Objective: Increased risk for arrhythmias and the association between arrhythmogenic markers and symptom severity in antipsychotic-free patients with schizophrenia are understudied. We evaluated the changes in P-wave dispersion (PWD), corrected QT interval (QTc), QTc dispersion (QTcd), corrected JT interval (JTc), JTc dispersion (JTcd), Tpeak-Tend (Tp-e), and Tp-e/QT ratio.
Method: Fifty-six patients with schizophrenia who were antipsychotic-free for at least 1 month and 56 age- and gendermatched healthy controls were included. Illness-related characteristics such as the Positive and Negative Syndrome Scale (PANSS) scores were recorded. Electrocardiography recordings were performed with standardized procedures for all participants, and risk markers of arrhythmia were calculated from the electrocardiograms.
Results: PWD (p<0.001), QTc (p<0.001), QTcd (p=0.002), JTc (p<0.001), and JTcd (p<0.001) values significantly increased in patients compared to the controls. Among the ECG markers, PWD was significantly and inversely correlated with the PANSS General subscale (r=-0.27, p<0.05), and JTc was correlated with age at illness onset (r=0.41, p=0.001).
Conclusion: Changes in ECG-derived markers of cardiac arrhythmia, which are acquired through an easy and cheap method, can be evaluated to predict and prevent serious cardiac conditions in antipsychotic-free schizophrenia patients.