Prevalence and risk factors for retinopathy in persons without diabetes: the Singapore Indian Eye Study

Optical coherence tomography angiography of the retina and choroid in systemic diseases

Optical coherence tomography angiography (OCTA) has transformed ocular vascular imaging, revealing microvascular changes linked to various systemic diseases. This review explores its applications in diabetes, hypertension, cardiovascular diseases, and neurodegenerative diseases. While OCTA provides a valuable window into the body's microvasculature, interpreting the findings can be complex. Additionally, challenges exist due to the relative non-specificity of its findings where changes observed in OCTA might not be unique to a specific disease, variations between OCTA machines, the lack of a standardized normative database for comparison, and potential image artifacts. Despite these limitations, OCTA holds immense potential for the future. The review highlights promising advancements like quantitative analysis of OCTA images, integration of artificial intelligence for faster and more accurate interpretation, and multi-modal imaging combining OCTA with other techniques for a more comprehensive characterization of the ocular vasculature. Furthermore, OCTA's potential future role in personalized medicine, enabling tailored treatment plans based on individual OCTA findings, community screening programs for early disease detection, and longitudinal studies tracking disease progression over time is also discussed. In conclusion, OCTA presents a significant opportunity to improve our understanding and management of systemic diseases. Addressing current limitations and pursuing these exciting future directions can solidify OCTA as an indispensable tool for diagnosis, monitoring disease progression, and potentially guiding treatment decisions across various systemic health conditions.

Prevalence of Retinopathy in Prediabetic Populations: A Systematic Review and Meta-Analysis

Among the leading causes of vision impairment and blindness globally, diabetic retinopathy (DR) is one of the most important causes. There is increasing evidence of DR prevalence in the prediabetic population. This systematic review presents collective data on retinopathy in the prediabetic population. This review article aimed to estimate the reported prevalence of retinopathy in prediabetes, impaired glucose tolerance test (GTT) without diabetes mellitus, and the risk factors involved and to summarize it. Literature searches were done using the Web of Science, CINAHL, Google Scholar, Cochrane, EMBASE, and PubMed databases from inception to April 2023. Our search included the words prediabetes, DR, and risk factors. All searches were looked at for methodological quality and evidence. Thirty-one studies were included after the screening. Population-based data were used in 23 studies (82.1%). The prediabetic population screened was 10,539. The prevalence of retinopathy ranged between 0.3% and 20.9%, showing a median of 8.1% with an interquartile range (IQR) of 4.2-11%, showing great variance in estimates due to the use of different screening methods, methods used for retinopathy grading, and study populations. Several studies compared the population with normal GTT with impaired glucose tolerance (IGT) and inferred that there was a lower prevalence of retinopathy in the normal GTT population (3.0%, IQR 0.3-7.4%) than prediabetes (6.7%, IQR 1.9-10.1%). According to this data, a greater retinopathy prevalence was found in prediabetic populations.

Retinal microvascular signs in COVID-19

BACKGROUND/AIMS

To explore if retinal findings are associated with COVID-19 infection.

METHODS

In this prospective cross-sectional study, we recruited participants positive for COVID-19 by nasopharyngeal swab, with no medical history. Subjects underwent retinal imaging with an automated imaging device (3D OCT-1 Maestro, Topcon, Tokyo, Japan) to obtain colour fundus photographs (CFP) and optical coherence tomographic (OCT) scans of the macula. Data on personal biodata, medical history and vital signs were collected from electronic medical records.

RESULTS

108 patients were recruited. Mean age was 36.0±5.4 years. 41 (38.0%) had symptoms of acute respiratory infection (ARI) at presentation. Of 216 eyes, 25 (11.6%) had retinal signs-eight (3.7%) with microhaemorrhages, six (2.8%) with retinal vascular tortuosity and two (0.93%) with cotton wool spots (CWS). 11 eyes (5.1%) had hyper-reflective plaques in the ganglion cell-inner plexiform layer layer on OCT, of which two also had retinal signs visible on CFP (CWS and microhaemorrhage, respectively). There was no significant difference in the prevalence of retinal signs in symptomatic versus asymptomatic patients (12 (15.0%) vs 13 (9.6%), p=0.227). Patients with retinal signs were significantly more likely to have transiently elevated blood pressure than those without (p=0.03).

CONCLUSION

One in nine had retinal microvascular signs on ocular imaging. These signs were observed even in asymptomatic patients with normal vital signs. These retinal microvascular signs may be related to underlying cardiovascular and thrombotic alternations associated with COVID-19 infection.

The New Era of Retinal Imaging in Hypertensive Patients

ABSTRACT

Structural and functional alterations in the microcirculation by systemic hypertension can cause significant organ damage at the eye, heart, brain, and kidneys. As the retina is the only tissue in the body that allows direct imaging of small vessels, the relationship of hypertensive retinopathy signs with development of disease states in other organs have been extensively studied; large-scale epidemiological studies using fundus photography and advanced semi-automated analysis software have reported the association of retinopathy signs with hypertensive end-organ damage includes the following: stroke, dementia, and coronary heart disease. Although yielding much useful information, the vessels assessed from fundus photographs remain limited to the larger retinal arterioles and venules, and abnormalities observed may not be that of the earliest changes. Newer imaging modalities such as optical coherence tomography angiography and adaptive optics technology, which allow a greater precision in the structural quantification of retinal vessels, including capillaries, may facilitate the assessment and management of these patients. The advent of deep learning technology has also augmented the utility of fundus photographs to help create diagnostic and risk stratification systems. Particularly, deep learning systems have been shown in several large studies to be able to predict multiple cardiovascular risk factors, major adverse cardiovascular events within 5 years, and presence of coronary artery calcium, from fundus photographs alone. In the future, combining deep learning systems with the imaging precision offered by optical coherence tomography angiography and adaptive optics could pave way for systems that are able to predict adverse clinical outcomes even more accurately.

The Application of Optical Coherence Tomography Angiography in Systemic Hypertension: A Meta-Analysis

Objective: Multiple studies have compared various optical coherence tomography angiography (OCTA) parameters in participants with systemic hypertension vs. controls and have presented discordant findings. We conducted a meta-analysis to pool together data from different studies to generate an overall effect size and find out whether OCTA parameter(s) significantly differed in participants with systemic hypertension as compared to controls. Methods: We conducted a literature search through a search of electronic databases to identify studies before 19 June 2021, which compared OCTA parameters in non-diabetic participants with systemic hypertension vs. controls. If the OCTA parameter had a minimum number of 3 studies that analyzed it, the mean difference between participants with systemic hypertension and controls were analyzed using a random-effects model. Results: We identified 11 eligible studies. At the macula, 9 studies analyzed vessel density at the superficial capillary plexus (SVD), 7 analyzed vessel density at the deep capillary plexus (DVD), and 6 analyzed the area of the superficial foveal avascular zone (FAZ). Participants with systemic hypertension had significantly lower SVD (standardized mean difference [SMD], -0.50 [-0.70, -0.30], P < 0.00001, I ² = 63%), lower DVD (SMD, -0.38 [-0.64, -0.13], P = 0.004, I ² = 67%) and larger superficial FAZ (SMD, 0.32 [0.04, 0.61], P = 0.020, I ² = 77%). Conclusion: The eyes of people with systemic hypertension have robustly lower superficial and deep vascular densities at the macula when compared to control eyes. Our results suggest that OCTA can provide information about pre-clinical microvascular changes from systemic hypertension.

Six-year incidence and systemic associations of retinopathy in a multi-ethnic Asian population without diabetes

PURPOSE

We described the 6-year incidence and changes of retinopathy, and their associated risk factors in a multi-ethnic Asian population without diabetes.

METHODS

We included 4374 participants with non-diabetes from a population-based cohort, the Singapore Epidemiology of Eye Disease Study, with gradable retinal photographs at baseline and 6-year follow-up visit. Retinopathy was assessed according to the modified Airlie House classification system.

RESULTS

Over the 6-year period, the cumulative rates were 2.5% (106/4279) for retinopathy incidence, 1.0% (1/95) for retinopathy progression and 68.4% (65/95) for retinopathy regression. In multivariable analysis, higher diastolic blood pressure (DBP) (risk ratio (RR)=1.02; 95% CI: 1.00 to 1.04; per 10 mm Hg increase in DBP) and wider retinal arteriolar calibre (RR=1.36; 95% CI: 1.13 to 1.63; per SD increase in central retinal artery equivalent) were associated with higher risk of incident retinopathy, while higher level of high-density lipoprotein (HDL) was associated with lower risk of incident retinopathy (RR=0.56; 95% CI: 0.32 to 0.99; per mmol/L increase in HDL). Compared with Chinese, Malays were more likely to have retinopathy regression (RR=1.63; 95% CI: 1.20 to 2.22), while overweight (RR=0.47; 95% CI: 0.26 to 0.84) and higher glycosylated haemoglobin (HbA1c) level (RR=0.58; 95% CI: 0.37 to 0.93; per per cent increase in HbA1c) were associated with lower likelihood of retinopathy regression.

CONCLUSION

Risk of developing retinopathy in Asians without diabetes is generally low. However, regression of retinopathy over time is common, suggesting that these retinopathy signs may reflect subclinical reversible microvascular dysfunction. Several metabolic risk factors are associated with incidence or regression of retinopathy, suggesting that good metabolic control may still be important in the management of non-diabetic retinopathy.

Association of glucose metabolism and retinopathy signs in non-diabetic individuals in midlife-The Northern Finland Birth Cohort 1966 study

Diabetic retinopathy is a microvascular complication of hyperglycaemia. Little is known about the association of glucose metabolism and retinopathy signs in the non-diabetic middle-aged population. We studied prevalence of retinopathy in a subsample of Northern Finland Birth Cohort study (NFBC1966) of 1809 subjects, at 47 years of age, without previously diagnosed type 2 diabetes and/or blood pressure-lowering medication. All participants underwent clinical evaluations including an oral glucose tolerance test (glucose and insulin values measured at 0, 30, 60 and 120 min) and HbA1c. The retinopathy signs were diagnosed by fundus photographs and classified according to the Eurodiab classification scheme. The overall prevalence of newly diagnosed retinopathy was 1.4%. The retinopathy signs were significantly associated with increased 30 min, 1-h and 2-h glucose levels and 2-h insulin level in an OGTT. After adjustment with systolic blood pressure, only 30 min glucose, 1-h glucose and 2-h insulin levels were associated with retinopathy signs. Our findings show the potential role of 30 min and 1-h post-load glucose and 2-h insulin levels as risk factors for retinopathy lesions among the participants without previously diagnosed diabetes or hypertensive medication.

POSTERIOR FUNDUS HEMORRHAGES: Frequency and Associated Factors: The Beijing Eye Study

PURPOSE

To examine frequency and associations of retinal hemorrhages.

METHODS

The population-based Beijing Eye Study included 3,468 individuals. Monoscopic fundus photographs were examined for hemorrhages.

RESULTS

Retinal hemorrhages were detected in 515 eyes (429 individuals) (prevalence: 7.6%; 95% confidence interval [CI]: 7.0-8.0 per eye; 12.7%; 95% CI: 11.7-13.7 per person). Higher prevalence of retinal hemorrhages was correlated (multivariate analysis) with higher systolic blood pressure (P < 0.001; odds ratio: 1.02; 95% CI: 1.01-1.03), higher prevalence of diabetic retinopathy (P < 0.001; odds ratio: 121; 95% CI: 61-240), and higher prevalence of retinal vein occlusions (P < 0.001; odds ratio: 27; 95% CI: 17-42). Retinal hemorrhages were due to diabetic retinopathy (189 [36.7%] eyes), retinal vein occlusions (n = 65 [12.6%]), posterior vitreous detachment (n = 23 [4.5%]), glaucoma (n = 14 [2.7%]), exudative age-related macular degeneration (n = 8 [1.6%]), hypertensive retinopathy (n = 10 [1.9%]), and exudative myopic maculopathy (n = 1 [0.2%]). Retinal hemorrhages without evident ocular cause ("NOH") were detected in 204 (3.0%) eyes (or 39.6% of all retinal hemorrhages). Higher prevalence of NOHs was correlated with higher systolic blood pressure (P < 0.001; odds ratio: 1.02; 95% CI: 1.01-1.03) after adjusting for blood glucose concentration and prevalence of cortical cataract.

CONCLUSION

In a population-based recruited cohort of individuals aged 50+ years, prevalence of any fundus hemorrhage was about 8% per eye and 13% per individual. Approximately 60% of the hemorrhages were due to ocular reasons, mainly diabetic retinopathy, retinal vein occlusions, and posterior vitreous detachment, whereas 40% of the bleedings were not evidently associated with ophthalmologic causes but strongly with elevated systolic blood pressure.

Gender-Specific Association between Serum Uric Acid and Incident Fundus Arteriosclerosis in Chinese Population: A Retrospective Cross-Sectional Study

Elevated levels of serum uric acid (SUA) were considered to be risk factors for cardiovascular disease, it has been found to be associated with increased arteriosclerosis. The aim of this study was to explore the gender specific relationship between SUA and fundus arteriosclerosis in a healthy population. In a retrospective cross-sectional study, 23474 individuals without diabetes and hypertension were included in the present study. SUA levels were cut to four groups as Q1 to Q4, according to the quartiles. The odds ratio and 95% confidence interval of different SUA levels were estimated by a binomial logistic regression model. A restrictive cubic spline method was used to estimate the dose-response relationship between SUA and fundus arteriosclerosis. Subgroup analysis was performed to find the gender-specific association between SUA and incident fundus arteriosclerosis. In males, after adjusting for confounding factors, the highest SUA level was significantly associated with the risk of incident fundus arteriosclerosis. The OR with 95%CI for Q4 was 1.44(1.18, 1.76), Q1 as a reference. Specially, for females, SUA level was not associated with the incidence of fundus arteriosclerosis. In conclusion, elevated levels of SUA were associated with the incidence of fundus arteriosclerosis in males, but not in females.

Impact of hypertension on retinal capillary microvasculature using optical coherence tomographic angiography

Objective:

Reduction in capillary density or rarefaction is a hallmark of essential hypertension. We measured the retinal capillary density using noninvasive optical coherence tomographic angiography (OCT-A) in adults with treated systemic hypertension and determined possible correlations with ambulatory blood pressure (BP) and renal parameters.

Methods:

This observational cross-sectional study consisted of 153 normal eyes from 77 nondiabetic hypertensive adults [mean (SD) age, 58 (9) years; 49% women; 23% poorly controlled BP]. Data on 24-h ambulatory BP monitoring, serum creatinine, and urine microalbumin/creatinine ratio (MCR) were collected. Estimated glomerular filtration rate (eGFR) was calculated based on CKD-EPI Creatinine Equation. Retinal capillary density measured with the OCT-A (AngioVue) at superficial (SVP) and deep vascular plexuses (DVP). Linear regression was used to investigate the association of risk factors with capillary density.

Results:

Retinal capillary density (percentage) at DVP was reduced in patients with poorly controlled BP (SBP = 148 ± 8 mmHg; 27.2 ± 13.0) compared with those with well controlled BP (SBP = 125 ± 9 mmHg; 34.7 ± 11.3). In the multivariable analysis, poorly controlled BP [β = −6.49, 95% confidence interval (CI), −12.39 to −0.59], higher SBP (β = −0.23, 95% CI −0.44 to −0.02) and lower eGFR (β = 6.42, 95% CI 1.25–11.60) were associated with sparser retinal capillary density. Systemic factors were not associated with capillary density at SVP (all P > 0.05).

Conclusion:

In adults with treated systemic hypertension, retinal capillary density reduced with higher BP and poorer eGFR. These findings highlight the potential role of OCT-A to study early microvascular changes because of systemic hypertension.

Retinal Microvascular Abnormalities in Children with Type 1 Diabetes Mellitus Without Visual Impairment or Diabetic Retinopathy

Purpose

To study the characteristics and associated factors of retinal microvascular abnormalities in children with type 1 diabetes mellitus (T1DM) without visual impairment and diabetic retinopathy (DR).

Methods

Case-control hospital-based study including children with or without DM. Optical coherence tomography angiography (OCTA; CIRRUS HD-OCT model 5000) was used to scan 6 × 6 mm square area of posterior retina and optic disc. The indexes analyzed mainly included vascular length density (VD), perfusion density (PD), and foveal avascular zone area, perimeter, and morphology. Independent risk factors were analyzed by multifactor linear regression.

Results

A total of 47 children with T1DM and 44 healthy subjects were enrolled. Statistical analysis showed that VD within 1 to 3 mm (inner ring) of the macula in the case group was smaller than that in the control group (18.561 ± 1.151/mm: 19.161 ± 0.464/mm; P< 0.001), and mother's excessive weight gain during pregnancy was an independent factor (P = 0.004); VD within 3 to 6 mm (outer ring) of the macula in the case group was smaller than that in the control group (19.044 ± 0.847/mm; 19.404 ± 0.496/mm, P = 0.029), while serum creatinine level was revealed to be an independent factor (P = 0.009); PD within 3 to 6 mm of the macula in the case group was higher than that in the control group (0.456 ± 0.015: 0.442 ± 0.030) (P = 0.003), with no independent factor observed in regression analysis.

Conclusion

Retinal microvasculopathy had already occurred in the parafoveal area of diabetic children without visual impairment and DR; early screening and close follow-up were recommended for children with high-risk factors.

Prevalence and risk profile of retinopathy in non-diabetic subjects: National Health and Nutrition Examination Survey 2005 to 2008

IMPORTANCE

Recent US national population-based data on the prevalence of retinopathy in non-diabetic participants is limited.

BACKGROUND

To assess the prevalence and risk factors of retinopathy in a representative US population without diabetes.

DESIGN

Population-based, cross-sectional study.

PARTICIPANTS

A total of 4354 non-diabetic participants 40 years and older with valid fundus photographs in the 2005 to 2008 National Health and Nutrition Examination Survey.

METHODS

Diabetes mellitus was defined as glycosylated haemoglobin (HbA1c) ≥6.5%, physician diagnosis of diabetes mellitus or use of diabetic medication. Retinopathy level was based on the Modified Airlie House adaptation from the Early Treatment Diabetic Retinopathy Study (ETDRS) protocol. Risk profile was assessed from standardized interviews, clinical examinations and laboratory measurements.

MAIN OUTCOME MEASURES

Prevalence and risk profile of retinopathy in non-diabetic participants.

RESULTS

The overall weighted prevalence of retinopathy was 6.7% (n = 341). Among them, 98.2% (n = 331) had signs of minimal-to-mild non-proliferative retinopathy (ETDRS level 14-31) while only 1.8% (n = 10) had moderate-to-severe non-proliferative retinopathy (ETDRS level 41-51). After adjusting for multiple covariates, retinopathy signs in non-diabetic participants were associated with male gender (odds ratio [OR] 1.54; 95% confidence interval [CI] 1.22-1.93), systolic blood pressure (OR per 10 mmHg increase 1.11; 95% CI 1.03-1.19), HbA1c (OR per % increase 1.43; 95% CI 1.01-2.05) and history of stroke (OR 2.39; 95% CI 1.14-5.04).

CONCLUSIONS AND RELEVANCE

Consistent with previous studies, signs of retinopathy are common in US persons without diabetes. Risk factors for retinopathy signs include gender, blood pressure, HbA1c and history of stroke.

Impact of systemic vascular risk factors on the choriocapillaris using optical coherence tomography angiography in patients with systemic hypertension

We investigated the characteristics of the choriocapillaris flow voids using optical coherence tomography angiography (OCTA) in 85 patients (164 eyes) with hypertension (mean ± SD age, 56 ± 11 years; 45% women; 20% poorly controlled BP; 16% diabetes) who are without ocular diseases and determined possible correlations with systemic vascular risk factors. Data on 24-hour ambulatory blood pressure (BP), serum creatinine, and urine microalbumin/creatinine ratio (MCR) were collected. Estimated glomerular filtration rate (eGFR) was calculated based on CKD-EPI Creatinine Equation. OCTA imaging (6 × 6 mm scans; AngioVue) with quantitative microvascular analysis of the choriocapillaris was performed. Linear regression was used to investigate the association of systemic risk factors with area (percentage), size (pixels) and number of choriocapillaris flow voids. Diabetes (β = 0.33; 95% CI, 0.02 to 0.63) and daytime systolic BP (β = -0.13; 95% CI, -0.24 to -0.02) were associated with areas of flow voids. Age (β = 0.21; 95% CI, 0.06 to 0.36) and daytime diastolic BP (β = -0.18; 95% CI, -0.34 to -0.02) were associated with size of flow voids. Age (β = -21.21; 95% CI, -31.79 to -10.63) and nighttime diastolic BP (β = 13.89; 95% CI, 0.61 to 27.17) were associated with number of flow voids. Kidney parameters were not associated with any features of flow voids. In patients with hypertension, a higher BP appeared to increase blood flow in the choriocapillaris which needs to be considered when using the OCTA to study eye diseases in hypertensives.

Obesity, metabolic syndrome and diabetic retinopathy: Beyond hyperglycemia

Diabetic retinopathy (DR) is the most feared ocular manifestation of diabetes. DR is characterized by progressive retinal damage that may eventually result in blindness. Clinically, this blindness is caused by progressive damage to the retinal microvasculature, which leads to ischemia, retinal swelling, and neovascularization. Retinopathy is associated with both type 1 and type 2 diabetes, with DR being the leading cause of new onset blindness in United States adults. Despite this strong association with diabetes, it must be noted that the development of retinopathy lesions is multifactorial and may occur in individuals without an established history of diabetes. Metabolic syndrome is a multifactorial condition of central obesity, hypertriglyceridemia, dyslipidemia, hypertension, fasting hyperglycemia, and insulin resistance. Although several studies examined the individual components observed in the metabolic syndrome in relation to the development of DR, there is conflicting data as to the association of the metabolic syndrome with the development of retinopathy lesions in non-diabetic subjects. This review will summarize the current literature on the evidence of the metabolic syndrome on retinopathy in subjects with and without an established history of diabetes. This review will also discuss some of the mechanisms through which metabolic syndrome can contribute to the development of retinopathy.

Diabetic polyneuropathy and the risk of developing diabetic retinopathy: a nationwide, population-based study

PURPOSE

To assess the relationship between diabetic polyneuropathy (DPN) and the risk of diabetic retinopathy (DR).

METHODS

From 1997 to 2010, we identified 5031 newly diagnosed DPN patients and 20 124 controls matched for sex, age, and index year. Cox proportional hazards regression analyses were used to estimate the adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of DR between the DPN patients and the non-DPN group. The adjusted hazard ratio was calculated and adjusted for age, sex, duration of diabetes and comorbidities of hypertension, cardiovascular disease and diabetic nephropathy.

RESULTS

The incidence rate of DR was 5.87-fold higher in the DPN patients than in the non-DPN group (44.0 vs. 7.22 per 1000 person-years), with an adjusted HR of 5.41(95% CI = 4.92-5.94). The DPN-to-non-DPN DR incidence rate ratio decreased with age (adjusted HR = 6.63 for subgroup younger than 65 years and adjusted HR = 3.91 for subgroup aged 65 years or older). Compared with the non-DPN group, the DPN patients had a 5.63-fold risk of non-proliferative DR (adjusted HR = 5.63, 95% CI = 5.11-6.21) and a 3.67-fold risk of proliferative DR (adjusted HR = 3.67, 95% CI = 2.57-5.23).

CONCLUSION

The patients with DPN had an increased risk of developing DR and advanced DR compared with the non-DPN group, particularly among the subgroup aged younger than 65 years.

The rs6060566 of the reactive oxygen species modulator 1 (Romo-1) gene affects Romo-1 expression and the development of diabetic retinopathy in Caucasians with type 2 diabetes

PURPOSE

The aim of this study was to examine the role of the rs6060566 polymorphism of the reactive oxygen species modulator 1 (Romo-1) gene in the development of diabetic retinopathy (DR) in Caucasians with type 2 diabetes (T2DM). Moreover, another aim was to investigate the effect of Romo-1 genotypes on Romo-1 expression in fibrovascular membranes from patients with proliferative DR.

METHODS

A total of 806 subjects with T2DM were enrolled in cross-sectional case-control study: 278 patients with DR and 528 subjects without clinical signs of DR. Genetical analysis was performed in 806 subjects with T2DM. Moreover, immunohistochemical analysis of 40 fibrovascular membranes of patients with proliferative DR was performed. The number of positive (labelled) cells per area - numerical areal density of the Romo-1-positive cells (the number of positive cells/mm(2) ) - was calculated.

RESULTS

A significantly higher frequency of the CC genotype of the rs6060566 polymorphism of the Romo-1 gene was found in subjects with T2DM with DR compared to those without DR (odds ratio=3.3, 95% confidence interval=1.1-8.8; p = 0.024). Moreover, the Romo-1 C allele was found to effect Romo-1 expression in fibrovascular membranes of patients with proliferative DR.

CONCLUSIONS

The rs6060566 polymorphism of the Romo-1 gene was found to be an independent risk factor for DR in Caucasians with T2DM. Moreover, the rs6060566 is most probably functional and its effect might be mediated through the increased expression of Romo-1 in the retina.