Hydroxychloroquine Inhibits Cardiac Conduction in Aged Patients with Nonmalaria Diseases

Area of Science:

• Cardiology
• Pharmacology
• Internal Medicine

Background:

• The COVID-19 pandemic heightened interest in hydroxychloroquine (HCQ) and its risk-benefit profile.
• Understanding HCQ's effects on cardiac function is crucial for patient safety.
• This study addresses the need for data on HCQ's cardiac implications in non-malaria patients.

Purpose of the Study:

• To evaluate the impact of hydroxychloroquine (HCQ) on cardiac conduction in non-malaria patients.
• To identify factors influencing HCQ's effects on electrocardiogram (ECG) parameters.
• To contribute to the global understanding of HCQ's cardiovascular risks.

Main Methods:

• Retrospective review of 717 non-malaria patients (302 HCQ, 415 controls) from 2008-2019.
• Analysis of electrocardiogram (ECG) data, including heart rate (HR), PR interval, and corrected QT (QTc) interval.
• Exploration of correlations between cardiac conduction and patient factors (age, sex, HCQ dosage/duration, primary disease).

Main Results:

• All-cause mortality was similar between HCQ and non-HCQ groups.
• Patients aged 45+ treated with HCQ showed lower HR but longer PR and QTc intervals compared to controls.
• In HCQ users, age positively correlated with PR and QTc intervals; no significant relation found with HCQ dosage, duration, sex, or primary disease.

Conclusions:

• Age is a significant risk factor for HCQ-associated changes in cardiac conduction among non-malaria patients.
• Electrocardiogram (ECG) monitoring is recommended for elderly patients receiving HCQ.
• HCQ's effects on heart rate, PR, and QTc intervals necessitate careful consideration in specific patient populations.