Cumulative dose of hydroxychloroquine is associated with a decrease of resting heart rate in patients with systemic lupus erythematosus: a pilot study

Abstract

CD-HCQ higher than 365 g was associated with a significant decrease (11%) in RHR in non-active SLE patients, although a larger prospective study is required to allow more definitive conclusions.

Suspected Hydroxychloroquine-Induced Sinus Bradycardia and QTc Prolongation in a Patient with COVID-19

“…However, it was reported to cause QT prolongation and decrease the resting HR. 3,4) Although such proarrhythmic effects were rarely seen and occurred usually after chronic use, we could not definitely exclude such a link in our patient based on a few acute cardiac toxicity cases with low doses of HCQ use, and the association between the normalization of the heart rhythm and QTc and the HCQ withdrawal further demonstrated that. A literature review revealed a case of recent onset of complete atrioventricular block just two days after HCQ initiation to treat systemic lupus erythematosus.…”

Short-term Hydroxychloroquine in COVID-19 Infection in People With or Without Metabolic Syndrome – Clearing Safety Issues and Good Clinical Practice

“…24,25 In absolute numbers, at doses of 5 mg/kg weight/day, the risk of retinal toxicity at 5, 10 and 20 years of use is 1%, 2% and 20%, respectively. 26 What is important to highlight, is that retinal toxicity primarily occurs with high-dose usage for prolonged periods. In a cohort of 123 patients with rheumatoid arthritis, It must be realised that hydroxychloroquine use is associated with reduction in heart rate and cardiomyopathy.…”

“…Animal studies in mice and guinea pigs have shown that hydroxychloroquine reduces heart rate by acting on the sino-atrial node and modulating the hyperpolarisation-activated current. 25 In a study involving 45 patients with lupus on long-term hydroxychloroquine therapy, 18 patients with cumulative hydroxychloroquine intake of >365 g had a significantly lower mean heart rate of 65 ± 7 beats/min as compared with 73 ± 6 beats/min in 24 patients with cumulative hydroxychloroquine intake <365 g. 26 A person taking 400 mg of hydroxychloroquine per day would need to take it for 913 days continuously to reach a cumulative dose of 365 g.…”

“…35 In patients with GFR 20-50 mL/min and 10-20 mL/min the maximum daily dose of hydroxychloroquine can be 75 mg and 50 mg, respectively. 26 Hydroxychloroquine is contraindicated in people with GFR <10 mL/min. 36…”

Hydroxychloroquine: An old drug with new relevance

“…Hydroxychloroquine has been found to decrease the resting heart rate in a cumulative dose-dependent fashion. 47 Further, hydroxychloroquine has been known to increase digoxin levels, and the medications should not be used in combination. 1 Whether the decrease in resting heart rate is associated with harm or benefi t and whether the effect is signifi cant enough to be considered when implementing therapy remain unanswered and deserve further investigation, as does the primary use of hydroxychloroquine for benefi cial lipid and glucose reduction in patients who are otherwise healthy.…”