Effects of interferon on circadian changes in blood pressure and heart rate variability in patients with chronic hepatitis

We have determined the effects of interferon therapy on circadian changes i n blood pressure and heart rate variability in normotensive hospitalized pa tients with chronic active hepatitis. Body temperature and pulse rate incre ased for the initial few days of interferon therapy without significant cha nge in casual or ambulatory blood pressure. Interferon therapy failed to el icit any significant changes in the power spectrum of R-R intervals. In add ition, urinary excretion of norepinephrine did not differ between before an d during the therapy. These results suggest that interferon therapy caused transient increases in body temperature and pulse rate, but that it did not change either sympathetic or parasympathetic outflow, or the circadian rhy thm of blood pressure and heart rate variability, in normotensive subjects. (C) 1999 American Journal of Hypertension, Ltd.