WILLIAM LENNOX[apos]S TWIN STUDY COMPARED WITH RECENT DATA: LESSONS IN CLASSIFICATION AND GENETICS
Abstract number :
1.202
Submission category :
Year :
2003
Submission ID :
2140
Source :
www.aesnet.org
Presentation date :
12/6/2003 12:00:00 AM
Published date :
Dec 1, 2003, 06:00 AM
Authors :
Lata Vadlamudi, Eva Andermann, Cesare T. Lombroso, Steven C. Schachter, Roger L. Milne, John L. Hopper, Frederick Andermann, Samuel F. Berkovic Epilepsy Research Institute, University of Melbourne, Melbourne, Victoria, Australia; Montreal Neurological Ins
William Lennox recognized the value of twin studies in analysing the genetics of epilepsy and collected a series of twins between 1934 and 1958. His files were archived, which allowed us the opportunity to re-evaluate this unique resource. We analysed the data according to modern classifications of epileptic seizures and syndromes. We also compared concordances for epilepsy syndromes with recent Australian twin data.
There were 143 twin pairs reviewed from Lennox[rsquo]s original files. Each twin individual was classified for seizures and syndromes. The twin pairs were divided into 71 monozygous (MZ) and 72 dizygous (DZ) twin pairs for estimation of casewise concordances for epilepsy syndromes.
Seizure analysis demonstrated strong links between the contemporary seizure classifications and Lennox[rsquo]s terminology. In 32 cases diagnosed with absence seizures, the term [ldquo]petit mal[rdquo] was used by Lennox in 29 cases. Lennox used the term [ldquo]psychomotor seizures[rdquo] in 47 cases, of which we regarded 45 as either simple or complex partial seizures. There was striking similarity between the two data sets for casewise concordances for all generalized epilepsies (Lennox:Australian, MZ 0.80:0.82; DZ 0.27:0.26). In the partial epilepsies higher MZ concordance was seen in the Australian twin data (MZ 0.09:0.36; DZ 0.06:0.05). In febrile seizures, both data sets demonstrated high MZ concordances (MZ 1.0:0.58; DZ 0.67:0.14).
This is the first study to demonstrate historical seizure terminology, as used by Lennox, corresponds closely to contemporary terms showing that his data remains valuable. With the exception of partial epilepsies, where the Lennox data did not show an inherited contribution (perhaps due to issues of power or errors in retrospective classification), the similarity with contemporary Australian twin data was remarkable. In particular, the major genetic contribution in generalized epilepsies and febrile seizures were highlighted, despite two populations differing in era and continent. This now allows the potential to combine these large data sets, for more detailed analyses of sub-syndromes.
[Supported by: Nil]