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Published on: February 4, 2014
Blood Pressure and Heart Rate Changes During Clozapine Treatment
Sarah M Norman1, Kelli M Sullivan2, Fang Liu3
1University of Maryland School of Pharmacy, 20 N. Pine St, Baltimore, MD, 21201, USA.
Insights
Clozapine (CLZ) treatment for schizophrenia significantly increases diastolic blood pressure and heart rate. This medication may elevate blood pressure, increasing cardiovascular risks in patients.
Area of Science:
- Psychiatry
- Cardiology
- Pharmacology
Background:
- Individuals with schizophrenia face a 3-4 times higher risk of cardiovascular disease mortality.
- Clozapine (CLZ) is a crucial treatment for refractory schizophrenia.
- CLZ is linked to tachycardia, and emerging evidence suggests it may cause elevated blood pressure and hypertension.
Purpose of the Study:
- To investigate the impact of CLZ on blood pressure (BP) and heart rate (HR).
Main Methods:
- Retrospective chart review of 18 patients (18-75 years) diagnosed with Schizophrenia or Schizoaffective disorder.
- Assessed systolic blood pressure (SBP), diastolic blood pressure (DBP), and HR at 12 weeks pre-CLZ and 24 weeks during CLZ treatment.
- Analyzed changes in BP and HR relative to CLZ dosage and treatment duration.
Main Results:
- Diastolic blood pressure (DBP) and heart rate (HR) significantly increased post-CLZ initiation (p < 0.049 and p < 0.0001, respectively).
- A trend towards increased systolic blood pressure (SBP) was observed (p = 0.071).
- Hypertension prevalence rose from 22% to 67% during CLZ treatment (p = 0.0124).
Conclusions:
- CLZ treatment is associated with significant increases in DBP and HR, and a trend towards increased SBP.
- A substantial rise in hypertension incidence was noted during CLZ therapy.
- Further research is essential to identify risk factors and mechanisms underlying CLZ-induced cardiovascular side effects.
Abstract:
People with schizophrenia are 3-4 times more likely to die from cardiovascular disease than the general population. Clozapine (CLZ) is the gold standard of treatment for refractory schizophrenia. It has been associated with tachycardia and recent evidence shows individuals prescribed CLZ may develop blood pressure (BP) elevation and hypertension. The purpose of this study was to examine the effects of CLZ on BP and heart rate (HR). This was a retrospective chart review of patients 18-75 years old with a DSM IV diagnosis of Schizophrenia or Schizoaffective disorder. Primary outcomes were systolic blood pressure (SBP), diastolic blood pressure (DBP), and HR measured 12 weeks before and 24 weeks during CLZ treatment. Eighteen patient records were included in this study. The mean stabilized CLZ dose was 441.7 ± 171.8 mg/day. DBP (t = 1.02, df = 79.5, = 2.00, 0.049) and HR (t = 1.32, df = 355 = -4.61, < 0.0001) were significantly higher after CLZ initiation. A trend was noted for increase in SBP (p = 0.071). 22 % of patients met criteria for hypertension before CLZ and 67 % during CLZ treatment (Chi Square = 6.25, df = 1, p = 0.0124). No significant changes in weight or renal function occured during CLZ treatment. No patients had evidence of cardiomyopathy. The data suggest CLZ may be associated with a rise in BP and HR. The results of this study support previous literature that found an increase in SBP/DBP regardless of CLZ dose, occurring early in treatment. Due to high risk of cardiovascular morbidity and mortality, more work is needed to determine risk factors and understand the mechanism of action that may cause this side effect.
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