Search

Purpose: To investigate the association between the characteristics of the retinal vascular network in the elderly and retinal nerve fiber layer (RNFL) thickness in a population-based study. Methods: We conducted a population-based study, the Montrachet study (Maculopathy Optic Nerve, nuTRition neurovAsCular, and HEarT disease), in participants aged ≥ 75 years. RNFL thickness was assessed with spectral-domain optical coherence tomography (SD-OCT). Analysis of the retinal vascular network was performed by means of the Singapore "I" Vessel Assessment (SIVA) software based on fundus photography. Results: Data from 970 participants were suitable for analysis. Patients with optic neuropathy were excluded. In multivariable analysis, each standard deviation (SD) decrease in the caliber of the six largest arterioles and veins in zone B and the six largest arterioles and veins in zone C was associated with a decrease in global RNFL thickness (β = −1.62 μm, P = 0.001; β = −2.39 μm, P < 0.001; β = −1.56 μm, P = 0.002; and β = −2.64 μm, P < 0.001, respectively). Conclusions: Our study found that decreased retinal vessels caliber were associated with a decreased RNFL thickness in the elderly without optic neuropathy. [ABSTRACT FROM AUTHOR]

Purpose: To compare the frequency and pattern of bilateral involvement of early and late age-related macular degeneration (AMD) between Asian Malays and Caucasians. Methods: We used cross-sectional data from the baseline examination for subjects aged 50-79 years in the Singapore Malay Eye Study (SiMES) ( N == 2,453) and the Blue Mountains Eye Study (BMES) ( N == 3,265). We assessed AMD signs using a common protocol modified from the Wisconsin Age-related Maculopathy Grading System at the University of Sydney. We compared frequencies or proportions of AMD cases with bilateral involvement between the two populations. Results: There were 173 cases and 169 cases with any AMD (either early or late AMD in at least one eye), and 78 cases (45.1%) and 52 cases (30.8%) with bilateral AMD in the BMES and the SiMES, respectively. Age-standardized frequency of bilateral involvement was comparable between the BMES (29.5%, 95% confidence interval(CI) 18.5-40.5%) and the SiMES (25.6%, 95%CI 17.0-34.0%). Older age was associated with higher risk of bilateral AMD (gender-adjusted odds ratio per 1 year for the BMES and the SiMES: 1.08 [95% CI 1.05-1.11] and 1.06 [95% CI 1.02-1.10], respectively). Conclusions: The frequency of bilateral AMD was comparable between Asian Malays in the SiMES and the Caucasian population of the BMES. Other than older age, we did not find any characteristics associated with the bilateral involvement of AMD. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the relationship between retinal vascular caliber and age-related macular degeneration (AMD). Design: Population-based cross-sectional study. Methods: Three thousand two hundred and eighty (78.7% response rate) Malay Singaporeans aged 40 to 80 years residing in 15 districts of Singapore underwent retinal photography. Retinal vessel caliber was measured from retinal photographs using a validated computer-based technique. AMD was assessed following a modified Wisconsin Age-Related Maculopathy Grading System. Results: Retinal data were available from 3,265 subjects (99.5% of 3,280) for this study. Early and late AMD prevalence were 4.9% (n = 160) and 0.7% (n = 23) of the population, respectively, or in 205 (3.1%) and 30 (0.5%) eyes examined, respectively. After controlling for age and arteriolar caliber, wider venular caliber was associated with higher prevalence of early AMD (odds ratio [OR] per one standard deviation [SD] increment in venular caliber, 1.53; 95% confidence interval [CI], 1.13 to 2.09). This association remained significant after further adjustment for gender, smoking, hypertension, diabetes, and body mass index (OR per one SD, 1.52; 95% CI, 1.11 to 2.09). There was no significant association between retinal arteriolar caliber and early AMD, or between arteriolar or venular caliber and late AMD. Conclusions: Wider venular caliber was associated independently with early AMD. This finding may suggest that pathogenic processes linking to wider venular caliber be shared by early AMD and common cardiovascular risk factors such as inflammation, dyslipidemia, and endothelial dysfunction. [Copyright &y& Elsevier]

Objective: To assess the influence of the spectrum of diabetic retinopathy (DR) on vision-specific function in an Asian population. Design: Population-based cross-sectional study. Participants: Persons aged 40 to 80 years of Malay ethnicity in Singapore. Methods: The Singapore Malay Eye Study was a population-based, cross-sectional study of 3280 Asian Malays (78.7% response rate). Five end points were considered: (1) any DR, (2) macular edema (ME), (3) clinically significant macular edema (CSME), (4) vision-threatening DR (VTDR), and (5) DR severity levels ranging from none to proliferative diabetic retinopathy (PDR). Vision function was assessed using the Vision-Specific Functioning Scale validated using Rasch analysis. Main Outcome Measures: Vision-specific functioning score. Results: Of 357 diabetic participants in the study, 23.2% had any DR, 5.6% had ME, 5.0% had CSME, 10.6% had VTDR, and 6.2% had PDR. In linear regression models adjusting for age, gender, stroke, diabetic risk factors, and socioeconomic factors, poorer vision-specific function was associated independently with any DR (β, –0.21; P<0.05), ME (β, –0.48; P<0.05), CSME (β, –0.42; P<0.05), VTDR (β, –0.64; P<0.05), and PDR (β, –0.92; P<0.001). When controlling further for presenting visual acuity, VTDR (β, –0.37; P = 0.01) and PDR (β, –0.61; P = 0.002) were the only 2 DR categories independently associated with poorer vision-specific function and PDR. Persons with VTDR and PDR were 6 to 12 times more likely to report lower participation in daily living activities than those without these DR levels. Conclusions: People with VTDR and PDR have substantial difficulty undertaking vision-specific daily activities. These findings reinforce the importance of preventative efforts targeted at the earliest DR stages to prevent progression to later stages of DR. Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references. [Copyright &y& Elsevier]

Purpose: Assessment of cardiovascular risk is the keystone of prevention in cardiovascular disease. The objective of this pilot study was to estimate the cardiovascular risk score (American Hospital Association [AHA] risk score, Syntax risk, and SCORE risk score) with machine learning (ML) model based on retinal vascular quantitative parameters., Methods: We proposed supervised ML algorithm to predict cardiovascular parameters in patients with cardiovascular diseases treated in Dijon University Hospital using quantitative retinal vascular characteristics measured with fundus photography and optical coherence tomography - angiography (OCT-A) scans (alone and combined). To describe retinal microvascular network, we used the Singapore "I" Vessel Assessment (SIVA), which extracts vessel parameters from fundus photography and quantitative OCT-A retinal metrics of superficial retinal capillary plexus., Results: The retinal and cardiovascular data of 144 patients were included. This paper presented a high prediction rate of the cardiovascular risk score. By means of the Naïve Bayes algorithm and SIVA + OCT-A data, the AHA risk score was predicted with 81.25% accuracy, the SCORE risk with 75.64% accuracy, and the Syntax score with 96.53% of accuracy., Conclusions: Performance of these algorithms demonstrated in this preliminary study that ML algorithms applied to quantitative retinal vascular parameters with SIVA software and OCT-A were able to predict cardiovascular scores with a robust rate. Quantitative retinal vascular biomarkers with the ML strategy might provide valuable data to implement predictive model for cardiovascular parameters., Translational Relevance: Small data set of quantitative retinal vascular parameters with fundus and with OCT-A can be used with ML learning to predict cardiovascular parameters.

Objective: To describe the prevalence of and risk factors for age-related macular degeneration (AMD) in a multiethnic Asian cohort of Chinese, Malay, and Indian persons., Methods: In this population-based study, 3172 persons of Chinese, Malay, and Indian ethnicities 40 years and older were included. Participants underwent comprehensive systemic and ocular examination, retinal photography, and laboratory investigations. Early and late AMD signs were graded from retinal photographs. Age-standardized prevalence estimates were calculated using the 2010 Singapore adult population as the standard population. Association with a range of systemic risk factors was analyzed., Results: Of 3172 participants, AMD was present in 211 subjects. Age-standardized prevalence of AMD was 7.0% in persons 40 years and older. The age-standardized prevalence was similar in all 3 Asian ethnic groups: Chinese, 7.3%; Malay, 7.7%; and Indian, 5.7% (P value = .44). The prevalence increased with age and was higher in men. Of the range of risk factors evaluated, only myopic refractive error (<-0.5 D) was significantly associated with a lower risk for AMD (odds ratio, 0.44; P < .001, compared with emmetropia) in Chinese men., Conclusions: The prevalence of AMD was similar in the 3 major ethnic groups in Asia and comparable with white populations. Myopic refractive error was associated with reduced risk of AMD in Chinese men.

Purpose: To describe the association between refractive errors, ocular biometry, and age-related macular degeneration (AMD) in an Asian Malay population in Singapore., Methods: A population-based study of 3280 Malay individuals aged 40 to 80 years was conducted in Singapore. Early- and late-AMD signs were graded from retinal photographs according to the Wisconsin grading system. Autorefraction, followed by subjective refraction, was performed to obtain spherical equivalent refraction (SER) in diopters, with emmetropia defined as SER -0.5 to +0.5 D, hyperopia as > +0.5 D, and myopia as < -0.5 D. Partial coherence laser interferometry was used to measure axial length, anterior chamber depth, and corneal curvature. The association between refractive status, ocular biometry and the prevalence of both early and late AMD were analyzed., Results: Hyperopic refractive error (odds ratio [OR] 1.54; 95% confidence interval [CI] 1.00-2.36; compared with myopia, P = 0.05), shorter axial length (OR, 1.91; CI, 1.05-3.46, comparing 1st vs. 4th quartiles; P = 0.03), and steeper corneal curvature (OR, 1.93; CI, 1.16-3.20, comparing 1st vs. 4th quartiles, P = 0.01) were significantly associated with early AMD, after adjustment for age, sex, smoking, education, height, and systolic blood pressure. Each diopter increase in hyperopic refraction and each millimeter decrease in axial length was associated with an 8% (OR, 1.08; CI, 1.01-1.16; P = 0.03) and 29% (OR, 1.29; CI, 1.06-1.57; P = 0.01) increased risk of early AMD, respectively. No significant association was noted of refractive error and ocular biometry with late AMD., Conclusions: Hyperopic refractive error and shorter axial length are associated with early AMD in Asian eyes.

Blood pressure has a significant effect on retinal arterioles. There are few data on whether this effect varies by race/ethnicity. We examined the relationship of blood pressure and retinal vascular caliber in a multi-ethnic Asian population. The study is population-based and cross sectional in design. A total of 3749 Chinese, Malay and Indian participants aged > or =24 years residing in Singapore were included in the study. Retinal vascular caliber was measured using a computer program from digital retinal photographs. The associations of retinal vascular caliber with blood pressure and hypertension in each racial/ethnic group were analyzed. The main outcome measures are retinal arteriolar caliber and venular caliber. The results show that retinal arterioles were narrower in persons with uncontrolled/untreated hypertension (140.0 microm) as compared with persons with controlled hypertension (142.1 microm, P=0.0001) and those with no hypertension (146.0 microm, P<0.0001). On controlling for age, gender, body mass index, lipids and smoking, each 10 mm Hg increase in mean arterial blood pressure was associated with a 3.1 microm decrease in arteriolar caliber (P<0.0001), with a similar magnitude seen in all three racial/ethnic groups: 3.1 microm in Chinese, 2.8 microm in Malays and 3.2 microm in Indians (P<0.0001 for all). Each 10 mm Hg increase in mean arterial blood pressure was associated with a 1.8 microm increase in venular caliber (P<0.0001); furthermore, the magnitude of this effect was similar across the three racial/ethnic groups. The effect of blood pressure on the retinal vasculature was similar across three major racial/ethnic groups in Asia.

Objective: The aim of this study was to examine the relationship of retinal vascular caliber with diabetes and impaired fasting glucose (IFG) in a multiethnic Asian population., Methods: This work was a population-based cross-sectional study comprising 3,404 Singaporean Chinese, Indian, and Malay participants. Retinal arteriolar and venular diameters, CRAE and CRVE, respectively were measured from digital retinal photographs. Diabetes was defined as physician-diagnosis of diabetes, self-reported use of diabetic medication, or fasting plasma glucose (FPG) > or = 7 mmol/L; IFG as FPG 6.1-6.9 mmol/L., Results: After adjusting for age, gender, ethnicity, systolic blood pressure, body mass index, total cholesterol, triglycerides, smoking, and vascular caliber (Model 3), participants with diabetes had both larger CRAE and CRVE, compared to those with normal fasting glucose (NFG) or IFG. In a multivariate analysis, including clinical risk factors and CRVE, mean CRAE increased from 143.6 microm in NFG to 145.3 microm with diabetes (P for trend = 0.01). On the other hand, each mmol/L increase in FPG was associated with a 0.51-microm increase in CRVE (P=0.006). In a subgroup analysis stratified by ethnicity, the association between FPG and larger CRVE was predominantly present among ethnic Indians (0.9-microm increase in CRVE per mmol/L increase in FPG)., Conclusion: Diabetes was associated with larger retinal arteriolar diameters and glucose level was associated with larger retinal venular diameters in this multiethnic Asian population. The magnitude of association between glucose level and venular widening was stronger among ethnic Indians.

Objective: To describe the prevalence of age-related macular degeneration (AMD) in an Asian Malay population., Design: Population-based cross-sectional study., Participants: An age-stratified random sample of Malay persons aged 40 to 80 years living in Singapore., Methods: Participants were invited to a central clinic for a comprehensive examination., Main Outcome Measures: Early and late AMD signs were graded from retinal photographs following the Wisconsin grading system., Results: Of 3280 participants who participated (78.7% response rate), 3265 had photographs of sufficient quality for grading of AMD signs. Early and late AMD were present in 160 (4.9%) and 23 (0.70%) participants, respectively. After age standardization, the prevalence of early AMD in Malay persons aged 40 to 80 years was estimated to be 3.5% (95% confidence interval [CI], 2.9%-4.1%) and that of late AMD was 0.34% (95% CI, 0.20%-0.49%). Early AMD was more prevalent in men than in women (6.1% vs. 3.8%); this was significant despite adjusting for age and smoking (odds ratio [OR], 1.56; 95% CI, 1.11-2.20). Late AMD also was more prevalent in men than in women (1.0% vs. 0.4%), although this was not statistically significant after adjusting for age and smoking (OR, 1.39; 95% CI, 0.52-3.68). The prevalence of early and late AMD was similar to that reported in the Blue Mountains Eye Study among white persons., Conclusions: The prevalence of AMD in Asian Malay people is similar to that in white persons from the Blue Mountains Eye Study. Early AMD signs were more frequent in men compared with women, an association that was not fully explained by the higher smoking rates in men.