Microalbuminuria as surrogate endpoint in therapeutic trials.

A surrogate endpoint is a measure of the effect of a certain treatment that may correlate with a real clinical endpoint but does not necessarily have a guaranteed relationship. The concept is particularly useful in cardiovascular and renal disease. We review evidence regarding microalbuminuria as one potential surrogate endpoint. In diabetes, hypertension and high cardiovascular risk, recent studies have demonstrated the prognostic value of significant changes in urinary albumin excretion for cardiovascular and renal outcomes. The most appropriate timing with which to repeat microalbuminuria and whether or not changes should be targeted during the antihypertensive treatment remain unanswered.