[Show abstract][Hide abstract] ABSTRACT: The thickness of the cortical mantle is a sensitive measure for identifying alterations in cortical structure. We aimed to explore whether first episode schizophrenia patients already show a significant cortical thinning and whether cortical thickness anomalies may significantly influence clinical and cognitive features.
We investigated regional changes in cortical thickness in a large and heterogeneous sample of schizophrenia spectrum patients (n=142) at their first break of the illness and healthy controls (n=83). Magnetic resonance imaging brain scans (1.5 T) were obtained and images were analyzed by using brains2. The contribution of sociodemographic, cognitive and clinical characterictics was investigated.
Patients showed a significant total cortical thinning (F=17.55, d=-0.62, p<0.001) and there was a diffuse pattern of reduced thickness (encompassing frontal, temporal and parietal cortices) (all p's<0.001, d's>0.53). No significant group×gender interactions were observed (all p's>0.15). There were no significant associations between the clinical and pre-morbid variables and cortical thickness measurements (all r's<0.12). A weak significant negative correlation between attention and total (r=-0.24, p=0.021) and parietal cortical thickness (r=-0.27, p=0.009) was found in patients (thicker cortex was associated with lower attention). Our data revealed a similar pattern of cortical thickness changes related to age in patients and controls.
Cortical thinning is independent of gender, age, age of onset and duration of the illness and does not seem to significantly influence clinical and functional symptomatology. These findings support a primary neurodevelopment disorder affecting the normal cerebral cortex development in schizophrenia.
Psychological Medicine 10/2010; 41(7):1449-60. · 5.59 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The impact of different levels of depression severity on quality of life (QoL) is not well studied, particularly regarding ICD-10 criteria. The ICD classification of depressive episodes in three levels of severity is also controversial and the less severe category, mild, has been considered as unnecessary and not clearly distinguishable from non-clinical states. The present work aimed to test the relationship between depression severity according to ICD-10 criteria and several dimensions of functioning as assessed by Medical Outcome Study (MOS) 36-item Short Form general health survey (SF-36) at the population level.
A sample of 551 participants from the second phase of the Outcome of Depression International Network (ODIN) study (228 controls without depression and 313 persons fulfilling ICD criteria for depressive episode) was selected for a further assessment of several variables, including QoL related to physical and mental health as measured with the SF-36.
Statistically significant differences between controls and the depression group were found in both physical and mental markers of health, regardless of the level of depression severity; however, there were very few differences in QoL between levels of depression as defined by ICD-10. Regardless of the presence of depression, disability, widowed status, being a woman and older age were associated with worse QoL in a structural equation analysis with covariates. Likewise, there were no differences according to the type of depression (single-episode versus recurrent).
These results cast doubt on the adequacy of the current ICD classification of depression in three levels of severity.
Psychological Medicine 02/2010; 40(12):2069-77. · 5.59 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: It has become widely accepted that cognitive deficits in schizophrenia are related to functional outcome. However, it remains to be seen whether these associations are relevant for predicting which cases will have a global functional recovery. In this study, we attempt to determine whether global functional recovery (integrating social and occupational outcomes) after first-episode schizophrenia (FES) can be predicted by cognitive variables.
A total of 131 FES patients with functional deficits (n=97) and functional recovery (n=34) as determined at 1-year follow-up were examined. Neuropsychological, sociodemographic, pre-morbid and clinical data at baseline were analysed using independent groups comparisons and a logistic regression method.
Sustained attention and negative symptoms emerged as significant predictors of good global functional outcome. Although the model revealed a high accuracy (91%) in the classification of patients with functional deficits, it was unacceptably low (26%) in the classification of patients with global functional recovery.
The limitations found in the prediction of a favourable global functional outcome may well be an indication for a need to address the role of other factors not commonly included in longitudinal studies of long-term outcomes in schizophrenia.
Psychological Medicine 09/2009; 40(6):935-44. · 5.59 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Predicting cognitive deficits in early psychosis may well be crucial to identify those individuals most in need of receiving intensive intervention. As yet, however, the identification of potential pretreatment predictors for cognitive performance has been hampered by inconsistent findings across studies. We aimed to examine the associations of functional and clinical pretreatment variables with cognitive functioning after a first psychotic episode.
One hundred and thirty-one patients experiencing first-episode psychosis were assessed for psychopathology, pre-morbid functioning, duration of illness, age of onset, and family history of psychosis and neurocognitive functioning. Multiple regression analyses were conducted for six basic cognitive dimensions known to be affected in this population: verbal learning, verbal memory, verbal comprehensive abilities, executive functioning, motor dexterity and sustained attention.
Pre-morbid functioning was the main predictor for five out of the six basic cognitive domains. Pre-morbid social adjustment difficulties were associated with worse performance in executive functioning, motor dexterity and sustained attention. Academic functioning was associated with verbal comprehension, and verbal learning and memory. Gender, age of onset, duration of untreated psychosis, and family history of psychosis had no or limited value as predictors of neurocognitive outcome.
Poor pre-morbid functioning was related to a worse performance in the six basic cognitive dimensions evaluated; however, this accounted for only a small amount of the explained variance. Cognitive impairment is a prominent feature in patients with early psychosis regardless of favorable prognostic features such as short duration of illness, female gender, later age of onset, and non-family history of psychosis.
Psychological Medicine 06/2008; 38(5):737-46. · 5.59 Impact Factor