Primary negative symptom status ‘unstable’ over time in FES patients
MedWire News: Initial primary negative symptom (PNS) status in patients with first-episode schizophrenia (FES) is not predictive of primary negative symptom status over time, Chinese research indicates.
"Negative symptoms have long been considered as the core feature of schizophrenia, and constitute a discrete psychopathological dimension separate from reality distortion, disorganization, and cognitive impairment," explain Wing Chung Chang (University of Hong Kong) and team.
However, they add that few studies have examined the evolution and trajectory of PNS over time in patients with FES.
To address this, the team studied 93 patients, aged 18-55 years, who had experienced FES.
All of the participants were evaluated at baseline and after 1, 2, and 3 years using the Positive and Negative Syndrome Scale (PANSS), the High Royds Evaluation of Negativity Scale (HEN), the Montgomery-Asberg Depression Rating Scale (MADRS), and the Simpson-Angus Scale (SAS).
Clinically significant negative symptoms were defined as a total score on the HEN subscale for Affect, Behavior, or Speech of 6 or higher, or if total score on the Functioning subscale was 8 or higher. Absence of depression and extra-pyramidal signs were defined as a MADRS total score of less than 16 and a SAS mean score of less than 0.3.
Patients who met criteria for clinically significant negative symptoms, but without depression and extra-pyramidal signs were considered as having PNS.
In total, 25.8% of patients exhibited PNS at baseline, and the prevalence of PNS at different time points over the 3-year follow-up period ranged from 24.7% to 33.3%.
The researchers found that 25.0% of patients with PNS at baseline continued to exhibit PNS after 1 year; 69.9% who were categorized as having primary negative symptoms at 1 year maintained this status upon reassessment at 2 years, and 71% of patients presenting with PNS at 2 years continued to exhibit these symptoms at 3 years.
Overall, the 3-year prospective consistency of primary negative symptoms was just 16.7%, the researchers note.
Factors associated with persistent PNS included male gender, unemployment at baseline, increased duration of untreated psychosis, poorer premorbid academic and social functioning, and poorer insight.
Chang and team conclude in the journal Schizophrenia Research: "Clinical status of PNS in first-episode schizophrenia-spectrum disorder was unstable in the initial year of treatment. Baseline symptom assessment may not reliably predict development of persistent PNS."
They add that further research is needed to "clarify the longitudinal course of PNS, which will in turn facilitate early detection and intervention of these debilitating symptoms."
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By Mark Cowen