SUDEP in the Netherlands

We would like to respond to the letter sent by Dr. Bell and Dr. Sander on 6th March. Firstly, the establishment of survivor status for all attendees of the tertiary referral centre for epilepsy is questioned. Through the electronical patient record system, which is continually updated, we obtained an exact number of deaths in our patient population. Consequently, there is no reason to believe an underestimation of death rates has occurred. The number of patient years was derived from the number of patients attending the epilepsy centre during the period under study. Again, the electronical patient record system provided reliable numbers of attending patients. A mean number of 4400 people with epilepsy were treated per year. The majority of this population is receiving chronic treatment for their epilepsies. Another part of the population stays under the attention of the epilepsy centre for a shorter period, but there is a steady turnover of these patients which is illustrated in the mean number of attending patients. The study period comprised 5.3 years resulting in 23,230 patient years. With 29 definite and probable SUDEP cases, the SUDEP rate of 1.24 per 1000 patient years was calculated. If we would have included only definite SUDEP cases, the SUDEP rate would have been even lower, that is 0.21 per 1000 patient years, but we believe this would be an actual underestimation of SUDEP. If we would have obtained exact patient years of follow up, perhaps we would have obtained a slightly lower number of