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By Philip Kaiser and Pernille Sunde. The schizophrenia prodrome: promise for prevention. Schizophrenia. Mental disorder often characterized by abnormal social behavior and failure to recognize what is real.
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By Philip Kaiser and Pernille Sunde The schizophrenia prodrome: promise for prevention
Schizophrenia • Mental disorder often characterized by abnormal social behavior and failure to recognize what is real. • Positive symptoms: Delusions, distorted thoughts, gustatory, auditory, visual and tactile hallucinations, typically regarded as manifestations of psychosis. • Negative symptoms: little emotion, poverty of speech, inability to experience pleasure, lack of desire to form relationships and lack of motivation.
The schizophrenia prodrome: promise for prevention • Identify susceptible individuals • At what stage of the prodrome should medication be initiated • How long should medication be continued • What medication is optimal for each phase of the prodrome
The prodrome is considered to be the stage of schizophrenia that begins with the first changes in behavior and last up until the onset of psychosis. Duration is highly variable, from weeks to years, although typically it lasts for at least a year. The prodrome
The schizophrenia prodrome: promise for prevention • Increasing support for schizophrenia as a neurodevelopmental disorder. • Emerging evidence that early treatment improves outcome. • The introduction of novel antipsychotic medication, potentially providing tools for preventative intervention.
Theory and Background • Neurodevelopment view • Basic biological errors that occurs early, which includes a genetic component. • Structural, functional and/or biochemical abnormalities in the developing brain • Later in life, poorly understood stressors can further affect the development of schizophrenia • The unfolding of the clinical illness is a long-term process
Characterizing the prodrome • A number of studies looked at signs and symptoms preceding onset by patients in the early onset of the illness and their family members. • McCorry et. al. in Australia • Their system consists of three separate categories of selection criteria: • Category 1: at least one of different positive symptoms • Category 2: individuals that have experienced transient psychotic symptoms (resolving in <1week) • Category 3: combines genetic risks with a state change in functioning
Unanswered questions • Heterogeneity and false positive identifications • Negative symptoms • Medication issues; what kind to use, when and for how long.
Heterogeneity and false positive identifications • There is a question if the prodrome should be considered as a unitary clinical entity and whether it is as heterogenous as the disease itself. • Most criteria mentioned derive from positive symptoms, and might be overly restrictive and lead to a high false positive rate.
Negative symptoms • There is considerable evidence to suggest that negative symptoms are important characteristics of the prodromal phase of the illness. • Studies have shown that negative symptoms, such as social deficit, are more easily detected early in the development, prior to the onset of positive symptoms. • Focusing on both positive and negative symptoms most accurate way of defining the prodrome?
Current studies • Non-pharmacological studies: • UK based study • Other studies showed that after 1 year follow-up showed that treatment was favored, but neither groups of patients differed significantly at 2 year follow-up
Conclusion Even though there have been conducted several studies on the topic, so far none of them have provided conclusive evidence in how to best treat or prevent the onset of psychosis after the onset of the prodrome. However, this does not necessarily mean that intervention in an early phase of the disease is ineffective, only that we have not found an effective method in doing so yet.
Sources • Dialogues in clinical neuroscience, Schizophrenia: Specific topics, Volume 3; No. 2, 2001. • Mayo Clinic 2015, Schizophrenia, http://www.mayoclinic.org/diseases-conditions/schizophrenia/basics/definition/con-20021077 • http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3136161/