Investigators with the goal of optimizing glycemic and blood pressure control saw type 1 diabetic patients weekly. A control group received 3-4 subcutaneous insulin injections per day; an intravenous insulin pulsed infusion group received, in addition, three one hour infusions in a pulsatile fashion over one eight hour period each week. Patients were followed for 12 months with periodic testing of renal function by repeated blood and urinary analyses; diabetes control by blood testing and diabetes impact measurement score; cardiac and autonomic function by echocardiography, 24 hour electrocardiographic testing; and visual changes with repeated fundus photography. The study hypothesis was that correction of respiratory quotient would correct the defect leading to microvascular complications of diabetes (Type 1).