REDUCED DECREASE OF PERIPHERAL VASCULAR-RESISTANCE DURING EXERCISE INYOUNG TYPE-I DIABETIC-PATIENTS

OBJECTIVE - In normal subjects, peripheral vascular resistance decreas es during dynamic exercise. We studied blood pressure and peripheral v ascular resistance responses to dynamic exercise in young normotensive type I diabetic patients. RESEARCH DESIGN AND METHODS - Thirty adoles cent diabetic patients (9-19 years of age) underwent a maximal exercis e test on a cycle ergometer. In a subset of 14 patients, cardiac outpu t was measured by a CO2 rebreathing method and peripheral vascular res istance was calculated Twenty-four normal individuals, age and sex mat ched, served as control subjects. RESULTS - Diastolic blood pressure w as significantly higher in diabetic patients at intermediate workload (77 +/- 2 vs. 71 +/- 1 mmHg) and peak exercise (86 +/- 2 vs. 73 +/- 2 mmHg). Peripheral vascular resistance was significantly higher in diab etic patients at intermediate workload (17.0 +/- 1.1 vs. 12.6 +/- 0.5 mmHg . l(-1) . min(-1) . m(-2)) and peak exercise (16.3 +/- 1.3 vs. 11 .4 +/- 0.5 mmHg . l(-1) . min(-1) . m(-2)). There were no significant correlations with the patient's age, diabetes duration, or diabetes co ntrol. CONCLUSIONS - We observed the decrease of vasodilator response during dynamic exercise in normotensive young type I diabetic patients .