Effects of six antipsychotic drug treatment regimens on short-term heart rate variability in patients with schizophrenia

ObjectiveMany antipsychotic drugs have cardiac side effects. Heart rate variability (HRV) analysis can be used as a indicator of cardiotoxicity in cases where a decrease in HRV occurs after the administration of antipsychotics such as clozapine. The purpose of this study was to explore the effects of 6 antipsychotic drug regimens on short-term HRV in patients with schizophrenia.MethodsData from 164 patients with schizophrenia between January 2018 and June 2023 were retrospectively analyzed. Based on the drug used for treatment, patients were categorized into clozapine combination (clozapine combined with aripiprazole, risperidone or ziprasidone), clozapine alone, olanzapine, aripiprazole, ziprasidone, and risperidone groups. Heart rate variability indices were calculated using time domain analysis, including the standard deviation of the RR intervals (SDNN), the root mean square of successive RR interval differences (RMSSD), and the percentage of successive RR intervals over 50 ms (PNN50).ResultsCompared with the pretreatment period, the SDNN, RMSSD, and PNN50 were significantly lower in the clozapine combination, clozapine, olanzapine and aripiprazole groups at the end of weeks 2 and 4 of treatment (<i>P</i> < 0.05). However, those indicators in ziprasidone and risperidone groups did not show this decrease (<i>P</i> > 0.05).ConclusionThe effects of clozapine combination and clozapine on HRV were greater than for olanzapine, aripiprazole, ziprasidone, or risperidone. Attention should be paid to controlling the dose of clozapine combination and clozapine alone and monitoring the patient's electrocardiogram during administration.