Prediction of cardiovascular events, diabetic nephropathy, and mortality by albumin concentration in a spot urine sample in patients with type 2 diabetes.
OBJECTIVE
To analyze in a random urine spot the predictive value of urinary albumin concentration (UAC) for cardiovascular events, diabetic nephropathy (DN), and death in patients with type 2 diabetes.


METHODS
In this cohort, urinary albumin (immunoturbidimetry) was measured as 24-h urinary albumin excretion (UAE) and, in a random spot urine, as UAC and albumin:creatinine ratio (ACR). Primary outcomes were: 1) cardiovascular events, 2) DN defined as a composite outcome [macroalbuminuria and/or decreased glomerular filtration rate (GFR) <60 ml/min/1.73 m²], and 3) death.


RESULTS
A total of 199 type 2 diabetic patients, aged 59.9 ± 9.9 years, were followed for 6.1 ± 2.7 years. UAC ≥14.4 mg/l, as determined by ROC curve, predicted DN and prediction for this and other outcomes were compared with traditional microalbuminuria cutoffs for ACR and UAE. The outcomes frequency was: cardiovascular events = 26.4%, DN = 31.7% (23.5% decreased GFR; 13.6% macroalbuminuria) and death = 8.50%. In Cox analyses, UAC ≥14 mg/l increased the risk (hazard ratio, HR) for cardiovascular events 3.25 times (95% CI 1.43-7.38; P = 0.005), 4.30 for DN composite outcome (95% CI 2.22-8.32; P <0.001), and 5.51 for death (95% CI 1.16-26.22; P = 0.032). Corresponding HRs of ACR ≥30 mg/g were: 2.89 (95% CI 1.29-6.45; P = 0.009) for cardiovascular events, 4.67 (95% CI 2.34-9.34; P <0.001) for DN composite outcome and 5.07 (95% CI 1.01-24.88; P = 0.049) for death. HRs of UAE ≥30 mg/24-h were: 2.20 (95% CI 2.08-2.49; P = 0.030) for cardiovascular events, 6.76 (95% CI 3.32-13.77; P <0.001) for DN composite outcome, and 2.47 (95% CI 0.72-8.42; P = 0.150) for death.


CONCLUSIONS
In conclusion, random UAC ≥14 mg/l predicted cardiovascular events, diabetic nephropathy, and mortality just as well as ACR. UAC may be used to assess cardiovascular and renal risks in patients with type 2 diabetes.
Endocrine Division, Hospital de Clínicas de Porto Alegre, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
Luciana Verçoza
LV
Viana
Jorge Luiz
JL
Gross
Joiza Lins
JL
Camargo
Themis
T
Zelmanovitz
Enio P C
EP
da Costa Rocha
Mirela Jobim
MJ
Azevedo
D000368:Aged; D000419:Albuminuria / Q000150:complications*; D001938:Brazil / Q000453:epidemiology; D002318:Cardiovascular Diseases / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000401:mortality* / Q000652:urine*; D003925:Diabetic Angiopathies / Q000175:diagnosis* / Q000453:epidemiology; D058065:Diabetic Cardiomyopathies / Q000175:diagnosis* / Q000453:epidemiology; D003928:Diabetic Nephropathies / Q000175:diagnosis* / Q000453:epidemiology; D042241:Early Diagnosis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009026:Mortality; D010044:Outpatient Clinics, Hospital; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011934:Reagent Strips; D012306:Risk; D016019:Survival Analysis
D011934:Reagent Strips