Risk factors for microvascular complications of diabetes among South Indian subjects with type 2 diabetes--the Chennai Urban Rural Epidemiology Study (CURES) Eye Study-5.
BACKGROUND
This study assessed the relationship between and risk factors for microvascular complications of diabetes in an urban South Indian type 2 diabetes population.


METHODS
Subjects with diabetes (n = 1,736) were selected from the population-based Chennai Urban Rural Epidemiology Study (CURES) Eye Study conducted on a representative population of Chennai city in south India. Four-field stereo retinal color photography was done, and diabetic retinopathy (DR) was classified according to the Early Treatment DR Study grading system. Neuropathy was diagnosed if the vibratory perception threshold of the big toe using biothesiometry was ≥ 20V. Overt nephropathy was diagnosed if the subjects had persistent macroalbuminuria (urinary albumin excretion ≥ 300 μg/mg of creatinine) and microalbuminuria if it was between 30 and 299 μg/mg of creatinine. Among the 1,715 subjects with gradable fundus photographs, 1,608 individuals who had information on all test parameters were included.


RESULTS
Overall, DR was present in 282 (17.5%), neuropathy in 414 (25.7%), overt nephropathy in 82 (5.1%), and microalbuminuria in 426 (26.5%) subjects. Eighteen subjects had all three microvascular complications of diabetes. The risk of nephropathy (odds ratio [OR] = 5.3, P<0.0001) and neuropathy (OR = 2.9, P<0.0001) was significantly higher among the subjects with sight-threatening DR compared to those without DR. Common risk factors identified for all the three microvascular complications of diabetes were age, glycated hemoglobin, duration of diabetes, and serum triglycerides. DR was associated with nephropathy after adjusting for age, gender, hemoglobin A1c, systolic blood pressure, serum triglycerides, and duration of diabetes (OR = 2.140, 95% confidence interval = 1.261-3.632, P = 0.005).


CONCLUSIONS
This is the first population-based study from India to report on all microvascular complications of diabetes and reveals that the association between DR and nephropathy is stronger than that with neuropathy.
Pradeepa
Rajendra
R
Madras Diabetes Research Foundation and Dr Mohan's Diabetes Specialities Centre, WHO Collaborating Centre for Non-Communicable Diseases-Prevention and Control and IDF Centre of Education, Gopalapuram, Chennai, India.
Anjana
Ranjit Mohan
RM
Unnikrishnan
Ranjit
R
Ganesan
Anbazaghan
A
Mohan
Vishwanathan
V
Rema
Mohan
M
D000328:Adult; D000375:Aging; D000419:Albuminuria / Q000652:urine; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications* / Q000473:pathology / Q000652:urine; D017719:Diabetic Foot / Q000150:complications / Q000453:epidemiology; D003928:Diabetic Nephropathies / Q000150:complications / Q000453:epidemiology* / Q000652:urine; D003929:Diabetic Neuropathies / Q000150:complications / Q000453:epidemiology*; D003930:Diabetic Retinopathy / Q000150:complications / Q000453:epidemiology* / Q000473:pathology; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007194:India / Q000453:epidemiology; D008297:Male; D055806:Microvessels / Q000473:pathology / Q000503:physiopathology; D015995:Prevalence; D012372:ROC Curve; D012307:Risk Factors; D012720:Severity of Illness Index; D014280:Triglycerides / Q000097:blood
D006442:Glycated Hemoglobin; D014280:Triglycerides; C517652:hemoglobin A1c protein, human