Most cited article - PubMed ID 35231876
The relationships between cognitive reserve, cognitive functioning and quality of life in first-episode schizophrenia spectrum disorders
Acute and transient psychotic disorder (ATPD) is characterized by acute onset of psychotic symptoms and early recovery. Contrastingly, schizophrenia (SZ) is a chronic mental disorder characterized by impaired functioning including a deficit in cognition. In SZ, the cognitive deficit is among the core symptoms, but in ATPDs, the existing evidence brings mixed results. Our primary aim was to compare three core cognitive domains (executive functioning/abstraction, speed of processing and working memory) of patients diagnosed with ATPD and SZ over a 12-month period. Moreover, we explored how these diagnostic subgroups differed in their clinical characteristics. We recruited 39 patients with a diagnosis of SZ and 31 with ATPD with schizophrenic symptoms. All patients completed clinical and neuropsychological assessments. At baseline, we used a one-way ANCOVA model with a group as the between-subjects factor. Mixed-model repeated-measures ANOVAs with time as the within-subjects factor and group as the between-subjects factor were run to test the overtime differences. At baseline, we did not find any differences in cognition - with sex, education and age as covariates - between ATPDs and SZ. After one year, all patients showed an improvement in all three domains, however, there were no significant overtime changes between ATPDs and SZ. Regarding clinical profiles, ATPDs demonstrated less severe psychopathology and better functioning compared to SZ both at baseline and after 12 months. The medication dosage differed at retest, but not at baseline between the groups. Our findings suggest clinical differences and a similar trajectory of cognitive performance between these diagnostic subgroups.
- Keywords
- Acute and transient psychotic disorder, Brief psychotic disorder, Cognition, First-episode, Schizophrenia,
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- Journal Article MeSH
Deficits in memory performance have been linked to a wide range of neurological and neuropsychiatric conditions. While many studies have assessed the memory impacts of individual conditions, this study considers a broader perspective by evaluating how memory recall is differentially associated with nine common neuropsychiatric conditions using data drawn from 55 international studies, aggregating 15,883 unique participants aged 15-90. The effects of dementia, mild cognitive impairment, Parkinson's disease, traumatic brain injury, stroke, depression, attention-deficit/hyperactivity disorder (ADHD), schizophrenia, and bipolar disorder on immediate, short-, and long-delay verbal learning and memory (VLM) scores were estimated relative to matched healthy individuals. Random forest models identified age, years of education, and site as important VLM covariates. A Bayesian harmonization approach was used to isolate and remove site effects. Regression estimated the adjusted association of each clinical group with VLM scores. Memory deficits were strongly associated with dementia and schizophrenia (p < 0.001), while neither depression nor ADHD showed consistent associations with VLM scores (p > 0.05). Differences associated with clinical conditions were larger for longer delayed recall duration items. By comparing VLM across clinical conditions, this study provides a foundation for enhanced diagnostic precision and offers new insights into disease management of comorbid disorders.
- Keywords
- Parkinson’s disease, attention-deficit/hyperactivity disorder, bipolar disorder, dementia, depression, memory, schizophrenia, stroke, traumatic brain injury, verbal learning,
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- Journal Article MeSH
Schizophrenia has a profound influence on the real-life functioning of patients. There are several factors inherent to the disease course affecting the level of psychosocial functioning. Our study focused on the impact of cognitive deficit and severity of negative symptoms (i.e., the experiential domain (avolition, asociality, and anhedonia) and the expressive domain (blunted affect and alogia)) to explore psychosocial functioning in schizophrenia. Schizophrenia patients (n = 211) were tested for the presence of cognitive impairment using the NIMH-MATRICS: Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Cattery (MCCB; MATRICS Consensus Cognitive Battery) and the extent of negative symptoms using the PANSS (PANSS; Positive and Negative Syndrome Scale-selected items). The level of psychosocial functioning was measured with the Personal and Social Performance Scale (PSP). The path analysis using three regression models was used to analyse variables influencing psychosocial functioning (PSP). One of these models analyzed influence of cognitive functioning (MCCB) and negative schizophrenia symptoms (PANSS selected items reflecting expressive and experiential deficits) as predictors and NART/CRT and disease length as confounders. R2 was 0.54. The direct effect of the MCCB (β = 0.09) on the PSP was suppressed by the strong effect of the negative symptoms (β = -0.64). The presence of cognitive deficits and negative symptoms in our sample of schizophrenia patients significantly influences the level of their psychosocial functioning, a key factor in remission and recovery.
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INTRODUCTION: Individuals with schizophrenia spectrum disorders (SSDs) record elevated rates of smoking, which is often attributed to their effort to self-medicate cognitive and attentional symptoms of their illness. Empirical evidence for this hypothesis is conflicting, however. In this study, we aimed to test predictions derived from the cognitive self-medication hypothesis. We predicted that cigarette smoking status and extent would predict the attentional performance of participants with SSDs. Simultaneously, we wished to address methodological gaps in previous research. We measured distinct attentional components and made adjustments for the effects of other, attention-modulation variables. METHODS: Sixty-one smokers (82.0% males, 26.73 ± 6.05 years) and 61 non-smokers (50.8% males, 27.10 ± 7.90 years) with recent-onset SSDs completed an X-type Continuous Performance Test, which was used to derive impulsivity and inattention component scores. Relationships between the two component scores and cigarette smoking status and extent were assessed using hierarchical regression. Effects of estimated premorbid intellectual functioning and antipsychotic medication dosage were held constant. RESULTS: Smokers had significantly higher inattention component scores than non-smokers when covariates were controlled (p = 0.026). Impulsivity remained unaffected by smoking status (p = 0.971). Cigarette smoking extent, i.e., the number of cigarettes smoked per day, was not associated with either inattention (p = 0.414) or impulsivity (p = 0.079). CONCLUSION: Models of smoking-related attentional changes can benefit from the inclusion of sample-specific component scores and attention-modulating covariates. Under these conditions, smokers with SSDs can show a partial attentional benefit. However, the limited scope of this benefit suggests that the cognitive self-medication hypothesis requires further testing or reconsidering.
- Keywords
- CPT, attention, first-episode, nicotine, psychotic disorder, schizophrenia, self-medication, smoking,
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- Journal Article MeSH