title: Increased sympathetic and decreased parasympathetic cardiac innervation in patients with Alzheimer's disease.
abstract: To assess whether Alzheimer's disease affects the sympathetic and parasympathetic influences on the heart rate, we used power spectrum analysis of heart rate variability derived from simple body-surface electrocardiography. We calculated the energy ratio of low- to high-frequency bands. This ratio was significantly higher in patients with Alzheimer's disease than in normal controls (upright posture, 0.41 +/- 0.21 vs 0.23 +/- 0.08). The parasympathetically mediated baroreceptor activity reflected by the energy ratio of medium- to low- and high-frequency bands was significantly depressed in patients with Alzheimer's disease (upright posture, 0.12 +/- 0.02 vs 0.07 +/- 0.03; supine posture, 0.11 +/- 0.02 vs 0.085 +/- 0.025). Compared with normal volunteer controls, patients with Alzheimer's disease manifested a relatively hypersympathetic, hypoparasympathetic state.
authors.affiliation: Department of Neurology, Rambam Medical Center, Haifa, Israel.
authors.forename: J
authors.initials: J
authors.lastname: Aharon-Peretz
authors.forename: T
authors.initials: T
authors.lastname: Harel
authors.forename: M
authors.initials: M
authors.lastname: Revach
authors.forename: S A
authors.initials: SA
authors.lastname: Ben-Haim
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000503:physiopathology*; D006321:Heart / Q000294:innervation*; D006339:Heart Rate; D006801:Humans; D010275:Parasympathetic Nervous System / Q000503:physiopathology*; D013564:Sympathetic Nervous System / Q000503:physiopathology*