Which anthropometric parameter is best related with urinary albumin excretion and creatinine clearance in type 2 diabetes: body mass index, waist circumference, waist-to-hip ratio, or conicity index?
OBJECTIVE
We analyzed the relationships between body mass index (BMI), waist circumference (WC), waist-to-hip ratio, and conicity index and 24-hour urinary albumin excretion rate (UAER) and creatinine clearance.


DESIGN
Cross-sectional study.


SETTING
Patients presenting to a state hospital.


PATIENTS
Study involved patients with type 2 diabetes.


METHODS
Study participants underwent medical history examination, measurement of office blood pressure (BP), measurement of anthropometric factors and calculations (including BMI, WC, waist-to-hip ratio, and conicity index), physical examination, biochemical analysis, and 24-hour urine specimen collection to determine creatinine clearance and UAER.


RESULTS
In all, 202 patients with type 2 diabetes (male/female: 91/111, aged: 58.4 ± 10.1 years) were included. It was found that 24-hour UAER correlated with WC (rho: +0.176, P = .012), serum albumin (rho: -0.324, P < .0001), and systolic BP (rho: +0.153, P = .029), whereas creatinine clearance correlated with age (rho: -0.152, P = .031), BMI (rho: +0.191, P = .007), albumin level (rho: +0.365, P < .0001), and uric acid level (rho: -0.369, P < .0001). The stepwise linear regression analysis revealed that WC (P = .012), glycosylated hemoglobin (P = .018), and systolic BP (P = .043) were found to be independently related to logarithmically converted 24-hour UAER, whereas creatinine clearance was found to be related to duration of diabetes (P = .001), BMI (P = .008), presence of peripheral arterial disease (P = .021), fasting serum glucose level (P = .003), and uric acid level (P < .0001). However, after correction for body surface area, BMI was no longer associated with creatinine clearance.


CONCLUSION
Among the anthropometric parameters, only an increase in WC was found to be independently related to 24-hour UAER. Although BMI was associated with creatinine clearance, this association was lost after creatinine clearance was corrected for body surface area.