DIABETES MODIFIES CARDIOVASCULAR REACTIVITY DURING HYPERTENSION

Hypertension and diabetes often occur in the same patient, and this ob servation inspired the search for a new common pathogenetic hypothesis . The onset of diabetes during hypertension also could modify cardiova scular autonomic arousal. To identify a peculiar hemodynamic and psych ophysiologic reactivity, a male population of mild essential hypertens ive (166 +/- 6/102 +/- 8 mm Hg) patients (EH) and noninsulin-dependent hypertensive (169 +/- 10/101 +/- 7 mm Hg) diabetic subjects (HD) unde rwent a session of stress tests. Four tests, Mental Arithmetic, Incomp lete Phrases, Cold Presser, and Handgrip, were preceded and followed b y a 10-minute recovery period. Functional tests were performed to iden tify any possible cardiac autonomic neuropathy. During the entire sess ion, by means of a beat-to-beat noninvasive computerized device, hemod ynamic and extracardiovascular functions were measured. The findings s uggested the presence of a sympathetic hyperactivity in both HD and EH . In particular, HD showed a peculiar ''tropism'' for the peripheral v asculature. In these patients, in fact, total vascular resistance and peripheral temperature responses were 89.2% and -64.2%, respectively, versus 33.7% and -50.6%, which were found in EH. On the other hand, th e ejection ventricular index was more depressed in HD (-27.9%) than in EH (-23.8%), although they did not seem to be affected by cardiac aut onomic damage. The different profiles appear to confirm the increase o f functional vascular damage in diabetic hypertensive patients, probab ly because of the insulin resistance or obsolete muscular cardiac dama ge.