Evolution over time of SUDEP incidence: A nationwide population‐based cohort study

Abstract

Prompted by a recent report on declining incidence of sudden unexpected death in epilepsy (SUDEP) following implantation of a vagus nerve stimulator (VNS), we analyzed SUDEP risk over 6 years in a population-based cohort of 60 952 epilepsy patients in Sweden. All deaths from July 1, 2006 through December 31, 2011, were identified. Those with epilepsy mentioned on the death certificate were adjudicated for SUDEP using medical records and autopsy reports. In all, 292 SUDEP cases were identified. Comparing the first years (2006-2007) with the subsequent 4 years (2008-2011), the crude and standardized (to the US 2000 population) incidence of SUDEP (whether or not possible SUDEP was included) was significantly lower during the second time period; Incidence rate ratios based on standardized rates was estimated at 0.76 (95% confidence interval [CI] 0.60-0.97, P = .027) for SUDEP. The incidence of SUDEP decreased by 7% per year during the 6-year follow-up. Our data thus suggest that, for unknown reasons, incidence of SUDEP decreases with duration of follow-up. This has implications for patient counseling as well as for the design of studies attempting to assess the effectiveness of an intervention against SUDEP, which clearly needs to include a control group.

Health Technology Assessment Report on Vagus Nerve Stimulation in Drug-Resistant Epilepsy

“…However, the audit of 466 VNS cases enrolled at a single center showed that patients with VNS carried a similar risk for SUDEP as other drug refractory patients [ 87 ]. Tomson and Ryvlin suggested that the risk of SUDEP significantly decreases during long-term follow-up in VNS therapy [ 88 , 89 ].…”

Sudden unexpected death in epilepsy: The neuro-cardio-respiratory connection

“…Some data suggest that it might reduce the risk of SUDEP [121,122], but not consistently [123]. Furthermore, studies reporting a decline of SUDEP during follow-up lack a control group [122], thus making it impossible to ascribe this effect to VNS treatment or simply to the natural course of SUDEP risk, which other studies have shown to be decreasing overtime with duration of follow-up [124].…”

How can transition to adult care be best orchestrated for adolescents with epilepsy?

“…43. In addition, a large study from Sweden of 57,775 people with epilepsy found the incidence of SUDEP (again in prevalent cases) to be similar across the ages. 47 From the perspective of transition, it would seem prudent to consider SUDEP as an important topic to emphasize as the youth takes responsibility for factors in their control to concentrate on the importance of good seizure control.…”