Trends in epilepsy mortality of three incidence cohorts across 2006-2023 in Sweden: a matched register-based study.

BACKGROUND

Idiopathic epilepsy alone accounts for a large health burden as shown in the Global Burden of Diseases Study. In countries with ageing populations, secondary epilepsies are now even more common. Altered clinical practice and reduced use of older enzyme-inducing drugs may be beneficial, but understanding of trends in the prognosis of all epilepsy is needed. Our objective was to determine and study trends in mortality in persons with epilepsy in Sweden through 2006-2023.

METHODS

We performed a matched cohort study by cross-referencing National Patient, Drug, and Cause of Death Registers. We included all persons with a diagnosis of epilepsy and antiseizure medication (ASM) after 2006 (n = 61,375) and three age-/sex-matched comparators/case. Mortality was assessed for three incidence cohorts; 2006-2010, 2011-2015, and 2016-2020, totally and in four subgroups: age >50, vascular disease, generalized epilepsy, and age <20. Risk of death was assessed by Cox regression.

FINDINGS

Carbamazepine and valproic acid were common first ASMs in 2006-2010, but replaced by levetiracetam by 2016-2020. Valproate became less common in generalized epilepsy. The adjusted hazard ratio [HR] for death was 1.99 (95% confidence interval [CI]:1.90-2.08) in 2006-2010 and 1.90 (95% CI: 1.82-1.99) in 2016-2020. The adjusted HR for death was 1.59 (95% CI: 1.50-1.68) for persons with cardiovascular disease versus comparators during 2016-2020. A sensitivity analysis showed that the excces risk of cardiovascular death had decreased between our cohorts. Young persons with epilepsy had a 30-50 fold increased HR of death. Dementia and vascular disease were important risk factors for death in persons with epilepsy.

INTERPRETATION

Mortality in epilepsy has remained largely unchanged relative to age- and sex matched comparators. The increased use of non-inducing ASMs may have reduced vascular risk slightly. Efforts should be targeted to specific patient groups, particularly regarding epilepsy management in the young and vascular and neurodegenerative comorbidities in older persons with epilepsy.

FUNDING

Swedish Research Council, Swedish State through the ALF agreement, Knut and Ragnvi Jacobsson foundation.