Investigators from the Institute of Neurology, Queen Square, London, UK, report results of longitudinal cohort studies of prognosis in epilepsy in adults and children and focus particularly on the National General Practice Study of Epilepsy (NGPSE) in 1195 patients initiated in 1983. Other longitudinal studies include the Mayo Clinic Record Linkage Study, the Tonbridge Study and the Study from Turku, confined to children and initiated in the 1970s. The findings are summarized as follows: 1) Epilepsy prognosis is frequently good, 65-85% cases entering long-term remission; 2) prognosis is better in newly diagnosed cases than in patients with chronic epilepsy; 3) early response to treatment is usually an indication of a good long-term prognosis; 4) the longer the remission, the less likely a subsequent recurrence; 5) the longer seizures recur, the poorer the long-term outlook; 6) delaying treatment, even for many years, does not worsen long-term prognosis; 7) continuous and burst patterns are more common than intermittent seizure patterns; 8) mortality may occur at any time in the course of epilepsy but is highest in the early years after diagnosis and is largely due to the underlying cause; 9) febrile seizure prognosis is generally good with ∼6-7% developing late epilepsy (rate of epilepsy developing is higher in those with FS occurring before age 1 year or after age 3 years, and with complex FS); and 10) clinical factors associated with a poor prognosis include a neurodeficit, poor response to initial therapy, and some epilepsy syndromes. 
COMMENT. Ethics committee approval had been obtained at the beginning of the study, which did not require patient consent for collection of anonymized prognostic data. In 2007 a government appointed committee ruled that, with some exceptions, the patient's consent was required for collection of personal data from the general practitioner. The reduction in available data that followed has resulted in the premature termination of the study. The authors comment that this ill-advised decision by government appointed committees has harmed large-scale epidemiological studies in Britain, and specifically resulted in loss of 30-year follow-up of a large cohort of patients with epilepsy and reasons for a persistently high mortality.