Changes in personality traits and social development are found
in young first-degree relatives of patients with schizophrenia.
These may be markers for genetic liability towards the illness, a
new study from the USA suggests.
Although possible environmental and genetic risk factors for
schizophrenia have been identified, no single factor or combination
of factors can predict with certainty who will develop the
disorder.
This study, published in the October issue of the British
Journal of Psychiatry, set out to identify aspects of personality
problems and social development that most strongly discriminate
between high-risk and control individuals.
35 adolescent and young-adult first-degree relatives of people
with schizophrenia or schizoaffective disorder, and a control group
of 55 people, were compared at the start of a longitudinal study in
and around Boston, Massachusetts.
Each participant was given a range of tests to assess
psychological problems, personality traits and measures of social
development.
It was found that high-risk participants aged 17 or over showed
less positive involvement with peers, and more problems with peers,
siblings and the opposite gender.
They also showed more ‘physical anhedonia’, a state in which
they were unable to enjoy things which have a ‘reward value’, and
would normally have given them pleasure.
The authors of the study comment that their results are in line
with several previous studies of people at high genetic risk of
schizophrenia.
The study confirms that high-risk participants have different
personality traits from those of control participants, and also
identifies the specific traits of co-cooperativeness, reward
dependence and self-directiveness as key risk indicators.
There is evidence that physical anhedonia mediates the
relationship between genetic risk of schizophrenia and later social
dysfunction. It will become critical, say the researchers, to
monitor the emergence of physical anhedonia and social dysfunction
among younger high-risk participants who so far have shown no
difference from control participants in these respects.
If social difficulties, in particular, are found to predict the
eventual emergence of full schizophrenia among the high-risk people
in this longitudinal study, they may provide useful targets for
early intervention efforts.
These particular social behaviours may be easier than
personality traits or physical anhedonia to identify and alter.
Children and siblings of people with schizophrenia are about 10
times more likely to develop schizophrenia or a related disorder
than the general population. These high-risk people therefore need
careful monitoring.
Even if they do not develop psychosis, the results of this study
suggest that they are at high risk of social dysfunction and the
expression of abnormal personality traits, and thus of a lowered
quality of life.
Future follow-up studies of this sample of high-risk people will
help to clarify psychological processes in schizophrenia, develop
accurate predictors of psychosis, and identify treatment targets
for early intervention and prevention programmes.
For further information, please contact Liz Fox or Deborah
Hart in the Communications Department.
Telephone: 020 7235 2351 Extensions. 6298 or 6127