Static and dynamic cognitive deficits in childhood preceding adult schizophrenia: a 30-year study.
ABSTRACT Premorbid cognitive deficits in schizophrenia are well documented and have been interpreted as supporting a neurodevelopmental etiological model. The authors investigated the following three unresolved questions about premorbid cognitive deficits: What is their developmental course? Do all premorbid cognitive deficits follow the same course? Are premorbid cognitive deficits specific to schizophrenia or shared by other psychiatric disorders?
Participants were members of a representative cohort of 1,037 males and females born between 1972 and 1973 in Dunedin, New Zealand. Cohort members underwent follow-up evaluations at specific intervals from age 3 to 32 years, with a 96% retention rate. Cognitive development was analyzed and compared in children who later developed schizophrenia or recurrent depression as well as in healthy comparison subjects.
Children who developed adult schizophrenia exhibited developmental deficits (i.e., static cognitive impairments that emerge early and remain stable) on tests indexing verbal and visual knowledge acquisition, reasoning, and conceptualization. In addition, these children exhibited developmental lags (i.e., growth that is slower relative to healthy comparison subjects) on tests indexing processing speed, attention, visual-spatial problem solving ability, and working memory. These two premorbid cognitive patterns were not observed in children who later developed recurrent depression.
These findings suggest that the origins of schizophrenia include two interrelated developmental processes evident from childhood to early adolescence (ages 7-13 years). Children who will grow up to develop adult schizophrenia enter primary school struggling with verbal reasoning and lag further behind their peers in working memory, attention, and processing speed as they get older.
- SourceAvailable from: Rodrigo A Cunha[Show abstract] [Hide abstract]
ABSTRACT: The management of schizophrenia endophenotypes, namely positive, negative, and cognitive symptoms is still an open goal, justifying the search of novel therapeutic avenues. We now review the evidence supporting the interest in targeting the adenosine modulation system to counteract the core features of schizophrenia. This interest is forwarded by the combined ability of strategies aimed at bolstering adenosine levels together with the increasingly recognized impact of adenosine A2A receptors to control dopaminergic signaling, working memory, and behavioral sensitization; this is further heralded by the suggested clinical effectiveness of therapies increasing extracellular adenosine such as dipyridamole and allopurinol and the emergent recognition of a role for adenosine in neurodevelopment. Finally, the combined role of A1 and A2A receptors in assisting the implementation of adaptive changes and encoding of information salience in neuronal circuits together with the adaptive alterations of A1 and A2A receptor density upon brain dysfunction prompts the novel working hypothesis that the parallel imbalance of adenosine formation and of A1 and A2A receptors blurs the adequate encoding of information salience in neuronal circuits, which we propose to be a core pathogenic feature in the development of schizophrenia endophenotypes. This proposal should also provide a rationale to assist the design of future therapeutic intervention targeting the adenosine modulation system to manage schizophrenia endophenotypes: these should not be based only on an attempt to target adenosine kinase-A1 receptors or only A2A receptors, but should instead simultaneously target these two arms of the adenosine modulation system.International Review of Neurobiology 01/2014; 119C:395-449. · 2.46 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: The assessment of quality of life in clinical practice in patients with schizophrenia The aim of the present article is to review QoL scales used in studies investigating patients with schizophrenia over the past 5 years, and to summarize the results of QoL assessment in clinical practice in these patients.. Literature available from January 2009 to December 2013 was identified in a PubMed search using the key words "quality of life" and "schizophrenia" and in a cross-reference search for articles that were particularly relevant. A total of n=432 studies used 35 different standardized generic and specific QoL scales in patients with schizophrenia. Affect-ive symptoms were major obstacles for QoL improvement in patients with schizophrenia. Though positive symp-toms, negative symptoms, and cognitive functioning may be seen as largely independent parameters from subjec-tive QoL, especially in cross-sectional trials, long-term studies confirmed a critical impact of early QoL improvement on long-term symptomatic and functional remission, as well as of early symptomatic response on long-term QoL. Results of the present review suggest that QoL is a valid and useful outcome criterion in patients with schizophrenia. As such, it should be consistently applied in clinical trials. Understanding the relationship between symptoms and functioning with QoL is important because interventions that focus on symptoms of psychosis or functioning alone may fail to improve subjective QoL to the same level. However, the lack of consensus on QoL scales hampers research on its predictive validity. Future research needs to find a consensus on the concept and measures of QoL and to test whether QoL predicts better outcomes with respect to remission and recovery under consideration of different treatment approaches in patients with schizophrenia.Dialogues in clinical neuroscience 06/2014; 16(2):185-195.
- [Show abstract] [Hide abstract]
ABSTRACT: Background Severe mental illness (SMI), including schizophrenia, bipolar disorder and severe depression, is responsible for a substantial proportion of disability in the population. This article describes the aims and design of a research study that takes a novel approach to targeted prevention of SMI. It is based on the rationale that early developmental antecedents to SMI are likely to be more malleable than fully developed mood or psychotic disorders and that low-risk interventions targeting antecedents may reduce the risk of SMI.Methods/DesignFamilies Overcoming Risks and Building Opportunities for Well-being (FORBOW) is an accelerated cohort study that includes a large proportion of offspring of parents with SMI and embeds intervention trials in a cohort multiple randomized controlled trial (cmRCT) design. Antecedents are conditions of the individual that are distressing but not severely impairing, predict SMI with moderate-to-large effect sizes and precede the onset of SMI by at least several years. FORBOW focuses on the following antecedents: affective lability, anxiety, psychotic-like experiences, basic symptoms, sleep problems, somatic symptoms, cannabis use and cognitive delay. Enrolment of offspring over a broad age range (0 to 21 years) will allow researchers to draw conclusions on a longer developmental period from a study of shorter duration. Annual assessments cover a full range of psychopathology, cognitive abilities, eligibility criteria for interventions and outcomes. Pre-emptive early interventions (PEI) will include skill training for parents of younger children and courses in emotional well-being skills based on cognitive behavioural therapy for older children and youth. A sample enriched for familial risk of SMI will enhance statistical power for testing the efficacy of PEI.DiscussionFORBOW offers a platform for efficient and unbiased testing of interventions selected according to best available evidence. Since few differences exist between familial and ¿sporadic¿ SMI, the same interventions are likely to be effective in the general population. Comparison of short-term efficacy of PEI on antecedents and the long term efficacy for preventing the onset of SMI will provide an experimental test of the etiological role of antecedents in the development of SMI.BMC Psychiatry 12/2014; 14(1):344. · 2.24 Impact Factor