMI, mean age: Asian, 28.1 +/- 4.3, 51.5 +/- 12.3 years; West indian: 30.2 +/- 7.7, 57.3 + 10 years; White: 24.8 +/- 4.2, 65.2 +/- 11.4 years). In this study RVO occurred at a younger age in Asians and West Indians, and was associated with a greater prevalence of diabetes mellitus and hypertension. The prevalence of hyperlipidaemia was no different in the three groups.

Factors associated with retinal-vein occlusion in Hispanics.

Sixty-eight foreign-born Hispanic patients with angiography-proven retinal-vein occlusion (RVO) and 50 age-, sex-, and race-matched controls were evaluated for systemic disease. Thirty of the RVO patients had central retinal-vein occlusion, and 38 had branch retinal-vein occlusion. Hypertension, the most commonly associated factor, was present in 66.2% of the RVO patients in contrast to 18% of the controls (P less than .001). Other factors which were more common in the RVO population included open-angle glaucoma (19.1% vs 8%), diabetes mellitus (16.2% vs 12%), and atherosclerotic heart disease (14.7% vs 10%); these, however, were not statistically significant (P greater than .05). Hyperlipidemia was present in 12% of the controls and 10.3% of the RVO group (P greater than .50). This is in direct contrast to reports of nonHispanic populations where hyperlipidemia has been reported to be present in up to 60% of RVO patients.