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

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.