Abstract
Albumin concentration of the first morning urine, with and without creatinine correction, was compared with overnight and 24-hour albumin excretion rates, in hospitalized patients in whom urine collection could be timed precisely. Subjects were 24 patients with IDDM who had no proteinuria by Albustix. Albumin concentration on the first morning correlated closely with the overnight albumin excretion rate (r=0.84) and the 24-hour albumin excretion rate (r=0.79). Albumin per creatinine ratio of the first urine in the morning correlated closely with the overnight albumin excretion rate (r=0.93) and the 24-hour albumin excretion rate (r=0.68). These findings suggest that creatinine correction is not needed for the first morning urine to express microalbuminuria. Since the albumin concentration of the first urine in the morning is not subject to water dilution and exercise load, we conclude that this concentration is useful for the follow-up of microalbuminuria.
