European Psychiatry - Volume 33 - March 2016

82 / 812

S78 24th European Congress of Psychiatry / European Psychiatry 33S (2016) S72–S115
Cognitive neuroscience
FC16
A novel protocol to assess dual task
cost as a potential measure of
cognitive reserve
A. Oliveira-Maia ∗, I. Coelho , J.B. Barahona-Corrêa , V. Paixão ,
M. Camacho , R.M. Costa
1 Champalimaud Clinical Centre, Champalimaud Centre for the
Unknown, Neuropsychiatry Unit, Lisbon, Portugal
2 Champalimaud Centre for the Unknown, Champalimaud Research,
Lisbon, Portugal
∗ Corresponding author.
Introduction Methods for measuring cognitive reserve (CR) are
limited and controversial. Dual task cost (DTC) paradigms, assessing
links between gait and cognition, are increasingly regarded as
robust measures of CR.
Objectives Here, we aimed to validate a simplified methodology
for a DTC paradigm in healthy volunteers for application in clinical
settings as a measurement of CR.
Methods We tested if subtracting by 7’s (cognitive task) while
walking (motor task) induced a DTC in a sample of 39 healthy young
adults. For the cognitive task, we recorded the number of correct
and incorrect subtractions, as well as the latency between subtrac-
tions. Gait parameters were recorded on a tri-axial accelerometer
fixed to the left ankle. Both tasks were performed separately (sin-
gle task) and simultaneously (double task) to assess the DTC. A
battery for neuropsychological assessment and questionnaires to
assess quality of life and affective symptoms were also applied, to
measure possible correlations with the DTC.
Results Subtracting 7’s while walking caused significant changes
in gait parameters and in cognitive task performance. A significant
decrease in the autocorrelation of the accelerometer signal dur-
ing the dual task was also found (DTC = 37.92 ± 7.56%; P < 0.0001).
This measure has not been previously used and may be a more
sensitive measure of the dual task induced disturbance of the gait
periodic signal pattern. Correlations between DTC and quality of
life, affective or cognitive measures were not significant.
Conclusion Our study provides an effective, portable and non-
intrusive DTC experimental protocol that can be easily applied in
clinical settings.
Disclosure of interest The authors have not supplied their decla-
ration of competing interest.
FC17
Cortisol, life events and cognition in
non-demented subjects: A
population-based study
S. Ouanes ∗, E. Castelao , A. Von Gunten , M. Preisig , J. Popp
CHUV, Department of Psychiatry, Lausanne, Switzerland
∗ Corresponding author.
Background Older people are particularly exposed to stress-
ful events, known to activate the hypothalamus-pituitary-adrenal
axis. Many studies highlighted the possible deleterious effects of
elevated cortisol on cognition, assuming a likely role of stressful
events. Yet, very fewstudies actually examined these assumed links
between life events, cortisol and cognition.
Objective To examine associations between salivary cortisol,
cognition and life events in a population of non-demented old indi-
viduals.
Methods A cross-sectional analysis was conducted using data
from Colaus/PsyColaus, a longitudinal population-based study
involving 6733 Lausanne residents. Salivary cortisol samples (upon
waking, 30minutes after waking, at 11 am and at 8 pm) were
obtained from 799 non-demented participants aged at least 60.
Life events, activities of daily life along with depressive symptoms
were assessed using a standardized questionnaire. A comprehen-
sive neuropsychological test battery was used to determine the
Clinical Dementia Rating (CDR).
For multiple comparisons, P values were adjusted (P ) according to
Holm-Bonferroni’s method.
Results Cortisol at 11 am and cortisol area under the curve (AUC)
were positively correlated with CDR sum of boxes (CDRSOB) scores
(P = 0.035; Rho = 0.097 and P = 0.024; Rho = 0.110, respectively).
The association between cortisol AUC and CDRSOB remained sig-
nificant after controlling for age, sex, body mass index, education,
smoking and depression ( P = 0.001; = 0.001; R2 change = 0.016).
The number and the total impact of life events were associated
neither with cortisol nor with CDRSOB.
Conclusions Elevated cortisol was associated with poorer cogni-
tive functioning yet independently of life events. This suggests that
the increased cortisol associated with poorer cognition might be
not a mere reflection of stressful events but rather explained by
other factors, yet to be elucidated.
Disclosure of interest The authors have not supplied their decla-
ration of competing interest.
FC18
The EVACO Project: A new battery for
assessing social cognition disorders
and related psychiatric disability in
schizophrenia
P. Roux ∗, M. Urbach , S. Fonteneau , B. Aouizerate ,
F. Berna , L. Brunel , D. Capdevielle , I. Chereau ,
J. Danion , J. Dorey , C. Dubertret , J. Dubreucq ,
C. Faget Gabayet M. Llorca Mallet
D. Misdrahi Rey Richieri
F. Schürhoff Yazbek Passerieux
E. Brunet-Gouet E-SCZ-Grou
1 Fondation FondaMental, Créteil, France
2 Service de psychiatrie d’adulte, Centre Hospitalier de Versailles, UFR
des Sciences de la Santé Simone Veil, Université Versailles
Saint-Quentin-en-Yvelines, Versailles, France
3 Centre Hospitalier Charles-Perrens, 33076 Bordeaux, France
4 Université de Bordeaux, Bordeaux, France
5 Inserm, Neurocentre Magendie, Physiopathologie de la Plasticité
Neuronale, U862, 33000 Bordeaux, France
6 Hôpitaux Universitaires de Strasbourg, Université de Strasbourg,
Inserm U1114, Fédération de Médecine Translationnelle de
Strasbourg, Strasbourg, France
7 Inserm U955, Translational Psychiatry team, Créteil, France
8 Paris Est University, DHU Pe-PSY, Pôle de Psychiatrie des Hôpitaux
Universitaires H.-Mondor, Créteil, France
9 Service Universitaire de Psychiatrie Adulte, Hôpital la Colombière,
CHRU de Montpellier, Université Montpellier 1, Inserm 1061,
Montpellier, France
10 CMP B, CHU, EA 7280 Faculté de Médecine, Université d’Auvergne,
BP 69, 63003 Clermont-Ferrand cedex 1, France
11 Université Claude-Bernard Lyon 1, Centre Hospitalier Le Vinatier
Pole Est, BP 300, 39–95, boulevard Pinel, 69678 Bron cedex, France
12 AP–HP, Department of Psychiatry, Louis-Mourier Hospital, Inserm
U894, Université Paris Diderot, Sorbonne Paris Cité, Faculté de
médecine, Colombes, France
13 Centre Référent de Réhabilitation Psychosociale, Centre Hospitalier
Alpes Isère, Grenoble, France
14 Assistance publique des Hôpitaux de Marseille (AP–HM), pôle
universitaire de psychiatrie, Marseille, France
15 CNRS UMR 5287-INCIA, France