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Background: People of South Asian origin are at high risk of chronic kidney disease. Some have suggested that the usual level of glomerular filtration rate (GFR) in South Asians may be lower than in populations of European origin. However, measured GFR in a general adult population of South Asian origin has not been studied., Design: Cross-sectional observational study., Setting & Participants: 530 patients 40 years or older randomly selected from communities in Karachi, Pakistan, using multistage cluster sampling. Patients with both diabetes and hypertension were excluded., Predictor: Age, sex, diabetes, and hypertension., Outcome: Measured GFR using urinary clearance of inulin., Results: Mean age of participants was 49.7 ± 9.5 (standard deviation [SD]) years, 51% were men, 34.9% had hypertension, and 30.5% had diabetes. Mean measured GFR was 94.1 ± 28.6 mL/min/1.73 m(2). GFR was lower by 0.79 ± 0.11 mL/min/1.73 m(2) for each 1-year older age. The 5-year age- and sex-specific mean GFR of the study population generally was within 1 SD of the mean of previously reported values for US adults. Factors independently associated with GFR were younger age (β coefficient, -3.84 [95% CI, -5.46 to -2.21] mL/min/1.73 m(2) per 5 years older), higher serum albumin level (4.58 [95% CI, 0.74-8.42] mL/min/1.73 m(2) per 0.5-g/dL increase), higher fasting plasma glucose level (0.81 [95% CI, 0.44-1.18] mL/min/1.73 m(2) per 10-mg/dL increase), high versus low meat intake (7.81 [95% CI, 1.14-14.48] mL/min/1.73 m(2) for ≥11 vs ≤5 servings/wk), and higher estimated protein intake (1.46 [95% CI, 0.41-2.51] mL/min/1.73 m(2) per 1.0-g/d increase) from urine urea nitrogen., Limitations: Moderate sample size, lack of validation of some items in the dietary assessment for this study population., Conclusions: Mean measured GFR in South Asian adults from the general population in Karachi, Pakistan, is only modestly lower than in European-origin counterparts, with similar age association. This may reflect lower dietary protein intake in South Asians., (Copyright © 2011 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Background: Albuminuria (>30 mg/day) based on 24 h urine albumin excretion is one of the criteria for chronic kidney disease (CKD) and a predictor of cardiovascular disease (CVD). Differences in urine albumin concentration and creatinine excretion rates between Indo-Asians and other populations may require different threshold values for detection of albuminuria. We compared the use of spot urine albumin concentration and urine albumin to creatinine excretion ratio for detection of albuminuria in this population., Methods: A total of 577 subjects aged >or=40 years, 54% of whom were women, were recruited from the general population in Karachi, Pakistan. Albumin concentration (mg/l) and albumin to creatinine ratio (mg/g of creatinine) were determined in a spot morning urine sample, and albuminuria (30 mg/day or greater) measured in a 24 h urine collected on the subsequent day., Results: The median (25-75 percentile) of urine albumin excretion was 4.8 (3.6-10.3) mg/day: 5.4 (3.7-12.5) mg/day in men and 4.5 (3.8-8.9) mg/day in women. The overall prevalence (95% CI) of albuminuria was 11.8% (7.2-12.0%): 14.8% in men and 9.2% in women (P = 0.04). The areas under the receiver operator characteristic (ROC) curves for urine albumin concentration were 0.86 (0.82-0.90) and 0.88 (0.84-0.92), respectively, in women and men. The areas under the ROC curves for albumin to creatinine ratio were 0.86 (0.82-0.89) and 0.90 (0.86-0.93), respectively, in women and men. For urine albumin concentration, the sensitivity and specificity were 37 and 97%, respectively, in women and 69 and 94%, respectively, in men at the conventionally recommended value of 2 mg/dl. The discriminator value of urine albumin concentration identified in the analysis was 0.5 mg/dl in women (sensitivity of 87% and specificity of 75%) and 1.7 mg/dl in men (sensitivity of 74% and specificity of 93%). For the albumin to creatinine ratio, the sensitivity and specificity were 46 and 95%, respectively, in women and 60 and 97%, respectively, in men at cut-off value of 30 mg/g., Conclusion: Both urine albumin concentration and albumin to creatinine ratio are acceptable tests for population screening for albuminuria in Indo-Asians. While sensitivities may be suboptimal, particularly in women, lowering the existing thresholds would compromise specificity. Those who screen positive need evaluation and management of CKD and prevention of CVD.