Cognitive remediation and functional improvement in schizophrenia: Is it a matter of size?

BACKGROUND: Cognitive Remediation represents the best available tool to treat cognitive deficits in schizophrenia and evidence suggests an effect also on global functioning. However, the relationship between cognitive and functional improvement is not yet fully elucidated: do cognitive changes need to be of a definite size and/or encompass a certain number of domains in order to impact on daily functioning? This study aims to explore the role of cognitive improvement, evaluated both quantitatively and qualitatively through the use of Italian equivalent scores, on the daily functioning of patients. As secondary goal, the influence of demographic, clinical and neuropsychological variables on functional outcome was also systematically investigated. METHODS: One hundred subjects with a diagnosis of schizophrenia underwent 36 sessions of Cognitive Remediation and were evaluated at baseline and after the training with the Brief Assessment of Cognition in Schizophrenia and the Quality of Life Scale. RESULTS: A total of 70% of patients improved in at least one cognitive domain and over 50% obtained a normalized score. Among the clinical and neurocognitive factors examined, the only significant predictor of quality of life's improvement was the proportion of cognitive functions that reached an equivalent score of "normal". CONCLUSIONS: This study suggests that improvements in daily functioning depend on the achievement of a cognitive profile as much as possible "normal", harmonious and balanced, supporting the idea that a qualitative leap in cognition is needed in order to gain an advantage in real life activities.