Quantification of cardiorespiratory coupling in acute schizophrenia applying high resolution joint symbolic dynamics

Schizophrenia is one of the most serious mental illnesses in the world. For schizophrenia an impaired cardiac autonomic function could be demonstrated in different studies. However, respiration as an important part in body's homeostatic control mechanisms in order to maintain a constant internal environment was given little attention especially to the corresponding cardiorespiratory regulation. The aim of this study was to quantify short-term cardiorespiratory couplings (CRC) in acute schizophrenia applying the high resolution joint symbolic dynamics (HRJSD) analysis approach. In this study, 23 unmedicated patients with acute schizophrenia (SZO; 12 male; 30.4±10.3 years) and 23 age-and gender matched healthy controls (CON, 13 male; 30.3±9.5 years) were investigated. HRJSD revealed for SZO in comparison to CON a significantly altered and widely distributed CRC (p<0.01) that was mainly characterized by a larger amount of increased short-term alternating and fluctuating patterns. Further on, the respiratory regulation seems to be more complex in SZO and dominates the CRC. These results indicate to an impairment of short-term respiratory regulation probably due to an impaired or suppressed interplay of the brainstem and higher regulatory centres in SZO.