Endothelial vasoregulation and mechanosensitive ion channels in hypertension

Background. Microalbuminuria, i.e. a subclinical increase of the albumin excretion rate in urine, may be a novel atherosclerotic risk factor. This study aimed to test whether microalbuminuria can be identified by measurement of urinary albumin concentration or urinary albumin/creatinine concentration ratio, instead of the usual measurement of the albumin excretion rate in a timed urine collection. Methods. All 2579 subjects analysed were screened in a population based epidemiological study. Participants with diabetes mellitus, renal disease, haematuria, or urinary tract infection were not included. Urinary albumin (U alb ) and creatinine (U creat ) concentrations were measured in an overnight collected sample by enzyme-linked immunosorbent and colorimetric assays, respectively. Urinary albumin excretion rate ( UAER) and urinary albumin/creatinine concentration ratio (U alb /U creat ) were calculated. Results. The correlation between U alb and UAER was 0.72 (n =2579, P<0.001), and the correlation between U aib /U creat and UAER was 0.81 (n = 2579, P<0.001). In the detection of microalbuminuria, the nosographic sensitivity and specificity, and the diagnostic specificity were 58%, 97%, and 66% for U alb , and 73%, 97%, and 73% for U alb /U creat , respectively. Conclusions. It is concluded that measurement of the albumin/creatinine concentration ratio is a specific and quite sensitive alternative to measurement of the urinary albumin excretion rate in timed collections, when screening for microalbuminuria.