Increase in Nocturnal Blood Pressure and Progression to Microalbuminuria in Type 1 Diabetes

Background Patients with type 1 diabetes mellitus and microalbuminuria often have elevated blood pressure while they are asleep, but it is not known whether the elevation develops concomitantly with microalbuminuria or precedes it. Methods We monitored 75 adolescents and young adults who had had type 1 diabetes with normal urinary albumin excretion and blood pressure for more than five years. Ambulatory blood-pressure monitoring was used to assess blood pressure at the initial evaluation and about two years later, at which time all subjects had normal urinary albumin excretion. Subsequently, subjects were monitored for the development of microalbuminuria. Results Microalbuminuria developed in 14 subjects, whereas the other 61 continued to have normal urinary albumin excretion. The mean (±SD) systolic pressure during sleep increased significantly in the subjects who ultimately had microalbuminuria (from 109.9±11.3 to 114.9±11.7 mm Hg, P=0.01) but not in the subjects with normal albumin excretion (from 106....