This article brought forth some interesting observations. First, a major caveat - this study was done in mice. Mice with a relevant mutation in the Scn1a gene have proven to be a useful model of Dravet, but one must never directly extrapolate any results to humans. Dividing the day into three 8-hour periods, it [...]
(Frasier et al. 2018) It has long been known that SCN1A is expressed in heart cells as well as brain cells, and for several years scientists have hypothesized that the high rate of mortality in patients with Dravet syndrome could be due in part to some dysfunction in the heart caused by SCN1A mutations. The [...]
(Kim et al. 2018) SUDEP is believed to be caused by cardiorespiratory arrest (or the stopping of the heart and breathing). However, it is not clear whether heart rate slows and stops, causing respirations to stop, or vice versa. Because SCN1A is expressed in heart tissue as well as brain tissue, scientists have hypothesized that SUDEP [...]
(Anderson LL et al. 2017). Sodium channel blockers usually make seizures worse in Dravet syndrome, which can be a confusing concept since we associate problems with the sodium ion channel due to SCN1A mutations leading to overexcitation and, hence, seizures. The key to understanding this apparent contradiction is that SCN1A is mainly expressed in inhibitory interneurons. [...]
(Shmuely, 2016). This study reviewed more than 70 previously published articles and meeting extracts on mortality in Dravet syndrome and analyzed 177 cases of death in Dravet syndrome. Sudden unexpected death in epilepsy (SUDEP) was the cause of death in nearly half of those cases, followed by status epilepticus in 32%, drowning/accidental death in 8%, [...]
(Cooper, 2016). E xamining 100 patients with Dravet syndrome (87 of whom had SCN1A mutations) over a follow-up period averaging 17 years, the authors reported that 17 patients died (17%). Ten of those were caused by SUDEP, 4 by status epilepticus, 2 by drowning, and 1 by asphyxia. Taking into account the follow-up time period, [...]
