

S106
24th European Congress of Psychiatry / European Psychiatry 33S (2016) S72–S115
contribution of these mechanisms to the ERP in patients with
schizophrenia (SCZ).
Materials and methods
One hundred and fifteen chronic stabi-
lized SCZ and 62 healthy controls (HC) recruited to the study of the
Italian Network for Research on Psychoses were included. Scalp
potentials were recorded during a standard auditory oddball task.
Stimulus-locked segments were extracted for all standard trials
and correctly hit target trials. Trials contaminated by other artifacts
were rejected. For each subject and stimulus type the event-related
spectral perturbation (ERSP) and the inter-trial-coherence (ITC)
were computed to assess event-related power increase and inter-
trial phase-locking. The two groups were compared using Student’s
t
-test followed by Bonferroni correction for multiple comparisons.
Results
SCZ presented a reduced amplitude of bothN100 and P3b.
For both standard and target stimuli, at Cz and Pz, ERSPwas reduced
in SCZ in the delta-theta band (from 0 up to 400ms). The ITC index,
at the same channels, was reduced in SCZ in the delta band for
standard stimuli (from 0 to 300ms), and in both delta and theta
bands for target stimuli (from 300 to 400ms).
Conclusions
Our results indicate that alterations of both mecha-
nisms are involved in N100 and P3b amplitude reduction observed
in SCZ. Inter-trial phase-locking abnormalities for N100 were
limited to the delta band, while for P3b involved delta and theta
frequencies.
Disclosure of interest
The authors have not supplied their decla-
ration of competing interest.
http://dx.doi.org/10.1016/j.eurpsy.2016.01.085FC82
Methylenetetrahydrofolate reductase
(
MTHFR
) gene polymorphisms and
antipsychotic-induced metabolic
disturbances in first-episode
schizophrenia patients
B. Misiak
1 ,∗
, Ł. Łaczma ´nski
2, K. Słoka
2, E. Szmida
3, R. ´Sl˛ezak
3,
P. Piotrowski
1, A. Kiejna
1, D. Frydecka
11
Wroclaw Medical University, Department of Psychiatry, Wroclaw,
Poland
2
Wroclaw Medical University, Department of Endocrinology and
Diabetology, Wroclaw, Poland
3
Wroclaw Medical University, Department of Genetics, Wroclaw,
Poland
∗
Corresponding author.
Introduction
There is a scarcity of prospective studies addressing
the influence of the
methylenetetrahydrofolate reductase
(
MTHFR
)
gene polymorphisms on antipsychotic-induced metabolic changes
in first-episode schizophrenia (FES) patients.
Objectives
We aimed at investigating metabolic side effects
of second-generation antipsychotics (SGAs) with respect to the
MTHFR
gene polymorphisms in FES patients.
Methods
Polymorphisms in the
MTHFR
gene (C677T and A1298C)
were investigatedwith respect to changes in bodymass index (BMI)
and waist circumference (WC) together with serum levels of glu-
cose, lipids, homocysteine, vitamin B12 and folate after 12 weeks
of treatment with SGAs in 135 FES patients.
Results
The 677TT genotype was associated with significantly
higher BMI, WC and serum levels of triglycerides, as well as signif-
icantly lower folate levels at baseline. Additionally, the 677T allele
was associatedwith significantly lower folate levels at baseline. The
677CC homozygotes had significantly higher increase in BMI and
serum levels of triglycerides. The 677TT genotype predicted sig-
nificantly higher increase in homocysteine levels and significantly
higher decrease in folate levels. These associations were also signif-
icant in the allelic analysis. Only the patients with the 677T allele
had significantly lower folate levels and significantly higher homo-
cysteine levels at the follow-up. The 677T allele was also related to
significantly lower increase in WC. The 1298CC homozygotes had
significantly higher weight gain in the course of treatment with
SGAs.
Conclusions
The
MTHFR
gene polymorphisms might predict
antipsychotic-induced weight gain in FES patients. In addition, the
MTHFR
C677T polymorphismmight be also predictive with respect
to other metabolic adversities of SGAs.
Disclosure of interest
The authors have not supplied their decla-
ration of competing interest.
http://dx.doi.org/10.1016/j.eurpsy.2016.01.086FC83
Clinical symptomatology and theory
of mind in schizophrenia: Which
relationship?
J. Mrizak
∗
, R. Trabelsi , A. Arous , A. Aissa , H. Ben Ammar ,
Z. El Hechmi
Razi Hospital, Psychiatry F, Mannouba, Tunisia
∗
Corresponding author.
Introduction
Theory of mind (ToM) has repeatedly been shown to
be compromised inmany patients with schizophrenia (SCZ). It now
seems to be quitewell-established that patientswithprofoundneg-
ative or disorganized symptoms perform poorly on ToM tasks. By
contrast, findings in patients with predominant positive symptoms
are much more ambiguous.
Objectives
To investigate the relationship between ToM deficits
and different symptoms dimensions in SCZ.
Methods
Fifty-eight outpatients with stable SCZ completed the
intention-inferencing task (IIT), in which the ability to infer a char-
acter’s intentions from 28 short comic strip stories is assessed.
Symptomatology evaluation comprised the Positive and Nega-
tive Syndrome Scale (PANSS), the Calgary Depression Scale for
Schizophrenia (CDSS) and the Clinical Global Impressions Scale
Improvement and severity (CGI).
Results
The number of correct answers in the IIT negatively cor-
related with both the positive (
P
= 0.015) and negative (
P
< 0.0001)
scales of the PANSS. ToM deficits were correlated with the
conceptual disorganization, hallucinations and the suspicious-
ness/persecution items.
The patients who had more false answers in the IIT also had signifi-
cantly higher scores at the positive (
P
= 0.005), negative (
P
< 0.0001)
and general (
P
< 0.0001) scales of the PANSS. Worse IIT performance
correlated with a higher severity index in the CGI. No correlations
were found between IIT scores and CDSS scores.
Conclusions
Our results confirm the relationship between ToM
deficits and negative symtomps and suggest that ToM may also be
correlated to specific positive symptoms.
Disclosure of interest
The authors have not supplied their decla-
ration of competing interest.
http://dx.doi.org/10.1016/j.eurpsy.2016.01.087FC84
Effectiveness of long-acting
injectables and clozapine in a
real-world setting during the
early-stages of psychotic illness
E.G. Ostinelli
∗
, E. Guanella , S. Cavallotti , C. Casetta ,
A. D’Agostino
San Paolo Hospital, Department of Health Sciences, Milan, Italy
∗
Corresponding author.
Introduction
Intervention in the early-stages of psychosis may
be able to shape the clinical course; critical period (CP) is best
represented by the first 5 years from first admission (FA).
Objectives
To investigate the effectiveness of pharmacological
intervention within and beyond the CP.