The risk of drowning in patients with epilepsy is quantified by a meta-analysis of published reports, in a study at the Institute of Neurology, Queen Square, London UK. The number of deaths from drowning and the number of person-years at risk were estimated in 51 cohorts of people with epilepsy. Standardized mortality ratios (SMRs) (observed deaths divided by the expected deaths) were calculated for each cohort and for the total population. Compared with 4.7 expected deaths, 88 drowning deaths were reported in people with epilepsy, giving an SMR of 18.7 (95% CI 15-23). The 51 cohorts combined had 206,596 patient-years of follow-up. In people with epilepsy and learning disability, the SMR was 25.7, and in those in institutional care, 96.9. In those with temporal lobectomy for epilepsy, the SMR was 41.1. Using National Registries for estimation of drowning deaths in people with epilepsy in England and Wales (1999-2000), the SMR was 15.3. [1]

COMMENT. Compared to the general population, people with epilepsy have a 15- to 19- fold increase in risk of drowning, according to this meta-analysis of published articles. The actual number of drownings in children is small, only 4 of the 15 articles involving predominantly children including deaths due to drowning. Inadequate supervision was a frequent factor. One previous study suggested that the relative risk of drowning in the bath is 96 for children with epilepsy compared to those without, and for drowning in a swimming pool is 23 [2]. One in 20 deaths from drowning was due to seizures. [3]