Abstract
Background
The EEG is a commonly requested test on patients attending psychiatric services, predominantly to investigate for a possible organic brain syndrome causing behavioural changes.
Aims
To assess referrals for EEG from psychiatric services in comparison with those from other sources. We determine which clinical factors were associated with an abnormal EEG in patients referred from psychiatric sources.
Methods
A retrospective review of EEG requests in a 1βyear period was performed. Analysis of referral reasons for psychiatric patients was undertaken, and outcome of patients referred from psychiatric services postβEEG was reviewed.
Results
One thousand four hundred and seventy EEGs were reviewed, of which 91 (6.2%) were referred from psychiatry. Neurology service referrals had detection rates of abnormal EEGs of 27%, with psychiatric referrals having the lowest abnormality detection rate of 17.6% (pβ<β0.1). In psychiatricβreferred patients the only significant predictors found of an abnormal EEG were a known history of epilepsy (pβ<β0.001), being on clozapine (pβ<β0.05), and a possible convulsive seizure (RRβ=β6.51). Followβup data of 53 patients did not reveal a significant clinical impact of EEG results on patient management.
Conclusions
Many patients are referred for EEG from psychiatric sources despite a relatively low index of suspicion of an organic brain disorders, based on reasons for referral documented, with an unsurprising low clinical yield. Copyright Β© 2006 John Wiley & Sons, Ltd.