The Prevalence, Risk Factors and Clinical Correlates of QTc Prolongation in Chinese Hospitalized Patients With Chronic Schizophrenia

Risk of corrected QT interval prolongation in patients receiving antipsychotics

Antipsychotic (AP) use has been associated to QT interval prolongation on the surface electrocardiogram (ECG). Our study aimed to determine the incidence of corrected QT (QTc) interval prolongation among patients admitted to a psychiatric hospitalization unit requiring AP treatment and to assess the relationship between administered dose and QTc interval changes. We enrolled 179 patients admitted to the Hospital Psiquiátrico Departamental Universitario del Valle in Cali, Colombia. ECGs were conducted upon admission, and again at 3 and 7 days postadmission. The QT interval was measured, and QTc interval correction was performed using Bazzet's formula. QTc interval prolongation at time points B or C was observed in 9.5% of patients. Clozapine was the most common AP associated with QTc interval prolongation (20.59%), followed by olanzapine (15.38%). The relative risk of QT interval prolongation with clozapine compared to haloperidol was 4.17 (95% confidence interval, 1.14-15.17, P  = 0.02). AP use upon hospital admission was linked to early (within 3 days) QTc interval prolongation. Clozapine and olanzapine were associated with a greater increase in QTc interval compared to haloperidol, indicating a need for rigorous electrocardiographic monitoring with their use.

QTc interval changes among patients on psychotropic medications: A prospective observational study

Background

Psychotropic medications are commonly prescribed for the treatment of psychiatric disorders. Various studies have reported QT interval (QTc) prolongation with the use of psychotropics. However, some studies have found no significant risk of QTc changes with these medications.

Aim

To assess the effect of psychotropics on QTc in drug-naive psychiatric patients.

Materials and Methods

Our study was a prospective observational study, conducted at a tertiary care hospital. Patients aged 18-45 years, drug-naïve, with no medical comorbidity or substance use history, were recruited for the study. ECG to assess QTc was recorded at baseline, second and fourth week after the starting of psychotropic medications.

Results

N=8 (4%) patients had QTc prolongation at baseline and were excluded. No clinically significant QTc prolongation was noticed, after 2 weeks and 4 weeks of treatment with any of the psychotropic medications. However, among patients on escitalopram, a significant effect on QTc was noted (P = 0.001) as compared to those on sertraline, risperidone, and olanzapine (P > 0.05).

Conclusion

The short-term risk of QTc prolongation with the use of newer psychotropics at optimal doses appears low among young patients with normal baseline QTc and no significant medical or substance use comorbidity.

QTc prolongation in patients with schizophrenia taking antipsychotics: Prevalence and risk factors

BACKGROUND

QTc prolongation is one of the possible complications in patients with schizophrenia taking antipsychotics, which leads to malignant cardiac arrhythmia. No meta-analysis has been reported assessing the prevalence and correlated risk factors for QTc prolongation.

METHODS

This meta-analysis aimed to assess the evidence for the prevalence of QTc prolongation and correlated risk factors in patients with schizophrenia taking antipsychotics. Web of Science and PubMed were searched according to preset strategy. The quality of research was assessed by the Newcastle-Ottawa Scale (NOS).

RESULTS

In all, 15 studies covering 15,540 patients with schizophrenia taking antipsychotics were included. Meta-analysis showed that the prevalence of QTc prolongation in patients with schizophrenia taking antipsychotics was about 4.0% (95% confidence interval (CI): 3.0%-5.0%, p < 0.001). The prevalence was about 4.0% in Asia (95%CI: 3.0%-6.0%, p < 0.001), about 5.0% in Europe (95%CI: 2.0%-7.0%, p < 0.001), and about 2.0% in America (95%CI: 1.0%-3.0%, p < 0.001). Sensitivity analyses indicated the robustness of the result. Publication bias analysis reported a certain publication bias (t = 3.37, p = 0.012). Meta-regression suggested that female and elderly patients were clinically associated with a higher prevalence of QTc prolongation. According to included studies, smoking, comorbidity of cardiovascular disease, and abnormal levels of high-density lipoprotein/low-density lipoprotein might be related to QTc prolongation in patients with schizophrenia taking antipsychotics.

CONCLUSIONS

The prevalence of QTc prolongation in patients with schizophrenia taking antipsychotics was about 4.0%. Female and elderly patients were more likely to experience QTc prolongation. Close electrocardiogram monitoring was suggested in these at-risk populations.

Abnormal blood lipid and electrocardiogram characteristics in common mental disorders

BACKGROUND

At present, there is not enough evidence to prove the relationship between blood lipid and electrocardiogram (ECG) abnormalities in common mental disorders (CMD). This study aimed to explore the relationship between them, to detect and prevent arrhythmia or sudden death.

METHODS

We collected 272 CMD patients (maintained a fixed drug dose pattern for 1 year or more), including 95 schizophrenias (SC), 90 bipolar disorders (BD) and 87 major depressive disorders (MDD), and 78 healthy controls (HC) from the Third People's Hospital of Foshan, China. We analyzed and compared their blood lipid and ECG indicators, to clarify the relationship between them.

RESULTS

350 participants were included. There were no significant differences in age, gender, total cholesterol (TC), low density lipoprotein (LDL) and QTc (p > 0.05) among subjects. And there were significant differences in body mass index (BMI), triglyceride (TG), high density lipoprotein (HDL), heart rate, PR interval and QRS width (p < 0.05). Person correlation analysis showed that QRS width was positively correlated with BMI and TG. And negatively correlated with HDL. Meanwhile, QTc was positively correlated with BMI. Multiple linear regional analysis further proved that TG (B = 3.849, p = 0.007) and LDL (B = 11.764, p = 0.018) were the risk factors, and HDL (B = -9.935, p = 0.025) was the protective factor for QRS width increase.

CONCLUSION

Long term medication of CMD patients should strengthen weight management, and conduct regular blood lipid and ECG examinations to achieve early detection and intervention in order to promote their health.

Determinants of severe QTc prolongation in a real-world gerontopsychiatric setting

Introduction

QT_c prolongation carries the risk of ventricular tachyarrhythmia (Torsades de Pointes) and sudden cardiac death. Psychotropic drugs can affect ventricular repolarization and thus prolong the QT_c interval. The present study sought to investigate the risk factors (pharmacological and non-pharmacological) of severe QT_c prolongation in gerontopsychiatric patients.

Methods

Electrocardiograms of patients on a gerontopsychiatric ward were screened for QT_c prolongation. Medication lists were examined utilizing the AzCERT classification. Potential drug interactions were identified with the electronic drug interaction program mediQ.

Results

The overall prevalence of QT_c prolongation was 13.6%, with 1.9% displaying severe QT_c prolongation (≥ 500 ms). No statistically significant differences between patients with moderate and severe QT_c prolongation were identified; however, patients with severe QT_c prolongation tended to take more drugs (p = 0.063). 92.7% of patients with QT_c prolongation took at least one AzCERT-listed drug, most frequently risperidone and pantoprazole. Risperidone and pantoprazole, along with pipamperone, were also most frequently involved in potential drug interactions. All patients displayed additional risk factors for QT_c prolongation, particularly cardiac diseases.

Conclusion

In addition to the use of potentially QT_c-prolonging drugs, other risk factors, especially cardiac diseases, appear to be relevant for the development of QT_c prolongation in gerontopsychiatric patients. Pantoprazole was frequently involved in potential drug interactions and should generally not be used for more than 8 weeks in geriatric populations. As clinical consequences of QT_c prolongation were rare, potentially QT_c-prolonging drugs should not be used overcautiously; their therapeutic benefit should be considered as well. It is paramount to perform diligent benefit-risk analyses prior to the initiation of potentially QT_c-prolonging drugs and to closely monitor their clinical (side) effects.

Clozapine Blood Concentration Predicts Corrected QT-Interval Prolongation in Patients With Psychoses

BACKGROUND

Corrected QT-interval (QTc) prolongation (QTP) is a rare but fatal adverse effect of antipsychotics. Clozapine is the only antipsychotic recommended for treatment of resistant schizophrenia; however, clozapine has been reported to cause QTP. We sought factors predictive of QTP in patients who had antipsychotic polypharmacy involving clozapine. We explored whether the clozapine blood concentration might predict QTP.

METHODS

We included 133 patients with schizophrenia spectrum disorder who had antipsychotic polypharmacy involving clozapine. We used the χ2 and nonparametric tests to compare clozapine therapeutic drug monitoring (TDM) values and QTc-prolonged person (QTPP) status. Multivariate regression and mediator models were used to identify risk factors for QTPP status and QTP.

RESULTS

In total, 111 patients were prescribed clozapine. The QTPP rates were 31.3% (20) for men and 23.2% (16) for women. Compared with the non-QTPP group, the QTPP group exhibited significantly higher daily dose of all antipsychotics including clozapine, a higher clozapine dose, and elevated clozapine and norclozapine TDM values. Furthermore, such patients were prescribed a greater number of antipsychotics. Multivariate logistic regression revealed that only the clozapine TDM value could be predictive factor for QTPP status (P = 0.018). A clozapine TDM value above the therapeutic range (>600 mg/dL) was associated with a high risk of QTPP status (adjusted odds ratio, 6.5; 95% confidence interval, 1.7-25.2; P = 0.006). The mediator model revealed that the clozapine TDM values completely mediated the association between the clozapine dose and the QTc interval.

CONCLUSIONS

The clozapine blood concentration reliably predicts QTP in patients with clozapine use.