Control of Hyperglycemia in Adult Diabetics by Pulsed Insulin Delivery

Abstract

Nine adult diabetic subjects were treated for two weeks by an intravenous insulin-delivery system that provided preprogramed five-hour pulses of insulin with each meal such that a normal diurnal pattern of plasma insulin was attained. Plasma insulin peaked at 800 per cent of basal and at approximately 45 minutes after the onset of each pulse. On day 14, mean plasma glucose (hourly sampling × 22) was 94 mg./100 ml., with a range of 66 to 125 mg./100 ml. Eighty-eight per cent of all values were between 50 and 150 mg./100 ml. The dose of insulin required correlated significantly with the degree of obesity. On the first posttreatment day, hourly plasma glucose remained significantly below pretreatment levels while the endogenous plasma insulin area increased 46 per cent above pretreatment values (p < 0.01). Six of the patients still exhibited slight improvement in glucose tolerance for seven days while on diet but not on insulin treatment. It is concluded that insulin replacement, coordinated with meals in a physiologic manner, can virtually normalize plasma glucose even without feedback control of delivery rates. Definite but transient remission of beta-cell dysfunction may follow.