Prevalence and risk factors of diabetic retinopathy in migrant Indians in an urbanized society in Asia: the Singapore Indian eye study.
OBJECTIVE
To describe the prevalence of and risk factors for diabetic retinopathy (DR) in Indian persons living in a newly urbanized society in Asia.


METHODS
Population-based study.


METHODS
Ethnic Indians aged ≥40 years living in Singapore.


METHODS
The Singapore Indian Eye Study was conducted between 2007 and 2009. All participants underwent an extensive ophthalmic examination, including retinal photographs obtained after pupil dilation. These images were graded for the presence and severity of DR using the modified Airlie House classification system. Diabetes was defined as hemoglobin A1c level of ≥6.5%, use of diabetic medication, or a physician diagnosis of diabetes. Risk factors were measured using questionnaires, clinical assessments, or laboratory tests.


METHODS
Any DR, diabetic macular edema (DME), or vision-threatening DR (VTDR).


RESULTS
Among the 3400 participants, the age-standardized prevalence was 33.6% (95% confidence interval [CI], 31.4-35.8) for diabetes and 10.5% (95% CI, 9.3-11.8) for DR. Among those with diabetes only, the age-standardized prevalence was 30.4% (95% CI, 26.5-34.8) for any DR, 7.2% (95% CI, 5.3-9.7) for DME, and 7.1% (95% CI, 5.4-9.5) for VTDR. In multivariate analysis, independent risk factors for any DR were younger age (odds ratio [OR], 0.98; 95% CI, 0.96-1.00, per year increase), longer diabetes duration (OR, 1.09; 95% CI, 1.07-1.11 per year increase), higher hemoglobin A1c (OR, 1.23; 95% CI, 1.13-1.34 per percent increase), higher systolic blood pressure (OR, 1.01; 95% CI, 1.00-1.02 per 1-mmHg increase), lower diastolic blood pressure (OR, 0.97; 95% CI, 0.96-0.99 per 1-mmHg increase), history of previous stroke (OR, 2.16; 95% CI, 1.12-4.16), and insulin treatment (OR, 2.99; 95% CI, 1.84-4.87). Similar independent risk factors, except for blood pressure, were found for VTDR. Additionally, persons with lower income and living in smaller houses were associated with VTDR.


CONCLUSIONS
One in 3 migrant Indians living in newly urbanized Asian societies have diabetes and 1 in 10 has DR. This is similar to rates reported in Western populations and significantly higher than those reported in India.
Singapore Eye Research Institute, Singapore National Eye Centre, Singapore.
Yingfeng
Y
Zheng
Ecosse L
EL
Lamoureux
Raghavan
R
Lavanya
Renyi
R
Wu
M Kamran
MK
Ikram
Jie Jin
JJ
Wang
Paul
P
Mitchell
Ning
N
Cheung
Tin
T
Aung
Seang-Mei
SM
Saw
Tien Y
TY
Wong
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure; D003922:Diabetes Mellitus, Type 1 / Q000208:ethnology; D003924:Diabetes Mellitus, Type 2 / Q000208:ethnology; D003930:Diabetic Retinopathy / Q000175:diagnosis / Q000208:ethnology*; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007194:India / Q000208:ethnology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D012846:Singapore / Q000453:epidemiology; D011795:Surveys and Questionnaires; D013997:Time Factors; D014171:Transients and Migrants / Q000706:statistics & numerical data*; D014505:Urban Population / Q000706:statistics & numerical data*
D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human