Prodrome negative symptoms predict experiential symptoms
medwireNews: Patients with schizophrenia spectrum disorders have an increased likelihood of having experiential negative symptoms, such as avolition-apathy and anhedonia-asociality, at first presentation for treatment if they had negative symptoms during the prodrome phase, research suggests.
The investigators, led by John Lyne (Dublin and East Treatment and Early Care Team Services, Dublin, UK), note, however, that "further research is needed to define which symptoms are phenomenologically similar to first presentation negative symptoms and which are more characteristic of depressive symptoms."
They add: "This could influence strategies for the detection and active management of these symptoms in a clinical high risk population."
A total of 373 individuals who were diagnosed with first-episode psychosis, either a schizophrenia spectrum disorder (n=155) or non-schizophrenia spectrum disorder (n=218), completed the Scale for Assessment of Negative Symptoms (SANS) and the Beiser Scale to determine prodrome-onset negative symptoms (PONS).
PONS were common, particularly among patients with schizophrenia spectrum disorders, with a prevalence of 50.3% and 31.2% for patients with non-schizophrenia spectrum disorders. The corresponding rates of negative symptoms at first presentation were 67.1% and 24.3%.
Among patients with schizophrenia spectrum disorders, the presence of PONS was associated with a significant 2.4-fold increased risk for SANS experiential negative symptoms at presentation, after taking into account potential confounding factors.
However, PONS was not associated with an increased risk for experiential negative symptoms in patients with non-schizophrenia spectrum disorders, and did not predict expressivity negative symptoms, such as affective flattening and alogia, in either group.
The researchers suggest that the development of experiential negative symptoms in the early phase of illness could be due to "a biological phenomenon affecting areas of cognition, such as motivation and experience of emotions, a cognitive behavioural response to perceived changes in the environment, or may represent early illness functioning deficits."
They also note in European Psychiatry that first presentation experiential symptoms were present for half of the study participants without PONS, "indicating that experiential symptoms may also begin following onset of frank psychotic symptoms, or perhaps in the premorbid period preceding the psychosis prodome."
They conclude: "The potential for use of experiential symptoms as a marker of transition to schizophrenia is another area worthy of investigation."
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By Lucy Piper, Senior medwireNews Reporter