A Randomized, 8-Week Study of the Effects of Extended-Release Paliperidone and Olanzapine on Heart Rate Variability in Patients With Schizophrenia.

Purpose: This study aimed to explore the effect of extended-release paliperidone (paliperidone ER) and olanzapine on heart rate variability (HRV) in patients with schizophrenia.

Methods: A total of 106 patients with schizophrenia diagnosed by the Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) were randomly divided into the paliperidone ER group or the olanzapine group for an 8-week clinical trial, with 53 patients in each group. The time domain and frequency domain analyses including the SD of all the R-R intervals in 24 hours (SDNN), the SD of the mean value of all the normal R-R intervals in every 5-minute interval within 24 hours (SDANN index), the mean value of the SD of all the normal R-R intervals in every 5-minute interval within 24 hours (SDNN index), the root mean square of successive R-R differences, the percentage of adjacent R-R intervals that differ by more than 50 milliseconds, high-frequency power (HF), low-frequency power (LF), and LF/HF were adopted to assess the HRV of patients at baseline and after treatment for 8 weeks in each group. The Positive and Negative Symptom Scale was used to evaluate the clinical efficacy. The incidence rates of adverse reactions were also calculated.

Results: In total, 48 patients in the paliperidone ER group and 45 patients in the olanzapine group completed the entire 8-week treatment. The SDNN, SDNN index, and SDANN index in the olanzapine group were significantly lower than those in the paliperidone ER group (P < 0.05) after treatment for 8 weeks, whereas their mean LF level was higher than that in the paliperidone ER group (P < 0.05) after completion of treatment. Patients in the olanzapine group showed a significant decrease in the SDNN, SDANN index, and SDNN index as well as a statistical increase in the LF and LF/HF in comparison with the pretreatment values (P < 0.05), whereas patients in the paliperidone ER group showed a decrease in the SDANN index and a statistical increase in the LF in comparison with the pretreatment values (P < 0.05).

Conclusion: The HRV of patients with schizophrenia changes when they are administered with paliperidone ER or olanzapine, and more attention should be paid to their cardiac autonomic function when using these 2 antipsychotics.