P1.22 REDUCED BAROREFLEX-SENSITIVITY IS NOT RELATED TO INCREASED CAROTID ARTERY STIFFNESS IN PATIENTS WITH SCHIZOPHRENIA

Abstract

Objectives: Baroreflex function was found to be impaired in schizophrenia and reduced baroreflex-sensitivity (BRS) was associated with increased mortality. Stiffening of the baroreceptor vessel wall, such as the carotid artery, may lead to reduced activation of the baroreceptors and blunt the baroreflex. We tested the hypothesis that reduced BRS is associated with increased carotid artery stiffness in schizophrenic patients. Methods: 24 first-episode schizophrenic patients and 24 age- and gender-matched controls were enrolled. Carotid artery was examined by echo wall-tracking and tonometry. Carotid artery distensibility coefficient (DC) and stiffness index β (Stiffness β) were calculated. ECG and beat-to-beat blood pressure recordings were used to determine BRS (BRSsp). Results: DC was reduced, Stiffness β was increased in patients compared with controls (3.90±0.96* vs. 5.06±0.98 10−3/mmHg; 6.15±1.49* vs. 5.01±1.02). BRSsp was reduced in patients compared with controls (9.42±6.88* vs. 22.27±7.50 ms/mmHg). No relation was found between the BRSsp and the carotid elastic parameters in patients, but BRSsp was related to carotid DC in healthy controls (r=0.67*). (mean±SD; *:p<0.05) Conclusions: Carotid artery distensibility is markedly reduced in schizophrenic patients. It has been shown that schizophrenia was associated with increased oxidative stress which may explain stiffening of the elastic vessel wall. The increased carotid artery stiffness does not play a dominant role in the reduction in BRS in schizophrenic patients. It appears that the attenuation of baroreflex may be due to damaged neural elements of the reflex arch. P1.23 Withdrawn by author