Prevalence and risk factors of diabetic nephropathy in an urban South Indian population: the Chennai Urban Rural Epidemiology Study (CURES 45).
OBJECTIVE
The aim of this study was to determine the prevalence of diabetic nephropathy among urban Asian-Indian type 2 diabetic subjects.


METHODS
Type 2 diabetic subjects (n = 1,716), inclusive of known diabetic subjects (KD subjects) (1,363 of 1,529; response rate 89.1%) and randomly selected newly diagnosed diabetic subjects (NDD subjects) (n = 353) were selected from the Chennai Urban Rural Epidemiology Study (CURES). Microalbuminuria was estimated by immunoturbidometric assay and diagnosed if albumin excretion was between 30 and 299 microg/mg of creatinine, and overt nephropathy was diagnosed if albumin excretion was > or = 300 microg/mg of creatinine in the presence of diabetic retinopathy, which was assessed by stereoscopic retinal color photography.


RESULTS
The prevalence of overt nephropathy was 2.2% (95% CI 1.51-2.91). Microalbuminuria was present in 26.9% (24.8-28.9). Compared with the NDD subjects, KD subjects had greater prevalence rates of both microalbuminuria with retinopathy and overt nephropathy (8.4 vs. 1.4%, P < 0.001; and 2.6 vs. 0.8%, P = 0.043, respectively). Logistic regression analysis showed that A1C (odds ratio 1.325 [95% CI 1.256-1.399], P < 0.001), smoking (odds ratio 1.464, P = 0.011), duration of diabetes (1.023, P = 0.046), systolic blood pressure (1.020, P < 0.001), and diastolic blood pressure (1.016, P = 0.022) were associated with microalbuminuria. A1C (1.483, P < 0.0001), duration of diabetes (1.073, P = 0.003), and systolic blood pressure (1.031, P = 0.004) were associated with overt nephropathy.


CONCLUSIONS
The results of the study suggest that in urban Asian Indians, the prevalence of overt nephropathy and microalbuminuria was 2.2 and 26.9%, respectively. Duration of diabetes, A1C, and systolic blood pressure were the common risk factors for overt nephropathy and microalbuminuria.
Unnikrishnan
Ranjit I
RI
Madras Diabetes Research Foundation and Dr. Mohan's Diabetes Specialities Centre, 4 Conran Smith Rd., Gopalapuram, Chennai, 600 086, India.
Rema
Mohan
M
Pradeepa
Rajendra
R
Deepa
Mohan
M
Shanthirani
Coimbatore Subramaniam
CS
Deepa
Raj
R
Mohan
Viswanathan
V
D000328:Adult; D000368:Aged; D000419:Albuminuria / Q000453:epidemiology; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000453:epidemiology*; D003928:Diabetic Nephropathies / Q000453:epidemiology*; D003930:Diabetic Retinopathy / Q000453:epidemiology; D005260:Female; D006801:Humans; D007194:India / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D014505:Urban Population