Differences in saccadic eye movements in subjects at high and low risk for panic disorder.
BACKGROUND
Panic disorder (PD) has a strong genetic component showing high heritability rates and familial aggregation. Moreover, there is evidence for associations between parental PD and patterns of psychopathology. So far, little is known about possible endophenotypes representing premorbid vulnerability markers in high-risk subjects for PD. In the present study, we investigated saccadic eye movement (SEM) as an index of CNS inhibitory function in subjects at high risk for PD.


METHODS
132 healthy children at high and low familial risk for PD were included in the study. Basal SEM parameters were obtained using an electro-oculography (EOG) based system measuring peak saccadic eye velocity (pSEV), latency and accuracy. Moreover, with regard to self rating scales, state-trait-anxiety (STAI-C), childhood behavioral inhibition (CSRI), and anxiety sensitivity (CASI) were assessed.


RESULTS
There was a significant overall difference for basal SEM parameters across groups as revealed by MANCOVA (F7,118=2.184, p=.040). A significant influence was found for the covariate age, while gender and puberty status had no influence on SEM. High-risk (HR) subjects showed significantly lower pSEV. Moreover, levels of state and trait anxiety were higher in HR children (F1=5.429, p=.021).


CONCLUSIONS
In our sample, measurement of pSEV allowed discrimination between children at high and low risk for PD. Since these results argue for possible alterations of saccadic function in high risk subjects, differences in underlying neurobiological mechanisms might be discussed as a possible endophenotype of PD.
Mood and Anxiety Disorders Research Unit, Department of Psychiatry, University of Munster, Albert- Schweitzer-Campus 1, 48149 Muenster, Germany. Zwanzger@ukmuenster.de
Peter
P
Zwanzger
Jacques
J
Bradwejn
Julia
J
Diemer
Roger W
RW
Marshall
Diana
D
Koszycki
D000293:Adolescent; D001007:Anxiety / Q000175:diagnosis*; D016022:Case-Control Studies; D002648:Child; D004585:Electrooculography / Q000379:methods; D005192:Family Health; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D016584:Panic Disorder / Q000235:genetics*; D010290:Parents; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D012438:Saccades