[Arterial hypertension, stress, and beta-blockers].
There is strong circumstantial evidence supporting the hypothesis that essential arterial hypertension is associated at least initially, with an augmented sympathetic activity. The link between the sympathetic nervous system and the hypertensive state is further supported by the clinical evidence furnished by the efficacy of drugs interfering with sympathetic control. In this lecture we address the role of behavioral and mental factors, globally indicated with the word "stress", that may contribute to the initiation and maintenance of the hypertensive condition. At the core of this approach, there is the view that, operationally, mental stress could be conveniently substituted by some quantification of the sympathetic activity (in its continuous balance with vagal modulation). In our laboratory we employ the normalized power of the low frequency (LF, 0.1 Hz) component of the autospectra of RR interval variability as an index of sympathetic drive. In hypertensives at rest there is a prevalence of LF (as compared to the HF, high frequency, component, which is a marker of vagal activity). Additionally the responsiveness to both physical and mental stimuli is diminished. After chronic beta-adrenergic blockade, the spectral profile, and its responsiveness, returns toward normal. Furthermore the gain of baroreflex mechanisms (obtained with cross spectral analysis of RR interval and systolic arterial pressure variability) is also increased by atenolol treatment. We conclude that this approach may permit a better quantification of the role played by behavioral and mental factors in essential hypertension, and help to define individualized treatments.
Pagani
M
M
Medicina Interna II, Università degli Studi, Ospedale L Sacco, Milano.
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000209:etiology* / Q000503:physiopathology; D013312:Stress, Physiological / Q000503:physiopathology*
D000319:Adrenergic beta-Antagonists
Ipertensione arteriosa, stress e betablocco.