The pressor response to exercise and stress in uncomplicated insulin-dependent diabetes

We investigated whether or not an increased pressor response to exercise or stress is a feature of the diabetic state per se or a feature of its complications was investigated. Twelve insulin-dependent diabetic patients without clinical evidence of complications and with normal albumin excretion rates (less than 20 micrograms/min) were studied together with 12 matched control subjects. Each underwent a study protocol of isometric handgrip exercise at 30% of maximum capacity for four minutes, a cold pressor test with immersion of one hand in ice-cold water for two minutes, and bicycle ergometry at a resistance of 105 watts per minute for six minutes. The tests were undertaken in the same order in all subjects. There was, in both groups, a similar and significant rise in systolic blood pressure and pulse rate in response to each stimulus. Diastolic pressure also rose significantly in response to handgrip exercise and to cold pressor stimulation, but fell slightly during bicycle ergometry in both groups. Mean plasma noradrenaline concentration rose in response to each stimulus but the changes reached conventional significance in both groups only in response to handgrip exercise. Pressor responses to exercise and stress, as tested here, are concluded to be normal in insulin-dependent diabetic patients without complications due to their disease.