Case-control study developing Scottish Epilepsy Deaths Study Score to predict epilepsy-related death

Abstract

This study aims to develop a risk prediction model for epilepsy-related death in adults. In this age- and sex-matched case-control study, we compared adults (aged ≥16 years) who had epilepsy-related death between 2009–2016 to living adults with epilepsy in Scotland. Cases were identified from validated administrative national datasets linked to mortality records. ICD-10 cause-of-death coding was used to define epilepsy-related death. Controls were recruited from a research database and epilepsy clinics. Clinical data from medical records were abstracted and used to undertake univariable and multivariable conditional logistic regression to develop a risk prediction model consisting of four variables chosen a priori. A weighted sum of the factors present was taken to create a risk index – the Scottish Epilepsy Deaths Study Score (SEDS Score). Odds ratios (OR) were estimated with 95% confidence intervals (CIs). 224 deceased cases (mean age 48 years, 114 male) and 224 matched living controls were compared. In univariable analysis, predictors of epilepsy-related death were recent epilepsy-related accident and emergency (A&E) attendance (OR 5.1, 95% CI 3.2–8.3), living in deprived areas (OR 2.5, 95% CI 1.6–4.0), developmental epilepsy (OR 3.1, 95% CI 1.7–5.7), raised Charlson Comorbidity Index (CCI) score (OR 2.5, 95% CI 1.2–5.2), alcohol abuse (OR 4.4, 95% CI 2.2–9.2), absent recent neurology review (OR 3.8, 95% CI 2.4–6.1), and generalised epilepsy (OR 1.9, 95% CI 1.2–3.0). SEDS Score model variables were derived from the first four listed above, with CCI ≥2 given 1 point, living in the two most deprived areas given 2 points, having an inherited or congenital aetiology or risk factor for developing epilepsy given 2 points, and recent epilepsy-related A&E attendance given 3 points. Compared to having a SEDS Score of 0, those with a SEDS Score of 1 remained low risk, with OR 1.6 (95% CI 0.5–4.8). Those with a SEDS Score of 2–3 had moderate risk, with OR 2.8 (95% CI 1.3–6.2). Those with a SEDS Score of 4–5 and 6–8 were high risk, with OR 14.4 (95% CI 5.9–35.2) and 24.0 (95% CI 8.1–71.2), respectively. The SEDS Score may be a helpful tool for identifying adults at high risk of epilepsy-related death and requires external validation.

Sudden unexpected death in epilepsy

“…A reprise of this study in a Canadian cohort reported a similar incidence in children [9]. Remarkably, several newer studies in a variety of countries and patient populations reveal similar incidences as those reported in the Swedish and Canadian studies [6,10–19].…”

“…Several risk factors for SUDEP have been identified, including having frequent generalized convulsive seizures (GCS), having nocturnal seizures, being found prone and being male, among others [7]. Importantly, these same themes emerged in most of the studies conducted in other countries and published in the last year or so [6,[10][11][12][13][14][15][16][17][18][19]22]. Many of these risk factors have been combined into a new risk assessment scale, the SUDEP clinical risk score (SUDEP-CARE) [23].…”

Developing and validating a clinical prediction model to predict epilepsy-related hospital admission or death within the next year using administrative healthcare data: a population-based cohort study protocol

“…The primary driver of which variables are selected will be consensus amongst the clinical research team and our Public Advisors (people affected by epilepsy) on which predictors are most important clinically and are readily accessible in the datasets (i.e. missing data patterns will be incorporated into the decision-making) [10]. The focus will not be on the strength of the predictor (e.g.…”

“…(i) consider each binary outcome (A = seizure-related ED or hospital admission, and B = epilepsy-related death) separately, and develop individual prediction models for each using logistic regression [2,10];…”

“…As we previously demonstrated [7], people with epilepsy (PWE) are at substantially increased risk of seizure-related emergency department (ED) or hospital admission [8]. Indeed, seizures are the most common neurological cause of ED or hospital admission in England [8], and such admissions can be predictors of subsequent epilepsy-related death [9, 10]. However, undergoing ED or hospital admission for epilepsy is often clinically unnecessary and typically leads to little benefit for management of the epilepsy because treatment decisions in epilepsy are complex and require specialist expertise, training and guidance [8].…”