Prevalence of lens opacities in Asian Malays.

PURPOSE: To describe the prevalence of lens opacities and cataract surgery in an older Malay population in Singapore. METHODS: The Singapore Malay Eye Study is a population-based cross-sectional study of 3280 (78.7% response rate) Malay adults aged 40-80 years. Participants underwent a standardized clinical eye examination. Digital slit-lamp and retroillumination photographs were taken of both eyes of each participant and graded for age-related nuclear, cortical and posterior subcapsular (PSC) cataract, following the Wisconsin Cataract Grading System. Other lens opacities, including retrodots and vacuoles, were also graded. Information on medical and lifestyle factors was collected using questionnaires. The study sample was directly age-standardized to the Malay population in Singapore using the 2000 Singapore population census. RESULTS: A total of 3054 (97.7%) and 3113 (99.6%) participants had gradable Topcon slit lamp and Neitz photographs, respectively. The overall age-adjusted prevalence of any cataract was 29.1%, and that of nuclear, cortical and PSC cataract were 12.9% (95% confidence interval, CI, 11.2-13.1%), 21.2% (95% CI 19.8-22.7%) and 9.7% (95% CI 8.8-10.8%), respectively. Age-adjusted prevalence of cataract surgery was 4.7% (95% CI 4.2-5.4%). Prevalence of all three cataract types and cataract surgery increased with age. Age-adjusted prevalence for retrodots and vacuoles were 19.7% (95% CI 18.3-21.1%) and 64.3% (95% CI 61.1-67.6%), respectively. Retrodots were found to be associated with prevalence of all three cataract types, while vacuoles were associated with cortical and PSC cataract prevalence. CONCLUSION: Lens opacities were common in this urban Malay population. Retrodots and vacuoles were found to be associated with age-related cataract.

Effect of blood pressure on the retinal vasculature in a multi-ethnic Asian population.

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.

Lack of awareness amongst community patients with diabetes and diabetic retinopathy: the Singapore Malay eye study.

INTRODUCTION: We assessed awareness of diabetes and diabetic retinopathy in a Singaporean Malay population. We hypothesised that poor awareness is associated with poorer control of diabetic retinopathy risk factors (glycaemic and blood pressure levels) and suboptimal treatment with laser therapy. MATERIALS AND METHODS: A population-based survey of 3280 (78.7% response rate) persons among Singaporean Malays aged between 40 and 80 years old. Diabetes was defined in persons with random glucose >or=11.1mmoL/L, use of diabetic medication, or a previous physician diagnosis. Diabetic retinopathy was graded from retinal photographs following the modified Airlie House classification. Patient awareness was assessed via structured interviews. Glycosylated haemoglobin was measured from venous blood. RESULTS: Of the 3280 study participants, 768 had diabetes, of whom 13.2% (n = 101) were unaware of their diabetes status. Participants unaware of their diabetes status had significantly higher mean glycosylated haemoglobin (9.7% vs 8.2%, P <0.001), systolic blood pressure (160.0 mmHg vs 153.7 mmHg, P = 0.01) and diastolic blood pressure (83.5 mmHg vs 78.5 mmHg, P <0.001), compared to participants who were aware. Of the 272 (35.4%) participants detected to have diabetic retinopathy, 83.4% (n = 227) were unaware of having retinopathy. Of the 77 with vision-threatening retinopathy, laser treatment had been performed in only 55.6% of those unaware of having retinopathy. CONCLUSION: In a sample of Malays with diabetes, high proportions were unaware of their disease. Unawareness was associated with poorer control of diabetic retinopathy risk factors. Only half of persons who were unaware that they had vision-threatening diabetic retinopathy had received laser treatment. These data highlight room for improvement in diabetic retinopathy prevention through better patient education and screening.

Prevalence and risk factors for refractive errors in the Singapore Malay Eye Survey.

PURPOSE: To describe the prevalence and risk factors for myopia and other refractive errors in an urban Malay population in Singapore. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: Persons of Malay ethnicity, between 40 and 80 years of age, living in Singapore. METHODS: Refractive error was determined by subjective refraction and if unavailable by autorefraction. Data were analyzed for 2974 adults without previous cataract surgery and who had right eye refraction data. Risk factor data, such as education levels and near work activity, were obtained from a face-to-face interview. MAIN OUTCOME MEASURES: Myopia, defined as spherical equivalent (SE) refraction less than -0.5 diopters (D), astigmatism as cylinder less than -0.5 D, hyperopia as SE greater than 0.5 D, and anisometropia as the difference in SE greater than 1.0 D. RESULTS: The prevalence of myopia in the right eye was 30.7% (9.4% unilateral myopia and 21.3% bilateral myopia), the prevalence of astigmatism in the right eye was 33.3% (95% confidence interval [CI, 33.0-33.5), the prevalence of hyperopia in the right eye was 27.4% (95% CI, 24.7-27.6), and the prevalence of anisometropia was 9.9% (95% CI, 9.7-10.0). There was a U-shaped relationship between increasing age and the prevalence of myopia, which was partially explained by the age-related increase in the prevalence of cataract. In a multiple logistic regression model, female sex, age, higher educational level, and cataract were associated with myopia. Adults with myopia were more likely to have astigmatism (P<0.001) in multivariate analyses. CONCLUSIONS: A quarter of older adult Malay people in Singapore had myopia. Compared with previous reports of similarly aged Singapore Chinese adults, the prevalence of myopia, astigmatism, and anisometropia was lower, whereas the prevalence of hyperopia was similar.

Prevalence of age-related macular degeneration in a Malay population: the Singapore Malay Eye Study.

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.

Fatal dengue hemorrhagic fever in adults during a dengue epidemic in Singapore.

BACKGROUND: Dengue fever has seen a significant re-emergence in Southeast Asia. Associated with the rise of dengue has been the increase in dengue-associated mortality. To better understand the predictors of mortality, we conducted a review of hospitalized adult dengue infections within our institution. METHODS: This was a retrospective case-control study of dengue-associated deaths at a large tertiary care hospital. RESULTS: In 2004, of 3186 cases of dengue fever (DF)/hemorrhagic dengue fever (DHF) admitted to our institution, there were 130 cases of DHF and seven dengue-associated deaths (case-fatality rate 5.4%). At least three of the seven fatal cases had serological evidence of primary dengue infection. All dengue-mortality cases had rapidly progressive clinical deterioration at an average of day 4 of fever with intensive care admission occurring on a mean of 5.6 days of fever. Adult respiratory distress syndrome, disseminated intravascular coagulopathy, and multi-organ failure were the most common causes of death despite early hospitalization, intravenous fluid, and blood-product support. CONCLUSION: Dengue is associated with severe disease, and deaths do occur despite current supportive management. Fatal DHF/dengue shock syndrome (DSS) does occur in adults and in primary dengue infection. Better early predictors of disease severity and clinical interventions are needed.