Sudden unexplained death among subjects with refractory epilepsy

Purpose: To address concerns about possible increases in rates of sudden unexplained death (SUD) after use of new anticonvulsants, more information on the rate of SUD among subjects with refractory epilepsy is needed to provide a comparison. Methods: We conducted a study to estimate the incidence of SUD among subjects younger than 50 years with refractory epilepsy, by using information from the General Practice Research Database (GPRD) in the United Kingdom. For the purposes of this study, subjects receiving two or more anticonvulsant drugs concurrently were considered to have refractory epilepsy. Potential cases of SUD were identified from the computer records, and clinical records for these subjects were reviewed by two specialists in SUD in epilepsy. Results: Fifteen subjects (eight male, seven female) of the 4,150 subjects with refractory epilepsy were considered to have definite/probable or possible SUD. Conclusions: The overall incidence rate of SUD in the population was 2.2 per 1,000 person-years (95% CI, 1.3-3.6). The rate for subjects with highly probable SUD was 1.5 per 1,000 person-years (95% CI, 0.8-2.7).