Effect of age and gender on the QTc-interval in healthy individuals and patients with long-QT syndrome

Factors affecting the electrocardiographic QT interval in malaria: A systematic review and meta-analysis of individual patient data

“…Our meta-analysis further confirms established relationships between the QT interval and the demographic factors of age and sex are relevant in malaria. The QT interval does not exhibit a sex difference in childhood [10] until around puberty, when it shortens in males but not females [28], then lengthens gradually in adulthood in males more than females [11]. This difference is thought to result from pubertal changes in sex hormone levels, although the underlying mechanisms are not fully understood [11].…”

“…The square-root-transformed RR interval ( ffi ffi ffi ffi ffi ffi RR p ), sex, body temperature, and malaria type/antimalarial treatment indication were the linear predictors. Age was modelled with separate smooths for females and males because of the known sex-hormone-related QT interval changes around puberty [11]. Weight was omitted because of its collinearity with age in a predominantly paediatric population.…”

“…The QT interval does not exhibit a sex difference in childhood [10] until around puberty, when it shortens in males but not females [28], then lengthens gradually in adulthood in males more than females [11]. This difference is thought to result from pubertal changes in sex hormone levels, although the underlying mechanisms are not fully understood [11]. Postpubertal females have a higher risk of torsade de pointes [63] but a lower risk of sudden cardiac death at all ages [64].…”

“…Malaria is characterised by red blood cell parasitisation, fever, and anaemia [8]. Malaria illness itself may affect the heart and in particular the QT interval [9,10], although these disease effects and their possible interaction with other factors known to affect the QT interval [11] are not well-understood [12]. Because malaria illness and antimalarial drug concentrations change over the course of malaria treatment, it is important to characterise the independent contributions of disease and demographic factors on the QT interval in order to avoid misattributing changes solely to drug effects [12].…”

Implantation of Cardioverter-Defibrillator in Children With Long-QT Syndrome: Assessment of Indications, Efficacy, and Safety Based on 10-Year Experience

“…Достоверного преобладания лиц мужского или женского пола среди больных с ИКД в нашем исследовании не было, тогда как, по данным литературы, ИКД чаще имплантируют женщинам с СУИQT [23]. Вероятно, это различие связано с возрастом пациентов, так как известно, что в возрасте до 15 лет мальчики с данным синдромом (особенно LQT1) имеют более высокий риск ВСС, тогда как после периода полового созревания риск ВСС выше у женщин [24,25]. Возрастной пик имплантаций приходится у детей на возраст от 11 до 15 лет, что согласуется с данными исследования С. Berul [8].…”