With the intention of developing a more targeted control strategy for retinal vein occlusion (RVO) in East Asian populations, a meta-analysis was conducted to evaluate the risk factors associated with RVO in this region.

PubMed, Web of Science, Cochrane Library, CNKI, Wanfang and VIP databases were searched for studies that reported risk factors of RVO in East Asia, published from the establishment of the database to May 2024. To further filter the articles, Newcastle-Ottawa Scale (NOS) evaluation method was utilized to assess the quality of selected articles. After valid data were extracted, Meta-analysis was performed by Review Manager software.

A total of 21 literatures were included, including 27561 cases in the RVO group (Case group) and 514578 cases in the non-retinal vein occlusion (NRVO) group (Control group). Results of meta-analysis showed that chronic kidney disease [odds ratio (OR)=4.14, 95% confidence interval (CI): (1.86%, 9.24%)], hypertension [OR=4.11, 95% CI: (3.09%, 5.48%)], hyperlipidemia [OR=3.45, 95%CI: (2.32%, 5.12%)], diabetes mellitus [OR=3.00, 95%CI: (1.88%, 4.80%)], homocysteine [OR=0.87, 95%CI: (0.59%, 1.15%)], have statistically significant differences between the RVO group and the NRVO group(P<0.05).

The occurrence of RVO is closely related to its risk factors, such as chronic kidney disease, hypertension, hyperlipidemia, diabetes mellitus and high homocysteine. In the process of diagnosis and treatment of RVO, doctors should focus on the above risk factors to prevent the occurrence of the disease.

To assess the association between use of sodium-glucose cotransporter 2 (SGLT2) inhibitors and retinal vein occlusion (RVO) using data from the National Health Insurance Service in South Korea.

We used an active comparator, new user design, and nationwide data from 2014 to 2017. Based on a 1:1 propensity score match, we included 47,369 new users of SGLT2 inhibitors and 47,369 users of other glucose-lowering drugs (oGLDs). In the matched sample, we used the Cox proportional hazards model to estimate hazard ratios (HRs) with 95% CIs for developing RVO. Based on the main outcome, exploratory subgroup analyses were undertaken.

During a follow-up of 2.57 years, the incidence rate of RVO was 2.19 and 1.79 per 1,000 person-years in patients treated with SGLT2 inhibitors and oGLDs, respectively. The new use of SGLT2 inhibitors was associated with an increased risk of RVO compared with oGLD use (HR 1.264 [95% CI 1.056, 1.513]). In the subgroup analyses, a significant interaction with SGLT2 inhibitors was observed for age and estimated glomerular filtration rate (eGFR); the HR for RVO was higher in patients aged ≥60 years and those with eGFR <60 mL/min/1.73 m2 than in others.

In a matched cohort study, we found that SGLT2 inhibitors were associated with a significantly increased risk of RVO. Older patients and those with chronic kidney disease were at higher risk for RVO.

Branch retinal vein occlusion (BRVO) is one of the most commonly occurring retinal vascular abnormalities. The most common cause of visual loss in people with BRVO is macular oedema (MO). Grid or focal laser photocoagulation has been shown to reduce the risk of visual loss. Limitations to this treatment exist, however, and newer modalities may have equal or improved efficacy. Antiangiogenic therapy with anti-vascular endothelial growth factor (anti-VEGF) has recently been used successfully to treat MO resulting from a variety of causes.

To investigate the efficacy and gather evidence from randomised controlled trials (RCTs) on the potential harms of anti-vascular endothelial growth factor (VEGF) agents for the treatment of macular oedema (MO) secondary to branch retinal vein occlusion (BRVO).

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2019, Issue 6); MEDLINE Ovid; Embase Ovid; the ISRCTN registry; ClinicalTrials.gov; and the WHO ICTRP. The date of the last search was 12 June 2019.

We included randomised controlled trials (RCTs) investigating BRVO. Eligible trials had to have at least six months' follow-up where anti-VEGF treatment was compared with another treatment, no treatment, or placebo. We excluded trials where combination treatments (anti-VEGF plus other treatments) were used; and trials that investigated the dose and duration of treatment without a comparison group (other treatment/no treatment/sham).

Two review authors independently extracted the data using standard methodological procedures expected by Cochrane. The primary outcome was the proportion of participants with an improvement from baseline in best-corrected visual acuity of greater than or equal to 15 letters (3 lines) on the Early Treatment in Diabetic Retinopathy Study (ETDRS) Chart at six months and 12 months of follow-up. The secondary outcomes were the proportion of participants who lost greater than or equal to 15 ETDRS letters (3 lines) and the mean visual acuity (VA) change at six and 12 months, as well as the change in central retinal thickness (CRT) on optical coherence tomography from baseline at six and 12 months. We also collected data on adverse events and quality of life (QoL).

We found eight RCTs of 1631 participants that met the inclusion criteria after independent and duplicate review of the search results. These studies took place in Europe, North America, Eastern Mediterranean region and East Asia. Included participants were adults aged 18 or over with VA of 20/40 or worse. Studies varied by duration of disease but permitted previously treated eyes as long as there was sufficient treatment-free interval. All anti-VEGF agents (bevacizumab, ranibizumab and aflibercept) and steroids (triamcinolone and dexamethasone) were included. Overall, we judged the studies to be at moderate or unclear risk of bias. Four of the eight studies did not mask participants or outcome assessors, or both. One trial compared anti-VEGF to sham. At six months, eyes receiving anti-VEGF were significantly more likely to have a gain of 15 or more ETDRS letters (risk ratio (RR) 1.72, 95% confidence interval (CI) 1.19 to 2.49; 283 participants; moderate-certainty evidence). Mean VA was better in the anti-VEGF group at six months compared with control (mean difference (MD) 7.50 letters, 95% CI 5.29 to 9.71; 282 participants; moderate-certainty evidence). Anti-VEGF also proved more effective at reducing CRT at six months (MD -57.50 microns, 95% CI -108.63 to -6.37; 281 participants; lower CRT is better; moderate-certainty evidence). There was only very low-certainty evidence on adverse effects. There were no reports of endophthalmitis. Mean change in QoL (measured using the National Eye Institute Visual Functioning Questionnaire VFQ-25) was better in people treated with anti-VEGF compared with people treated with sham (MD 7.6 higher score, 95% CI 4.3 to 10.9; 281 participants; moderate-certainty evidence). Three RCTs compared anti-VEGF with macular laser (total participants = 473). The proportion of eyes gaining 15 or more letters was greater in the anti-VEGF group at six months (RR 2.09, 95% CI 1.44 to 3.05; 2 studies, 201 participants; moderate-certainty evidence). Mean VA in the anti-VEGF groups was better than the laser groups at six months (MD 9.63 letters, 95% CI 7.23 to 12.03; 3 studies, 473 participants; moderate-certainty evidence). There was a greater reduction in CRT in the anti-VEGF group compared with the laser group at six months (MD -147.47 microns, 95% CI -200.19 to -94.75; 2 studies, 201 participants; moderate-certainty evidence). There was only very low-certainty evidence on adverse events. There were no reports of endophthalmitis. QoL outcomes were not reported. Four studies compared anti-VEGF with intravitreal steroid (875 participants). The proportion of eyes gaining 15 or more ETDRS letters was greater in the anti-VEGF group at six months (RR 1.67, 95% CI 1.33 to 2.10; 2 studies, 330 participants; high-certainty evidence) and 12 months (RR 1.76, 95% CI 1.36 to 2.28; 1 study, 307 participants; high-certainty evidence). Mean VA was better in the anti-VEGF group at six months (MD 8.22 letters, 95% CI 5.69 to 10.76; 2 studies, 330 participants; high-certainty evidence) and 12 months (MD 9.15 letters, 95% CI 6.32 to 11.97; 2 studies, 343 participants; high-certainty evidence). Mean CRT also showed a greater reduction in the anti-VEGF arm at 12 months compared with intravitreal steroid (MD -26.92 microns, 95% CI -65.88 to 12.04; 2 studies, 343 participants; moderate-certainty evidence). People receiving anti-VEGF showed a greater improvement in QoL at 12 months compared to those receiving steroid (MD 3.10, 95% CI 0.22 to 5.98; 1 study, 307 participants; moderate-certainty evidence). Moderate-certainty evidence suggested increased risk of cataract and raised IOP with steroids. There was only very low-certainty evidence on APTC events. No cases of endophthalmitis were observed.

The available RCT evidence suggests that treatment of MO secondary to BRVO with anti-VEGF improves visual and anatomical outcomes at six and 12 months.

We performed this meta-analysis to assess the correlation of retinal vein occlusion (RVO) and chronic kidney disease (CKD).

We searched PubMed, Embase, Web of Science and Cochrane Library for population-based studies reporting the CKD as associated factor to RVO, central retinal vein occlusion (CRVO) or branch retinal vein occlusion (BRVO). Then we pooled the data for analysis.

After screening potential literature, 12 eligible studies with 23,656,214 individuals were finally included in quantitative synthesis. The pooled prevalence (95% confidence interval [CI]) of CKD in RVO group was 10.9% (95% CI: 6.6%, 15.1%). The pooled prevalence of any RVO in end stage renal disease (ESRD) group was 1.8% (95% CI: 1.6%, 2.1%). The prevalence of CKD was significantly higher in subjects diagnosed with RVO than non-RVO participants (odds ratio [OR]: 3.30; 95% CI: 2.28, 4.76; p < 0.001). CRVO subjects had a higher prevalence of CKD than BRVO patients (OR: 2.17; 95% CI: 1.28, 4.66; p = 0.004). In a similar manner, compared to non-ESRD subjects, ESRD patients had significantly higher prevalence of RVO (OR: 2.19; 95% CI: 1.97, 2.43; p < 0.001), CRVO (OR: 2.61; 95% CI: 2.17, 3.15; p < 0.001) and BRVO (OR: 2.01; 95% CI: 1.76, 2.30; p < 0.001).

The prevalence of CKD increases in RVO patients, especially in CRVO. And in turn, the prevalence of RVO also increases in ESRD patients. The data support a correlation of RVO and CKD.

To determine the proportion of people with type 2 diabetes mellitus (T2DM) attending large eye care facilities across India who have retinal vascular occlusion (RVO).

A 6-month descriptive, multicenter, observational hospital-based study of people was being presented to the 14 eye care facilities in India. The retina-specific component of comprehensive eye examination included stereoscopic biomicroscopy, binocular indirect ophthalmoscopy, and fundus fluorescein angiography, and optical coherence tomography was also available when needed. Data recording of the duration of diabetes, hypertension (HTN), stroke, and other variables was obtained from the medical history. The statistical analysis included frequencies, mean, and standard deviations for continuous variables. Odds ratio (OR) and multivariate analysis were undertaken to assess the associations between risk factors and RVO.

The study recruited 11,182 consecutive patients (22,364 eyes) with T2DM. About 59.0% (n = 6697) were male. The mean age was 58.2 ± 10.6 years. In this cohort, RVO was detected in 3.4% (n = 380) of patients; 67.6% (n = 257) of them had branch retinal vein occlusion (BRVO) and the remaining 32.4% (n = 123) had central retinal vein occlusion (CRVO). The frequency of unilateral BRVO (n = 220, 85.6%) and unilateral CRVO (n = 106, 86.18%) was much common. Unilateral RVO was more frequent (n = 326, 85.8%) than bilateral diseases (n = 54, 14.2%) (χ2 = 126.95, P < 0.001). Ischemic CRVO was more common (n = 103, 73.6%) than nonischemic CRVO (n = 37, 26.4%). Macula-involving BRVO was found in 58.5% (n = 172) of cases, suggesting more than 50% of cases in RVO carries a risk of severe vision loss. The duration of diabetes apparently had no influence on the occurrence of RVO. On the multivariate analysis, a history of HTN [OR: 1.7; 95% confidence interval (CI): 1.3-2.1; P = 0.001) and stroke (OR: 5.1; 95% CI: 2.1-12.4; P < 0.001) was associated with RVO.

RVO is a frequent finding in people with T2DM. History of stroke carries the highest risk followed by HTN. The management of people with T2DM and RVO must also include comanagement of all associated systemic conditions.

In Australia, knowledge of the epidemiology of retinal vein occlusion remains scarce because of a paucity of recent population-based data. The National Eye Health Survey (2015-2016) provides an up-to-date estimate of the prevalence of retinal vein occlusion in non-Indigenous and Indigenous Australian adults.

To determine the prevalence and associations of retinal vein occlusion in a national sample of Indigenous and non-Indigenous Australian adults.

Population-based cross-sectional study.

A total of 3098 non-Indigenous Australians (aged 50-98 years) and 1738 Indigenous Australians (aged 40-92 years) living in 30 randomly selected sites, stratified by remoteness.

Retinal vein occlusions were graded from retinal photographs using standardized protocols and recorded as central retinal vein occlusion or branch retinal vein occlusion.

Prevalence of retinal vein occlusion.

In the non-Indigenous population, the sampling weight adjusted prevalence of any retinal vein occlusion was 0.96% (95% confidence interval: 0.59, 1.6), with branch retinal vein occlusion observed in 0.72% (95% confidence interval: 0.41, 1.2) and central retinal vein occlusion in 0.24% (95% confidence interval: 0.13, 0.47). Any retinal vein occlusion was found in 0.91% (95% confidence interval: 0.47, 1.7) of Indigenous Australians aged 40 years and over, with branch retinal vein occlusion observed in 0.83% (95% confidence interval: 0.40, 1.7) and central retinal vein occlusion in 0.07% (95% confidence interval: 0.02, 0.32). Older age (odds ratio = 1.64 per 10 years, P = 0.006) and the presence of self-reported diabetes (odds ratio = 3.24, P = 0.006) were associated with any retinal vein occlusion after multivariable adjustments. Retinal vein occlusion was attributed as the cause of monocular vision loss (<6/12) in seven (0.25%) non-Indigenous and six (0.36%) Indigenous participants.

These data suggest that retinal vein occlusion is relatively uncommon in the non-Indigenous Australians aged 50 years and over and Indigenous Australians aged 40 years and over. Similar to previous Australian and international reports, the prevalence of retinal vein occlusion rose sharply with age.

To determine the influence of diabetes and diabetes type on ocular outcomes following central retinal vein occlusion (CRVO).

Retrospective chart review of all patients evaluated over a 4-year period in a tertiary diabetes eye care center. Ophthalmic findings were recorded including visual acuity and the presence of retinal neovascularization at presentation, after 3-6 months, and at last follow-up.

The records of 19,648 patients (13,571 diabetic; 6077 nondiabetic) were reviewed. The prevalence of CRVO in diabetic patients (N=72) and nondiabetic patients (N=27) were 0.5 and 0.4%, respectively. Disc neovascularization (21.3 vs 0.0%, P=0.05) and panretinal photocoagulation (PRP) (48.7 vs 21.4%, P=0.01) were more common in diabetic patients compared with nondiabetic patients. Compared with type 2 diabetic patients, retinal neovascularization (28.6 vs 3.7%, P=0.004) and subsequent PRP (78.6 vs 41.9%, P=0.01) were more likely in type 1 patients. Optic nerve head collateral vessels (CVs) were observed less than half as often (21.4 vs 56.5%, P=0.04) in patients with type 1 diabetes. Presence of optic nerve head CVs at baseline was associated with less likelihood of PRP (14.3 vs 46.1%, P=0.03).

In this cohort, the rates of CRVO in diabetic and nondiabetic patients were similar to previously published population-based studies. Following CRVO, diabetic patients had higher rates of disc neovascularization and were more likely to require subsequent PRP than nondiabetic patients. As compared with CRVO patients with type 2 diabetes, patients with type 1 diabetes and CRVO had worse anatomic outcomes with substantially increased risks of retinal neovascularization and PRP; however, final visual acuity outcomes were similar.

Branch retinal vein occlusion (BRVO) is one of the most common occurring retinal vascular abnormalities. The pathogenesis of BRVO is thought to involve both retinal vein compression and damage to the vessel wall, possibly leading to thrombus formation at sites where retinal arterioles cross retinal veins. The most common cause of visual loss in patients with BRVO is macular oedema (MO). Grid or focal laser photocoagulation has been shown to reduce the risk of visual loss and improve visual acuity (VA) in up to two thirds of individuals with MO secondary to BRVO, however, limitations to this treatment exist and newer modalities have suggested equal or improved efficacy. Recently, antiangiogenic therapy with anti-vascular endothelial growth factor (anti-VEGF) has been used successfully to treat MO resulting from a variety of causes. As elevated intraocular levels of VEGF have been demonstrated in patients with retinal vein occlusions there is a strong basis for the hypothesis that anti-VEGF agents may be beneficial in the treatment of vascular leakage and MO.

To investigate the efficacy and safety of intravitreal anti-VEGF agents for preserving or improving vision in the treatment of MO secondary to BRVO.

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2012, Issue 7), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to August 2012), EMBASE (January 1980 to August 2012), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to August 2012, the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 7 August 2012 and the clinical trials registers on 10 September 2012.

We included randomised controlled trials (RCTs) and quasi-RCTS of at least six months duration where anti-VEGF treatment was compared with another treatment, no treatment, or placebo. We excluded trials where combination treatments (anti-VEGF plus other treatments) were used and trials that investigated the dose and duration of treatment without a comparison group (other treatment/no treatment/sham).

Two review authors independently extracted the data. The primary outcome was the proportion of participants with an improvement from baseline in best-corrected visual acuity (BCVA) of greater than or equal to 15 letters (3 lines) on the Early Treatment in Diabetic Retinopathy Study (ETDRS) Chart at six months and at 12 months of follow-up. The secondary outcomes we report are the proportion of participants who lost greater than or equal to 15 ETDRS letters (3 lines) and the mean VA change at six months and any additional follow-up intervals as well as the change in central retinal thickness on optical coherence tomography (OCT) from baseline and final reported follow-up, the number and type of complications, the number of additional interventions administered and any adverse outcomes. Where available, the cost benefit and quality of life data reported in the primary studies is presented.

We found one RCT and one quasi-RCT that met the inclusion criteria after independent and duplicate review of the search results. The studies used different anti-VEGF agents and different study groups which were not directly comparable.One multi-centre RCT (BRAVO) conducted in the USA randomised 397 individuals and compared monthly intravitreal ranibizumab (0.3 mg and 0.5 mg) injections with sham injection. The study only included individuals with non-ischaemic BRVO. Although repeated injections of ranibizumab appeared to have a favourable effect on the primary outcome, approximately 50% of the ranibizumab 0.3 mg group and 45% of the ranibizumab 0.5 mg group received rescue laser treatment which may have an important effect on the primary outcome. In addition, during the six-month observation period 93.5% of individuals in the sham group received intravitreal ranibizumab (0.5 mg). This cross-over design limits the ability to compare the long-term impact of ranibizumab versus a pure control group.The second trial was a small study (n = 30) from Italy with limitations in study design that reported a benefit of as-required intravitreal bevacizumab (1.25 mg) over laser photocoagulation in MO secondary to BRVO. We present the evidence from these trials and other interventional case series.

The available RCT evidence suggests that repeated treatment of non-ischaemic MO secondary to BRVO with the anti-VEGF agent ranibizumab may improve clinical and visual outcomes at six and 12 months. However, the frequency of re-treatment has not yet been determined and the impact of prior or combined treatment with laser photocoagulation on the primary outcome is unclear. Results from ongoing studies should assess not only treatment efficacy but also, the number of injections needed for maintenance and long-term safety and the effect of any prior treatment.

Retinal vein occlusion (RVO) can have severe consequences for the people affected by the disease, including visual loss with costly social repercussions. Currently, there is no European consensus with regard to the management of RVO. Following a careful review of the medical literature as well as the data from several clinical trials, a collaborative group of retina specialists put forth practical recommendations based on the best available scientific evidence for the clinical approach to RVO. Taking into consideration the recent advances in diagnostic tools and management options, the present document aims to provide the European ophthalmologists with guidelines for clinical practice to the benefit of their patients.

We carried out a survey of important nonclinical issues including awareness and self-management of diabetes on a group of South Asian and Caucasian patients attending diabetic clinics within a set period.

A structured questionnaire examined various issues including demographics, perceived knowledge and awareness of diabetes, perceived self-help/support, and psycho-social factors. A total of 500 patients (268 South Asians and 232 Caucasian) took part.

Univariate analysis showed significant differences (P<0.05) with various issues including a lower perceived awareness of diabetes and its complications in South Asians, and of the nutritional content of their diet. Asians also appeared to be less worried in the event of missed clinical appointments and if treatment was not strictly adhered to.

The study provides evidence of the inability of health information systems to convey the importance of diabetic control to the Asian population. In order that this important information reaches the required recipients, more assertive and perhaps more culturally acceptable methods need to be explored.

To examine diabetic retinopathy in Asians and Caucasians attending a hospital diabetic clinic and to evaluate the impact of the significant risk factors on the probability of sight-threatening retinopathy.

A total of 500 diabetic patients (268 Asians, 232 Caucasians) who attended a diabetic clinic within a defined time period were examined for severity of diabetic retinopathy. The existence of sight-threatening retinopathy (STR) was compared in the two groups. Significant risk factors such as age, duration and hypertension were analysed against the probability of STR in each of the two races.

Asians demonstrated significantly higher rates of STR. Univariate analysis showed age, duration, race, gender, and insulin-requiring status to be significantly associated with STR. Multivariate logistic regression showed a significant association of STR with race, age and duration of diabetes, with no significant interaction effects between variables. The logistic regression model predicted STR in Asians to be matched to that in Caucasians by a 12.5-year difference factor; that is, Caucasians were older by 12.5 years or had a 12.5-year longer duration than Asians for the same level of STR.

After adjusting for age and duration of diabetes, the probability of STR in Asian diabetic patients attending the diabetic clinics in Bradford is significantly higher than that in Caucasians (odds ratio=3.184, P<0.05). The impact of age and duration was significantly higher in patients of South Asian origin compared to Caucasians.

Vitreous haemorrhage can be caused by a disruption of normal retinal vessels, bleeding from diseased retinal vessels, bleeding from abnormal new vessels or extension of haemorrhage through the retina from other sources. In the elderly, vitreous haemorrhage usually occurs spontaneously and only occurs occasionally as a result of trauma. Appropriate management of vitreous haemorrhage is dependent on the most likely cause in a particular patient. As always, an accurate medical history with a careful clinical examination, static and dynamic ultrasonography performed by an experienced examiner, results of other laboratory tests and an understanding of the common causes of vitreous haemorrhage in each age group is essential to come to a 'best guess' diagnosis as to the cause of the vitreous haemorrhage and thus guide the physician toward the appropriate management. Immediate surgical removal of blood if indicated, as well as improving the vision gives the added benefit of allowing a full examination of the underlying retina. For those in whom surgical removal of blood is not recommended, a careful and frequent follow-up with serial B-scan ultrasound allows the 'best guess' diagnosis to be confirmed at each visit, until such time as the vitreous haemorrhage resolves sufficiently to allow a full and proper examination of the retina. Where there is a confirmed retinal tear, retinal detachment or other fundal pathology these are treated appropriately with laser or surgery (vitrectomy). Preventative measures are dependent on the underlying cause of vitreous haemorrhage. Some of the underlying causes such as posterior vitreous detachment cannot be prevented. In others, such as retinal vein occlusion, measures may need to be taken so as to reduce the risk of a similar event in the same or fellow eye and to reduce the risk of potentially life-threatening associated systemic conditions such as a stroke or myocardial infarction.

Retinal vein occlusion (RVO) is associated with hyperhomocysteinaemia and the antiphospholipid syndrome-disorders known to contribute to both arterial and venous thrombosis. In both of these conditions and RVO, platelet activation occurs. Aspirin, not warfarin, is the most effective antithrombotic agent in RVO and, taken together, these observations suggest an important role for platelets in this common ocular thrombotic condition. Platelet glycoprotein Ia/IIa (GpIa/IIa) is an adhesion molecule mediating platelet-collagen interactions and is key to the initiation of thrombosis. Recently, the cellular density of this molecule was shown to be determined by two silent, linked polymorphisms (C807T/G873A) within the GpIa/IIa gene. There is evidence that some of the resulting genotypes are associated with thrombo-embolic disease. This study therefore aimed to establish the prevalence of the GpIa/IIa polymorphisms and the three commonest hereditary thrombophilic disorders (prothrombin gene G20210A (PT) mutation, Factor V Leiden (FVL), and the thermolabile methylene tetrahydrofolate reductase C677T (MTHFR) mutation) in patients with RVO and normal controls. The GpIa/IIa polymorphisms and thrombophilic abnormalities were all identified using the polymerase chain reaction.Our results show that the frequency of the GpIa/IIa polymorphisms was similar in our normal control population to previously published series. Patients with RVO, however, had only a 10% (4/40) frequency of the lowest risk subtype (CC/GG) compared to 37.5% (15/40) in the control group-P 0.0039. The incidence of the PT, FVL, and MTHFR thrombophilic mutations was not different between the two groups, but interestingly none of the 7/40 RVO cases with a PT, FVL, or MTHFR mutation had the low-risk GpIa/IIa genotype while all but one of the controls did-P<0.05. Thus, 17.5% of RVO patients harboured more than one prothrombotic abnormality. The principal difference between the RVO and control group was the very high incidence of the intermediate-risk GpIa/IIa subtype (CT/GA)-82.5 vs 50%, P&<0.05. These results suggest a major role for GpIa/IIa polymorphisms in the pathogenesis of RVO.

To identify risk factors for central retinal vein occlusion (CRVO).

This clinic-based case-control study included 408 patients with CRVO aged 21 years and older and 566 controls who were seen between January 1, 1990, and December 31, 2001. Multivariate logistic regression analysis was used to adjust for various factors and test potential interactions between the different variables.

An increased risk of CRVO was found in persons with systemic hypertension, but odds ratios were greater for older patients. Risk of CRVO increases with age and also in association with hypercoagulability. Diabetes mellitus, kidney disease, and glaucoma were associated with increased risk for CRVO. A significantly greater prevalence of higher erythrocyte sedimentation rate was present in young adults compared with older patients.

The results suggest a relationship between CRVO and certain risk factors (systemic hypertension, diabetes mellitus, kidney disease, glaucoma, older age) and support the possibility of an association between CRVO and urban location. The findings also support the potential value of medical treatment of underlying medical conditions in preventing occurrence of CRVO.

The aim of this study was to conduct a detailed retrospective follow-up of a large cohort of patients with retinal vein occlusion (RVO), examining morbidity and mortality, to investigate a possible relationship between RVO, large vessel disease and stroke, and to determine whether recurrence of RVO was influenced by treatment of associated medical conditions.

A follow-up study was undertaken in 1994 of all patients (n = 588) who presented to the medical ophthalmology clinics of the Birmingham and Midland Eye Hospital between 1982 and 1989 with a definitive diagnosis of RVO.

Follow-up data were obtained on 549 patients (93%). Results showed that recurrence of RVO in the same or fellow eye was decreased by more than half in the follow-up group (3.3%) when compared with the known recurrence rate at initial presentation (8.8%). Comparison of the deceased with the survivors showed that the deceased patients were significantly older (mean age 70.2 vs 63.4 years). The prevalence of rubeosis iridis and smoking were statistically significantly increased when comparing the deceased with the survivors (p < 0.016 and p < 0.008 respectively). The deceased had a higher prevalence of diabetes (15.8% vs 10.1%), and there was a trend towards increased clinically evident macrovascular disease in those patients who had died (23.2% vs 19.5%). Neither hypertension nor hyperlipidaemia predicted death, as the prevalence rates of the two conditions were similar in survivors and those who had died (60.0% vs 60.6% and 48.4% vs 53.3%). The percentage of patients taking antiplatelet drug therapy was not different in the two groups (36.8% vs 38.3%). Analysis of the causes of death of the RVO population (n = 95) compared with the causes of death in the West Midlands population as a whole, showed that the percentage of deaths from myocardial infarction in the RVO population was significantly higher (23.1% vs 14.4%, p < 0.05). There was no statistical difference between the populations for ischaemic heart disease and stroke, although there was a trend for increased mortality from stroke (19% vs 13.5%).

These data suggest a relationship between RVO, mortality and increased cardiovascular risk factors (smoking, diabetes and macrovascular disease), and support the possibility of an association between RVO and stroke. They also support the potential value of medical treatment of underlying medical conditions in preventing recurrence of RVO.

Hyperhomocysteinaemia has been linked to macrovascular disease. Our aim was to investigate whether there is a relationship between fasting plasma total homocysteine levels and retinal vascular disease.

We measured the homocysteine levels in 70 patients with arterial or venous retinal vessel occlusion and compared them with the levels in 85 controls without evidence of ischaemic heart disease. Homocysteine levels were determined by high-performance liquid chromatography with electrochemical detection and compared after logarithmic transformation.

Homocysteine levels were found by univariate analysis (unpaired two-tailed t-test) to be significantly higher in the group with retinal artery occlusion than the group with retinal vein occlusion (p = 0.045) and in both groups compared with controls (18.4 and 13.8 vs 9.5 mumol/l; p = 0.0002 and < 0.0001, respectively). The controls, however, were significantly younger than the subjects (51.5 +/- 15.4 vs 66.2 +/- 11.9 years; p < 0.0001), but analysis of the results by age revealed significant differences between the groups and controls for the seventh decade (vein occlusions, p = 0.05) and for the eighth decade (artery occlusions, p = 0.037). Subgroup analysis of the retinal vessel occlusion group revealed significant differences in mean blood pressure between those with branch retinal vein occlusions (175/100 mmHg) and both those with central retinal vein occlusions (155/88 mmHg) and those with retinal artery occlusions (157/86 mmHg). Both vein occlusion subgroups also differed significantly with regard to homocysteine levels, branch < central (12.2 +/- 1.3 vs 15.0 +/- 1.6 mumol/l, p = 0.03). Multiple linear regression analysis revealed significant relationships between homocysteine levels and the presence of retinal vessel occlusion (p = 0.0002), serum creatinine (p = 0.001) and age (p = 0.003), but not gender.

We conclude that homocysteine may be a risk factor for retinal vascular disease and could be simply and cheaply treated with folate and vitamins B6 and B12.

To determine the demographic characteristics, associated ophthalmic and systemic conditions of retinal vein occlusion (RVO) and associations of central retinal vein occlusion among Armenian patients.

A retrospective study of 460 patients aged 30 years and older with a clinical diagnosis of RVO who were seen in the five-year period between January 1, 1993, and December 31, 1997 at the Eye Hospital.

Signs of central RVO were found in 297 eyes (64.5%), branch RVO in 163 eyes (35.5%). Among the 460 patients occlusion was hemispheric in 4 eyes (2.4%), hemicentral in 5 eyes (3%). CRVO was more common among the younger patients (odds ratio [OR] = 2.42, 95% confidence interval [CI]: 1.06-5.65). Hypercoagulability was noted in the majority of RVO cases. Glaucoma was an associated condition (12.6%). Systemic hypertension was the most frequent association. In CRVO a significant association was found with hypertension (OR = 1.89, 95% CI: 1.23-2.70).

Our results suggest RVO is associated with glaucoma and hypertension. RVO was more closely associated with hypertension than BRVO. There were no differences in the distribution for the site of occlusion with regard to sex in patients with CRVO and BRVO. No seasonal pattern was found in the onset of any type of RVO. Hypercoagulability may be a contributing factor in the pathogenesis. The findings reinforce recommendations to carefully evaluate patients with RVO for open-angle glaucoma, and to diagnose and treat systemic hypertension.