Prédicteurs cognitifs des différentes dimensions du fonctionnement dans la communauté dans la schizophrénie : revue de la littérature et perspectives

Predictors of community functioning in schizophrenia and substance use disorder patients

Community functioning is a broad term that encompasses various 'real world' measures of disability among schizophrenia patients. It includes outcomes such as independent living, social competence and behavioural problems-all of which are priorities for treatment among schizophrenia patients, mental health care providers, and family members. An important goal for rehabilitation programs is to identify predictors of community functioning which, in turn, could be used as targets for intervention. The present case-control study examined socio-demographic and substance use disorder (SUD) variables as well as psychiatric, extrapyramidal, and cognitive symptoms as predictors of community functioning in schizophrenia patients with (DD patients; n=31) and without comorbid SUDs (SCZ patients; n=31), and non-psychosis substance abusers (SUD patients; n=39). Psychiatric and extrapyramidal symptoms were evaluated with the Positive and Negative Syndrome Scale, the Calgary Depression Scale for Schizophrenia and the Extrapyramidal Symptoms Rating Scale. Cognition was evaluated using the Cambridge Neuropsychological Test Automated Battery (speed of processing, explicit and working memory). In SCZ patients, community functioning was predicted by explicit memory performance. In DD patients, community functioning was predicted by substance abuse, depression and speed of processing. In SUD patients, community functioning was predicted by substance abuse, positive symptoms and education. Our results suggest that cognition should be among the top treatment priorities in SCZ patients, whereas the key treatment targets in DD patients should be substance abuse and depression. Future studies will need to replicate the current findings, using prospective research designs.

Improvement of cognitive flexibility and cingulate blood flow correlates after atypical antipsychotic treatment in drug-naive patients with first-episode schizophrenia

The aim of this study was to examine the changes in cognitive flexibility and associated cerebral blood flow in the anterior cingulate lobe of drug-naive patients with first-episode schizophrenia who were treated with atypical antipsychotics for 6 weeks. Single photon emission computed tomography (SPECT) images were obtained from 8 healthy subjects both at rest and while performing the flexibility subtest of the TAP (Test for Attentional Performance). SPECT images were obtained in parallel from 8 first-episode drug-naive schizophrenic patients while they were performing the same task both before and after 6 weeks of neuroleptic treatment. In the control group, an increase in the perfusion indices of the dorsal section of the anterior cingulate gyrus was observed in the activation condition. Task performance was altered and the level of perfusion of the brain region related to the task execution was significantly decreased in the patients at baseline. After treatment, there was a significant improvement in both task performance and the level of perfusion of the dorsal section of the anterior cingulate. We conclude that treatment with second-generation neuroleptics improves cognitive flexibility, and there was a relationship between such improvements and normalization of perfusion indices of the involved brain areas.