Neurological abnormalities in schizophrenic twins.
BACKGROUND
Neurological abnormalities (NAs) are well recognized in schizophrenia, though their genetic and environmental determinants, and pathophysiological significance, are poorly understood.


METHODS
Sixty-three twin pairs, varying in their zygosity and concordance for schizophrenia, and 73 unaffected control twin pairs were examined for total, primary and integrative NAs using the Neurological Evaluation Scale.


RESULTS
NAs were increased in probands with schizophrenia compared to nonschizophrenic co-twins and to healthy control twins but there were no significant differences between patients from the concordant and discordant pairs. NAs in the nonpsychotic co-twins from discordant pairs were increased compared to control twins. There were no significant differences in NAs between the nonschizophrenic co-twins from monozygotic (MZ) and dizygotic (DZ) discordant pairs, but the within pair correlations were greater in the MZ compared to DZ pairs. NAs were modified in all groups by pre-morbid schizotypal traits, and in patients by anti-psychotic medication.


CONCLUSIONS
NAs in schizophrenia are determined in part by genetic risk for the illness but the presence of premorbid schizotypal traits, and anti-psychotic medication confer additional risk for NAs.
Picchioni
Marco M
MM
Division of Psychological Medicine, Institute of Psychiatry, Kings College London, London, United Kingdom. m.picchioni@iop.kcl.ac.uk
Toulopoulou
Timothea
T
Landau
Sabine
S
Davies
Nadia
N
Ribchester
Tracy
T
Murray
Robin M
RM
D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use; D003627:Data Interpretation, Statistical; D004777:Environment; D005260:Female; D006801:Humans; D008297:Male; D009420:Nervous System / Q000503:physiopathology*; D009422:Nervous System Diseases / Q000150:complications / Q000503:physiopathology*; D009460:Neurologic Examination; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000235:genetics / Q000473:pathology; D012018:Reflex / Q000502:physiology; D012306:Risk; D012559:Schizophrenia / Q000150:complications / Q000235:genetics / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D014429:Twins, Dizygotic; D014430:Twins, Monozygotic
D014150:Antipsychotic Agents