Comparison of albuminuria test and urine test strip in Japanese hypertensive patients: AVA-E study

Background: Albuminuria is thought to reflect generalized endothelial dysfunction. In hypertensive patients, albuminuria is related to the risk for cardiovascular disease (CVD) events. Thus, screening for albuminuria is critical for risk stratification in hypertensive patients. However, the actual state of albuminuria in Japanese patients without diabetes remains unclear due to insurance coverage. Methods: The CLINITEK microalb creatinine test® is a urine test paper that can assess albumin excretion corrected for urine creatinine levels in only 60 seconds without any special equipment. The semi-quantitative albuminuria test and urine proteinuria test were performed on 8,181 Japanese hypertensive patients, and the clinical significance of the test was evaluated by comparison with the urine test strip method. Results: Albumin creatinine ratio (ACR) < 30 mg/g creatinine, ACR 30 - 299 mg/g creatinine, and ACR = 300 mg/g creatinine on the albuminuria test were present in 70.0%, 25.7%, and 4.3%, respectively, of patients with a negative urine protein test strip result. Furthermore, in patients with a negative urine protein test strip result, ACR = 30 mg/g creatinine was independently associated with previous CVD (odds ratio: 1.25, 95% confidence interval: 1.00 - 1.57, p < 0.05) after adjustment for estimated glomerular filtration rate, age, sex, BMI, smoking, dyslipidemia, diabetes, and blood pressure categories on multivariate logistic regression analysis. Conclusions: We considered that urine test strip was inadequate test to evaluate albuminuria. Easy and quick albuminuria test on the CLINITEK microalb creatinine test might be useful test to risk stratification of hypertensive patients compared to urine test strip.